大麦幼苗多胺合成比脯氨酸合成对盐胁迫更敏感  

The Biosynthesis of Polyamines Is More Sensitive Than That of Proline to Salt Stress in Barley Seedlings

作　　者：赵福庚[1] 刘友良[1] 

机构地区：[1]南京农业大学农学系,南京210095

出　　处：《植物生理学报（0257-4829)》2000年第4期343-349,共7页Acta Phytophysiologica Sinica

基　　金：海洋八六三!(8190806)基金资助项目

摘　　要：NaCl 2 0 0mmol/L处理结合14 C Glu叶面饲喂 6天龄大麦幼苗 ,结果证明盐胁迫下Pro主要积累在叶片中 ,在根系中PA的积累占优势。PA合成途径对盐胁迫的响应早于Pro。盐处理 8h以后PA与Pro的合成竞争共同前体Arg。盐胁迫激活了Pro两条合成途径 ,胁迫 8h以前Pro积累主要受Glu途径控制 ,随后Orn途径对Pro积累的贡献占主导地位。盐胁迫促进了PA合成的Arg途径 。Six day old barley( Hordeum vulgare L.) seedlings were put under salt stress by treating with NaCl 200 mmol/L and then L 14 C]glu[CM(183/4]tamate was spread on leaves, and the destiny of 14 C in leaves other than the glutamate fed ones and roots of the seedlings was traced. The results showed that proline accumulated mainly in leaves while polyamines accumulated predominantly in roots under NaCl stress (Fig.2). The time courses of the changes in the levels of polyamines and proline demonstrated that the response of polyamine pathway to salt stress was earlier than that of the proline pathway to salt stress (Fig.2). The biosynthesis of polyamines and proline were [HJ6:2]competing for arginine as a precursor 8 h after the starting of treatment (Figs.3,4). Both glutamate and ornithine pathways of proline biosynthesis were stimulated by salt stress and within 8 h of treatment the proline increase was due mainly to the glutamate pathway, but after that the contribution of the ornithine pathway predominated (Fig.5). The arginine pathway of polyamine formation was stimulated by salt stress, whereas the ornithine pathway was uneffected (Fig.6).

关 键 词：多胺 脯氨酸 生物合成 盐胁迫 大麦幼苗 

分 类 号：Q945[生物学—植物学]