西瓜蔓叶生长过旺会造成生长中心转移,营养过分集中到蔓叶生长方面,表现在植株上被称为徒长,又叫跑蔓、疯长、旺长等。西瓜徒长后,一般表现为瓜蔓变粗变脆,节间变长;叶柄细而长,叶片薄而狭长,叶色淡,雌花出现延迟,不易坐瓜;雌花开放时,瓜梗细而短,子房纤小,易萎缩化瓜。生产中一般采用下列措施控制西瓜徒长。 1.控制水分和氮肥 肥水施用过量,特别是氮肥过量,磷、钾肥不足时,很容易使植株徒长。肥水使用时期掌握不当,也易造成徒长。例如在坐瓜前肥水过大,营养集中供应蔓叶生长,生长中心不能及时由营养生长转移到生殖生长, Growth of watermelon vine leaves will cause excessive growth of the transfer center, excessive concentration of nutrients to the growth of the vine leaves, manifested in the plant is leggy, also known as ran Man, soaring, so long. Watermelon is a long, the general performance of the melon become coarse and brittle, internodes become longer; petiole thin and long, thin and long leaves, leaf color pale, female flowers appear delayed, easy to sit melon; , Ovary small, easy to shrink melon. Production generally use the following measures to control watermelon leggy. 1. Control of water and nitrogen fertilizers over-use, especially over-nitrogen, phosphorus, potash inadequate, it is easy to make the plant leggy. Improper use of fertilizer and water, but also easy to cause leggy. For example, in the water before the melon is too large, concentrated supply of dried cranberry leaf growth, the growth center can not be transferred from vegetative growth to reproductive growth,