Independent segregation of qualitative traits and estimation of genetic parameters and gene action for some quantitative traits in guar (Cyamopsis tetragonoloba L. Taub.)

Abstract

Current study was undertaken to elucidate the inheritance qualitative traits namely, flower colour and leaf hairiness in two F2 populations comprising of 194 and 99 individuals with reference to yield and agronomic traits along with genetic parameters. The violet colour of flowers and leaf hairiness were dominant over white flower and smooth leaves, respectively. The χ 2 -test revealed independent single gene inheritance for both the traits with joint segregation ratio of 9:3:3:1 in F2 . Except for no. of pods per cluster and pods per plant, both parents (Smooth 25 and HG2-20) exhibited significant (p < 0.05) differences for traits under investigation. A higher estimate of phenotypic coefficient of variance (PCV) than genonotypic coefficient of variance (GCV) was recorded for all the characters except test weight and clusters on branches. The heritability ranged from 24.36% (seeds per pod) to 92.32% (clusters on branches). Gene action as per skewness indicated that both duplicate and complementary interactions were playing role in the development of various traits, whereas, inheritance analysis as per kurtosis suggested that traits were oligogenic. Eventually, it can be concluded that high GCV, appearance of transgressive segregants and involvement of fewer major genes in defining the quantitative traits including yield, provided an opportunity for their genetic improvement.