低温弱光胁迫对甜瓜幼苗生长及生理指标的影响

以北方地区3个主栽甜瓜品种为材料,研究了低温弱光对甜瓜幼苗生长和生理指标的影响。结果表明,低温弱光胁迫下,甜瓜幼苗株高、茎粗、叶面积等形态指标迅速降低,分别比正常温光处理(CK)减少16.7%～20.0%、10.0%～13.5%和21.5%～20.2%,植株鲜质量和干质量分别比CK降低39.4%～51.7%和30.9%～45.1%,根冠比减少,幼苗的根系活力和叶绿素含量分别比对CK降低21.3%～42.4%和31.7%～41.5%,MDA含量明显上升。3个处理中,以低温弱光处理对甜瓜幼苗生长及生理指标影响最为明显。3个品种中,白兰瓜和黄河蜜的低温弱光耐性优于玉金香。

Effects of Chilling and Low Light on Vegetative and Physiological Parameters of Melon Seedlings

Using three melon cultivars widely cultivated in North China as materials,the effects of chilling and low light on vegetative and physiological parameters of melon seedlings were studied.The results showed that morphological parameters(plant height,stem diameter and leaf area) and growth degree(fresh weight and dry weight) of the seedlings descended under the stress of chilling and low light.Compared with CK treatment(the normal temperature and light conditions),plant height,stem diameter and leaf area respectively decreased 16.7%~20.0%,10.0%~13.5% and 21.5%~20.2%,and fresh weight and dry weight decreased 39.4%~51.7% and 30.9%~45.1%,respectively.The root cap ratio and root activity of the seedlings descended.Also,the stress affected the physiological parameters;chlorophyll content declined and malondi-aldehyde(MDA) content increased rapidly.Among the three treatments,chilling and low light(LL) gave the most significant effects on vegetative and physiological parameters of melon seedlings.As for the three cultivars,Bailangua and Huanghemi had stronger chilling and low light tolerance than that of Yujinxiang.