REML/BLUP-based dissection of combining ability and maternal influence on soybean grain protein
Gabriel Mathias Weimer Bruinsma, Ivan Ricardo Carvalho, Christiane de Fátima Colet, Alessandro Dal’Col Lúcio, João Pedro Dalla Roza and Jaqueline Pieasanti Sangiovo
Abstract: This study aimed to analyze the additive and non-additive genetic effects governing protein content in soybean grains and to identify superior parents and maternal contributions in advanced generations. A total of 170 F8 soybean lines and 95 commercial cultivars were evaluated during the 2024/2025 growing season. The total protein content in the grains (%) was determined. Deviance analysis confirmed significant effects of general combining ability (GCA) and specific combining ability (SCA). Narrow-sense heritability was low (2%), while broad-sense heritability reached 52%, demonstrating total genetic variability, attributable to dominance and epistatic effects. The average overall crude protein content was 36.15%. The parents NS5958RR, Maradona, and
DM5.8BmxApoloRR showed the highest positive GCA estimates, indicating the presence of favorable additive alleles. The most promising specific combination was L77, with a 1.16% increase in protein, followed by L87. Maternal contributions were evident, particularly when NS5958RR and Maradona were used as female parents.