Regulation of Growth Patterns in Rice by Cultural Practices

It could increase the separation degree from tillering termination to panicle initiation by transplanting young seedlings with thick space or adopting a nitrogen application system that was able to prolong the vegetative growth period of rice.On the other hand, the separation degree from tillering termination to panicle initiation could be lessened and the overlaping degree enhanced if old seedlings were transplanted, and wide space adopted; or less nitrogen applied in the early growth stage on the main field. The tillering-panicle initiation-overlapping pattem happened usually to the early maturing varieties and the tillering-panicle initiation isolation types could often be seen in the middle or late maturing varieties. Growth pattem of the later-season varieties which strongly sensitive to photoperiod was more easily regulated by the different seedling ages than that of the earlier-season varieties which insensitive to photorerioa.