结球生菜是菊科莴苣属一二年生草本植物，属高温感应性蔬菜。开花结籽期正值华北地区雨季，高温多雨严重影响授粉受精，造成华北地区采种困难。赤霉素作为一种植物生长调节剂，能促进长日照及低温感应性植物的花芽分化。这在白菜、胡萝卜、芹菜上已得到应用，但在结球生菜... Rope lettuce Compositae is a biennial lettuce herb, is a high temperature-sensitive vegetables. The flowering and seed-bearing period coincided with the rainy season in North China. The high temperature and rainy weather severely affected pollination and fertilization, causing difficulties in seed production in North China. As a plant growth regulator, gibberellin can promote flower bud differentiation of long-day and low temperature-sensitive plants. This has been applied in cabbage, carrots, celery, but in the knot lettuce ...