Comunicata Scientiae

Genetic parameters and selection gains in open-pollination progenies of bacabi palm tree (Oenocarpus mapora)

2023-09-04T08:22:11-03:00

The Bacabi (Oenocarpus mapora Karsten) is an Amazonian palm whose fruit is widely used in the food industry due to its organoleptic properties and excellent nutritional quality. The objective of this work was to estimate genetic parameters and selection gains in the selection of open pollinated bacabi progenies. The experiment was carried out in the district of Campo Limpo, in the municipality of Santo Antônio do Tauá, state of Pará. The study assessed 38 progenies from open‑pollination under an agroforestry system in a randomized block design with five replicates and two plants per plot. At Seventeen, Twenty-four and Thirty months after planting, data were collected on the following traits: stem height (SH), plant diameter (DIAM), number of live leaves (NLL), length of the leaf rachis (LLR), number of leaflet pairs (NLP) and leaflet length (LL). Genetic variety was observed among and within progenies for all evaluated traits. The broad‑sense heritability estimates varied between 0.13 and 72.81%. High values were found for NLP (72.81%), DIAM (52.01%), LLR (62.64%), and SH (66.16%). Selection gains can be achieved for all the traits evaluated, with selection of 30% among progenies and 20% inside progenies.

Substrate combinations in potato planting to increase the production of minitubers

2023-02-20T19:31:35-03:00

The profitability and initial development of potatoes depend on the type of substrate used in planting. Therefore, this study aimed to evaluate combinations of substrates for the production of minitubers of potatoes. An experiment was carried out with the combinations of substrates based on sphagnum peat, coconut fiber, rice husks, and expanded vermiculite [TFCV]; and sphagnum peat and expanded vermiculite [TV], in different proportions (100%; 75%; 50%; 25%), with five replications. The treatments were: (i) TFCV_100%; (ii) TFCV_75%+TV_25%; (iii) TFCV_50%+TV_50%; (iv) TFCV_25%+TV_75%; and (v) TV_100%. At 40 and 70 days after planting (DAP), the development of shoots, tubers, and roots was monitored. Results showed that the isolated application of TV showed the highest production of fresh mass of tubers (93.0 g), and fresh (0.28 g) and dry mass of roots (0.17 g). At 40 DAP, tuber production was highly correlated with the root part (r: 0.77). However, after 70 DAP, tuber production was associated with shoot development (r: 0.66). If is necessary to mix substrates recommend the mixing of TFCV_50%+ TV_50%. The addition of coconut fiber and rice husk increases the availability of nutrients in the substrate with a positive effect on the aerial development of the plants.

Colletotrichum species associated with atemoya anthracnose in northeast Brazil

2023-10-08T12:26:00-03:00

Anthracnose, caused by Colletotrichum spp., is an important disease of atemoya that can infect and cause damage to different plant organs. The symptoms include foliar anthracnose, flower abortion, branch tip bleaching, and necrotic lesions on fruits. Knowing the etiology of this disease is essential for properly developing management strategies. Therefore, this study aimed to identify Colletotrichum species associated with atemoya in the Northeast region of Brazil, based on multi-locus phylogeny and morphological analyses, to better understand the etiology of anthracnose in this plant species. The Colletotrichum isolates were obtained from symptomatic leaves and branches of atemoya collected in commercial fields in Vitória da Conquista (Bahia), Palmeira dos Índios and Rio Largo (Alagoas), located in northeast Brazil. The initial analysis of the partial sequences of the GAPDH gene was performed with nineteen Colletotrichum isolates obtained from leaves and branches of atemoya trees with typical anthracnose symptoms. Seventeen isolates were grouped in the gloeosporioides complex and two in the boninense complex. Therefore, eleven isolates were submitted to concatenated phylogenetic analyses with the genes GAPDH, TUB2, and ITS region of the rDNA to confirm the identity of the isolates at the species level. The species C. theobromicola, C. siamense, C. fructicola and C. karstii were identified and are associated with atemoya anthracnose in the Northeast region of Brazil.

Melon cultivation under agrotextile increases production and reduces phytosanitary products

2023-08-03T10:22:15-03:00

Abiotic and biotic factors influence the productivity and quality of melon fruit; therefore, the protection of plants using agrotextile mesh is a solution that can be agronomically viable, as it reduces the use phytosanitary pesticides and allows for greater productivity and, consequently, quality. The objective this study was to evaluate the influence of coverage time with an agrotextile (0, 21, 26 and 31 days after transplanting (DAT)) in melon hybrids ‘Gold Mine’, ‘Soleares’, ‘Lual’ and ‘Natal’ on productivity and fruit quality attributes. The plants that were protected with agrotextile mesh for 21 and 26 DAT had higher productivity (53.5 and 52.1 t ha⁻¹). Among the hybrids, all excellent plots produced above 42.4 1 t ha⁻¹. Of the observed hybrid quality parameters, 'Natal' protected for 21 DAT showed a better total phenol content and a higher maturation index, and 'Soleares' protected for 21 DAT showed a higher DPPH antioxidant activity and flavonoid content.

English Growth and yield of Brazilian potato cultivars

2024-03-06T07:14:54-03:00

The analysis of plant growth of cultivars is useful for understanding the dynamics of accumulation and partition of photoassimilates during the crop cycle, and this information is important for the crop management of each cultivar. The objective of this study was to evaluate potato cultivars BRS Ana, BRSIPR Bel, BRS Clara, BRS F63 (Camila) and Macaca for growth and yield, under subtropical climatic conditions of Southern Brazil. Plant samples were collected every 20 days, beginning 40 days after planting (DAP), totaling five collections, and physiological growth indexes and the dry mass partitioning to plant organs were estimated. ‘BRSIPR Bel’ showed the fastest development of assimilatory system. ‘BRS Ana’ had the most vigorous plants and the largest leaf area, reaching the leaf area index 4.0 at 70 DAP. ‘BRSIPR Bel’ e ‘BRS Ana’ had the highest dry mass yield, 214 g and 206 g of dry mass plant^-1, respectively. ‘BRS F63’ (Camila) and ‘BRSIPR Bel’ presented earlier tuberization and were the most efficient cultivars in the partitioning of dry mass to tubers, with the highest coefficient of dry mass partitioning to tubers estimated between 40 and 64 DAP. These two cultivars also showed the highest yield of marketable tubers.

Organic cultivation of Allium fistulosum under concentrations of Bordeaux mixture

2022-12-13T22:05:42-03:00

Allium fistulosum L., belonging to the botanical family Alliaceae, is one of the most produced and commercialized vegetables in the world. In this scenario, this study aimed to evaluate the control of anthracnose in chives subjected to organic cultivation with different concentrations of Bordeaux mixture and its effects on crop yield. The experiment was conducted in elevated soil beds 10-cm high. Seedlings of the chive cultivar ‘Todo Ano’ were produced from plants previously cultivated in the site. Cultivation was carried out under full sunlight, and irrigation was performed by automatic sprinklers with a daily volume of 6 mm. The experiment was in randomized blocks, with 10 treatments in a 2x5 factorial arrangement. Four concentrations of Bordeaux mixture (0.5%; 1.0%; 1.5%; 2.0%) plus one control (water) were used. The second factor evaluated was the weekly and fortnightly application period. Data on the Total Fresh Mass (MFT), Commercial Fresh Mass (MFC), Sick Fresh Mass (MFR), Number of Commercial Leaves (NFC), Number of Sick Leaves (NFR), Commercial Dry Mass (MSC), and Yield (PTV) were collected. No statistically significant interactions were observed for anthracnose control and chive yield. However, in the 4th week of evaluation, differences were observed between the application periods, with the 2.0% concentration and weekly application performing better than the other treatments. The other evaluations did not result in significant statistical interactions between the variables analyzed. The application of Bordeaux mixture has no effects on the control of anthracnose and on the yield of chives.

Physiological and growth responses of lettuce plants submitted of 2,4-D simulated drift

2023-08-03T10:29:37-03:00

Pesticide drift is due to the transport of the active ingredient to areas not targeted by spraying, causing negative effects on the sensitive crops’ development. The aim of this study was to evaluate lettuce response to simulated 2,4-D drift. Experiments were conducted in the greenhouse, in a randomized complete block design with four replications. The treatments consisted of nine different doses of the 2,4-D herbicide, which are: 0; 1.56; 3.125; 6.20; 12.5; 25; 50; 75; and 100% from the recommended dose (670 g a.a. ha^-1). The application occurred when the lettuce plants had four to six true leaves. The analyzed variables were visual injury (phytotoxicity), development parameter (phyllochron), growth (rosette diameter and dry mass of the aerial part), and photosynthetic parameters (gas exchange). The lettuce crop showed high sensitivity to the 2,4-D herbicide, with the lowest dose resulting in significant phytotoxic damage to plants, and from 12.5% of the recommended 2,4-D dose, visual injuries were greater than 90%. The plants´ development and growth were negatively affected by the increased drift doses, culminating in enhanced phyllochron and reduction in rosette diameter and dry mass of the aerial part. The gas exchange of the crop was affected from 6.20% of the recommended dose, causing a reduction in the CO₂ assimilation rate, stomatal conductance, transpiration rate and rubisco carboxylation efficiency.

Production and composition of peppermint essential oil in seasons after summer and winter transplantations

2023-08-05T09:19:30-03:00

The aim of this study was to determine the season that provides the highest production and best quality of peppermint (Mentha x piperita L.) essential oil in summer and winter transplantations. Two experiments were performed in a protected cultivation, the first with transplantation in summer and the second with transplantation in winter, with a completely randomized design with four treatments, being the seasons of the year. Content, yield and chemical composition of the essential oil were determined. The essential oil was extracted by hydrodistillation and analyzed by gas chromatography. Essential oil content in summer and winter transplantations was higher in summer and essential oil yield was higher in spring. In the summer transplanting the major components were menthone, isomenthone and pulegone. In the winter transplanting menthone, menthofuran, isopulegone, pulegone and menthol were detected as major components. Menthofuran, a compound which reduces the essential oil quality, were found in high amounts in winter transplanted plants. The higher production of peppermint essential oil is obtained in summer and spring harvests and the main compound is menthone in all seasons. The best quality of essential oil is obtained in the summer transplanting.

Morpho-physiological responses of potato cultivars under weed competition

2023-05-08T12:46:27-03:00

Among the factors that affect potato productivity, the interference caused by weeds stands out as they may compete with the crop, release allelopathic substances to soil and host insects and diseases. Therefore, the objective of this work was to assess the competitive ability of white (Aghata) and pink (Asterix) potato cultivars when infested by Alexandergrass (Urochloa plantaginea) or wild poinsettia (Euphorbia heteroplylla). The experiment was carried out into greenhouse in randomized blocks design, with four replications. A single potato plant faced competition by either Alexandergrass or wild poinsettia, ranging from 0 to 64 plants per plot. Fifty days after seedling transplanting, variables related to the morphophysiology of potato cultivars and weeds were assessed. Potatoes have low competitive ability with both weed species, with wild poinsettia being the most aggressive in reducing the accumulation rates of leaf area and aboveground dry mass. Potato photosynthetic rate is negatively influenced by the presence of both weeds. Internal CO₂ concentration, stomatal conductance, carboxylation efficiency and transpiration rates of potato varied depending on weed species and density. Morphological parameters are reduced when potato competed with Alexandergrass or wild poinsettia; however the physiological parameters are most sharply affected when under competition with wild poinsettia.

Are pyroxasulfone and pyroxasulfone plus flumioxazin options for application in transplanted onions?

2024-03-06T09:22:12-03:00

This study aimed to evaluate the efficiency and selectivity of the herbicides pyroxasulfone and pyroxasulfone plus flumioxazin for transplanted onion, which currently do not have registration for this crop in Brazil. The experiment was conducted in two commercial crops in Imbuia and Curitibanos, SC, Brazil, with four replications. The herbicides application was carried out pre-emergence of weeds, after onion transplanting in both experiments. The Imbuia experiment had eight treatments: T1: diuron (D) + pyroxasulfone (PYR) (500 + 50 g ha^-1), T2: D + PYR (500 + 75 g ha^-1), T3: D + PYR (500 + 100 g ha^-1), T4: D + PYR + flumioxazin (FLU) [500 + (60 + 40 g ha^-1)], T5: D + PYR + FLU [500 + (75 + 50 g ha^-1)], T6: D + PYR + FLU [500 + (90 + 60 g ha^-1)], T7: Weed free check, and T8: Control. In Curitibanos, had an additional treatment, with application of diuron (500 g ha^-1). Evaluation consisted of identification and weed control, crop phytotoxicity, onion stand, and diameter and yield of bulbs. Pyroxasulfone and pyroxasulfone plus flumioxazin, with diuron, were effective in control of Polygonum persicaria, Galinsoga parviflora, and Coronopus didymus, regardless of the dose used. Diuron with pyroxasulfone at a dose of 100 g ha^-1and with pyroxasulfone plus flumioxazin (60 + 40, 75 + 50, and 90 + 60 g ha^-1) were effective in Raphanus spp. control in boths experiments. The control showed losses in its total yield compared to the weed free check, decreasing by 81,7% in Imbuia and 90,3% in Curitibanos. The herbicides used were selective and are importante tools for weed management in transplanted onion.

Effective microorganisms on the development of green cabbage

2023-03-21T18:40:28-03:00

The cabbage culture has economic importance for small farmers, being one of the most consumed vegetables in Brazil, which demands more sustainable and low-cost technologies for its cultivation. Thus, the objective of this work was to analyze the influence of fertilization with biofetilizer enriched with effective microorganisms (EM) on the development of green cabbage (Brassica oleracea var. capitata.) in agroecological production management. The experimental design was in randomized blocks with four treatments: (T1 – 0.0%; T2 – 5.0% (0.25 L of inoculated solution for 5 L of dechlorinated mineral water); T3 - 10% (0. 5 L of inoculated solution to 5 L of dechlorinated mineral water) and T4 – 20% (0.75 L of inoculated solution to 5 L of dechlorinated mineral water) and 5 replications. Traits of growth, development and production were evaluated. The data were submitted to analysis of variance and linear regression. The characteristics circumference, longitudinal diameter, transversal diameter, marketable fresh mass, total fresh mass, nitrogen content, protein and moisture showed significant effects in response to EM doses. In general, the regression model with the best fit was the quadratic, with the maximum points close to the 10% dose of effective microorganisms, which is recommend for cabbage crops under agroecological production management.

Chloroplast pigments, water relationships, and growth of bell pepper under salt stress and nitrogen

2022-12-14T14:39:26-03:00

The use of saline water sources for irrigation in semi-arid regions is a challenge for horticultural production since plants are sensitive to salt stress conditions, thus requiring techniques that allow plant acclimation, including nitrogen fertilization. From this perspective, this study aimed to evaluate the chloroplast pigments, water relationships, and growth of bell pepper plants irrigated with saline water and subjected to nitrogen fertilization. The experiment was conducted under field conditions at the Federal University of Campina Grande, Pombal - PB, where a randomized block design was adopted with a 5 x 5 factorial arrangement corresponding to five electrical conductivity levels of irrigation water (0.3, 1, 1.7, 2.4, and 3.1 dS m^-1) and five nitrogen levels (50, 75, 100,125, and 150% of the dosage recommended for the crop), with three replications. The 125 and 150% N levels provided the highest relative water contents in bell pepper plants irrigated with electrical conductivity levels of up to 1.7 dS m^-1. The contents of chlorophyll a, b, total chlorophyll, carotenoids, and stem diameter of bell pepper plants decreased when fertilized with 150% N and irrigated with the electrical conductivity of 3.1 dS m^-1.

Carpochron: a concept for the time interval between the appearance of fruits in consecutive harvests

2023-07-19T11:26:16-03:00

The aim of this research was to estimate the base temperature for the appearance of fruits at harvest point in the strawberry and to propose a concept to represent the time required for the appearance of fruits in consecutive harvests. The experiment was conducted in 2021 in four seedling transplanting seasons: May (season 1), June (season 2), July (season 3) and August (season 4) of two cultivars: Fronteras and Merced. Twenty-four consecutive fruit harvests were carried out from September 9, 2021, to December 1, 2021, when the number, length (cm), diameter (mm), and fresh weight of the fruits (g) were evaluated. The base temperature for the fruit emission of the strawberry was calculated using the method of the smallest mean square error. Carpochron was estimated at each season and for each cultivar, obtaining a simple linear regression between the number of fruits and the accumulated thermal sum (ºC day) and the number of days after transplanting (DAT), using as base temperature the one estimated in this work. The base temperature for the appearance of consecutive fruits at the harvest point in the strawberry is 11ºC. Carpochron increases with the delay of the transplanting season and the values ranged from 81.97ºC fruit day to 144.93ºC fruit day for cultivars Merced and Fronteras.

Production and quality of watermelon subjected to biofertilizer fertilization

2022-12-14T13:59:43-03:00

The expansion of the area with organic agriculture is due to the market trend towards the consumption of healthier foods. However, with the increase in the cost of fertilizers imported by the country, the adjustment of doses and management practices with alternative sources for plant nutrition, such as biofertilizer, can be an alternative for the sustainability of properties. The experiment was conducted in the experimental field of Bebedouro (CEB) of EMBRAPA Semi-Arid Region in Petrolina-PE, Brazil, from September to December 2019, to evaluate the effect of biofertilizer doses on the production aspects of three watermelon varieties in the semi-arid region. The experimental design was randomized blocks, in a 6 x 3 factorial scheme, corresponding to six doses of biofertilizer (0; 80; 160; 240; 320 and 400 mL plant^-1) and three varieties of watermelon (Explorer, Red Heaven, and Majestic), with four replicates. Yield, number of fruits per plant, average fruit mass, fruit diameter, fruit length, length: diameter ratio, pulp firmness, rind thickness, pH, total soluble solids, titratable acidity and soluble solids/titratable acidity ratio were analyzed. The number of fruits per plant was not altered by biofertilizer doses. However, the variables yield and average fruit mass were altered by the interaction between varieties and biofertilizer doses. With yield of 40.22 t ha^-1 obtained at the dose 201.33 mL plant^-1, the Explorer variety proved to be more efficient with the use of biofertilizer in organic system. Positive responses to biofertilizer application in postharvest quality attributes were obtained in Explorer and Red Heaven varieties.

Toxicity of anthranilamides used in cucurbit cultivation on Apis mellifera

2023-08-02T12:16:52-03:00

This study aimed to evaluate the toxicity of insecticides belonging to the chemical group Anthranilamide on Apis mellifera. Toxicity was evaluated in the two experiments, which corresponded to two exposure modes: direct spraying of the products on the bees and ingestion of a contaminated diet. The two bioassays were performed in a completely randomized design composed of eight treatments (absolute control – distilled water; positive control: Thiamethoxam at 0.03 and 0.3 g.a.i. L^-1; Chlorantraniliprole: 0.015 g.a.i. L^-1; Cyantraniliprole: 0.05 and 0.1 g.a.i. L^-1; Chlorantraniliprole + Abamectin: 0.027+0.0108 g.a.i. L^-1 and 0.045+0.018 g.a.i. L^-1), with 10 replications each. Via exposure through direct spraying, the insecticide Chlorantraniliprole + Abamectin, regardless of the dose used, caused 100% bee mortality, showing a TL₅₀of 10.05h and 8.36h for the minimum and maximum doses, respectively. The insecticide Cyantraniliprole caused the death of 33.1% and 44.9% of the bees, respectively at the minimum and maximum doses, with a TL₅₀ of 87.79 h for the two doses. The insecticide Chlorantraniliprole showed the lowest mortality rate, 24.7%, with a TL₅₀ of 118.88h. Via ingestion of a contaminated diet, the insecticide Chlorantraniliprole + Abamectin caused 100% mortality and showed a TL₅₀ of 27.83h and 24.01h at the minimum and maximum doses, respectively. The insecticide Cyantraniliprole caused the death of 67.6% and 68.1% of bees at the minimum and maximum doses, respectively, with a TL₅₀ of 58.63 h for the two doses. Chlorantraniliprole shows the lowest mortality rate, 48.1%, and a TL₅₀ of 79.68h.

Microalga as biofertilizer improves yield, sugars and amino acids content in red beets

2023-08-02T12:14:00-03:00

The growing uncertainty of future changes in our global climate may pose a threat to some traditional farming methods, stimulating the development of nature friendly technologies. Microalgae are a group of micro photosynthetic organisms, which have immense potential as a renewable and ecofriendly bioresource for various industries. The present study was developed to evaluate foliar sprays of a green microalga Asterarcys quadricellulare (CCAP 294/1) on organically grown red beets (Beta vulgaris L) A field experiment was implemented to evaluate microalgal biomass bioactivity and its effects in leaves and hypocotyl growth, comparing fresh and dry weight, yield; and biochemical alterations, comparing pigments, sugars and free amino acids. The spray dried biomass of the A. quadricellulare was applied to leaves at concentrations 0.05g, 0.1 g, 0.15g and 0.25 g L^-¹. The sprays with the microalga biomass increased yield, and improved free amino acids, sugars, dry weight and beets commercial diameter. This study shows that the foliar sprays presented a biofertilizer effect, emphasizing the solution at 0.25 g L-¹, which resulted in a 52% increase in yield. The results indicate that the microalga is a nature friendly, renewable and economic resource for red beet production.

Compatibility of wild rootstocks in the production of cherry tomato seedlings

2023-07-24T12:53:31-03:00

Growing tomato crops is a highly significant activity in Brazil; however, several factors limit tomato productivity, mainly soil-borne diseases which, without proper control, can compromise the entire crop production. The proper use of grafting techniques emerges as an alternative to overcome barriers that limit tomato production in regions with unfavorable growth conditions. The use of rootstocks resistant to root diseases is seen as a viable option for tomato production. In this context, the objective of this work was to evaluate the compatibility and efficiency of rootstocks for cherry tomatoes. A randomized block design was used, with five treatments and four replications; each plot consisted of 36 grafted seedlings. The treatments consisted of rootstocks of Eggplant, Jurubeba, Jilo, and Tomato (Intacto; Feltrin Sementes^®), and a Control (cherry tomato without grafting). All rootstocks were compatible with cherry tomatoes. Moreover, seedlings grafted onto Jurubeba rootstocks presented results closest to the Control (cherry tomatoes). Seedlings grafted onto Jurubeba and Eggplant rootstocks presented the best results regarding vegetative development and total dry matter accumulation. Jurubeba and Eggplant rootstocks are viable alternatives for grafting cherry tomato seedlings. All utilized rootstocks can be further investigated for their resistance to root diseases affecting tomato crops.

Organic Fertilization in 'Pérola' Pineapple Increases Fruit Production and Physical and Chemical Characteristics

2023-08-01T15:11:58-03:00

Pineapple is the third most cultivated tropical fruit in the world. However, few studies have focused on the cultivation
using organic fertilization, especially in semiarid regions. Thus, this study aimed to evaluate growth, production and
physicochemical traits of pineapple fruits produced under organic fertilization in the semiarid. The experiment was
carried out at the didactic orchard of Federal Rural University of Semiarid, Mossoró, Rio Grande do Norte, Brazil. Four
fertilization treatments were studied (chemical fertilizer, cattle manure, goat manure, poultry litter). At 18 months
after planting, plant growth, physicochemical traits of fruits, and productivity were evaluated. Results showed that
organic fertilization with poultry litter provides best results for physicochemical traits of fruits and productivity of ‘Pérola’
pineapple. Organic fertilization with poultry litter is most promising for plant growth, physicochemical traits of fruits, and
productivity in ‘Pérola’ pineapple, therefore, the most suitable for cultivation in the semiarid region. The fruit firmness,
central cylinder weight, and ratio SS/TA showed best values under chemical and goat manure fertilization.

Umbu physicochemical quality, diversity in the Caatinga biome and promising genotypes for consumption

2023-07-24T11:18:13-03:00

Umbu (Spondias tuberosa Arruda) is a wild fruit species distributed all over the Caatinga biome in the Northeast of Brazil. The objective of this study was to analyze the physicochemical quality variability of umbu genotypes in the Caatinga biome, and to identify the most promising ones for fresh fruit consumption, processing industry and breeding programs. The fruit of 69 umbu genotypes were harvested at the maturity stage known as swollen, presenting full size and beginning of softening. The plants were cultivated in the umbu germplasm bank (UGB) at the Brazilian Agricultural Research Corporation, Embrapa, Petrolina, PE, Brazil. Each genotype was characterized by the global position system (GPS) coordinates to understand the distribution of fruit physicochemical quality in different regions in the Caatinga biome. According to the results, fruit physicochemical quality, such as mass, soluble solids (SS), titratable acidity (TA), and SS/TA ratio are homogeneously distributed all over the Caatinga biome. However, there were three main genotype groups, one characterized by higher fruit mass (52, 55, 57, 60, 65, and 68), other by higher SS (08, 09, 11, 20, 38, 41, and 62), and another by lower AT (02, 03, 07, 08, 16, 24, 27, and 51). Umbu genotypes with the highest mass and SS content can be used for commercial production in order to obtain fruit with desirable trait for the market. In addition, genotypes from all three groups can be used in breeding programs to obtain new genotypes with all desirable traits for fresh fruit consumption and processing industry.

Effects of Thidiazuron and Pollinator visits on Fruit Set and Quality of 'Maxigala' Apple Trees

2023-08-05T09:15:33-03:00

The objective of this study was to assess the effects of thidiazuron (TDZ) application and pollinator visits on fruit set and quality in apple trees of the cultivar Maxigala. The experiment was conducted at the Temperate Fruit Farming Experimental Station of the Brazilian Agricultural Research Corporation (EMBRAPA Grape and Wine), in Vacaria, RS, Brazil. The evaluated treatments were: TDZ application; floral visitors combined with TDZ application; floral visitors; and control (no floral visitors with no TDZ application). The highest mean final fruit set was found for the treatment with only TDZ application, followed by that with floral visitors and TDZ application.

Reflector materials on benches act as supplementary sources of light in rucola cultivation

2023-08-02T12:03:02-03:00

The purpose of this work is to present an alternative to the use of lamp and light diodes to increase production systems that lead to better natural energy use and better plant development. The species Euruca sativa L. was used, cultivated under a protected environment, and four treatments were taken (control; glossy white laminate; bright red laminate; aluminized thermoreflective screen). Our findings showed to reduce the efficiency of laminated reflective materials in increasing rucola production. The application of the red laminate with greater efficiency, positive results with the increase of fresh matter and number of leaves, increasing the energy efficiency of the plant. Furthermore, the better use of natural light can reduce production costs, since the application of artificial light generates an increase in fixed production costs.

Lettuce yield response to application of rhizobacteria and nitrogen to the growth substrate

2023-11-03T10:57:53-03:00

Rhizobacteria of agronomic interest can promote plant growth, increase productivity, and reduce the demand for nitrogen (N) fertilizers by improving the N use efficiency in crops. The objective of this study was to assess the effects of rhizobacteria and nitrogen on the yield of lettuce plants (cultivar Vera). The experiment was carried out in a greenhouse, using a completely randomized design in a 2×2×2×2 factorial arrangement, with five repetitions. The factors consisted of single and combined applications of liquid inoculants (1 mL) based on Azospirillum brasilense, Bacillus subtilis, and Bradyrhizobium japonicum, as well as nitrogen (75 kg ha^-1) in the growth substrate. The variables assessed were total and commercial shoot fresh and dry weights, root dry weight, total dry weight, and numbers of total and commercial leaves, and shoot nitrogen content. Lettuce yield components improved with nitrogen fertilizer application. The single application of rhizobacteria did not increase lettuce yield, as the plants had decreases in root weight in response to Bradyrhizobium japonicum and decreases in total and commercial shoot dry weights, root dry weight, and total dry weight when Bacillus subtilis was used. However, the combined application of Azospirillum brasilense, Bacillus subtilis, and nitrogen increased the lettuce number of commercial leaves and shoot nitrogen content when one or another microbial specie was associated with nitrogen fertilizer.

Morphophysiology of Punica Granatum L. under microalgae biomass stimulation

2023-05-08T11:02:55-03:00

The use of microalgae has been proeminent in agricultural scenario, because it is an alternative product considered extremelly productive, which contains essential elements for plants. Thus, this study aimed to evaluate the morphophysiology of Punica granatum L. seedlings treated with Spirulina platensis and Scenedesmus sp. nanoparticles in controlled environment. The research was carried out at the of Federal University of Campina Grande, Pombal-PB, using a completely randomized design with five replications. The factorial scheme (2 x 4) was adopted, represented by two types of microalgae (Spirulina platensis; Scenedesmus sp.) and four doses of application (0, 5, 10 and 15%). Growth evaluations happened at 135 days after planting, verifying the number of leaves and branches and shoot length. The physiological parameters evaluated were gas exchanges, chlorophyll ‘a’ fluorescence, electron transport rate, stationary fluorescence, maximum fluorescence yield after light adaptation and quantum efficiency of PSII. Shoot length and number of branches had rises at doses of 6 and 15%. Number of leaves was induced in seedlings at dose of 8% with Spirulina platensis. Stomatal conductance and internal CO₂ concentration increased in seedlings sprayed with Spirulina platensis. extract of Scenedesmus sp. improved the stationary fluorescence and quantum efficiency of PSII in pomegranate seedlings.

Production and quality of ornamental peppers cultivated under colored shade nets

2022-12-14T17:38:10-03:00

The cultivation of ornamental peppers in places with high temperature and incidence of solar radiation limits the production and quality of plants and fruits. The colored shade nets were introduced and adopted, because they reduce the temperature and intensity of solar radiation, as well as, low cost and simple to handle. The aimed was to evaluate the production and quality of C. chinense and C. frutescens cultivated under colored shade nets. The experiment was developed in the Floriculture Sector of the Agronomy Department of the Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil from February to August 2021 in entirely randomized design. C. chinense and C. frutescens were cultivated under red, pearl and aluminet nets with 35% shading and without net. At 150 days, production variables were quantified. The red net reduced the maximum temperature by at 4.1ºC and the pearl and aluminet nets reduced the minimum temperature by 3ºC. The maximum and minimum relative humidity was increased by 2.6 and 8.5%, respectively, by the red net. The pearl net obtained the lowest percentage of solar radiation incidence. Plant height was greater in the red and pearl nets, and C. frutescens. The diameter and stem fresh matter did not differ statistically between treatments. Root length was greater in the red and aluminet nets. The longitudinal and transverse canopy ratio was higher in C. chinense cultivated under the aluminet net. The number of leaves and leaves fresh matter was higher in pearl and aluminet net, and in C. frutescens, but leaves dry matter was higher in C. chinense. The number of flower buds and flowers, and flower buds dry matter was higher in C. chinense. The root fresh matter and dry matter was greater in C. chinese. The use of colored shade nets during the cultivation period effectively reduced temperature and light intensity. The aluminet net in association with C. chinense are recommended considering the compactness of height, pot coverage, greater number, shape and arrangement of fruits.

Allelopathic potential of ethanolic extract and its fractions from leaves of Geonoma schottiana Mart.

2023-05-08T13:13:42-03:00

Geonoma schottiana Martius (Arecaceae) is an understory palm species widely distributed in Brazil. The objective of this work was to determine the allelopathic potential of Geonoma schottiana leaf extract and its fractions of different polarities and evaluate in vitro and in vivo antioxidant activities. The germination of seeds of Lactuca sativa and Panicum maximum was tested using ethanolic leaf extract and its hexane, dichloromethane, ethyl acetate, and butanol fractions. In vitro antioxidant tests were performed through the DPPH, ABTS, FRAP, and molybdenum tests, whereas the SOD, CAT, and POX enzymatic tests were used to evaluate in vivo antioxidant activity. Chemical analyses were performed through phytochemical screening of the main groups of secondary metabolites by thin-layer chromatography and quantification of the total contents of phenolics, tannins, and flavonoids. The hexane and butanol fractions had allelopathic effects on P. maximum and low activity on L. sativa. The ethyl acetate fraction presented higher antioxidant activity in the DPPH test, whereas butanol presented higher antioxidant activity in the ABTS test. The most active fractions in terms of allelopathic effect interfered with the increases in the production of SOD and POX enzymes. The most polar fractions had higher contents of phenolic compounds. All analyzed chemical groups were found in the phytochemical screening, except the anthracene group.

Português Organic fertilizer application combined with seed inoculation using rhizobacteria on tomato yield and quality

2023-08-02T11:17:41-03:00

Organic fertilizer application combined with seed inoculation using rhizobacteria enables increases in industrial tomato production. The objective of this work was to assess the synergistic effect of organic fertilizer application and seed inoculation with rhizobacteria on tomato yield and quality. A randomized complete block experimental design with four replication was used, in a 6×3 factorial arrangement consisted of six fertilizer sources (mineral fertilizer; cattle manure; and organic composts based on tomato, sugarcane bagasse, tomato + sugarcane; and tomato + sugarcane + banana stalk) and three different seed inoculation with rhizobacteria (a control, without inoculation; inoculation with RZB 18; and inoculation with LEMB 17). The evaluated fruit characteristics were: commercial and non-commercial yields; firmness; soluble solids content (SSC); industrial yield; titratable acidity (TA); SSC to TA ratio, and pH. The rhizobacteria significantly affected all evaluated characteristics. The highest mean industrial yields were obtained with the application of mineral fertilizer (7.59), tomato-based compost (7.99), and sugarcane bagasse-based compost (7.95 Mg ha^-1). Although seed inoculation with rhizobacteria did not affect fruit yield and quality, organic composts based on tomato and sugarcane bagasse residues might be used as organic fertilizer for industrial tomato production.

An Efficiency and economic viability of water management in the production of table tomatoes

2023-02-20T19:58:12-03:00

Tomato (Solanum lycopersicum L.) cultivation can be expensive, with costs exceeding BRL 100,000 per hectare, which drives the search for tactics that reduce costs. Consequently, strategies have been developed to make it viable in tropical regions and areas with water scarcity. The objective was to evaluate the cost and profitability of water management in table tomato cultivation under different irrigation schedules. This study was carried out using the Fascínio tomato hybrid and four irrigation management approaches (no cutting, 100, 105, and 110 days after sowing, DAS). Harvesting was conducted four times, and the averages were summed toCOE estimate the total and commercial production, as well as the losses, for each irrigation schedule. To calculate the cost, both the effective and total operational costs were considered, referring to the establishment of the crop and to each irrigation cut used. Several economic indicators were calculated, including gross income ($), operating profit ($), profitability index (%), gross margin ($), break-even point (kg), and price break-even point ($/kg). The cost of water for irrigation had little impact on Effective Operating Cost (EOC) and Total Operating Cost (TOC); however, the treatment without cutting irrigation provided greater total and commercial production, which reflected the profitability parameters (OP, PI, GM, break-even point, and price break-even point). The treatment without cutting irrigation was 0.13%, 0.19%, and 0.024% more profitable than the treatments with irrigation cuts at 110, 105, and 100 DAS, respectively. This increase in profitability was justified due to the higher productivity, justifying the maintenance of irrigation in tomato cultivation. The treatment without cutting irrigation provided the highest total and commercial productivity of tomato fruits, with 8099.58 and 7927.36 units, respectively, generating a higher gross revenue of $32,398.32.

Intercropping lettuce and radish as strategy for efficient water use: determination of water demand and crop coefficient

2023-02-20T19:11:27-03:00

Determining the need for water, as well as crop coefficients, is essential information for the management of irrigation and consequently efficiency in the use of water resources. The study aimed to determine the evapotranspiration and the culture coefficients of lettuce and radish in a monoculture system and consortium in a protected environment. The lettuce cultivar used was Vanda and for radish hybrid 19 was used. The reference evapotranspiration was estimated by the Penman-Monteith method using data from the automatic weather station and the evapotranspiration of the cultures was determined by the direct method using lysimeters of constant water table. The water demand for lettuce and radish in the intercropping system was 170 mm, being less than the lettuce monoculture which was 190 mm and higher than the radish monoculture which was 121 mm. The recommended average values of culture coefficient for conditions were 0.96, 1.85, and 1.50 for lettuce and 0.85, 1.28, and 1.10 for the radish in the initial, intermediate and final stages, respectively. The intercropped cultivation showed lower water consumption than the lettuce monoculture. The coefficient values of lettuce and radish in a monoculture system were higher than the standard values recommended by FAO, emphasizing the importance of conducting regional studies.

Irrigation management of Punica granatum in the Sub-Middle São Francisco River Valley: Morphophysiological aspects.

2023-05-30T15:12:41-03:00

Water availability in arid and semi-arid areas has been a limiting factor to the expansion of agricultural production in several regions of the world. In this context, this research aimed to study the morphophysiological responses of pomegranate as a function of different irrigation depths in the Sub-Middle São Francisco River Valley (SSFV). The research was carried out in a commercial area located in Petrolina-PE, Brazil, with eight-year-old plants of lineage No. 12 of Embrapa Semi-Arid, spaced 4.0 x 2.0 m. Drip irrigation with a flow of 2.4 L h⁻¹ emitter⁻¹ was used every two days. The treatments consisted of D50 – continuous irrigation deficit with 50% ET₀ replacement, D75 – continuous irrigation deficit with 75% ET₀ replacement, D100 – continuous irrigation deficit with 100% ET₀ replacement, and DF – farm irrigation. The experiment was conducted in randomized blocks with five replications. Plant height, cup diameter, number of flower buds, flowers, and fruits, relative chlorophyll content, free proline content in the leaves, gas exchange, water potential in the branch, and soil moisture were evaluated. The data were submitted for analysis of variance and regression at the 5% probability level, using the Sisvar program. We observed that the analyzed pomegranate can avoid excessive water loss to the atmosphere when subjected to water stress using different mechanisms. Moreover, the deficit of irrigation depths led to an anticipation and/or uniformity of flowering.

Profitability and efficiency of conduction systems and optimal tomato density for fresh consumption

2022-08-02T21:11:08-03:00

This study evaluated the productivity and economic profitability of cultivation systems for the table market. A hybrid tomato cultivar, Fascínio was grown in 12 cultivation systems of the “half stake”, “open V”, and “low” types, with four spacings–0.2, 0.3, 0.4, and 0.5 m between plants and 1.5 m between rows. Eleven fruits were harvested at the mature stage, and the productive (total, commercial, and non-commercial productivity, percentage of losses, and types of damage) and economic (production cost, revenue, and profit) parameters were evaluated. The half-stake and low (both with 0.2 m spacing) cropping systems showed the highest total yields (179 t ha^-1), differing from the open V (154.4 t ha^-1) and half-stake (0.2 m spacing) systems at higher commercial productivity (158.1 t ha^-1). With a production cost below 100 thousand R$ per hectare and a profitability index above 58%, the half-stake and low (0.2 m spacing) cultivation systems proved to be more productive and economically efficient than the open V system, fulfilling the requirements of tomato growers. The creeping system (0.2 m spacing) had the highest percentage of losses (22%) due to non-marketable fruits; Based on damage nature, the half-stake system tomatoes showed black backgrounds and the open and creeping systems showed tomato locules affected by pests.

Agronomic performance and fruit sensory and quality analyses of pineapple cultivars

2023-08-05T09:03:59-03:00

The objective of this study was to assess the agronomic performance and fruit sensory and quality characteristics in traditional and modern pineapple cultivars grown in Tangara da Serra, MT, Brazil. The experiment was conducted in a randomized block design, with five replications and 20 plants per plot. Planting was carried out in double rows with spacing of 1.2×0.4×0.4 m, in May 2018. The evaluated cultivars were BRS-Ajuba, BRS-Imperial, BRS-Vitoria, Gigante-de-Tarauaca, IAC-Fantastico, Jupi, Perola, and Smooth-Cayenne. Gigante-de-Tarauaca exhibited the highest fruit weight but presented low soluble solids content and soluble solids to titratable acidity ratio (SS/TA); thus, it is not recommended for fresh fruit market. Jupi exhibited fruit weights (>1500 g) suitable for the market and soluble solids above 12 °Brix, but SS/TA below 20. Considering the modern cultivars, BRS-Ajuba presented the highest fruit weight, but BRS-Imperial and IAC-Fantastico were the most attractive to consumers, as well as the traditional cultivar Perola. However, BRS-Imperial and IAC-Fantastico yield small fruits, which reduces their per-unit value in the market, as pineapples are typically valued based on their sizes.

Biocontrol agents against Penicillium digitatum in 'pera' orange

2023-03-21T19:30:35-03:00

This work aimed to evaluate the efficiency of biocontrol agents in controlling green mold (Penicillium digitatum) in 'pera' orange fruits. In vitro experiments were carried out with a fungus isolate grown on BDA medium and tested against different concentrations of commercial products based on biocontrol agents: Trichoderma harzianum (0, 5, 10, 15, 20 and 25 mL L ^-1), Bacillus subtilis (0, 2, 4, 6, 8 and 10 mL L ^-1) and B. licheniformis + B. subtilis + T. longibrachiatum (0, 5, 10, 15, 20 and 25 g L ^-1) and the fungicide imazalil as standard (2 mL L ^-1). The experiment analyzed mycelial growth and spore germination. Based on the results, in vivo tests were carried out, evaluating the curative and preventive effect of applying biocontrol agents as inoculating with 10 µL of conidial suspension (10⁸ conidia mL^-1). All biochemical agents displayed 100% control over mycelial growth and a linear effect to inhibit the germination of P. digitatum. The in vivo tests highlighted that all agents showed a linear effect, both in the curative and preventive effects, significantly reducing the development of green mold (AUDPC) in 'pera' orange fruits. The experiment concludes that the prophylactic application of 25 mL L ^-1of T. harzianum, 10 mL L ^-1of B. subtilis, and 25 g L ^-1of B. licheniformis + B. subtilis + T. longibrachiatum in orange fruits 'pera' control P. digitatum.

Response of Jabuticaba [Plinia cauliflora (Mart) Kausel] seedlings to herbicides

2023-10-08T12:15:26-03:00

Jabuticaba (Plinia sp.) is one of the most important fruit species in the Brazilian flora; it is appreciated for fresh consumption or products produced from its fruits. The establishing of orchards requires the determination of management methods that favor the development and productivity of this species. The objective of this work was to evaluate the response of jabuticaba seedlings to application of herbicides and determine possible phytotoxicity. The experiment was conducted at the Federal Technological University of Paraná, in Dois Vizinhos, PR, Brazil. A randomized block experimental design with four replications was used, with 5 plants per experimental unit. The treatments consisted of applications of pre-emergence herbicides (Dual Gold® and Spider®) and post-emergence herbicides (2,4-D, Ally®, Enlist®, Primatop®, Fusilade®, Imazetapyr, Flex®, Plenum®, and Volcane®). The applied herbicide rates were equivalent to 50% of their commercial recommendation. A spray volume equivalent to 250 L ha-1 was applied, using water as diluent. The following parameters were evaluated 45 days after applications: stem diameter at 1 cm above ground (cm); plant height (cm); numbers of necrotic, chlorotic, shriveled, and healthy leaves; number and length of shoots (cm); survival rate (%); and chlorophyll contents (a, b, and total). The application of the herbicides Ally®, Enlist®, and Flex® resulted in less harmful effects on jabuticaba seedlings. The lowest survival rates were found in plants in the treatments with the herbicides Dual Gold®, Volcane®, and Primatop®.

Production performance of Hylocereus polyrhizus based on cladode size and position

2020-08-13T18:51:12-03:00

The analysis of productive architecture of plants involves macroscopic observation of spatial distributions of different vegetative and reproductive organs. However, few studies have evaluated these aspects in dragon fruit plants for production purposes. The objective of this study was to evaluate vegetative, reproductive, and quality parameters of dragon fruit plants (Hylocereus polyrhizus; variety Cebra) based on the position and size of cladodes, considering morphological, production, and quality characteristics of the fruits. The experiment was conducted from September 2016 to May 2018, using a completely randomized design in a 3×4 factorial arrangement, consisted of three positions of cladode insertion in the plant (primary, secondary, and tertiary) and four different cladode sizes (≤ 20 cm; 21-40 cm; 41-60 cm, and 61-80 cm), with five replications and six cladodes per plot, totaling 360 evaluated cladodes. According to the results, vegetative and reproductive characteristics of dragon fruit plants variety Cebra were affected by the cladode position and size. Fruits developed on primary cladodes with sizes of 21 to 40 cm presented, in general, better-quality characteristics. All evaluated physical and physicochemical characteristics were affected by the cladode position and size, except for titratable acidity and soluble solids to titratable acidity ratio. Fruits developed on cladodes smaller than 20 cm had lower quality. Therefore, maintaining and promoting the growth of primary cladodes with sizes of 21 to 40 cm and removing those smaller than 20 cm is recommended.

Detection Of Sm Gene Resistance To Gray Leaf Spot In (Stemphylium Spp.) Tomato Cultivars Iraq

2023-08-02T11:13:19-03:00

Abstract

Gray leaf spot, Occurs due to Stemphylium spp., is a foliar disease in tomato. The Resistance against gray leaf spot disease is conferred by a single incompletely dominant gene Sm located on chromosome 11. This study aimed to identify cultivar resistant alleles or susceptible alleles by molecular marker tightly linked to the Sm gene and the use of marker-assisted selection inbreeding. In this study, we used eight tomato cultivars Farmed in Iraq. The analysis demonstrated that the co-dominant marker Sm-InDel, which produced 122-bp fragment for resistance in seven genotypes and a 140-bp fragment for susceptible alleles in one genotype, respectively could be utilized in Marker-assisted selection (MAS)for gray leaf spot resistance.

Physiology and development of grafted dwarf cashew seedlings under different fertilization doses and irrigated with saline water

2023-08-02T11:00:52-03:00

Salinity is one of the primary challenges faced by irrigated agriculture in semi-arid regions. This study aimed to investigate the effects of fertilization on the development of cashew seedlings irrigated with water of varying salinity levels. The research was conducted in a protected environment at Embrapa Agroindústria Tropical, Fortaleza, using grafted seedlings of the BRS 189 clone on CCP 06 rootstock. The treatments resulted from the combination of three levels of NPK fertilization (control - without fertilization, 50% less than conventional nutrition, and 100% of conventional nutrition used by the crop), which was incorporated into the substrate before sowing CCP 06, with four salinity levels (ECa of 0.8, 4.0, 7.0, and 10.0 dS m^-1) of the irrigation water for the seedlings. Gas exchange, assimilate accumulation, growth, and nutrient content in the leaves, stems, and roots of the seedlings were evaluated 90 days after grafting. The data were subjected to analysis of variance, and when a significant effect was observed, the Tukey test was performed, while quantitative data were subjected to regression analysis. Overall, fertilization levels did not influence seedling growth. Fertilization did not interfere with photosynthate production, which performed better when the seedlings were subjected to a salinity of 7.0 dS m^-1. The application of NPK to the substrate resulted in higher levels of nitrogen in the leaves, while phosphorus content decreased, and foliar potassium was not influenced by fertilization.

Air assistance and spray volumes on the coverage, droplet density, and spray deposition in melon plants

2023-02-06T17:55:09-03:00

This study aimed to evaluate the influence of air assistance on the coverage, droplet density, and deposition of the mixture volume applied to melon plants. The experiment was conducted in a completely randomized design set up in a 4 x 4 x 2 factorial arrangement referring to four spray nozzles (AVI 110-02, TT 110-02, AVI 110-03, and TT 110-03), four mixture volumes (140, 200, 300, and 400 L ha^-1), and two application techniques (with and without air assistance), at a constant working pressure of 300 kPa. Deposition analysis was performed by using a bright blue dye, and the coverage pattern and droplet density were analyzed using water-sensitive paper tags attached to the adaxial and abaxial surfaces of the leaf blade of melon plants. Air assistance in the spray boom improved the deposition of the mixture sprayed on melon leaves only when using nozzle TT 110-02, whereas nozzles TT 110-03, AVI 110-02, and AVI 110-03 were not influenced by air assistance. Coverage and spray deposition on the adaxial leaf surface increased with the mixture volume applied for all nozzles. The technique using water-sensitive tags is not efficient to evaluate droplet density when working with high spray volumes.

Tolerance of pineapple cultivars to natural flowering induction in the state of Mato Grosso

2022-12-14T14:12:01-03:00

Natural flowering in pineapple crops can cause significant economic losses to growers, resulting in uneven fruiting, which hinders phytosanitary operations and the scaling of fruit harvest. The objective of this work was to evaluate the tolerance of eight pineapple cultivars to natural flowering induction in Tangara da Serra, Mato Grosso, Brazil. The cultivars BRS-Ajuba, BRS-Imperial, BRS-Vitoria, Gigante-de-Tarauaca, IAC-Fantastico, Jupi, Perola, and Smooth-Cayenne were evaluated. Planting was carried out in May of 2018, in a randomized block design, with five replications and 20 plants per plot. Plant height, D-leaf length, and percentage of induced plants were evaluated. The surveying period of plants naturally induced was between May and September 2019. In this period, the plants were between 12 and 16 months of age, with adequate D-leaf lengths and plant heights for the occurrence of flowering induction. There were days with night-time temperatures below 15 °C; the lowest photoperiod was in June. The cultivars Smooth-Cayenne, BRS-Imperial, and IAC-Fantastico were tolerant to the natural induction, which resulted in uneven fruiting, causing losses to growers.

Do sub-doses of glyphosate and 2,4-D cause hormesis in the pineapple plants? Insights into the response of the pineapple plants to this phenomenon

2023-08-22T12:48:04-03:00

The slow growth of the pineapple (Ananas comosus (L.) Merr.) during the vegetative phase prolongs the crop cycle, resulting in higher production costs. When used in low doses, some herbicides can stimulate plant growth, a phenomenon known as hormesis. The aim of this study was to determine the effects of sub-doses of glyphosate and 2,4-dichlorophenoxyacetic acid (2,4-D) on growth in the Pérola cultivar of the pineapple. The treatments under study consisted of glyphosate applications of 0, 1.8, 3.6, 7.2, 18, 36, 72, 180, 360 and 720 g a.e. ha^-1, and 2,4-D applications of 0, 1.68, 3.35, 6.70, 16.75, 33.5, 67, 167.5, 335 and 670 g a.e. ha^-1. The experiments were completely randomised with four replications. The plants were grown in the greenhouse in pots with a capacity of 8 dm³ substrate. Growth variables were evaluated in the plants, together with the total and partitioned accumulated biomass (leaf, stem and root). The data were submitted to analysis of variance and regression. The pineapple showed greater phytotoxicity from the glyphosate herbicide at applications ranging from 18 to 720 g a.e. ha^-1 and from 2,4-D in the range of 167.5 to 670 g a.e. ha^-1. The hormesis effect was evidenced by the 32.25% increase in root fresh weight at the dose of 1.8 g a.e. ha^-1 glyphosate. However, the slow growth of the pineapple was not overcome by the hormesis effect of the herbicides.

Production of desert rose seedlings under different cultivation techniques

2022-12-13T21:56:29-03:00

Desert roses have gained notoriety in the ornamental market; however, the use of locally produced substrates is
diverse. Three experiments were carried out using a completely randomized design, with treatments arranged in
a 3x4 factorial. Physical and chemical analyses were carried out for the following substrates: carnauba bagana,
carbonized rice husk, decomposed babassu stem, and soil. Experiment 1: three sowing depths, D1: 0mm, D2:
5mm and D3: 10 mm, combined with four substrates. Experiment 2: three substrates combined with four shading
screens: thermal reflector, white shading, black shading and open sky. Experiment 3: three substrates combined with four irrigation levels: 100, 75, 50, and 25%. Measurements were made in the three experiments and data
were tested by analysis of variance using the “F” test, at the levels of 1% and 5%. Regression and averages were
explored using Tukey’s test. It was concluded that the seedlings developed better under a level of 10 mm and
substrate with 100% carnauba bagana, in association with an outdoor environment, and water levels between
50 and 75% of pot capacity.

O Organic substrates in the development of camu-camuzeiro (Myrciaria dubia (H. B. K.) McVaugh) in the amazon region

2023-08-05T09:06:34-03:00

Amazon is the largest tropical forest on the planet, it has a variety of plant species with emphasis on many
fruit trees, such as the camu-camuzeiro (Myrciaria dubia (H. B. K.) McVaugh), which occurs naturally on the
banks of rivers, lakes, lowlands and flooded forest of the Amazon. The objective of this study is to evaluate the
development of camu-camuzeiro seedlings in different organic substrates. The experiment was conducted
in the seedling production nursery of the Federal Rural University of Amazon. The experimental design was
entirely randomized, with ten treatments and five repetitions, each portion was represented by ten plants,
totaling 500 seedlings. The substrates evaluated were: T1 - Humus; T2 - Humus + Bird manure; T3 - Humus + Bovine
manure; T4 - Humus + Açaí kernel; T5 - Humus + Chestnut shell; T6 - Humus + Chestnut shell + Poultry manure;
T7 - Humus + Bovine manure + Chestnut shell; T8 - Humus + Açaí kernel + Poultry manure; T9 - Humus + Açaí
kernel + Bovine manure; T10 - Commercial. The different substrates used influenced the development of camucamuzeiro
seedlings evaluated at 180 days. The treatments with a substrate based on Humus (T1), Humus + Açaí
kernel (T4), Humus + Chestnut shell (T5), Humus + Chestnut shell + Poultry manure (T6), Humus + Bovine manure +
Chestnut shell (T7), Humus + Açaí Kernel + Bovine manure (T9) and the commercial substrate (T10) are the best
for a satisfactory development of this crop in the production field.

Agrophysiology, biochemical, and yielding characteristics of Chinese cabbage due to formulations and concentrations of nutrient in hydroponic

2023-05-02T18:44:49-03:00

Hydroponic solution from agricultural organic waste can be used as an alternative to chemical solutions and
strongly increases the growth and yield of Chinese cabbage plants. This study was to obtain formulations,
concentrations, and their interactions that have the potential to increase the agronomic, physiological,
biochemical, and yielding characteristics of Chinese cabbage in hydroponic culture. This study was conducted
from September to November 2022 using a randomized block design with two factors and three replications.
The first factor was the formulation of organic nutrient solutions (F1= banana peels+bean sprouts+eggshells; F2=
banana humps+onion peels+bean sprouts+moringa leaves; F3= moringa leaves+onion peels+bean sprouts; F4=
AB mix as a comparison). The second factor was the concentrations (600; 900; 1,200; 1,500 ppm). Data were
analyzed using ANOVA and proceeded with the Duncan at P<0.05. The results showed that formulations F3 and
F2 significantly increased Mg and chlorophyll b levels while formulation F1 increased nitrate and flavonoids. The
concentrations ranged from 1,200 to 1,500 ppm showed the highest yield and shoot fresh weight were 2.86 kg
m^-2 year^-1 and 30.70 g. The F3C4 interaction was highly recommended to increase the yield of Chinese cabbage
by 2.68 kg m^-2 year^-1 compared to the other liquid organic fertilizers and it could be used as a substitute for using
liquid chemical fertilizers in hydroponic culture.

Effects of plant biostimulants and plant growth regulator applications on plant growth in lilium 'Adelante'

2023-05-08T14:59:18-03:00

This experiment was designed, it was determined the effects of mycorrhiza, vermicompost, promalin applications on development of plant properties in a bulbous plant, Lilyum 'Adelante. Flower branch length (cm), flower branch diameter (mm), internode number, flower bud number, flower bud length (cm), flower stem length (cm), flower width (cm), flower length (cm), number of leaves and leaf length (cm) were measured. The results showed that no treatment increased plant height more than control plants, but each application had different effects on other plant characteristics. As a matter of fact, mycorrhiza increased internode number, flower bud number, flower bud length, flower stem length, flower length, number of leaves and leaf length by 6.3%, 15.6%, 14.2%, 6%, 40%, 10.3%, 2.9% and 6%, respectively. Vermicompost increased flower bud length, flower length and leaf length by 6.6, 12, 15.3% and 16.1%, respectively. Promalin, on the other hand, increased the flower stem length, flower length and leaf length by 56.3% and 15.4%, respectively. The application of mycorrhiza together with Promalin did not have a different effect than the application of Promalin alone, and even showed a lower effect than the application of Promalin alone. Mycorrhiza, on the other hand, was the application that showed the best effect compared to other applications. Therefore, it can be recommended for plant growth in lilies. However, due to the effect of application time and dose on flowering time, it is possible to obtain different results in plant development in lilies.

Yield of Syn-1 synthetic varieties of tropical onion resulting from openpollinated Brazilian populations

2023-03-21T18:30:39-03:00

Due to technological limitations for the development of onion hybrids, first-cycle synthetic varieties (Syn1-
SV) could be an alternative to partially explore heterotic vigor. The growing areas of onion hybrids in Brazil
are mainly defined by bulb yield and uniformity. From this perspective, the present study aimed to develop
tropical onion Syn1-SV and estimate mid-parent heterosis (Hm), heterobeltiosis (Hp), and standard heterosis
(Hs) as an alternative to hybrid development. Six Syn1-SVs, eight open-pollinated (OP) populations, and one
commercial hybrid were evaluated in a randomized block design with three replications, in two semesters, for
the commercial bulb yield (CBY) and days to bulb harvest (DBH). Significant differences were observed for
treatments (T), semesters (S) and the T*S interaction for both variables (p-value<0.05). The OPs ‘Alfa SF RT’ in
the first semester and ‘IPA11’ in the second semester were the most precocious treatments. The highest CBY
was estimated in the commercial hybrid (105.8 t ha-1) and in ‘Alfa SF RT’ (45.5 t ha-1) in the first and second
semesters, respectively. Three Syn1-SVs showed positive Hm values, ranging from 2.0% to 6.3% for CBY. Three
Syn1-SV showed positive Hp values in the first semester, ranging from 3.0% to 5.2%, for CBY. Only the Syn1-SV ‘Alfa
SF RT’ × ‘BRS Alfa São Francisco’ (48.9 t ha-1) showed positive Hs values, surpassing by a small value the control
OP population ‘IPA11’ (48.0 t ha-1), indicating the potential of Syn1-SV as an option for onion hybrids.

Agronomic efficiency of organomineral fertilizer in onion cultivation

2022-12-14T15:00:01-03:00

Onions has high nutritional and nutraceutical value. In the last decade the bulbs have gained increasing
relevance due their compounds linked to anti-cancer effects. The fertilization managment is relevant to this
crop because the mineral’s influence beyond productivity, interfering in several aspects of quality. Organic
sources despite available, adoption is still cautious and seen as an expense, rather than investment in soil
quality. Therefore, the objective was to evaluate the use of organomineral fertilizer on the development and
productivity of Akamaru hybrid. The experiment was carried out in Cristalina-GO, in a randomized block design,
with 4 replications and 5 treatments: organomineral fertilizer (NPK) with the formula 02-20-05. The rates were
adjusted to approximately the same amounts, where 3,680 kg ha^-1 was considered the 100% rate, 2,944 kg ha^-1
as 80%, 2,208 kg ha^-1 as 60% and 1,472 kg ha^-1 as 40% of the rate established. The rate of 2,300 kg ha^-1 of the
formulated 03-35-06 referred to 100% of the mineral source. The total yield of onion was not affected when the
organomineral source was used, therefore, it is a viable source for use in onion culture. A rate reduction of up
to 20% of the recommended mineral rate allows good performance (85.5 t ha^-1), with 7.5 t ha^-1 higher than the
60% reduction of the recommended rate.

NPK combinations mitigate the deleterious effects of salt stress on the morphophysiology of West Indian Cherry

2022-12-14T14:44:49-03:00

Under salt stress, plant growth and development are negatively affected due to physiological changes,
requiring strategies such as fertilization management to minimize these effects. In this scenario, this study aimed
to evaluate the effect of combinations of nitrogen, phosphorus, and potassium on the growth, leaf water
status, electrolyte leakage, and gas exchange of West Indian Cherry grown under water stress in the second
year of production. The experiment was conducted in a protected environment in Campina Grande - PB.
The treatments were distributed in a randomized block design with a 2 × 10 factorial arrangement with three
replications corresponding to two electrical conductivity levels of irrigation water– ECw (0.6 and 4.0 dS m^-1)
and ten combinations of fertilization with nitrogen, phosphorus, and potassium (80-100-100; 100-100-100; 120-
100-100; 140-100-100; 100-80-100; 100-120-100; 100-140-100; 100-100-80; 100-100-120, and 100-100-140% of the
recommendation in the second year of production). Irrigation with the ECw of 4.0 dS m-1 negatively affected
plant growth, the leaf water status, electrolyte leakage, and the leaf gas exchange of West Indian Cherry.
However, the 40% increase (C4 -140-100-100% of the recommended N-P₂O₅-K₂O level) in the nitrogen level
mitigated the deleterious effects of salt stress on the relative water content, internal CO₂ concentration, and the
CO₂ assimilation rate of West Indian Cherry plants in the second year of production.

Organomineral as a substitute for mineral fertilization in potato cultivation

2022-12-14T14:41:39-03:00

Potato (Solanum tuberosum, L.) is one of the most responsive crops to fertilizer application, which drives the
need to rationalize and make the most of nutritional resources in efficient and sustainable management. Based
on the hypothesis that the organomineral is a great alternative to increase potato productivity (Ágata and
Atlantic cultivars) and that it can be indicated as a substitute for mineral fertilizers, this study aims to evaluate
the effect of organomineral doses applied in the planting furrow on potato productivity to identify the best
level of mineral fertilizer replacement. A study was conducted in the city of Cristalina (state of Goiás, Brazil),
evaluating the replacement of 40, 60, 80, and 100% of mineral fertilizer (standard) provided via organomineral
fertilizer in two widely cultivated varieties. The total productivity and the productivity in classes were monitored,
as well as the nutrient contents in the leaves. The results showed that the organomineral is a great alternative to
increase potato productivity and can be indicated as a substitute for mineral fertilizers. For the cultivar Ágata,
an organomineral dose of 80% is recommended concerning mineral fertilization. On the other hand, for the
Atlantic cultivar, the same dose of mineral fertilizer is recommended. In both cultivars, there was an increase in
tuber size with organomineral fertilization, which indicates greater efficiency in tuber productivity.

Floral, reproductive, and pollination biology of Floral, reproductive, and pollination biology of Eugenia myrcianthes Nied.

2023-08-02T11:21:20-03:00

Studies on species of the family Myrtaceae are mostly related to floristic surveys, reproduction involving large plant communities, and family taxonomy. Thus, the objective of this study was to elucidate aspects of the floral and reproductive biology, as well as floral visitors of ubajai (Eugenia myrcianthes Nied.). Studies were conducted on floral morphology and morphometry, identification of nectaries and structures attractive to floral visitors, characterization of floral visitors, stigma receptivity, and androecium maturation, pollen storage, in vitro viability testing, and characterization of the reproductive system. Ubajai flowers open at approximately 6:00 a.m., and their anthers are the main attractive structure to floral visitors. The main floral visitors and effective pollinators of ubajai are honeybees (Apis mellifera). The addition of 40% sucrose to the culture medium, using fresh pre-anthesis pollen, allows for a 90% germination rate. Ubajai pollen is recalcitrant, thus, it loses viability before 30 days of storage, even when stored in a refrigerator, freezer, liquid nitrogen, or natural environment. Ubajai can be considered a self-compatible plant; however, fertilization of flowers through cross-pollination also occurs, and apomixis does not occur.

Native bacteria from the caatinga biome mitigate the effects of drought on melon (Cucumis melo L.)

2022-12-13T21:42:40-03:00

Plant growth-promoting bacteria (PGPB) from drylands are promising biological resources to mitigate the
negative effects induced by water deficit. The aim of this study was to evaluate the effects of bacteria native
from the Caatinga biome on the initial growth of melon plants subjected to water deficit. Nine bacteria (M1.1,
T11.2, PH5.2, T11.1, T2.1, T1.1, M7.1, XX6.9 and XX6.6) isolated from Caatinga soils were tested in two varieties
of melons (Cantaloupe and Yellow) cultivated under two water availability scenarios (50% irrigation and 100%
irrigation of the crop evapotranspiration - ETc). In the control treatment, no inoculation was performed. The
effects of the treatments on shoot length (SL), shoot dry mass (SDM), root length (RL) and root dry mass (RDM)
were evaluated. In the scenario without water deficit (100% ETc replacement), the isolates PH5.2, T2.2, M7.1,
XX6.9 promoted (p<0.05) the root and shoot biomasses in the Cantaloupe variety, while in the Yellow variety,
growth promotion was sporadic, with three isolates (M1.1, M7.1 and XX6.9) promoting at least one parameter
evaluated. In the scenario with a water deficit (50% ETc replacement), isolates T1.1 and XX6.9 promoted the
total biomasses (SDM and RDM) of the Cantaloupe and Yellow varieties, respectively. All isolates stimulated RL in
the Cantaloupe variety. Bacteria isolated from the Caatinga promote growth and reduce the effects of water
deficit in melon and thus are potential inoculants to enhance production in the early stages of melon cultivation
in semiarid regions.

Organic fertilizer doses for top-dressing fertilization in jambu (Acmella oleracea [(L.) R. K. Jansen]) production

2022-12-13T19:01:34-03:00

Due to the lack of specific fertilization recommendations for jambu cultivation, producers commonly use
fertilizers recommended for other vegetables. This study aimed to evaluate the effect of different doses of
organic fertilizers, namely hoof and horn powder and castor bean cake, on jambu plant production under an
organic system. The experiments were conducted at the Experimental Farm of São Manuel, SP, belonging to the
School of Agriculture (FCA) – UNESP, and at the “Estância Três Nascentes” site, located in Botucatu, SP, Brazil.
Twelve treatments were evaluated, in a 2 x 6 factorial design, consisting of two organic fertilizers (castor bean
cake (CBC) and hoof and horn powder (HHP)) x 6 top dressing N doses (50, 75, 100, 125, 150, and 0 (control
without these fertilizers)). The experimental design was a randomized block with four replications. Plant height
(PH), number of inflorescences (NI), the fresh weight of inflorescence (FWI), the fresh weight of vegetative parts
(FWVP), and the total fresh weight (TFW) were evaluated at each location. Linear increases were observed in all
characteristics in both locations as the fertilizer doses increased. Comparing the highest dose (150 kg ha-1 of N)
with the control, increases of 109%, 251%, 218%, 283%, and 227% were obtained at the farm in São Manuel, and
69%, 79%, 111%, 276%, and 118% in Botucatu, for PH, NI, FWVP, FWI, and TFW, respectively. When comparing the
two fertilizers, HHP presented better results than CBC for most characteristics in both areas.

Gladiolus production as a function of growing environment conditions: a scientometric analysis

2022-12-13T18:26:49-03:00

Lately, an increase in the commercialization of gladiolus has been observed, making it necessary to know information that contributes to the optimization of its production. Such information can be obtained from the scientometric analysis. Thus, the objective of this work was to perform a scientometric analysis of the global scientific literature to quantify the studies on gladiolus and to specify in the Brazilian scientific literature the results
of works on the cultivation environment. The scientometric analysis was performed in the Scopus database for the entire historical data series until the year 2021. A total of 1402 scientific papers published on gladiolus culture were obtained with an average publication rate equal to 0.62 papers year^-1. These papers were mostly
published as scientific articles in English language in journals focusing on horticulture and India is the country
with the highest number of publications. About the cultivation environment, the studies conducted in Brazil indicate that the production of gladiolus should be carried out in periods that do not occur frosts and also for average air temperature below 35°C and soil humidity above 75% of field capacity. Despite the important results of these works, the global scientific literature still lacks more information that adequately assists in the increase of gladiolus production.

Physicochemical and functional characteristics of peach cv. Esmeralda fertilized with different doses of nitrogen

2023-05-02T09:38:11-03:00

The aim of this study was to evaluate the physicochemical and functional characteristics of fruits yielded by
peach trees which were fertilized with different doses of nitrogen. The experiment, which was installed in 2014.
It had a randomized complete block design with four replicates. The nitrogen rates applied were 0, 40, 80,
120, and 160 kg N per hectare. Fruits were harvested in four crops in a row (2014, 2015, 2016, and 2017). The
parameters were evaluated: soluble solids, pH, titratable acidity, epidermis and pulp firmness, attributes of pulp
color, carotenoids, phenolic compounds, and antioxidant activity. Responses were only related to luminosity in
the first crop. However, N fertilization influenced not only the soluble solid content, pH and chroma in the second
crop but also all attributes of color in the third crop. SS, pH, ºHue and chroma differed among treatments in
the fourth crop. The more N in the first three crops, the more carotenoids. Phenolic compounds decreased
significantly in the 2016 crop whereas antioxidant activity diminished in both the 2015 and 2016 crops. Even
though an ideal dose of N cannot be recommended due to high variation in attributes in the years under
evaluation, it is needed because of other factors, such as weat her.