Heterotic expression of two line hybrids in rice

摘要

Extent of heterosis was explored in 4 thermo-sensitive genie male sterile (TGMS) lines and 22 non-TGMS testers by making 88 crosses. The magnitude of relative heterosis, heterobeltiosis and standard heterosis with checks (CORH 2 and ADTRH 1) were estimated. The hybrids, GD 98029 x IR 61608-213, GD 98049 x IR 61608-213 and GD 98014 x RR 166-645 could be exploited for earliness as they exhibited negative and significant standard heterosis for days to 50 percent flowering over the checks. Top yielding hybrids viz., GD 98049 x IR 63875-196-2-2-1-3, GD 98014 x TKM11, GD 98049 x TKM11, GD 99017 x TKM12 exhibited significant standard heterosis over CORH 2 and ADTRH 1. Most of the high yielding hybrids manifested significant positive heterosis for yield contributing characters viz., more number ofproductive tillers plant~(-1), long panicles, more number of filled grains panicle~(-1), spikelet fertility and 1000 grain weight. Hence, these hybrids may be usedfor commercial cultivation in two line hybrid rice.