EFFECT OF PACLOBUTRAZOL (PP333) ON DIRECT FLORAL BUD FORMATION OF THE DECAPITATED CUCUMBER SEEDLINGS UNDER POOR NUTRITION
Pang Ji-liang Sun Jian-hong Liang Hai-man (Hangzhou Agricultural Science Institute, Hangzhou 310008 Department of Biology, Hangzhou University, Hangzhou 310012)
The effects of KNO3 and paclobutra-zol (PP333) on direct floral bud formation at the cotyledonary node region of the decapitated cucumber seedlings cultured with nutrient solution of low strength have been studied. Direct formation of the floral buds was found to be closely correlated with KNO3 level. When nutrient solution was supplemented with 0.01 mmol/L KNO3, the higher percentage of direct floral bud formation i. e. 38.33% was got. Effect of PP333 on direct floral bud formation was more significant, and the higher percentage i. e. 73.33% was got when nutrient solution was supplemented with 0.75mg/L PP 333. The foliar sprays of 500 ppm PP 333 stimulated floral bud formation not as effectively as supplement of PP 333 to nutrient solution, the percentage of direct floral bud formation was 45% only. The results suggest that this experimental system would be valuable in studying the mechanism of floral evocation and development.