Studies on Heteroses of Pei‘ai 64S／Javanica Rice

Agronomic Waits and heteroses of javanica varieties and the indica/javanica hybrids in Changsha are reported. Javanica rice exhibits long panicles, big grains, less panicles per plant, a long growth duration and high plant height in Changsha. The hybrid of Pei'ai 64S/javanica possesses positive heterobeltiosis in culm height, panicle length, panicles per plant, spikelets per panicle, grains per panicle,yield per plant, theoretic yield per hectare and actual yield per hectare; performs negative heterobeltiosis in days to flower, seed setting rate and 1000-grain weight. There are significant linear regression relations between culm height of the hybrid and panicle length of its male parent, panicle length of the hybrid and that of its male parent, spikelets per panicle of the hybrid and spikelets per panicle and panicle length of its male parent, grains per panicle of the hybrid and spikelets per panicle of its male parent, 1000-grain weight of the hybrid and spikelets per panicle of its male parent, respectively. In general, significant differences at 1% level are seen in most traits except grains per panicle and theoretic yield per hectare between the indica/javanica hybrid and Pei'ai 64S/Teqin (CK). Compared with the check, the indica/javanica hybrids have positive standard heterosis in culm height, panicle length,spikelets per panicle, grains per panicle and 1000-grain weight but negative standard heterosis in days to flower, panicles per plant, seed setting rate, theoretic yield per hectare and actual yield per hectare. For the individuals, 11.1% hybrids possess > 40% standard heterosis in theoretic yield per hectare, 3.7% possess >40% standard heterosis in actual yield per hectare. The javanica restorer line 770 derives from a single cross of Pei'ai 64S/Moroberekan B-51-4-9-2. The hybrid 43S/770 possesses an elite plant type and strong heterosis.