Comunicata Scientiae

Biofertilizers in horticultural crops

2020-01-01T15:34:43+00:00

Bovine manure biofertilizers can exert physical, chemical, and biological effects on the soil and the phytoprotective, physiological, and productive actions in horticultural crops. The literature review was performed to compile information on the production, uses, and effects of bovine manure biofertilizers on soil properties and plants. Biofertilizers are produced by organic components, minerals, and inoculants. Among the organic sources, the bovine manure is the most used. The fermentation of the bovine manure in water constitutes the Vairo biofertilizer, the most employed in Brazilian horticulture. With the chemical enrichment of this preparation came the Supermagro, Agrobio, and Agrobom biofertilizers. In the soil, it can act in the improvement of soil fertility, physical properties, and in the diversity and abundance of the biota. Also, it can act in control of pests and diseases, leaf composition concerning macro and micronutrients, and in the production and post-harvest quality of horticultural crops. Therefore, this review describes the preparation, chemical composition, and utilization of bovine manure biofertilizers in both soil and plants, offering perspectives of research on the formulations, application, and effects of these inputs on horticultural species.

Response of essential-oil yield of aromatic and medicinal plants to different harvesting strategies

2019-12-31T21:16:29+00:00

The demand for aromatic and medicinal plants (AMPs) is growing worldwide, and most of them are from the wild collection. Today there is a consensus that for industrial purposes the AMPs must be cultivated. Many studies have shown the importance of the collection strategy used to guarantee the plant regeneration, and soil protection against erosion process in mountainous areas in the Mediterranean region. In this work, during three-year monitoring period we compared in four AMPs two harvest strategies by cutting biomass in 25% (BHI25) and 50% (BHI50) of oregano (Origanum bastetanum L.), lavender (Lavandula lanata L.); sage (Salvia lavandulifolia V.); and santolina (Santolina rosmarinifolia L.) in order to assess their effect on essential-oil content, and to be consistent with both plant and soil conservation in Mediterranean steeply sloping areas. The experimental plots were located in Lanjarón (Granada, SE Spain), on a 20% slope. According to the findings the strategy BHI50 of fresh herb of oregano, lavender, sage, and santolina produced essential-oil yield of 13.2 ± 1.74, 17.3 ± 1.69, 9.7 ± 5.21, and 10.8 ± 2.00 L·ha-1, respectively. Since significant differences were found between BHI25 and BHI50 strategies for harvest and distillation of aromatic plants, we recommend a rational harvest, leaving the 50% of the plant biomass in the field to avoid the soil degradation. In addition, with this rational harvest strategy encourages the sustainable AMP cultivation without significant alterations for essential-oil yields, and at the same time guaranteeing the regrowth, and conservation of them in its habitat. Therefore, encouragement local decision-making measures regarding environmental compatibility, social acceptability and economic viability in land use and management will be crucial. Otherwise, the inappropriate harvest of aromatic shrubs in mountain areas compromises land conservation.

Nodal segments and zygotic embryos in culture media for the in vitro propagation of tamarind

2019-12-31T21:27:41+00:00

There has been a lack of research on the propagation methods of tamarind, hindering the availability and supply of its products. Considering the nutraceutical potential of tamarind and the long-time required to initiate production, this study aimed to evaluate the establishment of nodal segments and the germination of in vitro zygotic embryos of tamarind plants in culture media, salt concentrations, and activated charcoal, aiming at the establishment of an in vitro propagation protocol. For this purpose, MS and WPM media with 25, 50, 75 and 100% salt concentrations were used both with and without activated charcoal (2 g L-1) for the inoculation of nodal segments and zygotic embryos of tamarind. The experiment was conducted in a completely randomized experimental design, in a 2 x 4 x 2 factorial scheme (culture media x salt concentrations x activated charcoal) with 20 replications. It was observed that the in vitro establishment of tamarind nodal segments is viable when using the MS medium with 75% of salts plus 2 g L-1 of activated charcoal and that for the germination of zygotic embryos there was no influence of the treatments. It was also observed that in order to increase the length of the formed plantlets, the MS and WPM media can be employed with 75% of salts.

Propagation of yellow mombin by stem and root cuttings treated with indolebutyric acid

2019-12-31T21:54:04+00:00

Yellow mombin is a fruit species of growing interest in the agro-industrial sector, mainly in the North and Northeast regions of Brazil, although its commercial exploitation is still limited due to the lack of information regarding its propagation, among other factors. In this perspective, this work aimed to study the effect of the application of indolebutyric acid (IBA) in the vegetative propagation of yellow mombin by stem and root cuttings. The experiments were conducted in a plant nursery, under a completely randomized experimental design consisting of six concentrations of IBA (0, 1000, 2000, 3000, 4000 and 5000 mg.kg-1 in industrial talc), four replications, and ten cuttings per plot. The stem cutting experiment also evaluated the effect of the types of cuttings (tanchan, basal, stratified basal, medial, and apical), with the material being collected from a yellow mombin tree in full vegetative growth. The root cuttings were collected from a matrix plant in the stage of vegetative rest and cut into 15 cm length segments. After 120 days, the following variables were evaluated: percentage of living, sprouted, rooted, and calloused cuttings, and dry mass of roots and sprouts. The cuttings of the tanchan type showed higher survival and sprouting percentages, regardless of the concentration of IBA applied, whereas the rooting rate was low. The application of IBA increased the rooting percentage of the root cuttings until the maximum concentration of 5000 mg.kg-1, reaching 77.5%, although it did not influence the other variables analyzed. The root cuttings of yellow mombin exhibit good regeneration capacity.

Maturation and physiological quality of IAC-863 Rangpur lime seeds

2019-12-31T21:59:58+00:00

There is a growing demand for high quality seeds to obtain citrus rootstocks. Normative Instruction 48 (MAPA) of September 24, 2013, requires minimum of 50% germination for the marketing of citrus seeds. Harvest season is one of the stages of seed production with great importance to ensure quality, which makes knowing its maturation process an important step. Thus, the objective of this study was to monitor physicochemical changes in IAC-863 Rangpur lime fruits in order to characterize the physiological maturity of seeds, and to define the ideal harvest point in order to obtain seeds with high physiological quality to obtain rootstocks. Physicochemical analysis of fruits (mass loss, color, soluble solids and acidity) and analysis of seeds (water content, germination and emergence) was performed. Higher germination results were observed in seeds obtained from fruits with higher color index and soluble solids content. The storage of IAC-863 Rangpur lime fruits after harvest increases germination rate, especially in mid-season fruits.

Physiological quality of citrandarins, Poncirus trifoliata and Sunki mandarin seeds

2019-12-31T21:36:35+00:00

Rangpur lime is the rootstock most used in Brazil, mainly due to its resistance to drought; however, it is susceptible to several diseases, requiring the search for other rootstocks tolerant to factors limiting citrus cultivation. In addition, the Brazilian legislation stipulates that citrus seeds can only be commercialized with at least 50% germination rate. Thus, the aim of this work was to evaluate the physiological quality of seeds of seven citrus rootstocks. The following citrus fruits were harvested: Poncirus trifoliata, Sunki mandarin and their hybrids –citrandarins (70, 106, 254, 299 and 310). Fruit mass, diameter and height were measured. Seeds were extracted from fruits, counting the number of normal seeds (not aborted). Seeds were dried up to 20% water content and stored for 3, 6, 9 and 12 months. The physiological quality of seeds was evaluated before storage (time 0) up to 12 months of storage. The quality of Poncirus trifoliata, Sunki mandarin and citrandarins 70, 106, 254, 299 and 310 seeds was reduced during storage. However, their germination rate remained above 50%, evidencing that seeds of all rootstocks could be marketed until 12 months of storage. The new rootstocks tested have seeds with physiological quality compatible with their parents, in compliance with current legislation.

Growth and nutrient accumulation in three peach rootstocks until the grafting stage

2019-12-31T21:46:20+00:00

Analysing growth and nutrient accumulation is generally employed for guiding the fertilisation practices in the seedling-production chain. In the production of peach rootstock, such evaluations can provide information to aid can to aid in discrimination available genotypes, especially regarding the efficient use and conversion of fertiliser into dry matter, which can reduce the time required to obtain plants suitable for grafting. The aim of this study, was to investigate the differences in growth and nutrient accumulation in three peach-rootstock cultivars. A completely randomised experimental design was used, in a 3 x 4 factorial scheme, including three peach rootstocks ('Flordaguard', 'Capdeboscq' and 'Okinawa Roxo') and four periods of growth evaluation (20, 40, 60 and 80 days after transplanting - DAT), giving a total of 12 treatments, with four replications, one for each plant. The Flordaguard and Capdeboscq cultivars showed greater height and stem diameter as well as a greater accumulation of total dry matter at 80 DAT, and both followed the distribution: leaves (67%) > roots (33%), while total dry-matter production in 'Okinawa Roxo' was less, following the order: leaves (71%) > roots (29%). The rootstock under evaluation showed variations in growth, confirmed by the physiological indices, except for the leaf area and specific leaf area. In general, macronutrient accumulation in the shoots and roots of the cultivars during each growth period was different, suggesting intrinsic differences in each of the genetic materials regarding nutrient demand for maintaining the metabolic processes which are vital to plant growth.

Organic cultivation of yellow passion fruit using tall seedlings with long root systems

2019-12-31T21:41:29+00:00

Studies related to adaptation to the environment and different conditions of water availability contribute to decision-making regarding the management of any crop to be implanted. Accordingly, this work aimed to evaluate the yield and quality of organic yellow passion fruit cultivated in a long root system in dryland conditions. The experimental design was in randomized blocks, with five treatments and four replications with four plants each. The treatments consisted of the alteration of the length of the root system, namely: T1 = 25 cm; T2 = 50 cm; T3 = 75 cm; T4 = 100 cm; and T5 = 125 cm. At 120 days after emergence (DAE), the seedlings were transplanted to the field and the following variables were evaluated: plant height (cm) and base diameter (mm) at 120 DAE; total titratable acidity (TTA), total soluble solids (TSS), Ratio (TSS/TTA); and fruit yield. The cultivation of tall seedlings with a long root system provides the maintenance of production during the dry season. The TTA, TSS, and the ratio do not change when modifying the length of the root system, although they do change with the harvest season. The cultivation of passion fruit in an organic system using plants with a long root system with an estimated length of 114 cm provides a higher fruit yield (7,472 kg ha-1) in 22 months of cultivation.

Induction of tolerance to salt stress in soursop seedlings using hydrogen peroxide

2019-12-31T21:00:26+00:00

The exogenous use of hydrogen peroxide is an alternative in the acclimatization of plants to salt stress due to the greater activity of antioxidant enzymes. In this perspective, this study aimed to evaluate the gas exchange and the growth of soursop seedlings under salt stress using hydrogen peroxide. The study was conducted under greenhouse conditions. The treatments were distributed in randomized blocks, in a 5 x 2 factorial arrangement, related to five levels of electrical conductivity of the irrigation water - ECw (0.6, 1.2, 1.8, 2.4, and 3.0 dS m-1) and two concentrations of hydrogen peroxide - H2O2 (0 and 20 μM), with four replicates and two plants per plot. The effects of the treatments were evaluated by the variables of gas exchange and growth. The increase in water salinity negatively affected the gas exchange and the growth of the soursop seedlings. The gas exchange and growth variables presented deleterious effects caused by the salinity of the irrigation water, mitigated by the exogenous application of hydrogen peroxide at the concentration of 20 μM. The exogenous use of hydrogen peroxide at the concentration of 20 μM can be used to induce salt tolerance in soursop seedlings.

Determination of the soil water repellency of the Mediterranean climate by the use of the mini disk infiltrometer. Case of the micro basin of Tifiles, Tenes, Algeria.

2019-12-31T20:45:30+00:00

The soil repellency is one of some soil propriety that can be use to indicate the quality of the soil and give a number of information for the soil conservation and the water management. This study show an example of the determination of this parameter in three sites (forest site, after fire forest site and mixed site) by the use of the mini disk infiltrometer test (MDIT) in the small watershed of wadi Tifiles situated in the North West of Algeria that is characterized by a Mediterranean climate. The result show that the water repellency affect namely the after fire forest site which can be equal to 100% of the measured sample flowed by the mixed soil by 93% and the forest site by 80%.

Fertilization with monoammonium phosphate in the production of Formosa ‘Tainung-01’ papaya in the potiguar semiarid

2019-12-31T20:39:56+00:00

The achievement of good productivity and quality of fruits is directly associated with a balanced fertilization, in which phosphate fertilizers have an important role in the agricultural production system. In this context, this work aimed to evaluate the effect of doses of monoammonium phosphate in ground fertilization and associated with the topdressing in the production of the Formosa “Tainung-01” papaya. The experimental design was in complete randomized blocks, in an split plots outline, having as main factor four fertilizer doses in ground fertilization (0; 80; 160, and 250 kg ha-1 of monoammonium phosphate [MAP]) and, as a sub-portion, two fertilizers in topdressing (20 kg ha-1 of Cosmofert® + 45 kg ha-1 of MAP” and “90 kg ha-1 of MAP). The harvesting began in the eighth month and extended until the 12th month after transplanting of the seedlings. All fruits of five plants per experimental unit were collected and classified. The number of fruits, the production per plant, the yield, and the percentage of marketable fruits were evaluated. The ground fertilization with the monoammonium phosphate did not influence the production of Formosa 'Tainung-01' papaya fruits exclusively destined to the domestic market. When the production is destined to the external market, a dosage of 74.0 kg ha-1 of monoammonium phosphate can be used in ground fertilization.

Morphological and molecular characterization of powdery mildew on watermelon plants in São Paulo state

2019-12-31T20:41:53+00:00

Powdery mildew is one of the most commom foliar diseases of cultivated and wild cucurbits worldwide. Six different fungal species have been reported to be associated with powdery mildew of cucurbits, such as Podosphaera xanthii and Golovinomyces cichoracearum. The aim of the study was to identify the causal agent of the disease in watermelon plants (Citrullus lanatus) cultivated in greenhouses of the State of São Paulo. DNA total was extracted using Chelex method and the ITS region was amplified via standard PCR reaction using the specific primers PMITS1 and PMITS2. A fragment of 700pb was amplified and the sequence showed 99% of identity with P. xanthii (accession number JQ728480). Morphological observation showed that the conidia were ellipsoidal-ovoid, had fibrosin bodies and a bifurcated germinative tube in the lateral position. These characteristics and the molecular analyses confirmed P. xanthi as the etiological agent of powdery mildew in watermelon plants in São Paulo State.

Morphological and molecular characterization of powdery mildew on watermelon plants in São Paulo state