Effects of paclobutrazol treatment on the growth and flowering of Hyacinthus orientalis

Through foliar spraying of different concentrations of paclobutrazol solution,the effects of paclobutrazol on growth and flowering of Hyacinthus orientalis 'Blue Jacket' were studied.The results showed as follows: foliar-spraying of 100 mg/L of paclobutrazol solution was the best treatment.It decreased the growth rate,plant height and leaf area moderately.Compared to the control,the leaf thickness,flower diameter and weight of bulbs increased by 5.8%,2.8% and 5.3% respectively.At the same time,foliar-spraying of 100 mg/L of paclobutrazol solution significantly increased the chlorophyll content in leaves.It delayed the appearance of flower buds for 4 days,prolonged the florescence for 4 days,and put off the senescence of hyacinth.Foliar-spraying of 300 mg/L of paclobutrazol solution showed negative effects because of the high concentration.