12℃低温锻炼对棉苗抗冷性的影响

Effect of 12 ℃ Low Temperature Exercise on Cold Resistance of Cotton Seedlings

棉花苗期的抗冷性直接影响棉花生产,抗冷性是棉花育种的一项重要指标。通过棉苗抗氧化酶活性和可溶性蛋白含量的变化来分析12℃低温锻炼棉苗后,其耐4℃冷胁迫能力。将棉种脱绒后浸泡适当时间,于28℃/12 h光照条件下培养至长出至少2片真叶后,分为2组:一组作为对照(未低温锻炼),另一组于12℃/12 h光照条件下低温锻炼5 d,然后2组一起于4℃/12 h光照条件下冷胁迫5 d后,取真叶进行研究。结果表明,晋棉35号、晋棉44号、晋棉49号这3种供试棉种经过12℃锻炼5 d后,在4℃冷胁迫过程中基本都表现出SOD,CAT,POD活性以及可溶性蛋白含量明显高于同期未经低温锻炼的棉苗,说明经过12℃临界低温锻炼5 d后的棉苗耐4℃冷胁迫能力有所提高。

Cold resistance on stage of cotton seedling is directly related to production and it is also an important indicator of the cotton breeding. This study detected the change of antioxidant enzyme activity and the content of soluble protein of cotton seedlings,under the condition of cold resistance at 4 ℃ after cold acclimating at 12 ℃. Detinted cotton seeds and soaked for an appropriate time, then cultured at 28 ℃/12 h, until it grew at least two true leaves. Leaving the control（without cold acclimating）, the remain were created at12 ℃/12 h acclimating for 5 days. Then all placed at 4 ℃/12 h cold stressing for 5 days, then determinated the indicators of euphylla.The results showed that after exercising at 12 ℃ for 5 days, in the 4 ℃ cold stress process, Jinmian 35, Jinmian 44, Jinmian 49 all showed SOD, CAT, POD activity obviously higher than that of without exercising, and the soluble protein content also showed obviously higher than that of the control. It indicated that cold resistance of cotton seedlings at 4 ℃ improved after at 12 ℃ critical cold acclimating for 5 days.