铜麦6号苗期耐高铵与耐盐特性的鉴定及TaGS基因的表达模式分析

为鉴定小麦品种铜麦6号的耐高铵及耐盐特性，对铜麦6号、中国春及抗逆性较强的烟农19、三抗10号、矮优王、烟农21、山农25的发芽势和发芽率进行测定，发现铜麦6号的耐铵指数位列第一，耐盐指数位列第二。以中国春为对照品种，在高铵、高盐及其双重胁迫处理下，测定其苗期的叶片鲜重、根鲜重、主根和第一叶叶片长度以及根冠比，发现高铵、高盐及其双重胁迫处理7 d后，铜麦6号的上述指标均不同程度高于中国春(除铜麦6号的根冠比在高盐处理1 d后低于中国春外),说明铜麦6号具有较强的耐高铵和耐高盐特性。进一步采用qRT-PCR检测小麦苗期谷氨酰胺合成酶TaGS基因家族成员(根中TaGS1;1、TaGS1;2和TaGS1;3基因以及叶片中TaGS2基因)的表达模式，发现高铵、高盐及其双重处理均可诱导铜麦6号苗期TaGS基因上调表达，且高盐处理下上调表达更明显，其中除高铵与高盐双重处理7 d后的TaGS1;2基因以及高铵和高盐处理1 d后的TaGS2基因在铜麦6号中的表达量低于中国春外，其他三种处理不同时间点铜麦6号中这两个基因的相对表达量均不同程度高于中国春。这些结果说明，铜麦6号苗期TaGS基因家族与其耐高...

Identification of High Ammonium and Salt Tolerance of Tongmai 6 at Seedling Stage and Analysis of Expression Patterns of TaGS Genes

To identify the tolerance to high ammonium and salt of the wheat variety Tongmai 6, the germination rate and germination potential of Tongmai 6, Chinese Spring and strong stress resistance varieties(Yannong 19, Sankang 10, Aiyouwang, Yannong 21, Shannong 25) were measured. The results showed that the ammonium tolerance index of Tongmai 6 ranked first, and the salt tolerance index ranked second. Then, with Chinese Spring as the control, the fresh weight of leaves and roots, length of primary root and first leaf, and root-shoot ratio of Tongmai 6 at seedling stage were measured under the treatments of high ammonium, high salt, and their dual stresses. After 7 days of high ammonium, high salt, and their dual stresses treatments, the indices mentioned above of Tongmai 6 were higher than those of Chinese Spring by different degrees(except the root-shoot ratio of Tongmai 6 was lower than that of Chinese Spring after 1 day of high salt treatment), which indicated that Tongmai 6 had stronger tolerance to high ammonium and high salt treatments than Chinese Spring did. The relative expression patterns of TaGS1;1, TaGS1;2 and TaGS1;3 in root and TaGS2 in leaf, which belong to the TaGS family members of glutamine synthetase genes, were characterised by qRT-PCR. Results showed that high ammonium, high salt, and their dual treatments induced the up-regulated expression of the three TaGS genes in Tongmai 6 at seedling stage. Moreover, the up-regulated expression level was more significant when the seeding was under the high salt stress. Except the relative expression levels of TaGS1;2 gene after 7 days of dual treatments with high ammonium and high salt and TaGS2 gene after 1 day of high ammonium and high salt treatments, respectively, the relative expression levels of TaGS1;2 and TaGS2 of Tongmai 6 were higher than that of Chinese Spring by different degrees under the three treatments at all the time points. These results indicated that TaGS gene family of Tongmai 6 corresponded to its tolerance to high ammonium and high salt at seedling stage, among which TaGS1;2 and TaGS2 play the more important role at this stage.