低温锻炼对白掌组培苗抗寒性的影响

【目的】分析低温锻炼对白掌组培苗生理生化指标的影响,为探索白掌抗寒性生理生化机制提供参考依据。【方法】测定低温锻炼前后白掌组培苗叶片抗氧化酶活性及可溶性蛋白质(SP)、游离脯氨酸(Pro)、可溶性糖(SS)和丙二醛(MDA)含量,对比分析白掌组培苗的抗寒性能。【结果】白掌组培苗经3℃低温锻炼后抗寒性明显增强,表现为低温处理72 h后叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)、抗坏血酸过氧化物酶(APX)和过氧化氢酶(CAT)活性分别提高43.0%、47.0%、33.0%和61.0%;叶片SP、Pro及SS等渗透调节物质含量分别增加了2.0倍、5.0倍和70.0%。同时,低温锻炼对白掌组培苗叶片细胞膜造成了一定程度的伤害,表现为MDA含量增加。脱锻炼1 d后抗氧化酶活性和SP、Pro及SS含量略有下降,但仍高于未经低温锻炼的组培苗。【结论】生产上可通过低温锻炼白掌组培苗来提高其抗寒性和移栽成活率。

Effects of cold hardening on cold resistance of Spathiphyllum floribundum tissue-cultured plantlets

Objective]In order to provide reference basis for study on physiological and biochemical mechanism relat-ed to cold resistance of Spathiphyllum floribundum,effects of cold harding on physiological and biochemical indexes of S. floribundum tissue-cultured plantlets were studied. Method]With S. floribundum tissue-cultured plantlets as materials, activities of antioxidant enzymes and contents of soluble protein(SP),proline(Pro),soluble carbohydrates(SS) and malon-aldehyde (MDA) were determined before and after cold harding, in order to analyze cold resistance of S. floribundum tissue-cultured plantlets. Result]Results showed that, activities of superoxide dismutase(SOD),peroxidase(POD),ascor-bic acid peroxidase(APX) and catalase(CAT) in tissue-cultured plantlets increased by 43.0%,47.0%,33.0% and 61.0%after cold hardening(3 ℃) of 72 h,respectively,resulting in improvement of cold resistance of tissue-cultured plantlets. Furthermore, contents of osmotic regulators viz., SP, Pro and SS in leaf increased by 2.0,5.0 times and 70.0%, respec-tively. Meanwhile,cold hardening increased MDA content, resulting in damage of leaf cytomembrane of tissue-cultured plantlets. Activities of antioxidant enzymes and contents of SP, Pro and SS all declined slightly after deacclimation for 1 d, but were higher than those of tissue-cultured plantlet that did not suffered from cold harding. Conclusion]Cold resistance and transplanting survival rate of S. floribundum tissue-cultured plantlets can be improved by cold harding in actual pro-duction.