激动素对菊花花瓣衰老生理的影响

Influence of kinetin on senescence physiology in petals of chrysanthemum

【目的】探究激动素(KT)对菊花花瓣生理活动的影响,为延缓菊花花瓣(舌状花)衰老、提高观赏价值提供参考依据。【方法】在秋菊"圣光华宝"品种从定头到花蕾出现期,以10、20、40 mg/L的KT溶液进行全株喷雾处理,测定菊花花瓣中可溶性糖与可溶性蛋白含量、超氧化物歧化酶(SOD)活力、超氧阴离子自由基()产生速率、丙二醛(MDA)含量和花瓣浸出液相对电导率(REC)等生理生化指标。【结果】10和20 mg/L KT处理提高了菊花花期花瓣中可溶性糖、可溶性蛋白含量及SOD活力,降低了产生速率、MDA含量和花瓣浸出液REC。其中,20 mg/L KT处理花瓣中的可溶性糖含量和SOD活力在开花第21 d比对照(喷蒸馏水)分别增加37.1%和31.5%,产生速率、MDA含量在开花第6 d比对照分别降低32.4%和38.5%,均达极显著差异水平;可溶性蛋白含量在开花第21 d比对照增加25.3%,花瓣浸出液REC在开花第16 d比对照降低33.1%,均达显著差异水平。【结论】适宜的KT处理对延缓菊花"圣光华宝"品种花瓣细胞衰老起积极作用,且以20 mg/L KT的处理效果较佳。

[Objective]The present experiment was conducted to study the effects of kinetin （KT） on senescence physi- ology in petals of chrysanthemum to provide references for delaying the senescence of petals and improving the ornamental value of chrysanthemum. [Method]Chrysanthemum ＂Shengguanghuabao＂ varieties were sprayed from phase fixed-head to the flower buds appearance with the aqueous solution under different concentrations （10, 20, 40 mg/L） of KT. Some physio- logical and biochemical indices were measured in petals of chrysanthemum during florescence, such as the content of soluble sugar, soluble protein, the activity of SOD, the O2^- production rate, MDA content and the relative electrical conductivity of petals exudates. [Result]In the aqueous solution of 10 and 20 mg/L, KT enhanced the content of soluble sugar, soluble pro- tein and the activity of SOD and decreased O2^- production rate, MDA content and relative electrical conductivity of petals exudates. Especially in the aqueous solution of 20 mg/L, the soluble sugar content and the activity of SOD increased by 37.1% and 31.5% compared with the control on the 21^st day. O2^- production rate and MDA content were reduced by 32.4% and 38.5% on the 6^th day. All these four indices had extremely significant difference. The content of soluble protein increased by 25.3% compared with the control on the 21^st day. The relative electrical conductivity of petals exudates was reduced by 33.1% on the 16z day. Both of them reached significance difference. [Conclusion]KT can delay the senescence of floral organ. The 20 mg/L KT treatment play an active role in delaying the cellular senescence of petals.