小果白刺和泡果白刺的耐盐性

为比较不同种类白刺的耐盐性,通过蛭石盆栽和NaCl胁迫的方法,分析了小果白刺和泡果白刺的脯氨酸、可溶性糖含量,幼苗鲜重、干重及根冠比。结果表明:随NaCl浓度的增加,小果白刺的脯氨酸含量和可溶性糖含量持续稳定增加,显著高于对照,为对照的1.2～2.0倍;泡果白刺的两个指标均表现出急剧增加和急剧降低,在12%NaCl浓度时最高,分别为对照的2.9倍和2.2倍,显著高于对照,而在15%NaCl浓度下最低,为对照的59.7%和75.9%,显著低于对照。小果白刺幼苗地上和地下鲜重、地下干重及根冠比在低浓度NaCl胁迫下有显著增加,分别为对照的1.4、1.5、2.4和1.9倍,在高浓度NaCl下与对照无显著差异。NaCl胁迫使泡果白刺的幼苗鲜重、干重及根冠比显著降低。因此,各项指标均说明泡果白刺对盐胁迫更加敏感,耐盐性不及小果白刺。

Salt Tolerance of Nitraria sibirica Pall and Nitraria roborowskii Kom

In order to understand the salt tolerance of different species in Nitraria, the proline, soluble sugar, fresh and dry weight of seedlings and the root-shoot ratio of Nitraria sibirica Pall and Nitraria roborowskii Kom were analyzed by the treatment of NaCl stress in pots with vermiculite medium. The results show that the proline and soluble sugar of N. sibirica increased stably and continually and was 1.2 to 2.0 times compared with the control, but both of them in N. roborowskii increased firstly and reduced then, and appeared sharp change. Their highest vaules in N, sibirica under 12% NaCl concentration were 2.9 times and 2.2 times compared with the control, and the lowest in N. sibirica were 59.7% and 75.9%, which were significantly less than that of the control under 15% NaCl concentration. The overground and underground fresh weight, underground dry weight and root-shoot ratio of N. sibirica increased significantly in the low concentration of NaCl, reaching 1.4, 1.5, 2.4 and 1.9 times compared with the control, and were same as the control in the high concentration. The fresh weight and dry weight of seedlings and the root-shoot ratio of N. roborowsldi reduced significantly under NaCl stress. Therefore, all indexes suggested that N. roborowskii is more sensitive to the salt stress and the salt tolerance is lower than N. sibirica.