The sink structure character of super high-yielding ratooning rice

The sink structure characters of different yield potential of ratooning rice were investigated.The results indicated that the relationship between spikelet number per panicle and yield was the most closely in the first season,and the contribution to yield was the highest.In the ratooning season,the relationship between panicle number and yield was the most closely, and the contribution was the highest.Super high-yielding ratooning rice had larger sink.Not only in the first season but also ratooning season,the sink volume made greater contribution to yield than seed setting, as well as the contribution of total spikelets number per m2 to yield was higher than that of grain weight.The contribution of spikelet number per panicle to total spikelet number per m2 was higner than panicle number per area in the first season, and the ratooning season was contrary.It is necessary to foster larger panicle to enlarge sink volume for obtaining higher yield in the first season, as well as to foster much panicle number in the ratooning season.