Evaluation of TGMS lines for good floral and out crossing related traits in rice

Abstract

The objective of present study is to identify promising TGMS lines with desirable floral and out crossing related traits for hybrid rice breeding. A total of seven new TGMS lines were raised during summer 2017 and observed under sterility favouring environment for tgms gene expression. Out of seven TGMS lines, four lines showed the stable performance and two TGMS lines viz., TNAU45S,TNAU60S were shown completely pollen sterile throughout the summer. Variability studies revealed that the characters viz., glume angle, stigma exertion percent and out-crossing per cent showing high GCV, Heritability and Genetic advance could be effectively utilized in selection. Correlation studies showed that the trait glume angle exhibited significant and positive correlation with extent of out crossing and spikelet sterility percent. The four TGMS lines viz., TNAU 39S, TNAU 45S, TNAU 60S, TNAU 95S registered the highest value for angle of glume opening (> 35%), panicle exertion percentage (> 90%) and stigma exertion percentage (> 65%). These lines had wider sterility expression period with very good floral traits viz., higher pollen sterility per cent, panicle and stigma exertion per cent, wider glume opening favorable for enhanced out-crossing rate and seed set percentage during seed production. From this study, the TGMS lines TNAU 39S, TNAU 45S, TNAU 60S and TNAU 95S were identified as promising based on floral and out crossing related traits and will be utilized for future hybrid breeding programmes towards the development of two line hybrids.