小麦单基因系TcLr19抗叶锈防卫反应的表达与叶锈菌侵染进程关系的初步研究

Relationship between the Activity Changes of Defense Enzymes of Wheat Near Isogenic Line TcLr19 and the Infection Process of Puccinia triticina

试验采用小麦单基因系TcLr19,感病对照Thacher(Tc)及叶锈菌小种366和165,利用组织化学方法,对接种后不同时间点叶锈菌在亲和和不亲和寄主上的发育情况进行观察,并对表现不同侵染型的TcLr19-叶锈菌组合中的2种防御酶苯丙氨酸解氨酶(PAL)和过氧化物酶(PO)的活性变化及发生过敏性死亡(HR)的细胞面积进行测定。结果表明,伴随着叶锈菌的侵染,TcLr19接种叶锈菌小种366(侵染型为0;)后PAL的活性分别在24,72 h出现高峰,PO活性在48 h达到最高峰,发生HR的细胞面积从接种后24 h逐渐增加直至96 h达到高峰;而接种叶锈菌小种165(侵染型为1)后2种酶活性变化及HR的变化和接种366具有相同趋势,但是前者的酶活性峰值低于后者,且发生HR的面积在96 h之前一直也小于后者。小麦对叶锈菌的抗性表达程度与防卫反应的表达强度呈正相关关系。

The resistance gene was activated after the wheat was infected by Puccinia triticina,and the metabolism activity of related resistant materials was strengthened then.This article was aimed to reveal the relationship between the activity changes of defense enzymes of wheat near isogenic line（NIL）TcLr19 and the infection process of Puccinia triticina.The infection processes on wheat NIL TcLr19 of the leaf rust race 366 and 165 were observed by fluorescent staining.According to that result,the activity changes of PAL and PO were determined when the TcLr19 was inoculated with 366（infection type was 0;） and 165（infection type was 1）at different times.The results showed that there were two activity peaks of the PAL in TcLr19 at 24 h and 72 h after inoculated by leaf rust race 366,and the PO activity peak appeared at 48 h.During this time,cell area undergoing HR was raising from 24 hpi until 96 hpi.While,there was a same tendency on the combination of 165 and TcLr19.But all of the numbers were lower than the other combination.The resistance of wheat to leaf rust fungus was positively correlative with the expression strengthen of defence reaction.