ABSTRACT Vegetable intercropping systems use complementarity between species to increase agricultural profitability. This study evaluated the effects of intercropping chicory and arugula species with collard greens on crop yield and land use efficiency (LUE). Six treatments, consisting of species planted as monocultures or intercropped in various combinations, were evaluated in a randomized block design with four replicates. The cultivars ‘Top Bunch’ (collard greens), ‘Pão de Açúcar’ (chicory) and ‘Folha Larga’ (arugula) were used. The yield of collard greens in monoculture did not differ from those obtained when they were intercropped with chicory, arugula, or both species, whereas chicory and arugula yields were higher in monoculture. However, even with yield losses for chicory and arugula in intercropping, LUE indices were greater than 1.0 in all intercropping systems, indicating their viability. The highest LUE index (2.41) was obtained in the chicory-arugula-collard green intercropping system.

ABSTRACT To evaluate seed vigor, electrical conductivity and ethanol tests are fast and efficient methodologies. They have the potential to be used in several species, such as red rice. However, there are no protocols or information about their efficiency. Thus, the objective was to evaluate the efficiency, and define parameters of execution for electrical conductivity and ethanol tests, to evaluate the vigor of red rice seeds. The study was conducted using four lots of ‘BRS 901’ red rice, which was subjected to a germination test, as well as first count, accelerated aging, and field seedling emergence tests. The electrical conductivity test was performed with 25, 50, and 100 seeds soaked in 50 mL and 75 mL of water, at 25 °C and 30 °C, for 3, 6, 20, and 24 hours, respectively. The ethanol test was performed with 50 and 100 seeds soaked in a volume of water equivalent to 1.0, 1.5, 2.0, 2.5, and 3.0× the mass of the seed sample. To assess the vigor of red rice seeds, the electrical conductivity test is an efficient method when conducted with 50 seeds soaked in 50 mL of water at 25 °C for 20 hours. Meanwhile, the ethanol test is most effective when performed with 50 seeds, in a volume of water that is 2.5× the mass of the sample, at 40 °C for 24 hours.

ABSTRACT The use of green manure from spontaneous species has gained prominence for vegetable crops focused on environmental sustainability and is an alternative method for the Semiarid region in the Northeast of Brazil. Two experiments were conducted in two growing seasons (autumn and spring-summer), in Serra Talhada, PE, Brazil, to evaluate the effects of different amounts of biomass of Calotropis procera (roostertree) and incorporation times on the agro-economic performance of beet crops. A randomized block experimental design was used, with three replications, in a 4 × 4 factorial arrangement; the first factor consisted of amounts of C. procera biomass (5.4, 8.8, 12.2, and 15.6 Mg ha-1 on a dry basis) and the second factor consisted of times of incorporation into the soil (0, 10, 20, and 30 days before planting beet). Commercial root yield, production costs, and the following economic indicators were determined: gross income, net income, return rate, and profitability index. The use of 15.6 Mg ha-1 of C. procera biomass resulted in the highest gross and net incomes and the use of 5.4 and 12.2 Mg ha-1 resulted in the best return rates and profitability indexes in autumn and spring-summer seasons, respectively; the planting time was considered as ideal for the biomass incorporation. The spring-summer growing season resulted in a higher economic return than the autumn growing season. The use of C. procera as a green manure for beet production is economically viable, regardless of the factors evaluated.

ABSTRACT Fig (Ficus carica L.) is widely accepted due to its organoleptic and pharmacological properties. Search for innovations to improve the crop management has increased to reduce environmental impacts and improve the organoleptic quality and food safety of the fruits. Thus, this study aimed to evaluate the influence of fertilization methods and plant training systems on the production and physicochemical traits of fig. The experiment was carried out in a randomized complete block design in a 5 × 4 factorial scheme, with three blocks and three plants per plot. The factors corresponded to five fertilizers (chemical, cattle manure, sheep manure, poultry litter, and organic compost) and four training systems (two branches, three branches, four branches, and espalier). Results showed that, when using chemical fertilizer and poultry litter, plants showed similar productivity and number of fruits, which had similar firmness, length, and peel color (L and °h). The highest production and number of immature fruits were obtained using cattle manure. Soluble solids content and soluble solids content/ titratable acidity ratio were higher in fruits from plants fertilized with cattle manure, sheep manure, and organic compost. On the other hand, plants trained with three and four branches or in espalier produced fruits with the highest soluble solids content and weight. Also, heavier fruits were obtained using chemical fertilization and conducting plants with two, three, and four branches.

ABSTRACT This study aimed to determine how crop residue placement and composition would affect soil water content and temperature during the dry season in the central region of Espírito Santo state, Brazil. A 19-week field study was conducted from April to August 2017. A 2 x 4 factorial study with four replications was implemented using a randomized complete block design. Factors were soil management [conventional tillage (CT) and no soil disturbance (ND)] and residue amendment [maize (Zea mays L.), sunn hemp (Crotalaria juncea L.), a maize-sunn hemp mixture, and a no amendment control]. Soil water content and temperature were measured weekly at predetermined soil depth intervals. Soil water content was higher in ND plots amended with surface residues than under all other treatments in the 0 to 0.05 m depth range. All residue amendments in this range were equally effective in conserving soil water. Surface residues reduced soil temperature by up to 8.4 °C relative to the control in ND plots. Incorporating residue amendments by CT cancelled all temperature-moderating benefits provided by surface residues. These results indicate that surface residues from cereals, legumes, or cereal/legume mixtures are equally effective in conserving soil water and moderating soil temperature during the dry season. Additional research is needed to determine how improved soil environmental conditions, generated by surface residues, would affect nutrient acquisition and crop performance.

ABSTRACT Corn, one of the main grain crops in Brazil, needs to have its nutritional requirements fully satisfied to achieve high biological productivity. Thus, the objective of this work was to evaluate the influence of increasing doses of poultry litter biochar on nutrient concentrations in the leaves of hybrid corn BRS 2022 and in the soil after harvest. The experiment was carried out in a completely randomized design, with four replicates, evaluating six doses of biochar (0; 2.02; 4.05; 6.07; 8.10 and 10.12 t ha-1) and the plots composed of one plant per pot with a volume of 20 dm3. The collection of leaves for leaf diagnosis was carried out at the time of flowering, removing the opposite leaf from the ear base in the middle third region. These leaves were dried in a forced air circulation oven, 65 °C, for a period of 48 hours, ground, sieved through 20 mesh and analyzed for the concentrations of macronutrients in the leaf tissue. At the end of the experiment, 83 days after corn sowing, soil samples were collected as a function of the treatments and then analyzed chemically. Biochar application promoted an increase in the leaf contents of N, P and K, resulting in improvements in the nutritional status of plants for these nutrients. The chemical characteristics of the soil, analyzed after the corn harvest, revealed that there was an influence of the doses of biochar on the levels of calcium, organic carbon, potassium and phosphorus.

ABSTRACT The objective of this work was to characterize the physical and physicochemical parameters of pequi powders obtained by means of convective drying at different temperatures (50, 60, 70 and 80 °C) and pulp layer thicknesses (0.5, 1.0 and 1.5 cm). Initially, the physicochemical characterization of fresh pulp was carried out, followed by convective drying under the conditions mentioned, until the equilibrium moisture content and subsequent disintegration to obtain the powders. Subsequently, the physical and physicochemical properties of the obtained powders were analyzed and the best powder was selected based on reduced moisture content and water activity and lower peroxide index. Pequi pulp showed a high fat content and a yellowish color; with the increase in drying temperature, there were reductions in the moisture content, water activity and protein content of the powders. As for the color parameters, the powder showed a darkening with the increase in drying time; the water adsorption isotherms of the selected pequi powder were classified as Type II, and the GAB model showed the best fits. The pequi powders showed good solubility and low cohesiveness. The powder that showed good flowability was produced at a drying temperature of 60 °C and with pequi pulp layer thickness of 0.5 cm.

ABSTRACT The quality parameters of cassava roots vary between cultivars and depend on abiotic factors, such as plant nutrition. However, the magnitude of how these factors interfere is not yet well defined, especially for phosphorus (P), which is a nutrient directly linked to the synthesis of sugars and starches in plants. Thus, the objective of the research was to evaluate the quality of roots of table cassava cultivars fertilized with doses of P in the Brazilian semiarid. The research was carried out at the Rafael Fernandes experimental farm, Mossoró, RN, Brazil, from June 2018 to April 2019. The experimental design used was in randomized blocks, arranged in subdivided plots and with four replications. Doses of P (0, 60, 120, 180 and 240 kg ha-1 of P2O5) were applied in the plots, and in the subplots, the table cassava cultivars (Água Morna, BRS Gema de Ovo, Recife and Venâncio). Firmness, elasticity, titratable acidity, soluble solids, total soluble sugars, starch and cooking were all evaluated. The quality of table cassava roots varied depending on the cultivar and the dose of P. Doses of P between 120 and 240 kg ha-1 of P2O5 increase the starch content and reduce the cooking time of table cassava roots.

ABSTRACT Bitter melon (Momordica charantia L.) is a plant species recommended by the Brazilian Health Regulatory Agency (Anvisa) as hypoglycemiant. The characterization of plants is an essential step in any breeding program. The objective of the present work was to organize and characterize a bitter melon germplasm collection, based on morpho-agronomic characters, to assess its genetic diversity and identify genotypes of agronomic interest. Eighty-eight genotypes were characterized for 38 descriptors. Redundant descriptors were identified through Principal Component Analysis (PCA); after their exclusions, a new PCA was carried out to verify the dispersion among the genotypes. Groups in the PCA were defined using the kmeans clustering method. The groups were studied for phenotype pattern using radar chart. Populational diversity was estimated through Shannon and Pielou indexes. Intra group diversity was estimated through analysis of similarity (anosim). The relative importance of variables for diversity was also estimated. Seventeen variables were redundant. The genotypes were grouped into 5 groups. Groups G1 and G5 were antagonist regarding fruit and seed productions and fruit, leaf, and seed sizes. A trend of decrease in fruit, leaf, and seed sizes was found in groups from G1 to G5. The diversity was high. Intra group diversity was high among small fruit genotypes, and low for medium-sized fruit genotypes. The variable number of male flowers (NMFL) was identified as that presented the greatest contribution to estimation of diversity. The genotypes UFRRJ MSC072, 042, 028, and 087 stood out with the highest number of fruits produced.

ABSTRACT - Based on its nutritional and economic value, the lima bean (Phaseolus lunatus L.) is the second most important species of the genus. It has high genetic diversity and potential for production and is considered an alternative food and income source. The objective of this study was to apply the restricted maximum likelihood/ best linear unbiased prediction (REML/ BLUP) methodology to estimate genetic parameters and predict genotypic values in F3 populations of lima beans. Twelve characteristics were evaluated in five populations with indeterminate growth habits (H39, H72, H53, H90, and H56). Model 83 from the Selegen program was used for analysis. Considering the genetic parameters, the highest values of genetic variance were for plant height and number of pods per plant. Pod thickness and seed width are favorable for breeding programs. Seed width selection gain was significant for populations H56 and H90 at 11.26 mm and 10.50 mm, respectively. As for the length and thickness of seeds, the gains were less significant, with population H53 showing the greatest gain. The REML/ BLUP methodology proved efficient in estimating genetic parameters and predicting gains in lima bean populations. The estimated selection gains indicated that the highest gains were obtained for plant height, the number of pods per plant, pod thickness, seed width, and the number of days to maturity. Populations H53 and H56 stood out for having large and white seeds, thus being potential populations for species improvement.