Search

Selecting genotypes tolerant to high temperatures is an important measure for agricultural maintenance and production in climate change scenarios. Thus, this study aimed to select cowpea genotypes tolerant to increased air temperature. A total of 20 cowpea genotypes were used, cultivated under temperature regimes of 20–26–33 °C and 24.8–30.8–37.8 °C in a completely randomized experimental design under a 2 × 20 factorial scheme (temperature regimes × genotypes). The BRS Inhuma, Bico-de-Ouro-17-45, BRS Guariba, and BRS Imponente genotypes did not show significant differences in the analyzed physiological responses to the increase in air temperature. The BRS Inhuma, Bico-de-Oouro-17-19, Bico-de-Ouro-17-44, Bico-de-Ouro-17-45, BRS Guariba, and BRS Imponente genotypes showed increased temperature tolerance as thermal stress did not affect production. The Pingo-de-Ouro-17-48, MNC00-595F-27, MNC06-895E-1, and MNC09-981B-2 genotypes reduced water efficiency by −26.85, −25.19, −40.04, and −60.37%, respectively, due to the increase in temperature. The results obtained in this work represent a pre-selection of genotypes that are tolerant to high temperatures, with the BRS Inhuma, Bico-de-Ouro-17-45, BRS Guariba, and BRS Imponente genotypes indicated as tolerant to increased temperatures based on the interaction of physiological and productive responses. There is an urgent need to select cowpea genotypes tolerant to increased temperature to maintain production in climate change scenarios and ensure agricultural systems’ sustainability and food security.

Zinc (Zn) is crucial for both plant metabolism and human nutrition, with its deficiency being a global health concern. Strategies to increase its availability in food, such as agronomic biofortification, have gained prominence. This study evaluated the impact of foliar spraying of Zn [at full bloom stage: 0 (control) and 600 g ha−1, as ZnSO4⋅7H2O] on the nutritional quality of cowpea (Vigna unguiculata L. Walp.) grains. Field experiments involving 20 cowpea genotypes were carried out over two seasons in a Typic Quartzipsamment under a no-tillage system. The photosynthetic responses of cowpea plants and the concentrations of Zn, amino acids, sucrose, total sugars, and storage proteins (glutelin, albumin, prolamin, and globulin) in grains were analyzed. All genotypes showed enrichment of Zn in grains in response to ZnSO4⋅7H2O application compared to untreated plants. Foliar spraying of ZnSO4⋅7H2O during initial grain filling was ideal for increasing Zn concentration in grains and improving plant physiological processes. Additionally, Zn fertilization led to higher concentrations of storage and total amino acids and proteins in the grains, supporting the rational application of Zn in cowpea production to improve the nutritional quality of grains and increase plant productivity.

Abstract The objective of this work was to select superior cowpea lines derived from local cultivars for the semiarid region of southeastern Piauí, Brazil. A total of 38 genotypes (36 lines and two commercial cultivars) were evaluated in a randomized complete block design, with two replicates, in the municipality of Ipiranga do Piauí, in the state of Piauí. The following traits were evaluated: number of days to the onset of flowering, pod length, number of grains per pod, weight of 100 grains, commercial grain quality, and grain yield. Deviance analyzes were performed using the restricted maximum likelihood and best unbiased predictor approach, the parameters and genetic values were estimated, and simultaneous selection was carried out via the sum of ranks index. The likelihood ratio test showed a significant difference between the evaluated genotypes. Lines 36, 5, 24, 8, 2, 23, 29, 28, 34, 6, 19, 11, 7, and 20 are superior for the set of evaluated traits and, therefore, are the most promising to compose the advanced trial of the cowpea breeding program and to generate cultivars for family farmers in the semiarid region of southeastern Piauí.

Abstract This study aims to compare the grain protein profile of four Brazilian cowpea cultivars (BRS Aracê, BRS Itaim, BRS Pajeú, and BRS Xiquexique) by two-dimensional electrophoresis (2-DE) and principal component analysis (PCA). 2-DE efficiently separate cowpea protein profiles, showing high homogeneity among the four cultivars. In addition, the principal component analysis indicated that there is a difference in abundance of proteins among the cultivars. The cultivars BRS Aracê and BRS Xiquexique, both biofortified in iron and zinc, were separated from the cultivars BRS Itaim and BRS Pajeú. These results demonstrate that protein profiles can be used to discriminate cowpea varieties. Graphical Abstract

Abstract Cowpea is grown mainly in regions with a hot semi-arid climate, where other pulses do not develop satisfactorily. It is the 4th most produced pulse in the world, thus supplying the domestic and export markets. Following the trends of the food products market, a study was carried out to identify the best condition of the extrusion process, to transform these nutritious grains into quality expanded products and ready for consumption. The grains were decorticated and transformed into cotyledon flour. This flour was conditioned and the Evolum HT25 twin screw extruder feeder was adjusted to a rate of 7 kg h-1. A Box-Behnken 23 design was used, considering the following variables and levels: extrusion temperature from 100 °C to 140 °C (in the 7th to 10th zone), screw speed (300 to 700 rpm) and conditioning moisture from 12% to 16%. The temperature affected linearly and negatively (p ≤ 0.05) the sectional expansion index (2.65 to 7.64). The screw speed interfered linearly and positively (p ≤ 0.05) in the longitudinal (1.12 to 9.32) and volumetric (4.91 to 24.15) expansion index, and negatively with the water absorption index (3.05 to 3.86 g g-1). The screw speed (positive linear and negative quadratic), the moisture content (negative quadratic) and the interaction (positive) between the two interfered (p ≤ 0.05) in the water solubility index (25.89% to 33.85%). The hardness value (1.24 to 2.83 N) was affected (p ≤ 0.05) by screw speed (negative linear and positive quadratic), temperature (negative quadratic), moisture (positive quadratic), and interactions of moisture with temperature and screw speed. To obtain a hardness value close to that of commercial extrudates and high-water solubility, the maximum global desirability obtained was 0.81 for extrusion at 135.6 °C, 700 rpm and 12% moisture.

Abstract Plant breeding reduces the genetic diversity of plants and could influence the composition, structure, and diversity of the rhizosphere microbiome, selecting more homogeneous and specialized microbes. In this study, we used 16S rRNA sequencing to assess the bacterial community in the rhizosphere of different lines and modern cowpea cultivars, to investigate the effect of cowpea breeding on bacterial community assembly. Thus, two African lines (IT85F-2687 and IT82D-60) and two Brazilian cultivars (BRS-Guariba and BRS-Tumucumaque) of cowpea were assessed to verify if the generation advance and genetic breeding influence the bacterial community in the rhizosphere. No significant differences were found in the structure, richness, and diversity of bacterial community structure between the rhizosphere of the different cowpea genotypes, and only slight differences were found at the OTU level. The complexity of the co-occurrence network decreased from African lines to Brazilian cultivars. Regarding functional prediction, the core functions were significantly altered according to the genotypes. In general, African lines presented a more abundance of groups related to chemoheterotrophy, while the rhizosphere of the modern cultivars decreased functions related to cellulolysis. This study showed that the genetic breeding process affects the dynamics of the rhizosphere community, decreasing the complexity of interaction in one cultivar. As these cowpea genotypes are genetically related, it could suggest a new hypothesis of how genetic breeding of similar genotypes could influence the rhizosphere microbiome.

Cowpea is a widely cultivated crop in the world. Biofortification strategies aim to reduce mineral and protein deficiencies, especially among the poorest people. The aim of this study was to estimate adaptability and stability of cowpea genotypes for iron, zinc and protein contents, through GGE biplot analysis. Twenty cowpea genotypes were evaluated in the municipalities of Piauí Monsenhor Hipólito, Pio IX and São Miguel do Tapuio, under rainfed conditions. The experimental design was a randomized block design with four replications. The traits evaluated were grain yield, iron, zinc and protein contents in dry grains. Iron (Fe) and zinc (Zn) were determined by flame atomic absorption spectrophotometer, and protein contents by Kjeldahl methods. Adaptability and stability were evaluated by GGE biplot analyses. The means of the experiments were 1,209.1 kg ha−1, 51.1 mg kg−1, 46.8 mg kg−1 and 24.3% for grain yield, Fe, Zn and protein contents, respectively. The joint analysis of variance showed significant difference (p < 0.05) for the effect of interaction genotypes by environments for Fe, Zn and protein contents. The lines G6 and G8 were the most promising for grain yield, mineral and protein content through adaptability and stability by GGE biplot approach.

Abstract The objective of this work was to select cowpea lines with compound inflorescences that show a high potential to generate the first commercial cultivar with this characteristic in Brazil. Thirty-seven lines were evaluated in a randomized complete block design, with two replicates, in 2021, in the municipality of Teresina, in the state of Piauí. The following traits were evaluated: number of days to the onset of flowering, plant size, commercial grain quality, number of grains per pod, weight of 100 grains, and grain yield. Deviance analyzes were performed by the restricted maximum likelihood/ best unbiased linear predictor methodology, and the values and genetic parameters necessary to carry out simultaneous selection were estimated based on the rank sum index. A statistical difference was detected between the lines evaluated by the likelihood ratio test (LRT). In general, genetic variance was the largest component of phenotypic variance for the evaluated traits. The ten most promising cowpea lines with compound inflorescences are: MNC15-33E-123, MNC15-33E-178, MNC15-33E-222, MNC15-33E-171, MNC15-33E-232, MNC15-33E-223, MNC15-33E-219, MNC15-33E-183, MNC15-33E-91, and MNC15-33E-165. These lines were selected for the next selection stages and show a high potential to generate the first commercial cowpea cultivar with compound inflorescences in Brazil.

ABSTRACT - Cowpea is a very important food for the populations of the North and Northeast regions of Brazil, representing an excellent source of proteins and minerals. The purpose of this study was to evaluate the potential of 100 cowpea genotypes for biofortification of iron, zinc, and proteins, and cooking quality of the grain. The iron and zinc contents were analyzed by x-ray fluorescence spectrometry; protein content was based on nitrogen determination, using the Kjeldahl method; and cooking quality was assessed using an electric pressure cooker and Mattson cooker. The superiority of genotypes for iron, zinc, proteins, and cooking quality was carried out using the nutritional quality and cooking index. The iron content ranged from 3.58 to 6.06 mg 100g-1, with an overall average of 4.66 mg 100g-1, while the zinc content between 2.35 and 4.57 mg 100g-1 and average of 3.31 mg 100g-1. Protein range ranged from 20.82 to 26.92 g 100g-1 and an average of 24.30 g 100g-1. The percentage of cooked grains ranged from 20 to 98%, with an average of 68.7%. The line MNC11-1023E-28 has the best profile of nutritional and cooking quality, showing potential as a food to meet consumer demands and reverse iron and zinc deficiency in the Brazilian population.

ABSTRACT Cowpea is a great socioeconomically important leguminous plant worldwide. The crop is an excellent source of proteins and minerals, mainly for the poorest populations. It is cultivated in some states of Brazil. The Piauí semi-arid is the most yielding zone in the state. Thus, the selection of superior cowpea genotypes for multi-traits and adaptabilities to this growing area is very important for the small-scale and medium-scale farmers in Piauí. The objective of this study was to select the superior cowpea lines for their multi-traits and adaptabilities to the Piauí semi-arid zone based on the genotype by the yield*trait (GYT) Biplot approach. Seventeen elite lines and three cultivars were evaluated in a randomized complete block design with four replications under the rainfed growing condition at three different locations away from the Piauí semi-arid zone. The following traits were evaluated: the number of days to flowering, pod length, the number of grains per pod, weight of one hundred grains, grain index, grain yield, Fe and Zn contents, and also the cooking quality. The analysis of variance (ANOVA), the grouping of means, and simultaneous selection by the GYT Biplot were implemented. Through the GYT Biplot approach, the two lines, MNC11-1013E-35 and MNC11-1013E-15, were found superior because they combined the traits, grain-yield with the yield components and nutritional traits simultaneously during the cultivation in the Piauí semi-arid zone. However, the MNC11-1052E-3 line was better in the combination of yield and cooking quality than the other lines.

ABSTRACT: The potential expression of crop productivity is a constant challenge for plant breeders in the face of oscillations in environmental variables, making selection difficult and increasing the operational and methodological costs in obtaining the ideal cultivar for a determined region. The objective of the research was to investigate the effects of genotype x environment interaction in the selection of cowpea lines with high grain yield, adaptability, and genotypic stability simultaneously, in environments of the Northwest region of Rio de Janeiro State, using mixed models (Maximum Restricted Likelihood - REML/Best Linear Unbiased Prediction - BLUP). 27 cowpea genotypes were evaluated in six environments by combining location (Cambuci-RJ and Bom Jesus do Itabapoana-RJ) and year (2016, 2017 and 2018). A randomized block design with four replications was performed. The genetic parameters were estimated via the REML/BLUP procedure, and the selection was based on the harmonic mean method of the relative performance of the genetic values (HMRPGV). A meaningful difference was observed for environment and genotype x environment interaction. The residual variance and the variance of the genotype x environment interaction formed the most significant fractions of the phenotypic variance. Lines 4 (Bico-de-ouro 1-5-24), 6 (Pingo-de-Ouro 1-5-4), 5 (Pingo-de-Ouro 1-5-26), and 9 (Pingo-de-Ouro 1-5-8), stood out as superior in terms of stability and adaptability and grain yield by HMRPGV. Commercial cultivars 13 (BRS-Tumucumaque) and 26 (BRS-Itaim) had high grain yield, adaptability, and specific stability in the evaluated edaphoclimatic conditions.

ABSTRACT The present work aimed to evaluate the contents of total phenolic compounds, total flavonoids and antioxidant activity, as well as to identify and quantify phenolic acids before and after simulated gastrointestinal digestion in vitro, in raw and cooked cowpea grains, of biofortified cultivars BRS Aracê and BRS Tumucumaque. The raw grains were analyzed as flour and the cooked grains were analyzed after maceration, before and after cooking and in the stages of the digestive process. The contents of total phenolic compounds were analyzed by the spectrophotometric method, using the reagent Folin-Ciocalteu, and total flavonoids using a spectrophotometric method with quercetin as standard. The antioxidant activity was evaluated using the free radical capture method ABTS (2,2'-azino-bis (3-ethylbenzothiazolino-6-sulfonic acid) and FRAP (Ferric Reducing Antioxidant Power). Eight phenolic acids were investigated, and the identification and quantification was performed by high performance liquid chromatography (HPLC), the content of total phenolic compounds and the antioxidant activity were reduced during cooking, but increased with simulated digestion in vitro, due to the release of bound forms. action of digestive enzymes, there was a difference in the behavior of the raw and cooked cultivars.The phenolic acids suffered degradation under gastrointestinal conditions, but the cultivars analyzed maintained compounds with relevant bioactivity (raw grain - gallic, caffeic and p-cumáric acids; cooked grain - acids and caffeine) and antioxidant activity, which can help protect against chronic non-communicable diseases, demonstrating that cowpea is a common food bioaccessible natural antioxidants.

Background: Biofortification is a method that improves the nutritional value of food crops through conventional plant breeding. The aim of this study was to evaluate the effects of intra-amniotic administration of soluble extracts from zinc (Zn) biofortified and Zn standard cowpea (Vigna unguiculata L. Walp.) flour on intestinal functionality and morphology, inflammation, and gut microbiota, in vivo. Methods: Seven treatment groups were utilized: (1) No Injection; (2) 18 MΩ H2O; (3) 50 mg/mL Inulin; (4) 50 mg/mL BRS Pajeú soluble extract (Zn standard); (5) 50 mg/mL BRS Aracê soluble extract (Zn biofortified); (6) 50 mg/mL BRS Imponente soluble extract (Zn biofortified); (7) 50 mg/mL BRS Xiquexique soluble extract (Zn biofortified). Results: Treatment groups with BRS Imponente and BRS Xiquexique reduced the abundance of Clostridium and E. coli when compared with all other experimental groups. All cowpea soluble extracts increased villi goblet cell number (total), specifically acidic goblet cell type number per villi relative to inulin and 18MΩ H2O groups. Moreover, BRS Xiquexique increased the crypt goblet diameter and the crypt depth compared to all treatments and controls. The Zn content in the Zn biofortified cowpea flours was higher when compared to the Zn standard flour (BRS Pajeú), and the phytate: Zn molar ratio was lower in the Zn biofortified flours compared to the Zn standard flour. In general, all cowpea soluble extracts maintained the gene expression of proteins involved with Zn and iron absorption, brush border membrane (BBM) functionality and inflammation compared to inulin and 18MΩ H2O. Conclusions: This study demonstrates the potential nutritional benefit of standard and biofortified cowpea treatment groups to improve intestinal morphology, BBM functionality, inflammation, and gut microbiota, with the highest effect of BRS Xiquexique soluble extracts to improve assessed cecal microflora populations and intestinal morphology.

The objective of this work was to evaluate the agronomic performance of erect and semi-erect cowpea elite lines grown in the States of Minas Gerais and Mato Grosso, Brazil. The experiments were conducted in Jaíba, Janaúba, Sete Lagoas (Minas Gerais), Primavera do Leste and Nova Ubiratã (Mato Grosso), with 20 genotypes of cowpea, arranged in a randomized block design with four replications. The data were subjected to individual and joint analyses of variance and means grouped by the Scott-Knott test (p

The low use of technologies by farmers and the occurrence of biotic and abiotic stresses are limiting factors for cowpea production in the Brazilian Northeast region. The tolerance of genotypes to drought is an alternative to decrease the negative effects of stresses on cowpea production. Thus, the objective of this work was to identify parents and combinations of cowpea genotypes with high probability of generating segregating populations with tolerance to drought. Six cowpea genotypes were crossed in a complete diallel cross design, totaling 30 F2 populations, which were evaluated together with their parents in an experiment under water deficit at the experimental field of the Embrapa Mid-North, Teresina, State of Piauí, Brazil. A triple lattice incomplete block experiment design was used, with three replications, with experimental plot consisting of six 2-m plant rows. Fifteen plants per plot were sampled to evaluate their agronomic characteristics, whose results were subjected to analysis of variance and means were used to estimate the general and specific combining abilities. The genotypes showed significant differences in all characteristics evaluated, denoting the genetic variability of the population. The additive effects were more important than the non-additive effects, and maternal inheritance was detected. The genotypes BRS Xiquexique, Pingo-de-Ouro-1-2 and MNC99-510F-16-1 were the most promising for use in recurrent selection programs for tolerance to water deficit. The hybrid combinations (1) BRS Paraguaçu X (4) CNCx-698-128G, (2) Pingo-de-Ouro-1-2 X (3) BRS Xiquexique, (3) BRS Xiquexique X (5) Santo-Inácio, (4) CNCx-698-128G X (6) MNC99-510F-16-1 and (5) Santo-Inácio X (4) CNCx-698-128G showed potential for generating superior lineages regarding bean production and tolerance to water deficit.

Cowpea is one of the major food crops in Northeast Brazil, where it is commonly cultivated in the semi-arid regions with limited water availability. It is important to study the elicitors associated with cowpea to mitigate any deleterious effects of abiotic stress on the initial establishment of this crop. In this study, we aimed to evaluate the morphophysiological changes in cowpea cultivars under osmotic stress with seeds soaked in salicylic acid. The germination test was conducted in B.O.D germination chambers. The seeds of three cowpea cultivars: BRS Tumucumaque, BRS Aracê, and BRS Guariba, were germinated at five osmotic potentials (0.0; -0.2; -0.4; -0.6, and -0.8 MPa) after three pre-treatments: pre-soaking in deionized water, pre-soaking in salicylic acid, and without pre-soaking. The following parameters were evaluated: germination, germination speed index, seedling height, total phytomass, contents of chlorophyll ‘a’ and ‘b’, carotenoid content, electrolyte leakage, water content, and proline content. Our results indicate that salicylic acid promotes reduction in the harmful effects of abiotic stress, which is reflected in the increase in germination percentage, seedling height, and chlorophyll and carotenoid content as well as in the adjustment of electrolyte leakage and increase in proline content under induced water stress conditions. The cultivar BRS Guariba proved to be more tolerant to water deficit during germination and initial growth stages, when the seeds were treated with salicylic acid (1 mM).

Cowpea bean is a socioeconomically important legume that contribute to generate employment and income. This species presents great grain variability, and the commercial subclass black eye stands out as a very appreciated grain in Brazil and abroad, thus requiring the development of new cultivars. The objective of this work was to evaluate and select lineages of commercial black eye cowpea, based on simultaneous, and direct selection. First, 105 progenies and four controls were evaluated using the Federer's augmented block design. Seventy-seven progenies, selected from this evaluation-first selection cycle-and four controls were evaluated in three environments, using a simple 9×9 lattice design. Based on this evaluation, the second selection cycle was possible, resulting in 24 progenies. The gain by direct selection was lower than the predicted gain for grain yield in the first cycle, indicating that the selection was not effective. This result was probably due to the reduced genetic variability caused by the selection pressure. In the second cycle, the predicted and observed gains were similar, indicating that much of the expected gain was observed. The predicted and observed gains, with simultaneous selection based on the rank sum selection index, were similar in the first and second cycle. The simultaneous and direct selections resulted in genetic gains for grain yield in the two selection cycles, making it possible the selection of high grain yield lineages.

Water deficit affects plant development and the overcoming of its effects depends on the genotype, duration of stress, severity of damage and development stage of the plant at water stress. Cowpea is considered tolerant to water deficit, however, studies have shown that its yield can be reduced under this condition. Thus, the objective of this work was to evaluate the effect of water deficit on F2 populations of cowpea and select tolerant genotypes. Thirty F2 populations of cowpea and their parents (BRS-Paraguaçu, Pingo-de-Ouro-1-2, BRS-Xiquexique, CNCx-698-128G, Santo-Inácio and MNC99-510F-16-1) were evaluated in two experiments, one under induced water deficit and other under full irrigation, in the experimental field of the Embrapa Mid-North, in Teresina, State of Piauí, Brazil. A triple lattice incomplete block experiment design was used, with three replications. The experimental plots consisted of six 2-m rows, with spacing of 1.0 m between rows and 0.50 m between plants. The grain production was evaluated and its decrease related to the relative production and tolerance to stress was calculated. The grain production of the genotypes had an average decrease of 29.83% under water deficit. The genotypes from the crosses BRS-Paraguaçu x CNCx-698-128G, BRS-Xiquexique x Pingo-de-Ouro-1-2, CNCx-698-128G x BRS-Xiquexique, CNCx-698-128G x MNC99-510F-16-1, Santo-Inácio x BRS-Xiquexique and MNC99-510F-16-1 x BRS-Paraguaçu had high production and high tolerance to water deficit.

The GGE Biplot method is efficien to identify favorable genotypes and ideal environments for evaluation. Therefore, the objective of this work was to evaluate the genotype by environment interaction (G×E) and select elite lines of cowpea from genotypes, which are part of the cultivation and use value tests of the Embrapa Meio-Norte Breeding Program, for regions of the Brazilian Cerrado, by the GGE-Biplot method. The grain yield of 40 cowpea genotypes, 30 lines and 10 cultivars, was evaluated during three years (2010, 2011 and 2012) in three locations: Balsas (BAL), São Raimundo das Mangabeiras (SRM) and Primavera do Leste (PRL). The data were subjected to analysis of variance, and adjusted means were obtained to perform the GGE-Biplot analysis. The graphic results showed variation in the performance of the genotypes in the locations evaluated over the years. The performance of the lines MNC02-675F-4-9 and MNC02-675F-4-10 were considered ideal, with maximum yield and good stability in the locations evaluated. There mega-environments were formed, encompassing environments correlated positively. The lines MNC02-675F-4-9, MNC02-675F-9-3 and MNC02-701F-2 had the best performance within each mega-environment. The environment PRL10 and lines near this environment, such as MNC02-677F-2, MNC02-677F-5 and the control cultivar (BRS-Marataoã) could be classified as those of greater reliability, determined basically by the genotypic effects, with reduced G×E. Most of the environments evaluated were ideal for evaluation of G×E, since the genotypes were well discriminated on them. Therefore, the selection of genotypes with adaptability and superior performance for specific environments through the GGE-Biplot analysis was possible.

Flour production through milling is an alternative for the cowpea processing, when the aim is to obtain a product with higher added value. The objective of this work was to determine the chemical composition, the granulometry, and evaluate the microbiological characteristics of whole-bean flours from five cowpea cultivars (BRS Cauamé, BRS Guariba, BRS Xiquexique, BRS Novaera and BRS Itaim). Cowpea beans were dried in a oven (Fanem, 320-SE) at 50 °C for 6 hours, milled in a cyclone-type rotor mill (Tecnal, TE-651/2) and, subsequently, in a pulverizer-type semi-industrial mill (Fritsch, Pulverisette 14) to obtain the flour. The flour centesimal composition, total energetic value, mineral content, granulometry, microbiological characteristics, and technological properties-flour water absorption and solubility in water-were analyzed. All analyzes were performed in triplicate and the results expressed in mean ± standard deviation. The means were compared by the Scott-Knott test (p ≤ 0.05). The flour centesimal composition presented (g per 100 g of flour): 7.13 to 10.33 of moisture, 2.06 to 3.65 of ashes, 1.53 g to 2.90 of lipids, 21.73 to 25.77 of proteins, and 58.08 to 64.02 of carbohydrate. The flours had on average 359.04 Kcal (100 g) and presented high iron, zinc, copper, manganese, phosphorus and magnesium contents. The whole-bean flours from the cultivars BRS Cauamé and BRS Xiquexique are sources of calcium. Regarding the microbiological characteristics, all flours are innocuous. The water absorption index were within 1.77 and 2.20 g g-1 and the water solubility index within 17 and 23%. All whole-bean flours had good nutritional, technological and microbiological characteristics, and thus potential for use in bakery products.

The cowpea Vigna unguiculata (L.) Walp., also known as cowpea, is of fundamental socioeconomic importance to the northeast of Brazil, and has become one of the main sources of protein in the diet of the rural population. However, in this region, it has become necessary to identify genotypes that are better adapted to drought. In addition, research is needed regarding the action of substances that promote tolerance to stress factors. The aim of this study was to evaluate the antioxidative response of cowpea cultivars under osmotic stress conditions using potassium nitrate as an attenuator. Five osmotic potentials were tested in the substrate (0.0, −0.2, −0.4, −0.6, and −0.8 MPa), and three seed treatments (pre-soaking in distilled water, pre-soaking in potassium nitrate, and without pre-soaking) were tested in three cowpea cultivars (BRS Itaim, BRS Aracê, and BRS Potengi). The design was randomized with 45 treatments and four replications. The data were submitted to analysis of variance (P < 0.05), and in cases of significance, regression analysis was conducted to quantitate the factors. Our results indicate that an increase in proline content in cowpea plants may be seen as indicative of the intensity of water stress on germination and the initial stages of growth of the plant. The BRS Itaim cultivar best tolerates drought conditions with the application of potassium nitrate, given the increased activity of antioxidant enzymes such as superoxide dismutase, catalase, and ascorbate peroxidase.

This study aimed to determine the effect of cooking on the centesimal compositions, the content of bioactive compounds, and antioxidant activities in beans of the cowpea cultivars. The beans were cooked without soaking (1:5 w/v) in a pressure cooker for 780 seconds. Statistical analysis was performed using Student’s t-test to determine the difference between means of raw and cooked beans. One-way ANOVA: post-hoc Tukey’s test was applied at 5% to compare the data of the cultivars. Significant difference (p 0.05) was noted between the moisture contents of samples, with values ranging from 10.69 to 11.37% in the raw beans and 63.32 to 75.43% in the cooked ones. Only BRS Marataoã showed a slight reduction (1.24%) in the energy value. The total polyphenol content in cooked beans decreased on discarding the broth. BRS Marataoã showed the highest levels of total polyphenols and flavonoids in raw beans, cooked beans, and broth. The raw beans of the cultivar BRS Itaim had greater content of condensed tannins and total anthocyanins. The raw beans, cooked beans, and broth showed statistically significant differences between their antioxidant activities, and the best results were found in the samples not subjected to thermal processing, particularly in BRS Marataoã. In conclusion, cooking influenced the concentration of bioactive compounds and antioxidant activities of the beans. Therefore, it is recommended that cooked cowpea beans should be consumed with the cooking broth for optimization of antioxidants.

ABSTRACT The development and enrichment of food are of great importance not only for the industry but also to improve the population's nutrition, where you can create new products or optimize existing ones. The consumption of fortified products in the diet is an option for the control of deficiency diseases. This study aimed to develop enriched cheese bread with whole biofortified cowpea flour and evaluate their acceptance and chemical composition. Two formulations, F1 and F2, were prepared containing 5.6 and 8% of cowpea flour as a substitute for starch, respectively. To check acceptance, three sensory tests were used (Hedonic Scale, Purchase Intent, and Paired Comparison), F1 being sensory viable according to assessors, being chemically analyzed. Minerals were determined by atomic emission spectrometry with inductively coupled plasma source. The moisture was determined by drying at 105 °C, ash by calcination in muffle at 550 °C, proteins by the macro-Kjeldahl method, and lipids by hot extraction in a Soxhlet extractor. Carbohydrates were obtained by difference and the calories were calculated. The addition of cowpea increased the amounts of copper, iron, phosphorus, magnesium, manganese, and zinc, as well as protein and carbohydrate values. On the other hand, there was a reduction of the moisture concerning lipids and the total caloric value compared to the standard formulation. It was concluded , therefore, that the cowpea, a regional raw material in market expansion is presented as an option for the enrichment of baked foods that do not contain gluten, such as cheese bread.

O objetivo deste trabalho foi avaliar a variabilidade de genótipos de feijão-caupi e selecionar aqueles com potencial para o mercado de vagens e grãos verdes. Em 2012, foram avaliados 16 genótipos em dois experimentos (sequeiro e irrigado), em delineamento de blocos ao acaso, com quatro repetições. Foram avaliados os caracteres: número de dias para o início da floração, comprimento de vagem verde, número de grãos por vagem verde, massa de cem grãos verdes, produtividade de vagens verdes, produtividade de grãos verdes e índice de grãos verdes. A maioria dos caracteres apresentou diferenças quanto ao ambiente de cultivo, mas a resposta dos genótipos às variações ambientais foi similar. Os genótipos, sob irrigação, apresentaram produtividade de vagens e grãos verdes similar à das testemunhas. A cultivar Azulão-MS, em sequeiro, apresentou alto potencial para a produção de vagens verdes, no entanto, com baixa relação grão verde/vagem verde. A cultivar BRS Tumucumaque apresenta potencial para a produtividade de grãos verdes em sequeiro, enquanto a linhagem MNC00-595F-27 produz mais em condições de irrigação.

Devido à variabilidade das leguminosas quanto à eficiência da fixação biológica de nitrogênio (FBN), tem sido enfatizada a importância do melhoramento genético vegetal no favorecimento da fixação do nitrogênio. Este estudo teve como objetivo avaliar a eficiência simbiótica de progenitores de cultivares brasileiras de feijão-caupi e dar suporte científico à inclusão da FBN ao programa de melhoramento genético da cultura do feijão-caupi no Brasil. O experimento foi conduzido em Teresina, Piauí. Utilizou-se delineamento experimental em blocos casualizados em esquema fatorial 6 x 5, com três repetições, sendo seis fontes de N: quatro estirpes de bactérias diazotróficas (BR 3267, BR 3299, BR 3262 e INPA 03-11B), um tratamento com nitrogênio mineral e outro sem inoculação e sem N; e cinco genótipos de feijão-caupi: quatro progenitores (TVu 1190, Pitiúba, CNC 0434 e Alagoano) e uma cultivar (BRS Guariba). Na análise de variância utilizou-se software SAS e as médias foram comparadas pelo teste Tukey. O progenitor Alagoano destacou-se dos demais em eficiência de nodulação, foi superior ao Pitiúba em massa seca de nódulos e diferiu do TVu 1190 em nitrogênio acumulado na parte aérea. Para nitrogênio derivado da fixação biológica verificou-se uma variação média de 49,42 a 65,50%. Nos componentes de produção, o Alagoano se destacou em massa de vagem, comprimento de vagem e massa de 100 sementes. Concluiu-se que os progenitores avaliados são responsivos a FBN e que há indícios de especificidade entre os progenitores e as estirpes de rizóbio. O progenitor Alagoano apresenta resultados mais promissores nos componentes de nodulação e produção.

Currently, cowpea growing covers three Brazilian regions, making essential the investigation of the magnitude of genotype x environment essential for choosing the best selection strategy and recommendation of cultivars. The aim of this study was to evaluate the adaptability and phenotypic stability of semi-prostate cowpea genotypes in sites from State of Mato Grosso do Sul based on different methodologies. We conducted four value of cultivation and use testing with lines and cultivars of cowpea genotypes in the years 2005 and 2006 in the municipalities of Aquidauana, Chapadão do Sul and Dourados. The experimental design was randomized complete block with 20 treatments and four replications. The grain yield data were submitted to individual and joint analysis of variance. Subsequently, data were submitted to adaptability and stability analysis by Eberhart and Russell (1966), Yates and Cochran (1938) (traditional) and Wricke (1965) methodologies. The genotypes BRS Xiquexique, TE97-304G-12, BR 17-Gurguéia and MNC99-541F-15 are the most suitable for growing in Mato Grosso do Sul by combine high yield grain, adaptability and phenotypic stability.

O objetivo deste trabalho foi avaliar a adaptabilidade e a estabilidade produtiva de genótipos de feijão-caupi (Vigna unguiculata) de porte semiprostrado. Foram avaliados 20 genótipos de feijão-caupi com uso do modelo de efeitos aditivos principais e interação multiplicativa (AMMI) com genótipo e ambiente suplementares. Os ensaios foram conduzidos em nove ambientes (Balsas, MA, 2010; Balsas, MA, 2011; Bom Jesus, PI, 2010; Bom Jesus, PI, 2011; São Raimundo das Mangabeiras, MA, 2010; São Raimundo das Mangabeiras, MA, 2011; São João do Piauí, PI, 2011; Campo Grande do Piauí, PI, 2011; Buriti, MA, 2011), da região Meio-Norte do Brasil, em delineamento de blocos ao acaso, com 20 tratamentos e quatro repetições. Os efeitos de genótipos, ambientes e da interação genótipo x ambiente foram significativos. Os genótipos diferiram quanto à adaptabilidade e à estabilidade da produtividade. A linhagem MNC03-736F-2 apresentou genes para adaptabilidade e estabilidade produtiva. Entre as cultivares avaliadas, BR 17-Gurguéia e Pingo-de-Ouro-1-2 são as mais previsíveis, e a BRS Xiquexique é a mais adaptada. Entre os locais de teste, Balsas, MA, é o mais adequado para a seleção de genótipos superiores em adaptabilidade e estabilidade produtiva.

The objective of this study was to estimate the direct and indirect effects of agronomic and culinary traits on iron and zinc contents in 11 cowpea populations. Correlations between traits were estimated and decomposed into direct and indirect effects using path analysis. For the study populations, breeding for larger grain size, higher number of grains per pod, grain yield, reduced cooking time, and number of days to flowering can lead to decreases in the levels of iron and zinc in the grain. Genetic gains for the iron content can be obtained by direct selection for protein content by indirect effects on the number of grains per pod, 100-grain weight and grain yield. The positive direct effect of grain size and protein content on the zinc content indicates the possibility of simultaneous gain by combined selection of these traits.

Cowpea is a crop that has become socio-economically relevant, mainly in developing countries. Correlation studies are important to determine the association between quantitative traits and yield to guide the selection, i.e., choose direct or indirect selection. The objective was to estimate the correlations between six agronomic traits in cowpea as well as the correlations between the estimates of combining abilities of parents. Genotypes with high pod weight and pod length, 100-grain weight, and number of beans per pod should be used to improve grain yield in cowpea. The breeder should preferably insert plants into his group of crosses that have a high combining ability for pod length, number of grains per pod and yield per plot.

O objetivo deste trabalho foi avaliar o potencial genético produtivo de progênies de feijão-caupi (Vigna unguiculata) segregantes quanto ao tipo da inflorescência. Foram avaliadas 68 progênies F4 obtidas dos retrocruzamentos: (TV x 5058-09C x Cacheado-roxo) x TV x 5058-09C e (AU94-MOB-816 x Cacheado-roxo) x AU94-MOB-816, com os genitores. Dois experimentos foram conduzidos no delineamento de blocos ao acaso, tendo-se avaliado 17 progênies, com quatro repetições, em parcelas subdivididas quanto à inflorescência: simples e composta. A análise estatística foi realizada por modelos mistos via procedimento REML/BLUP. As estimativas das variâncias genéticas foram significativas para todos os caracteres estudados. Os caracteres comprimento do pedúnculo, número médio de vagens por pedúnculo e floração inicial apresentaram alta variabilidade e expressão do componente genético para a inflorescência composta. As progênies de inflorescência simples apresentam potencial genético produtivo similar às progênies de inflorescência composta. As progênies resultantes do retrocruzamento (AU94-MOB-816 x Cacheado-roxo) x AU94-MOB-816 são promissoras como estratégia para aumentar os níveis atuais de produtividade do feijão-caupi.

O objetivo deste trabalho foi estimar parâmetros genéticos em caracteres associados com a produção de feijão fresco em 14 genótipos de feijão-caupi de vagem roxa e grãos brancos. Foram conduzidos três experimentos: dois sob irrigação (2004 e 2005) e um em condições de sequeiro (2005), no campo experimental da Embrapa Meio-Norte, em Teresina-PI, em delineamento de blocos completos casualizados com quatro repetições. Foram avaliados os seguintes caracteres: número de dias para a colheita de vagens frescas (NDCVF), comprimento de vagens frescas (CVF), número de grãos por vagem fresca (NGVF), peso de cem grãos frescos (P100GF), produtividade de vagens frescas (PVF), produtividade de grãos frescos (PGF), índice de grãos frescos (IGF), valor de cultivo (VC) e porte da planta (PP). As correlações genotípicas foram superiores às fenotípicas e ambientais, destacando-se as correlações entre VC e PVF (100%). O coeficiente de variação genético variou de 6,58% (IGF) a 31,62% (PGF), com destaque também para PVF (30,16%). No geral, todos os caracteres exibiram alto componente genético na expressão do caráter, com destaque para o CVF (98,72%). Existe um alto componente genético na expressão fenotípica de todos os caracteres estudados, com grande probabilidade de ganhos genéticos em ciclos adicionais de seleção com base no fenótipo. A seleção de genótipos de feijão-caupi de alta produtividade e precoces é mais fácil do que a seleção de genótipos de alta produtividade e tardios, para o melhoramento do feijão fresco.The aim of this work was to estimate genetic parameters in traits associated with the production of fresh southern pea in 14 cowpea genotypes of purple pod and white grains. Three experiments were carried out: two under irrigation (2004 and 2005) and one in rainfed conditions (2005), at Embrapa Mid-North experimental field, in a randomized complete block design with four replications. The correlations, genetic variation and determination coefficients were estimated for the following traits: number of days for the harvest of fresh seed (NDHFS), fresh pod length (FPL), number of seeds for fresh pod (NSFP), weight of one hundred fresh seed (WHFS), fresh pod yield (FPY), fresh seed yield (FSY), fresh seed index (FSI), value of crop (VC) and plant type (PT). The genotypic correlations were superior to phenotypic and environment correlations, being distinguished the correlations between VC and FPY (100%). The genetic variation coefficient varied from 6.58% (FSI) to 31.62% (FSY), with highlight also for FPY (30.16%). All characters showed high genetic component in the expression of the character, with highlight for the FPL (98.72%). There is a high genetic component in the phenotypic expression of all the traits studied, with a high probability of genetic gains in additional cycles of selection based on phenotype. Selection of cowpea genotypes for high yield and early is easier than selection of genotypes with high yield and late in the fresh southern pea breeding.

O objetivo deste trabalho foi estudar o controle genético do caráter comprimento do pedúnculo em feijão-caupi (Vigna unguiculata). Para isso, foi realizado um cruzamento entre os parentais TVx-5058-09C, de pedúnculo curto, e TE96-282-22G, de pedúnculo longo. Os parentais e as gerações F1, F2, RC1 (P1xF1) e RC2 (P2xF1) foram avaliados em delineamento de blocos ao acaso, com quatro repetições. Foram estimados: variâncias fenotípica, genotípica, ambiental, aditiva e de dominância; herdabilidades no sentido amplo e restrito; grau médio de dominância e número mínimo de genes que determinam o caráter. O modelo aditivo-dominante foi adequado para explicar a variação observada. O efeito gênico aditivo foi o mais importante no controle do comprimento do pedúnculo, que é, aparentemente, controlado por cinco genes.The objective of this work was to investigate the genetic control of peduncle length in cowpea (Vigna unguiculata L.). A short peduncle cowpea line (TVx-5058-09C) was crossed with a long peduncle line (TE 96-282-22G). The parents and the F1, F2, RC1 (P1xF1), and RC2 (P2xF1) generations were evaluated in randomized block design with four replications. Genotypic, phenotypic, environmental, additive, and dominance variances for peduncle length were determined. Narrow and broad sense heritability, the degree of dominance, and the minimum number of genes determining peduncle length were estimated. The additive-dominant model was adequate to explain the observed variation. The additive gene effect was the most important in controlling peduncle length, which appeared to be controlled by five genes.

O objetivo deste trabalho foi avaliar a adaptabilidade e a estabilidade da produtividade de grãos de 20 genótipos de feijão-caupi de porte semi-ereto, utilizando o modelo de efeitos aditivos principais e interação multiplicativa. Os ensaios foram conduzidos em 16 ambientes da Região Nordeste do Brasil. Os efeitos de genótipos, ambientes e da interação genótipo x ambiente, e os três primeiros eixos da análise de componentes principais (ACP) foram significativos. Os dois primeiros eixos da ACP explicaram juntos 55,11% da soma de quadrados da interação, correspondendo a 83,20% do padrão da interação genótipo x ambiente. As linhagens TE-97-321G-4, EVX-92-49E e EVX-63-10E apresentaram alta adaptabilidade, mas somente a última foi altamente previsível. A cultivar BRS Guariba e as linhagens EVX-92-49E e TE97-321G-4 expressam melhor potencial genético em ambientes de alta produtividade.The objective of this work was to evaluate the adaptability and the stability of the grain yield of 20 semierect cowpea genotypes, using the additive main effect and multiplicative interaction model. The trials were carried out in 16 environments of the Northeast Region of Brazil. The genotypes, environments and genotype x environment interaction, as well as the first three axes of the principal components analysis (PCA) were significant. The first two axes of the PCA explained 55.11% of the sum of squares of the genotype x environment interaction, corresponding to 83.20% of the pattern of genotype x environment interaction. TE97-321G-4, EVX-92-49E and EVX-63-10E lines were highly adaptable, but only the last one was highly predictable. BRS Guariba cultivar as well as EVX-92-49E and TE97-321G-4 lines best express their genetic potential in environments of high yield.

The phenotypical, genotypical and environmental variability and correlations in cowpea were estimated,aiming at the selection of lines for green-grain production. Both parents and 62 lines (39 F4, 16 F3BC1, 07 F3BC2) wereevaluated. The experiment was conducted in Teresina, Piauí, where the following traits were evaluated: stalk length; plantheight at flowering; number of nodes on the main stem; number of secondary branches; number of pods per plant; pod width,length and thickness; number of grains per pod; weight of 100 grains; and grain yield. The 14 lines of the F4 populationachieved high grain yields, with purple pods and white grains; they can be recommended for selection for green-grainproduction. Selection for more pods per plant may achieve a higher grain yield.

O objetivo deste trabalho foi avaliar a adaptabilidade e a estabilidade da produtividade de grãos de 15 genótipos de feijão-caupi (Vigna unguiculata) utilizando o modelo de efeitos principais aditivos e interação multiplicativa. Os ensaios foram conduzidos em 13 ambientes, nos Estados do Piaui e Maranhão, no período de 1999 a 2001. Os resultados mostraram a existência de poucas diferenças entre genótipos, mas os efeitos de ambientes, interação genótipos x ambientes e os três primeiros eixos da análise de componentes principais da interação foram altamente significativos (P

A estimação de parâmetros em gerações iniciais de endogamia tem importância para direcionar o programa de melhoramento, principalmente em relação ao processo de seleção dos genótipos mais promissores. Este trabalho avaliou 21 genótipos de soja (seis parentais e 15 combinações dialélicas em F2), em dois locais (ESALQ e Anhembi) de Piracicaba, SP. O delineamento usado foi em blocos ao acaso, com seis repetições por local. A parcela experimental foi de 12 covas de plantas individuais espaçadas de 0,80 m x 0,80 m. Os caracteres avaliados foram número de dias e altura da planta no florescimento e maturidade; valor agronômico; produtividade de grãos; teor de óleo na semente e produtividade de óleo. Todas as estimativas de parâmetros basearam-se nos componentes das análises de variância e covariância individuais e conjuntas. Parentais e F2 apresentaram variabilidade para todos os caracteres. Em termos de qualidade ambiental favorável, os dois locais foram bons para a expressão do potencial genético dos genótipos, no entanto, o local Anhembi foi mais favorável para produtividade de grãos. A interação genótipos x locais mostrou-se um importante componente da variação fenotípica, com exceção do caráter teor de óleo. As correlações genotípicas foram geralmente maiores que as fenotípicas e de ambiente nos dois locais. A magnitude das correlações fenotípicas e genotípicas mostrou que o fenótipo refletiu satisfatoriamente o genótipo. Os caracteres relacionados ao florescimento e à maturidade mostraram-se importantes para o melhoramento da produtividade, com destaque para o valor agronômico. Existe evidência de dificuldades em obter novos genótipos produtivos e precoces.

O melhoramento da soja (Glycine max) está avançado, porém, não se obteve atingir o seu limiar produtivo, a despeito de sua base genética restrita é esperado avanço significativo com o melhoramento genético na obtenção de novos cultivares com altos níveis produtivos. Objetivou-se com este trabalho investigar a interação genótipo x ambiente em soja por meio da análise de componentes principais com múltiplas matrizes de dados. Foram avaliados 44 e 23 genótipos, nos anos agrícolas 2000 e 2001, respectivamente. Utilizou-se o delineamento de blocos aos acaso, com duas repetições estratificadas em três conjuntos experimentais com testemunhas comuns (IAC 100, Ocepar 4, IAS 5 e Primavera). Os fatores considerados para a análise foram: genótipos (G1, G2, G3..., G44), ambientes (combinação dos locais Anhembi-AN e Areão-AR com o controle intensivo-COM e ecológico-SEM de insetos) e atributos (produção e componentes). O estudo foi implementado por meio de análise de componentes principais com arranjo de três entradas (genótipo x ambiente x variáveis). Os genótipos 2, 3, 23, 28, 36, 38 e 44 apresentam tolerância a percevejos e boa produtividade no ambiente AN_COM. Os genótipos 7, 17, 21, 29, 35, 37 e 40 interagem positivamente com o ambiente AR_SEM com adaptabilidades e estabilidades específicas redundando em produtividades elevadas.

The cupuaçuzeiro (Theobroma grandiflorum), species native from the Amazon region, has been domesticated presenting a broad genetic variability, and thus favorable conditions for establishing of strategies to breeding and genetic conservation. The aim of this work was to evaluate 36 half-sib progenies of Theobroma grandiflorum obtained from a stratified mass selection in farmers areas based on primary components of yield. The experiment for selection of elite progenies was set up in a randomized complete block design with three replications and four plants per plot. The fruit traits (length and width, in cm) and components of production (average weight of fruit/plant; average weight of pulp with seeds/plant and average weight of pulp/plant, in g) were evaluated. The data were analyzed through the methodology of REML/BLUP using the Selegen software. Analysis of grouping was performed using the matrix of genetic euclidean distances and Mahalanobis. The experimental population allowed the selection of superior parents for formation of base population to be used in the genetic improvement of cupuaçu. Among the 36 analyzed lineages only the genotypes 9, 10 and 18 showed genetic divergence and they can be recommended with some lineage of group 1 that demonstrates agronomic superiority to form base population of experimental clones with high genetic dissimilarity.doi: 10.4336/2011.pfb.31.66.123O cupuaçuzeiro, espécie nativa da região Amazônica, encontra-se em processo de domesticação, apresentando ampla variabilidade genética e condições favoráveis para o estabelecimento de estratégias de melhoramento e conservação. O objetivo foi avaliar geneticamente 36 progênies de meios-irmãos de cupuaçu oriundos de seleção massal estratificada em áreas de produtores, com base nos componentes primários da produtividade. O experimento para seleção das progênies superiores foi instalado no delineamento aleatorizado em blocos, com quatro plantas por parcela e três repetições. Foram consideradas as variáveis de caracterização do fruto (comprimento e largura, ambos em centímetro) e componentes de produção avaliados em grama (peso médio de fruto por planta, peso médio de polpa com sementes por planta e peso médio de polpa por planta). Os dados foram analisados através da metodologia REML/BLUP com o emprego do software Selegen. Para realizar o agrupamento, utilizaram-se matrizes de distâncias euclidianas genéticas e de Mahalanobis. A população experimental possibilitou a seleção de parentais superiores para formação de população base para o melhoramento genético do cupuaçu. Das 36 progênies analisadas, apenas as progênies 9, 10 e 18 mostraram divergência genética, podendo ser recomendadas juntamente com alguma progênie do grupo 1 que mostrar superioridade agronômica para formar população base de clones experimentais com alta dissimilaridade genética.doi: 10.4336/2011.pfb.31.66.123

O cupuaçuzeiro, espécie nativa da região Amazônica, encontra-se em processo de domesticação, apresentando ampla variabilidade genética e condições favoráveis para o estabelecimento de estratégias de melhoramento e conservação. O objetivo foi avaliar geneticamente 36 progênies de meios-irmãos de cupuaçu oriundos de seleção massal estratificada em áreas de produtores, com base nos componentes primários da produtividade. O experimento para seleção das progênies superiores foi instalado no delineamento aleatorizado em blocos, com quatro plantas por parcela e três repetições. Foram consideradas as variáveis de caracterização do fruto (comprimento e largura, ambos em centímetro) e componentes de produção avaliados em grama (peso médio de fruto por planta, peso médio de polpa com sementes por planta e peso médio de polpa por planta). Os dados foram analisados através da metodologia REML/BLUP com o emprego do software Selegen. Para realizar o agrupamento, utilizaram-se matrizes de distâncias euclidianas genéticas e de Mahalanobis. A população experimental possibilitou a seleção de parentais superiores para formação de população base para o melhoramento genético do cupuaçu. Das 36 progênies analisadas, apenas as progênies 9, 10 e 18 mostraram divergência genética, podendo ser recomendadas juntamente com alguma progênie do grupo 1 que mostrar superioridade agronômica para formar população base de clones experimentais com alta dissimilaridade genética. doi: 10.4336/2011.pfb.31.66.123

ABSTRACT Cowpea is grown in different environmental conditions of the Northeast region of Brazil. Thus, selecting and developing cultivars with high yield, stability, and adaptability for this region is necessary due to the genotype × environment interaction. The objective of this work was to select cowpea lines of semi-prostrate plant simultaneously for high yield, adaptability, and genotypic stability in the Northeast region of Brazil by the REML/BLUP procedure. Twenty semi-prostrate genotypes-16 lines and four cultivars-were evaluated in 36 environments of the Northeast region from 2013-2015. The experiments were carried out under rainfed conditions in a completely randomized block design with four replications. The adaptability and genotypic stability were evaluated by the REML/BLUP procedure. The genotype × environment interaction was complex-type, with the grain yield ranging from 260 kg ha-1 (Campo Grande do Piauí PI, 2015) to 2,764 kg ha-1 (Araripina PE, 2015), with overall mean of 1,304 kg ha-1. According to the Harmonic Mean of Relative Performance of Genetic Values (HMRPGV) estimates, the cultivars BRS Marataoã and BRS Pajeú and the line MNC04-792F-129 had simultaneously high yield, adaptability, and genotypic stability, and can be recommended and grown with greater probability of success in all the environments of the Northeast region of Brazil.

ABSTRACT The effects of the genotype × environment interaction can be reduced by using cultivars with high adaptability and good yield stability. Studies on this subject allow identification of genotypes of predictable behavior, and responsive to environmental variations in specific and general conditions, in favorable or unfavorable environments. The objective of this work was to evaluate the adaptability and phenotypic stability of cowpea elite lines of semi-prostrate growth habit in the Cerrado biome in Brazil. Twenty cowpea genotypes of semi-prostrate growth habit were evaluated in nine VCU (value for cultivation and use) tests from 2010 to 2012. Grain yield data were subjected to analysis of variance, and stability and adaptability analyses were carried out by the methods of Eberhart and Russell (1966), Lin and Binns (1988) (modified), Wricke (1965), and Annicchiarico (1992). The method of Wricke (1965) was not very descriptive, since it indicates only the contribution of each genotype to the genotype × environment interaction. The results obtained by the methods of Lin and Binns (1988) (modified), Annicchiarico (1992) and Eberhart and Russell (1966) were more descriptive, and similar in indicating the most promising cultivar (BRS-Xiquexique) and lines (Pingo-de-Ouro-1-2, MNC02-676F-1, MNC01-649F-2-1 and MNC02-677F-2). These lines have potential for the development of new cultivars because they present adaptability and yield stability in the Cerrado biome of Brazil.

Devido à variabilidade das leguminosas quanto à eficiência da fixação biológica de nitrogênio (FBN), tem sido enfatizada a importância do melhoramento genético vegetal no favorecimento da fixação do nitrogênio. Este estudo teve como objetivo avaliar a eficiência simbiótica de progenitores de cultivares brasileiras de feijão-caupi e dar suporte científico à inclusão da FBN ao programa de melhoramento genético da cultura do feijão-caupi no Brasil. O experimento foi conduzido em Teresina, Piauí. Utilizou-se delineamento experimental em blocos casualizados em esquema fatorial 6 x 5, com três repetições, sendo seis fontes de N: quatro estirpes de bactérias diazotróficas (BR 3267, BR 3299, BR 3262 e INPA 03-11B), um tratamento com nitrogênio mineral e outro sem inoculação e sem N; e cinco genótipos de feijão-caupi: quatro progenitores (TVu 1190, Pitiúba, CNC 0434 e Alagoano) e uma cultivar (BRS Guariba). Na análise de variância utilizou-se software SAS e as médias foram comparadas pelo teste Tukey. O progenitor Alagoano destacou-se dos demais em eficiência de nodulação, foi superior ao Pitiúba em massa seca de nódulos e diferiu do TVu 1190 em nitrogênio acumulado na parte aérea. Para nitrogênio derivado da fixação biológica verificou-se uma variação média de 49,42 a 65,50%. Nos componentes de produção, o Alagoano se destacou em massa de vagem, comprimento de vagem e massa de 100 sementes. Concluiu-se que os progenitores avaliados são responsivos a FBN e que há indícios de especificidade entre os progenitores e as estirpes de rizóbio. O progenitor Alagoano apresenta resultados mais promissores nos componentes de nodulação e produção.

ABSTRACT The aim of this study was to evaluate morpho-physiological and productive characteristics in four semi-erect cultivars of the cowpea under five plant populations. The experiment was conducted in the experimental area of Embrapa Meio-Norte in Teresina in the State of Piauí, Brazil (PI). The experimental design was of randomised complete blocks with four replications, in a 4 x 5 factorial scheme, for evaluating four cultivars (BRS Guariba, BRS Novaera, BRS Potengi and BRS Tumucumaque) and five plant populations (105, 2x105, 3x105, 4x105 and 5x105 plants ha-1). There were significant differences between cultivars for primary branch length (PBL), number of lateral branches (NLB), 100-grain weight (HGW), and dry-grain yield (GY). The maximum PBL of 58.5 cm was obtained with 300 thousand plants ha-1, corresponding to an increase of 11.5% when compared to 100 thousand plants ha-1. However, there was a reduction of 91.2% in NLB when compared to the populations of 100 and 500 thousand plants ha-1. The increases of 188% obtained in the leaf area index (LAI) in the range of 100 to 500 thousand plants ha-1 explain the linear increase in the crop growth rate (CGR) as being due to the greater production of leaf area; also, the decreases seen in the net assimilation rate (NAR), especially in the range of 100 to 300 thousand plants ha-1, are explained as due to the consequent self-shading, which was intensified in the larger populations. LAI, light interception, and CGR in the cultivars increase in response to higher densities. HGW and GY are not significantly affected by the different populations.

ABSTRACT Cowpea is grown in the various soil and climatic conditions of the Northeast region of Brazil. Thus, selecting and developing cultivars with high yield, stability, and adaptability for this region is necessary due to the genotype × environment interaction. The objective of this work was to select cowpea lines of semi-erect plant simultaneously for high yield, adaptability, and genotypic stability in the Northeast region of Brazil by the REML/BLUP procedure. Twenty semi-erect genotypes-15 lines and five cultivars-were evaluated in 37 environments of the Northeast region from 2013-2015. The experiments were carried out under rainfed conditions in a randomized complete block design with four replications. The adaptability and genotypic stability were evaluated by the REML/BLUP procedure. The environmental variance was the largest factor in the phenotypic variance and the genotype × environment interaction was complex-type, with a grain yield ranging from 277 kg ha-1 (Serra Talhada PE, 2015) to 2,845 kg ha-1 (São Raimundo das Mangabeiras MA, 2013), and an overall mean of 1,342 kg ha-1. According to the Harmonic Mean of Relative Performance of Genetic Values (HMRPGV) estimates, the lines MNC04-795F-153 and MNC04-795F-159 were those that simultaneously had high yield, adaptability, and genotypic stability, and can be recommended and grown with greater probability of success in the evaluated environments in the Northeast region of Brazil.

ABSTRACT The objective of this work was to use different selection criteria to identify cowpea genotypes tolerant to water deficit to be used in recurrent selection programs aiming to reduce the cowpea crop cycle and improve its productive components. Six cowpea genotypes were crossed in a complete diallel scheme. The experiment was conducted in an incomplete block experimental design in a triple lattice arrangement, with the 30 F2 populations of cowpea. The genetic variability of 10 traits was verified, and the following selection criteria were used: direct and indirect selection, classical index, index based on desired gains, and index based on sum of ranks. The number of days to flowering (NDF), number of days to maturity (NDMD), pod weight (PW), grain weight per pod (GWP) and 100-grain weight (100GW) were classified as primary traits, and the others as secondary. The direct selection based on the pod weight was the most efficient criterion to reduce the crop cycle and improve productive components of the cowpea genotypes subjected to water deficit conditions. The genotypes Pingo-de-Ouro-1-2 × MNC99-510F-16-1, CNCx698-128G × MNC99-510F-16-1, MNC99-510F-16-1 × Pingo-de-Ouro-1-2, Pingo-de-Ouro-1-2 × BRS Paraguaçu, Santo-Inácio × Pingo-de-Ouro-1-2, BRS Xiquexique × Pingo-de-Ouro-1-2 and Pingo-de-Ouro-1-2 × Santo-Inácio were the most suitable to be used in interpopulation recurrent selection programs aiming to reduce the crop cycle and improve productive components of cowpea grown under water deficit conditions.

ABSTRACT The cowpea (Vigna unguiculata (L.) Walp.) is one of the most widely consumed legumes in the North and Northeast of Brazil, representing an important source of protein, energy, fibre and minerals, in addition to generating employment and income. The aim of this study was to determine the chemical composition, and the effect of thermal processing on the green grain from biofortified cowpea cultivars. Samples of green grain from four cowpea cultivars were analysed, only one not being biofortified (standard). Centesimal composition and total energy value (TEV) were determined before and after thermal processing. The mean values of the characteristics under evaluation were compared by Student's t-test and Tukey's test (.

ABSTRACT Biofortification is a strategy that aims to improve the nutritional quality of foods through genetic breeding. Zinc is an important mineral for human health. It is used in various physiological processes such as immune function, antioxidant protection, growth and development. Therefore, zinc is one of the most studied minerals in the biofortification of grains in cowpea. The objective of this study was to evaluate the adaptability and stability of zinc density in the grain of 12 cowpea genotypes in four environments in the states of Piauí (PI) and Maranhão (MA), Brazil, by using the GGE-Biplot method. A randomized complete block design with four replications was used. Grain samples of each genotype were ground and the resulting flour was subjected to zinc density analysis by using an atomic flame absorption spectrophotometer. Analyses of variance were performed, and the adaptability and stability of zinc density in the grain was evaluated by the GGE-Biplot method. Genotypes showed different behavior depending on the environments tested for zinc concentration. According the GGE-Biplot method, Parnaiba-PI was the most discriminating environment for genotypes. Campo Grande do Piauí-PI and Parnaíba-PI were the most representative environments for selecting genotypes with zinc biofortification in the state of Piauí. Parnaíba-PI was the optimal environment for selection of genotypes adapted to high zinc density in grain. The cultivar BRS Xiquexique was the ideal genotype due to the high zinc density in the grain and high stability according to GGE-Biplot, followed by the lines MNC04-774F-78 and MNC04-782F-108.

ABSTRACT The black-eyed cowpea, is consumed in Brazil and valued in various other countries, and for this reason, can be found on the domestic market, showing the potential for export. The aim of this study was to identify lines of the black-eyed cowpea having high productivity and quality commercial grain. Twenty-four lines of black-eyed commercial subclass of cowpea, taken from the breeding program of Embrapa Meio-Norte, and two controls (BRS Itaim and CB-27) were evaluated. The experiments were carried out in Nova Ubiratã, in the State of Mato Grosso, Brazil (MT) during 2014, and in Primavera do Leste MT and Sinop MT during 2015, in the off-season; planting was in February/March and harvesting in May/June. The experimental design was of randomised complete blocks with four replications, in plots of 4 rows of 5 metres spaced 0.45 metres apart. Crop value, lodging and grain productivity were evaluated. The occurrence of blemished grain was also assessed, both by counting the blemished grain (visual selection), and by colorimetric analysis, using the CIE L* a* b* colour scale. Four lines showed potential for inclusion in the trials for crop value and use (VCU) as per the recommendation of the State of Mato Grosso, by combining grain productivity comparable to that of the BRS Itaim cultivar and a low percentage of blemished grain. Visual evaluation by counting the blemished grain, was efficient in identifying lines of the black-eyed cowpea with better grain quality in relation to the BRS Itaim cultivar. Colour reading using the CIE L* a* b* scale did not satisfactorily differentiate the occurrence of blemished grain in lines of the black-eyed cowpea.

ABSTRACT The present study evaluated the effect of cooking on the levels of bioactives compounds and antioxidant activity in grains cowpea cultivars. The analysis were performed on the raw samples and after cooking in pressure cooker. Regarding the bioactive compounds present, the grain cultivar BRS Aracê exhibited the highest levels of total phenolic compounds (mg/100 g) both before and after cooking, 205.10 ± 2.89 and 150.62 ± 2.64, respectively. Spermine and spermidine were identified in the cultivars (mg/kg) BRS Milênio in the amount of 120.5 in crude and 50.4 in cooked grain, in the BRS Tumucumaque in the amount of 116.2 in crude and 47.9 in cooked grain, exhibited significant losses of these compounds after cooking. It was not detected the presence of anthocyanins and flavonoids in the grain cultivars. For the antioxidant activity were observed different behaviors for each grain cultivar in the two methods evaluated. The grain cultivar BRS Aracê presented the highest antioxidant activity before cooking according to both methods tested (µmol TEAC/100 g), 614.7 ± 5.43 (DPPH) and 660.1 ± 7.98 (ABTS). The grain cultivar BRS Xiquexique 419.8 ± 6.80 exhibited the highest antioxidant activity and the grain cultivar BRS Milênio 552.1 ± 4.78 after cooking. A strong correlation between the antioxidant activity and phenolic content and total flavonoid was found. It is concluded that the grains cultivars maintained important nutritional and functional characteristics following processing, recommending that the cowpea consumption with broth cooking for retaining compounds with antioxidant properties.

ABSTRACT Cowpea grain is noteworthy due to its functional properties, which are probably a result of the synergistic action of its nutrients and bioactive compounds. Since these compounds undergo the effects of thermal processing, the aim of the present study was to verify the influence of cooking on the total polyphenol content of the grain of cowpea cultivars. Samples were obtained from the experimental area of Embrapa Meio-Norte, located at 5°5' S and 42°48' W, at an altitude of 72 metres. Meal (0.5 mesh) resulting from the raw grain being ground in a cyclone rotor mill (Tecnal model TE-651/2-T), and cooked beans (with no maceration, at a bean to water ratio of 1:5 (w/v), cooked in a domestic pressure cooker (2 L) for 780 seconds) were stored in airtight containers under refrigeration (8 °C) for analysis, which was carried out in triplicate. Total phenolic content was determined by spectrophotometry (λ = 765 nm), using Folin-Ciocalteau reagent. The total phenolic content, mg GAE (gallic acid equivalent)/100g, in the raw grain of the BRS Marataoã, BR 17-Gurguéia, BRS Itaim, BRS Cauamé and BRS Guariba cultivars was 295.23, 255.67, 132.32, 98.14 and 89.43 respectively. After cooking, the content was 405.87, 255.4, 161.71, 127.79 and 111.92 respectively, considering both grain and broth. This rise may have been the result of increased solubilisation and extraction of the compounds, due to the softening or rupture of the plant cells. It was concluded that, considering both grain and broth, the total phenolic content increased after cooking; the BRS Marataoã and BR 17-Gurguéia cultivars showed the highest levels.