Kaesel Jackson Damasceno-Silva

DESEMPENHO DE LINHAGENS ELITE DE FEIJÃO-CAUPI EM AMBIENTES DE MINAS GERAIS E MATO GROSSO

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<0.05). The plant growth habit, lodging, cultivation value, pod length and bean yield were evaluated. The lines MNC04768F-21 and MNC04F-795F-168 had the highest bean yield in the experiments conducted in Mato Grosso, and their growth habit, lodging and cultivation value were similar to those of the cultivar BRS-Guariba. The lines MNC04-769F-30, MNC05-795F-154 and MNC04-769F-49 and the cultivar BRS-Tumucumaque had the highest bean yield in the experiments conducted in Minas Gerais. However, the cultivars BRS-Guariba, BRSTumucumaque, BRS-Novaera, BRS-Itaim and BRS-Cauamé and the lines MNC04-792F-143 and MNC04792F-144 showed satisfactory bean yield and good growth habit, plant lodging and cultivation value in the State of Minas Gerais, especially in the northern region of the state (Jaíba and Janaúba), representing good alternatives for the genotypes recommended for this region.

CARACTERIZAÇÃO QUÍMICA, GRANULOMÉTRICA E TECNOLÓGICA DE FARINHAS INTEGRAIS DE CULTIVARES COMERCIAIS DE FEIJÃO-CAUPI

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, TE651/2) 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 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.

Selection of cowpea populations tolerant to water deficit by selection index

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 Paraguacu, Santo-Inacio × Pingo-de-Ouro-1-2, BRS Xiquexique × Pingo-de-Ouro-1-2 and Pingo-de-Ouro-1-2 × Santo-Inacio 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.

Adaptability and yield stability of cowpea elite lines of semi-prostrate growth habit in the cerrado biome

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.

Genotype x environment interaction in cowpea by mixed models

Several methods have been proposed to measure effects of genotype × environment interaction (G×E) on various traits of interest of plant species, such as grain yield. Among these methods, mixed models using the Restricted Maximum Likelihood (REML)-Best Linear Unbiased Prediction (BLUP) procedure with random genotype effects have been reported as advantageous, since they allow the obtaining of actual genotypic values for cultivation and use. The objective of this work was to evaluate the response of grain yield to different locations and years, and the effects of G×E on the performance of cowpea genotypes by the methodology of mixed models. Twenty genotypes were evaluated under rainfed conditions in 47 locations in 2010, 2011 and 2012 using randomized block design. After joint analysis, the genotypes adaptability and stability patterns within and between years were tested by the Harmonic Mean of Relative Performance of Genetic Values (HMRPGV) statistics. The analysis within the years showed highly significant effects of the genotype × location interaction in all the years evaluated. The results of the joint analysis presented highly significant effects (p≤0.01) of the genotype, and triple interaction (genotype × location × year) (p≤0.001),xa0 denoting a strong effect of the G×E on the genotype performances. The HMRPGV analysis was adequate to identify superior genotypes, highlighting the MNC02-676F-3, MNC03-737F-5-1, MNC03-737F-5-9, BRS-Tumucumaque, and BRS-Guariba as the genotypes with best stability and highest grain yield. The selection of these genotypes resulted in a new average yield (1,402 kg ha-1) which is higher than that obtained by selection based only on the phenotype (1,230 kg ha-1).

Yield adaptability and stability of semi-prostrate cowpea genotypes in the Northeast region of Brazil by REML/BLUP

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 (Sao 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.

Adaptability and stability of the zinc density in cowpea genotypes through GGE-Biplot method

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 Piaui (PI) and Maranhao (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 Piaui-PI and Parnaiba-PI were the most representative environments for selecting genotypes with zinc biofortification in the state of Piaui. Parnaiba-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.

TOLERÂNCIA AO DÉFICIT HÍDRICO EM POPULAÇÕES F2 DE FEIJÃO-CAUPI

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-698128G, 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.

SELEÇÃO SIMULTÂNEA PARA DESENVOLVIMENTO DE LINHAGENS DE FEIJÃO-CAUPI DE PORTE ERETO E DO TIPO FRADINHO

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 Federers 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.