<b>Genetics of the concentration of copper in common bean seeds</b> - doi: 10.4025/actasciagron.v35i3.16520

Abstract

ABSTRACT. The common bean (Phaseolus vulgaris L.) is an important source of copper in human nutrition. The objective of this research was to investigate the possible maternal effects on copper concentrations in the seeds of the common bean, to estimate the heritability and the selection gains in early hybrid generations for the characteristic of copper concentration and to evaluate the potential for genetic improvement. The controlled crossings were performed among IAPAR 44 x IAPAR 31 and Diamante Negro x TPS Bonito cultivars. The reciprocal F 1 , and F 2 generations, as well as the backcross populations, were produced by each hybrid combination. The range of variation in the copper concentration among the tested progenies was from 1.07 to 7.75 mg kg -1 dry matter, and no significant maternal effect was discovered. A narrow-sense heritability was of an intermediate (51.98%) to high (61.99%) value. A 46.78% increase in the copper concentration was obtained in the seeds using only the four parents tested in this study.Keywords: Phaseolus vulgaris, embryo, maternal effect, heritability, early generation.Genética da concentração de cobre em sementes de feijão comum RESUMO. O feijão comum (Phaseolus vulgaris L.) é uma importante fonte de cobre na nutrição humana. O objetivo deste trabalho foi investigar a existência de efeito materno para a concentração de cobre em sementes de feijão comum, estimar a herdabilidade e os ganhos na seleção em gerações precoces para o caráter concentração de cobre e avaliar o potencial para o melhoramento genético. Os cruzamentos controlados foram realizados entre as cultivares IAPAR 44 x IAPAR 31 e Diamante Negro x TPS Bonito. As gerações F 1, F 1 recíproco, F 2 e F 2 recíproco, bem como as populações de retrocruzamentos foram obtidas para cada combinação híbrida. A faixa de variação da concentração de cobre entre as progênies testadas foi de 1,07 a 7,75 mg kg -1 de matéria seca, e nenhum efeito materno significativo foi detectado. A herdabilidade em sentido restrito foi de intermediária (51,98%) a alta (61,99%). Um incremento de 46,78% foi obtido para a concentração de cobre nas sementes utilizando os quatro parentais testados nesse trabalho. Palavras-chave:Phaseolus vulgaris, embrião, efeito materno, herdabilidade, geração precoce.

Genetic parameters of agronomic and nutritional traits of common bean (Phaseolus vulgaris L.) populations with biofortified grains

“…However, in the F 2 generation, it was observed wide genetic variability for copper concentration in the recombinant obtained from crossings between the common bean cultivars IAPAR 44 × IAPAR 31, and between Diamante Negro × TPS Bonito (Poersch et al, 2013). In the present study, the variation coefficient obtained for copper concentration was of high magnitude (CV= 33.18%), providing low experimental accuracy, and it did not allow the differentiation between common bean inbred lines for this mineral.…”

“…Narrow-sense heritability was of high magnitude for phosphorus and copper concentrations in common bean grains in F 2 generations Poersch et al, 2013), and of low magnitude for potassium concentration .…”

“…Four common bean populations with biofortified grains for potassium (population 1 -P 1 ), phosphorus (population 2 -P 2 ), zinc (population 3 -P 3 ) and copper (population 4 -P 4 ) were obtained by Poersch et al (2011), Rosa et al (2010, and Poersch et al (2013), respectively. For this, controlled crossings were carried out between the cultivars IAPAR 44 × Guapo Brilhante, and BRS Expedito × BRS Valente (P 1 ), Pérola × Guapo Brilhante, and TPS Nobre × Guapo Brilhante (P 2 and P 3 ), and IAPAR 44 × IAPAR 31, and Diamante Negro × TPS Bonito (P 4 ) ( Table 1).…”

“…Common bean inbred lines with high iron and zinc concentrations in grains were obtained by plant breeding (Blair, 2013;Pereira et al, 2014;Teixeira et al, 2015). Preliminary studies showed that it was possible to increase phosphorus and copper concentrations in common bean grains in 19.17 and 46.78%, respectively, in F 2 generation Poersch et al, 2013). Since common bean is self-fertilizing, is it expected that these values are reduced in each self-fertilizing generation.…”

Genetic dissimilarity of common bean lines for agronomic and biofortification traits

“…Parents were selected based on high agronomic performance and contrasting concentrations of potassium (Poersch et al, 2011), phosphorus , zinc (Rosa et al, 2010), and copper in grains (Poersch et al, 2013). The parents and lines obtained are of the Mesoamerican gene pool and represent the types of grains most consumed in Brazil, Carioca (beige seed coat with brown streaks) and black.…”