NaCl预处理提高两种铁线子属果树耐寒性的研究

NaCl pretreatments improving cold tolerance of two Manilkara species

古巴牛乳树和人心果是铁线子属具有开发前景的热带珍稀果树。为了将这两种果树在亚热带地区推广种植,该研究在已知这两种果树具有较高耐盐性的研究基础上,采用盆栽试验法,对3年生幼苗设置10‰、20‰的Na Cl预处理,一定时间后依次进行9℃、3℃的低温胁迫,分析比较其叶片中多种渗透调节物质含量及抗氧化酶活性的变化。结果表明:两种果树叶片渗透调节物质含量及抗氧化酶活性的变化趋势是一致的。在9℃、3℃的低温胁迫下,10‰、20‰Na Cl预处理叶片中的游离脯氨酸、可溶性糖和可溶性蛋白质含量及超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性均明显高于对照组,同一低温条件下,耐寒性强弱依次为10‰>20‰>对照(CK)。因此推断Na Cl预处理可以有效提高铁线子属果树的耐寒性,其中以10‰预处理最为理想,此时古巴牛乳树和人心果的实际盆土盐度分别为2.46‰、1.14‰。

Manilkara roxburghiana and M.zapota are precious tropical fruit trees with good development prospect.Based on the results that they had higher salt tolerance,three-year seedlings were treated under 9 ℃ and 3 ℃ cold stress after 10‰and 20‰ Na Cl pretreatment,and the changes of osmoregulation substance contentments and antioxidant enzyme activities were studied.The results showed that changing tendency was the same between the two species.The contentments of proline,soluble sugar,soluble protein and the activities of SOD,POD and CAT in the groups under 10‰ and 20‰ Na Cl pretreatments were higher than those in the contrast.The capacities of cold tolerance were as followed： 10‰ 20‰ CK.It was deduced that Na Cl pretreatments might effectively improve the cold tolerance of the two species.10‰ Na Cl pretreatment was most effective when the soil salinity of M.roxburghiana and M.zapota were 2.46‰ and 1.14‰ respectively.The results provided the theory direction and technology support for spread growth of the two species.