甜菜种株生育规律的研究

A Study on Growth Regularity of Beet Mother Tree

甜菜种株生育期为112天，需积温2165．4℃。种株形成10个左右一级枝，140个以上二级枝，110多个三级技，20个左右四级技，基生叶40余片，苔叶260余片，乳熟期达最大叶面积指数3．8。二、三级枝种子产量之和占全株的89．9％。盛花期至乳熟期干物质生产速度最快18．65g／d，干物质分配中心的顺序为：基生叶→苔叶→果枝→种球。种株生产期间母根增重12．6～41．8％，糖分降低57％左右，老母根尚存7～8个糖度。

The total growth period of beet mother tree is 112 days, and theaccumulating temperature isn' t less than 2165.4℃. During milk ripe stage,beet mother tree reaches its maximum leaf area index(3.8). The second,the third branch amount to 89.9 per cent of the mother tree seed yield.From full bloom stage to milk ripe stage, the synthetic speed of driedsubstance is the most fast (18.65g/d).