B_9即N—二甲胺基琥珀酰胺酸,是一种植物生长抑制剂。其在苹果及花生上的应用已有报道。笔者从1980—1982年进行了B_9浸种和不同时期叶面喷洒对小麦的生育影响及增产效果的研究,取得了肯定的结果。材料与方法试验在本所和李庄进行,设计分三部分,一是田间比较试验,试验地为沙壤土,中等肥力,随机排列,重复二次,行距27厘米,亩基本苗12万,小区面积8.64平方 B_9 N-dimethylamino succinamic acid, a plant growth inhibitor. Its application on apple and peanut has been reported. From 1980 to 1982, the author studied the effect of B_9 seed soaking and spraying foliar spray on the growth of wheat at different stages and obtained the affirmative results. Materials and Methods Experiments were carried out in the institute and Li Zhuang. The design was divided into three parts. The first was the field comparative experiment. The experiment was conducted on sandy loam soil with moderate fertility. The seeds were randomly arranged and repeated twice with a spacing of 27 cm. The basic seedling area was 120,000. 8.64 square