Revealing the gene action of puffing-associated traits in rice (Oryza sativa L.) through generation mean analysis

Rice is the primary source of nutrition for billions of people and is one of the world's oldest and most significant staple foods. In addition to yield, it is equally essential to preserve quality. Puffed rice is a traditional, affordable and widely available prebiotic cuisine that stands out among the numerous rice-based products. A more profound comprehension of the genetic factors and physicochemical properties influencing puffing yield can significantly enhance production efficiency. The present study elucidates the genetics of 14 traits viz. days to initial flowering (DF), panicle length (PL), number of productive tillers per plant (NPT), number of filled grains per panicle (NFG), kernel length (KL), kernel breadth (KB), kernel L/B ratio (L/B ratio), plant height (PH), test weight (TW), single plant yield (SPY), puffing yield (PY), bulk density (BD), expansion volume (EV), expansion ratio (ER) by employing generation mean analysis in two crosses (Kuliyadichan × ASD 19 and ACK 15004 × Bhavani). The individual scaling and joint scaling tests were used to evaluate the adequacy of the additive dominance mode in addition to testing in the A, B, C and D scales. Epistatic interaction was observed for DF, PH, NPT, PL, NFG, puffing yield and KL of both crosses. Duplicate epistasis was predominant for the traits such as, PL, number of productive tillers, number of filled grains/ panicle, KL, L/B ratio, PH, TW, puffing yield and BD. Meanwhile, the traits such as KB and SPY showed complementary epistasis. Traits governed by epistatic gene action can be improved when the selection process is delayed until later generations are born. However, selection for traits governed by additive gene action can be effectively practised at the early breeding stages.