The stage from jointing to booting is long and the differentiation of youngear is abundant.
拔节孕穗期长，幼穗分化充分，有利于壮秆大穗的形成。
2
Through the study of 1200 flowers of 400 youngear of 49 combinations, a concrete index judging the period of the pollen development according to the shape of plant and flowers was put forward;