Transgressive Segregation in F2:7 Triticale Families

Abstract

Transgressive segregation in self-pollinated plants is important for the derivation of new varieties with better characteristics. The objective of this research was to evaluate the transgressive segregation in 26 families F2:7 triticale from different female parents of crosses between spring and intermediate habit and a common male ancestor of win ter habit, for production traits leaf biomass, total biomass and grain yield under three environments and to identify families that confer increased productivity under environmental stresses. Analysis of in dividual and combined environment variance between environments and mean comparison tests were conducted for each variable, using the Tukey test at (p<0.05) probability. Analysis of orthogonal contrast between families and parents’ groups were done. The analysis of vari ance showed differences (p<0.01) and (p<0.05) between treatments for total biomass and grain yield in the three environments. The com bined analysis showed statistical differences in environments and treatments for the three variables, the mean test environments also showed differences between the three variables and the mean test between combined treatments did not register differences for leaf biomass. The contrast analysis registered little differences between families and parents; however, there were families who had more than 50% of transgressive genotypes, which showed positive transgres sion based on their best parent for the three variables and maintained their transgression across the three environments. We conclude that the transgressive segregation occurs in advanced families F2:7 of triticale for these variables and it is an important tool for the improve ment of this crop under environmental stress furthermore, crosses between spring and late materials allows the occurrence of positive transgressive.