Effects of Different Concentrations of Paclobutrazol on Growth of Cucumber Seedlings

In the paper,we studied the effects of different concentrations of 15% paclobutrazol powder(PP333) on the growth of Taiwan small cucumber seedlings.The results showed that,PP333 could significantly improve the sound seedling index and the stem diameter of cucumber seedlings,reduce the plant height and slow down the growth speed of the cucumber seedlings.And the higher the concentration,the more obvious the effects.When the concentration of PP333 reached to 0.1%,runt seedlings and the phytotoxicity on the cucumber seedlings would appear,but lower concentration of PP333 would not affect the normal growth of cucumber.In order to control the excessive growth of cucumber seedlings,we gave suggestion on evenly spraying 0.05% PP333 once on cucumber leaves after the expansion of the first true leaf with a small amount.