Gene effects, heterosis and inbreeding depression for grain sorghum characters

• Autor(a) principal: Scapim, Carlos Alberto
• Data de Publicação: 1998
• Outros Autores: Santos Rodrigues, José Avelino, Cruz, Cosme Damião, Araújo Gomes, Jerônimo, de Lucca e Braccini, Alessandro
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Pesquisa Agropecuária Brasileira (Online)
• Texto Completo: https://seer.sct.embrapa.br/index.php/pab/article/view/5016
• topic: Sorghum bicolor; gene action; hybrid vigor; Sorghum bicolor; ação gênica; vigor híbrido

Two crosses between grain sorghum (Sorghum bicolor L. Moench), BR 007A x BR 012R and BR 001A x BR 012R originated two F1 hybrids (BR 303 and BR 304) and the advanced inbreeding generations F2 and F3, establishing nine genotypes, which were evaluated in two planting dates (normal and succession). Several yield and forage quality characters were evaluated. The objectives of this study were to obtain the estimated heterosis and inbreeding depression in F2 and F3 generations, to evaluate the possibility of F2 seeds use in commercial sown, to verify also the estimated gene effects associated to heterosis and inbreeding depression. In sucession planting, comparing with normal planting, the grain sorghum hybrids showed small grain production, green matter and dry matter weight and higher protein content. For the two grain sorghum hybrids, the estimated heterosis was positive to grain yield and dry matter and was negative to protein and fiber content, at the two planting date. The estimated inbreeding depression was positive to grain yield, making impossible the commercial utilization of F2 seeds. The estimated additive gene effects had importance to quality characters in grain cross BR 007A x BR 012R, while the dominance effects were predominant to yield characters of the two hybrids and planting dates. The dominance effects explained most of the heterosis and inbreeding depression expressed of several characters in two crosses.