黄瓜子叶培养物花芽分化初期的生理变化

PHYSIOLOGICAL CHANGES AT EARLY STAGE OF FLORAL BUD DIFFERENTIATION IN CUCUMBER COTYLEDONS CULTURED in vitro

以黄瓜子叶离体培养物直接分化花芽为实验系统 ,研究了其在花芽分化初期的生理变化。结果表明 ,矿质元素含量变化比较复杂 ,培养 2 d时 Cu、Fe水平剧升 ,4 d时 Zn水平剧升 ,6 d时 Ca水平剧降 ;过氧化物酶 (POD)活性总体呈上升趋势 ,可溶性蛋白和核酸含量则呈下降趋势 ;内源多胺中腐胺 (Put)在培养 2 d时达峰值 ,精胺 (Spm)、亚精胺 (Spd)和尸胺 (Cad)则在培养 4 d时达峰值 ;内源激素中生长素 (IAA)和脱落酸 (ABA)在培养 2 d时剧降。

Some physiological changes occurring at early stage of floral bud differentiation in cucumber cotyledons cultured in vitro were studied.The results are as follows.The contents of mineral elements appeared to change variously,for example the contents of Cu and Fe greatly increased on the 2nd day of culture,Zn also increased on the 4th day,but Ca quickly decreased on the 6th day.The activity of peroxidase was increasing but the levels of soluble protein and nucleic acid were decreasing during the whole course of floral bud differentiation.On the 2nd day,the content of putrescine got to peak value;so did spermine,spermidine and cadaverine on the 4th day of culture.Compared with the other endogenous hormones,the rapid decreasing of IAA and ABA contents on the 2nd day was an important message.Based on these,we discussed the relationship between these physiological changes and the floral bud differentiation.