Controle genético da concentração de ferro em sementes de feijão comum mesoamericano e andino

The objective of this work was to evaluate the main differences in the genetic control of the iron concentration in Mesoamerican and Andean common bean seeds, in early generations, and to select recombinants with a high iron concentration in the seeds. F1, F1 reciprocal, F2, F2 reciprocal, and backcross (BC11 and BC11) generations were produced by crosses between Mesoamerican (CNFP 10104 x CHC 01‑175) and Andean (Cal 96 x Hooter) inbred lines. The expression of significant maternal effect was observed for the Mesoamerican gene pool. Iron concentration was higher in the seed coat of Mesoamerican common bean seeds (54.61 to 67.92%) and in the embryo of Andean common bean seeds (69.40 to 73.44%). High broad-sense heritability was obtained for iron concentration in Mesoamerican and Andean common bean seeds. Gains with the selection of higher magnitude, from 20.39 to 24.58%, are expected in Mesoamerican common bean seeds. Iron concentration in common bean seeds showed a continuous distribution in F2, which is characteristic of quantitative inheritance in Mesoamerican and Andean common bean seeds. Recombinants with high iron concentration in seeds can be selected in both Mesoamerican and Andean common bean hybrids.O objetivo deste trabalho foi avaliar as principais diferenças no controle genético da concentração de ferro em sementes de feijão comum mesoamericano e andino, em gerações precoces, e selecionar recombinantes com alta concentração de ferro nas sementes. Foram obtidas as gerações F1, F1 recíproco, F2, F2 recíproco e de retrocruzamentos (RC11 e RC12), a partir de cruzamentos entre linhagens mesoamericanas (CNFP 10104 x CHC 01‑175) e andinas (Cal 96 x Hooter). A expressão de efeito materno significativo foi observada no grupo gênico mesoamericano. A concentração de ferro foi maior no tegumento das sementes de feijão comum mesoamericano (54,61 a 67,92%) e no embrião das sementes de feijão comum andino (69,40 a 73,44%). Alta estimativa de herdabilidade no sentido amplo foi obtida para a concentração de ferro em sementes de feijão comum mesoamericano e andino. Ganhos com a seleção de maior magnitude, de 20,39 a 24,58%, são esperados nas sementes de feijão comum mesoamericano. A concentração de ferro nas sementes de feijão comum apresentou distribuição contínua em F2, o que é característico de herança quantitativa em feijão comum mesoamericano e andino. Recombinantes com alta concentração de ferro nas sementes podem ser selecionados nos híbridos de feijão comum mesoamericano e andino

Association between canopy high-throughput phenotyping and yield in soybean

A identificação de caracteres mensuráveis por meio da fenotipagem de alto rendimento e que sejam correlacionados com a produtividade de grãos pode ser de grande utilidade para os programas de melhoramento de soja. Os objetivos deste estudo foram quantificar a associação existente entre a qualidade fisiológica de sementes, a cobertura de dossel vegetativo e a produtividade de grãos em genótipos de soja. Para tanto, dois experimentos de campo foram conduzidos nas cidades de Mauá da Serra e Campo Mourão, Paraná, Brasil. Um total de 97 genótipos de soja foram analisados na safra agrícola de 2018/2019. Antes da semeadura, uma amostra das sementes, foi destinada a avaliação da qualidade fisiológica por meio de teste de germinação, teste de primeira contagem, comprimento de plântulas aos três dias, massa seca de plântulas aos três dias, emergência em areia, índice de velocidade de emergência e massa seca de plântulas em areia. A cobertura de dossel foi determinada com uso de uma câmera RGB acoplada a um drone Phantom 4 Pro. As imagens foram capturadas em voos realizados nos estádios fenológicos V3-V4, V5-V6, V7-V8 e V9-R1, que foram utilizadas para o cálculo da cobertura de dossel através da proporção de pixels verdes em cada parcela experimental. Além disso, foram determinadas as falhas presentes em cada parcela, em metros lineares. Os dados foram submetidos a análise de variância individual e conjunta, e análise de diversidade genética. As correlações genotípicas foram estimadas entre todos os caracteres avaliados em ambos os ambientes para a confecção de redes de correlações e análises de trilha. A qualidade de parcela, expressa pelo comprimento de falhas, foi correlacionada negativamente com os caracteres referentes a qualidade fisiológica de sementes e com a porcentagem da cobertura de dossel nos dois ambientes, mas não apresentou impacto sobre as estimativas de produtividade de grãos. Além disso, a qualidade fisiológica de sementes correlacionou-se positivamente com o desenvolvimento do dossel vegetativo. A produtividade de grãos em Campo Mourão, apresentou associação linear genotípica de 0,76 e efeito direto de 0,84 com a cobertura de dossel no estádio V9-R1, indicando que uma maior biomassa do dossel no florescimento proporciona maior produtividade de grãos. Para Mauá da Serra não foi constatado associação significativa de alta magnitude entre a cobertura de dossel e a produtividade de grãos. No entanto, é importante a realização de experimentos em mais locais para melhor entendimento a respeito do efeito ambiental sobre a relação entre cobertura de dossel e produtividade de grãos em soja.The identification of measurable traits using high-throughput phenotyping besides them being correlated with grain yield can be very useful for soybean breeding programs. This study aimed to quantify the association between seed physiological quality, vegetative canopy cover and grain yield in soybean genotypes. For that, two field experiments were carried out in the twons of Mauá da Serra and Campo Mourão, Paraná, Brazil. A total of 97 soybean genotypes were analyzed in the 2018/2019 crop seasons. Before sowing, a seed sample, was used to evaluate the physiological quality by means of germination test, first count test, seedling length at three days, dry mass of seedlings at three days, emergence in sand, emergency speed index and dry mass of seedlings in sand. The canopy cover was determined using an RGB camera mounted on a Phantom 4 Pro drone. The images were captured on flights carried out in phenological stages V3-V4, V5-V6, V7-V8 and V9-R1, which were used for the calculation of the canopy cover by the proportion of green pixels in each experimental plot. In addition, the row gaps present in each plot, in linear meters, were determined. The data were submitted to both individual and joint analysis of variance, along with analysis of genetic diversity. Genotypic correlations were estimated among all the characters evaluated in both environments in order to settle correlation networks and path analysis. The plot quality, expressed as failure length, was negatively correlated with the characteristics of the physiological seed quality and the percentage of canopy cover in both environments, but did not show any impact on grain yield estimates. In addition, the physiological quality of seeds correlated positively with vegetative canopy development. Grain yield in Campo Mourão, showed a genotypic linear association of 0.76 and a direct effect of 0.84 with the canopy cover in the V9-R1 stage, indicating that a higher canopy biomass in the flowering provides higher grain yield. For Mauá da Serra, no significant association of high magnitude was observed between canopy cover and grain yield. However, it is important to carry out experiments in more locations to better understand the environmental effect on the relationship between canopy cover and grain yield in soybean.Conselho Nacional de Desenvolvimento Científico e Tecnológic

Genetic control of iron concentration in Mesoamerican and Andean common bean seeds

The objective of this work was to evaluate the main differences in the genetic control of the iron concentration in Mesoamerican and Andean common bean seeds, in early generations, and to select recombinants with a high iron concentration in the seeds. F1, F1 reciprocal, F2, F2 reciprocal, and backcross (BC11 and BC12) generations were produced by crosses between Mesoamerican (CNFP 10104 x CHC 01-175) and Andean (Cal 96 x Hooter) inbred lines. The expression of significant maternal effect was observed for the Mesoamerican gene pool. Iron concentration was higher in the seed coat of Mesoamerican common bean seeds (54.61 to 67.92%) and in the embryo of Andean common bean seeds (69.40 to 73.44%). High broad-sense heritability was obtained for iron concentration in Mesoamerican and Andean common bean seeds. Gains with the selection of higher magnitude, from 20.39 to 24.58%, are expected in Mesoamerican common bean seeds. Iron concentration in common bean seeds showed a continuous distribution in F2, which is characteristic of quantitative inheritance in Mesoamerican and Andean common bean seeds. Recombinants with high iron concentration in seeds can be selected in both Mesoamerican and Andean common bean hybrids

Genetic control of iron concentration in Mesoamerican and Andean common bean seeds

The objective of this work was to evaluate the main differences in the genetic control of the iron concentration in Mesoamerican and Andean common bean seeds, in early generations, and to select recombinants with a high iron concentration in the seeds. F1, F1 reciprocal, F2, F2 reciprocal, and backcross (BC11 and BC12) generations were produced by crosses between Mesoamerican (CNFP 10104 x CHC 01-175) and Andean (Cal 96 x Hooter) inbred lines. The expression of significant maternal effect was observed for the Mesoamerican gene pool. Iron concentration was higher in the seed coat of Mesoamerican common bean seeds (54.61 to 67.92%) and in the embryo of Andean common bean seeds (69.40 to 73.44%). High broad-sense heritability was obtained for iron concentration in Mesoamerican and Andean common bean seeds. Gains with the selection of higher magnitude, from 20.39 to 24.58%, are expected in Mesoamerican common bean seeds. Iron concentration in common bean seeds showed a continuous distribution in F2, which is characteristic of quantitative inheritance in Mesoamerican and Andean common bean seeds. Recombinants with high iron concentration in seeds can be selected in both Mesoamerican and Andean common bean hybrids

Genetic parameters of iron and zinc concentrations in Andean common bean seeds

ABSTRACT. The genetic parameter estimates of the iron and zinc concentrations in Andean common bean seeds were obtained using the IAC Boreal × Light Red Kidney and Ouro Branco × Light Red Kidney crosses. The parents and the F1, F1 reciprocal, F2, F2 reciprocal, and backcross BC11 and BC12 generations were evaluated in a field experiment that was carried out in the state of Rio Grande do Sul, Brazil. The iron concentration in Andean common bean seeds ranged from 24.70 to 102.40 mg kg-1 dry matter (DM), the zinc concentration ranged from 10.73 to 37.50 mg kg-1 DM, and no significant maternal effect was observed. The narrow-sense heritability ranged from low (h2n= 19.04%) to high (h2n= 63.60%) for the concentrations of iron and zinc, respectively. Hybrid vigor and transgressive segregation were observed for the iron and zinc concentrations in Andean common bean seeds. In the hybrid combination IAC Boreal × Light Red Kidney, it was possible to select recombinants for the iron and zinc biofortification program. From the tested hybrid combinations, recombinants with low iron and zinc concentrations in seeds could be selected to use when the diet needs to be restricted in those minerals

Genetic parameters of iron and zinc concentrations in Andean common bean seeds

The genetic parameter estimates of the iron and zinc concentrations in Andean common bean seeds were obtained using the IAC Boreal × Light Red Kidney and Ouro Branco × Light Red Kidney crosses. The parents and the F1, F1 reciprocal, F2, F2 reciprocal, and backcross BC11 and BC12 generations were evaluated in a field experiment that was carried out in the state of Rio Grande do Sul, Brazil. The iron concentration in Andean common bean seeds ranged from 24.70 to 102.40 mg kg-1 dry matter (DM), the zinc concentration ranged from 10.73 to 37.50 mg kg-1 DM, and no significant maternal effect was observed. The narrow-sense heritability ranged from low (h2n= 19.04%) to high (h2n= 63.60%) for the concentrations of iron and zinc, respectively. Hybrid vigor and transgressive segregation were observed for the iron and zinc concentrations in Andean common bean seeds. In the hybrid combination IAC Boreal × Light Red Kidney, it was possible to select recombinants for the iron and zinc biofortification program. From the tested hybrid combinations, recombinants with low iron and zinc concentrations in seeds could be selected to use when the diet needs to be restricted in those minerals.

Selecting tropical wheat genotypes through combining ability analysis

Abstract The selection of parents to originate promising base populations, as well as the knowledge of the gene effects controlling agronomic traits by means of diallel, are useful to drive genetic gains in Brazilian tropical wheat breeding programs. The goals of this study were to select tropical wheat parents with a high frequency of favorable alleles and segregating populations with high potential to originate superior progenies through partial diallel analysis. Thus, 14 parents were divided in two groups and crossed in a 7 × 7 partial diallel scheme to originate 49 F1 combinations. After obtaining F2 generation, the populations and the parents were evaluated in the field in the summer of 2021. Days for heading, plant height, rust and yellow spot resistance, and grain yield were evaluated. The data were subjected to partial diallel analysis. There were significant effects of general combining ability for all traits. The specific combining ability effect was significant for days for heading and plant height. The additive gene effects were predominant over the non-additive ones. The parents with the highest frequency of favorable alleles for the traits evaluated were selected in each group. Four populations with high genetic potential to originate superior progenies were selected