Assessment of Combining ability for some Grain Yield and Quality Traits in Rice (Oryza sativa L.) by using Griffing Method and Biplot Analysis

Abstract

During 2017 growing season, half diallel crosses were made among six genotypes of rice. The obtained 15 F1 and their parents were evaluated during 2018 growing season to analyze the general combining ability (GCA) and specific combining ability (SCA). For all studied characters, the mean squares due to GCA and SCA were highly significant, indicating the importance of the behaviour of both additive and dominance gene in the heredity of these characters. Variances due to GCA were greater than these due to SCA for all studied traits, except milling and grain elongation. Giza 178 and Giza179 possessed highly significant GCA effects for earliness, panicle length, number of filled grains panicle-1, grain yield plant-1 and hulling. IET1444 was good combiner for cooking traits, beside panicle length and number of tillers plant-1. Seven crosses viz., Giza178xIET1444, Sakha 106x Giza 179, Sakha 105x Giza 179, IET1444x WAB880-SG, Giza178xGiza179, Sakha105xSakha106, and Sakha105xGiza178 evidence positive and significant SCA effects for grain yield plant-1. The cross, Sakha 105xGiza179 recorded significant SCA effect in favourable direction for seven traits viz., days to 50%heading, panicle length, number of filled grains/panicles, grain yield plant-1, milling, grain elongation, and amylose content. Sakha105x Sakha106 rice hybrid showed desirable either negative or positive directions and significant SCA effects for days to 50%heading, plant height, grain yield plant-1, gelatinization temperature and grain elongation. Concerning results obtained by biplot analysis, found agreement between two methods of griffing and biplot for analyzing the half-diallel in determining the best parents and hybrids.