Development of new TGMS lines with good floral traits in rice

Two-line breeding in exploitation of thermo-sensitive genic male sterile system is pursued with the objective of development of hybrids with high heterotic potential. A total of 66 new TGMS lines were developed and screened under sterility favoring environment for tgms gene expression during summer and sterility limiting environment during winter at Paddy Breeding Station, Coimbatore for the past five years. Out of 66 TGMS lines, 15 lines showed stable performance and seven TGMS lines viz., COTGMS 02, COTGMS 07, COTGMS 10, COTGMS 11, COTGMS 12, COTGMS 13 and COTGMS 15 were completely pollen sterile throughout the summer period. These lines had wider sterility expression period with very good floral traits viz., higher pollen sterility per cent, panicle and stigma exsertion per cent, wider glume opening favorable for enhanced out-crossing rate and seed set percentage during seed production.