The length proportion of basal internode to upper 5 internodes should be 1: (1.5-2): 2.5: 3: (4.5-5): (7-8) respectively.

• 2.；3 上层根数：上层根数5-6条/茎，单茎上层根数与单穗重、千粒重呈显著扬州大学硕士学位论文正相关关系。