低温对香蕉幼苗的伤害及外源H_2O_2、CaCl_2对香蕉抗寒性的影响

Low-temperature Injury of Banana Seedlings & Effects of Exogenous H_2O_2 and CaCl_2 on Cold Resistance in Banana

以香蕉品种‘巴西蕉’为材料,用H2O2、CaCl2、H2O(CK)喷洒香蕉幼苗植株,在人工气候箱中模拟低温胁迫,观察香蕉幼苗对低温的反应,研究外源H2O2、CaCl2对香蕉抗寒性的影响。结果表明,巴西蕉对低温敏感,且随着温度的降低,幼苗冷害症状加剧严重,膜透性加大,叶绿素降解加剧;和对照(CK)相比,低温胁迫下,外源H2O2、CaCl2能够提高7℃低温胁迫期间香蕉叶片脯氨酸含量和POD、CAT活性,降低MDA的积累。外源H2O2、CaCl2能有效降低香蕉幼苗叶片膜透性,减缓叶绿素的降解,减轻冷害程度,提高香蕉幼苗的抗寒性。

In this experiment,＇ Brazil ＇ banana,as the materials,were sprayed by H2O2,CaCl2 and H 2 O （CK） respectively.In the artificial climate box,the low temperature coercion was simulated in order to observe how banana seedlings reacted to low temperature.The effects of exogenous H2O2,CaCl2 on bananas cold resistance were studied.The results indicated that the ＇ Brazil ＇ tissue was sensitive to the low temperature and as the cold damage temperatures dropped,chilling injury symptoms of seedlings exacerbated,membrane permeability increased and the degradation of chlorophyll aggravated.As compared to CK,exogenous H2O2,CaCl2 could enhance the content of leaves ＇ proline and antioxidase overall activity,and reduce the accumulation of MDA during the period of 7℃ low temperature coercion.In the period of low temperature coercion,exogenous H2O2,CaCl2 effectively reduced the membrane permeability of banana seedling leaves,slowed down the decomposition of chlorophyll and alleviated the chilling injury level,and enhanced the cold resistance of banana seedlings.