通过对大白菜栽培改良过程中，３种留打药行方式所造成的边行效应及其对群体产量影响的试验研究证明，由于留空行后增加了边行植株的光合速率与蒸腾速率，边行与行内温、湿度环境条件亦有较大差异；边行的软腐病、黑腐病、霜霉病的发病率和病情指数均比行内为低，对黑斑病的影响不大；边行的平均单株荒菜重较中间行高１６％～１９％，净菜重高１４％～１７％，差异达极显著，但中间各行差异均不显著。通过试验还证明，普通留打药行的方法，虽然确实可以增加边行效应，但仍不能弥补因减少株数而造成群体产量的损失。为此提出了改进留行方式，扩大边行效应的优势，降低栽植密度，减少病虫危害，提高单株重量，从而保证群体产量的具体措施。 Through the improvement of Chinese cabbage cultivation, the effects of side-rowing caused by the three types of drug-recycling lines and their effects on the population yield have been proved by experiments that the photosynthetic rate and transpiration rate of side-rowed plants increased after blank rows. The environmental conditions of temperature and humidity in line and line are also greatly different. The incidences of soft rot, black rot and downy mildew in line side and disease index are lower than those in line, and have little effect on black spot. The average weight per plant of row plants was 16% -19% higher than that of middle row, and the net weight of vegetables was 14% -17%. The difference was extremely significant, but the difference among rows was not significant. The experiment also proves that the method of ordinary dunghuankao can indeed increase the sideline effect but still can not make up for the loss of population yield caused by reducing the number of plants. Therefore, some concrete measures are put forward, such as improving the way of stay, expanding the advantage of borderline effect, reducing planting density, reducing pests and diseases, raising single plant weight and ensuring group output.