盐分胁迫对桑树叶片中渗透调节物质含量的影响

Effect of Salt Stress on Contents of Osmotic Regulatory Substances in Mulberry Leaves

以农桑14号、昂绿1号、湖桑32号、鲁插1号4个桑树品种的2年生嫁接苗为试验材料,研究以不同浓度盐分胁迫不同时间后桑树叶片内渗透调节物质含量的变化。在盐分胁迫下,4个桑树品种叶片中的脯氨酸及可溶性糖和可溶性蛋白含量的变化呈现一定规律性,且品种间具有显著差异。4个桑树品种叶片中的脯氨酸含量在各种浓度盐分胁迫初期都迅速增加,但高浓度盐分胁迫后期叶片中的脯氨酸含量在品种间表现出显著差异;可溶性糖含量的变化在各种浓度盐分胁迫期间都表现出先升高后降低的趋势,但各个品种下降的时期不同;可溶性蛋白含量随盐分胁迫的持续不断降低,但湖桑32号和鲁插1号叶片中的可溶性蛋白含量在高浓度盐分胁迫后期略有升高。以上结果提示:在桑树对盐分胁迫的响应过程中,叶片中的渗透调节物质可能起到一定的调节作用,而不同品种间表现出的差异性可能与品种的抗盐能力有关。

In present study, two-year-old grafted mulberry saplings of 4 mulberry varieties namely Nongsang 12, Anglu1, Husang 32 and Lucha 1 were used to investigate the effect of different salt stress on the contents of osmotic regulatory substances in mulberry leaves. The results showed that, under different salt stresses, changes of proline, soluble sugar and soluble protein contents in leaves of the 4 mulberry varieties had certain regularity and showed significant differences between different varieties. In the early stage of various salt stresses, proline contents in mulberry leaves of all 4 varieties increased rapidly and maintained at a high level. But significant differences between different varieties were only observed at the late stage of high salt stress. The soluble sugar contents increased in early stage of the stress and declined in the late stage. But when to begin the decline was different across different varieties. The soluble protein contents declined along with the salt stress. However, the soluble protein contents in mulberry leaves of Husang 32 and Lucha 1 increased slightly in late stage of high salt stress, The above results indicate that, in response to salt stress, the osmotic regulatory substances in mulberry leaves have certain osmotic regulatory functions, and the response difference across the 4 varieties can be attributed to their varied tolerances to salt.