在大白菜(Brassica pekinensis Rupr.)的采种上,一直存在着“大株留种”与“小株留种”的问题。所谓“大株留种”(亦称母株留种),就是把秋冬间采收的叶球,贮藏过冬,到第二年春暖后,移到田间,开花结籽。所谓“小株留种”,就是在初冬(江南一带),或早春(华北一带)播种。到4—6月间开花、结籽。大株留种经过叶球的选择,可以保持品种的优良特性。但是要大量采用大株留种,成本高,而且母株越冬,常带有病菌,容易发生病害,采种量因而有时反比小株留 There is always the problem of “large-plant species retention” and “small-species species retention” on Chinese cabbage (Brassica pekinensis Rupr.). The so-called “large plant stay species” (also known as the parent plant species), is to harvest autumn and winter leaves of the ball, stored in winter, to the spring after the second year, moved to the field, flowering and seed. The so-called “small-leaved species” is in the early winter (Jiangnan area), or early spring (North China area) sowing. From April to June flowering, seed. Large strains of leaves after the choice of leaves, you can maintain the excellent characteristics of varieties. However, a large number of large-scale species should be used to keep the species and the cost is high. However, the mother plants are overwintering, often with pathogens, and are prone to diseases. Therefore,