The Effect Of Low Temperature And Wheat Cultivar Winterhardiness On Overwintering Of Puccinia Striiformis F. SP. Tritici

Overwintering of Puccinia striiformis f. sp. tritic (PST) is one of the key factorsaffecting the rust epidemic. We studied the effect of low temperature and wheat cultivarwinter hardiness on overwintering of PST using real-time PCR on the RNA level, andobtained the following results:(1) Using the chill and reviving method, the difference of freezing resistance of varietiesbetween Xiaoyan22, Xinong979and Jingnong411were analyzed. It was indicated that underlow-temperatue disposal of36h, the half lethal temperature of Xiaoyan22, Xinong979andJingnong411are-6.5℃,-8.3℃and-11.8℃respectively. And so the most strongest freezingresistance was Jingnong411, followed by Xinong979, the weakest is Xiaoyan22.(2) Established a Real-time quantitative PCR standard curve of PST at the RNA level,and used this system to detect the influence of low-temperature and freezing resistance ofvarieties to PST overwintering. The results showed that: When the temperature is under0℃and-5℃, the survival rate of PST increased with the growing of winterness of wheat varieties.When the temperature is-10℃or below-10℃, there were no significant differences betweenthe two.(3) By sampling in Gansu and Qinghai province, and proceeding transplanting,observation and Real-time quantitative PCR quantitative detection, studied the overwinteringsituation of PST and the influence to survival rate of PST from low-temperature and freezingresistance of variety in fields. The results showed that PST can overwinter successfully inTianshui Qinzhou (Altitude:1587-1725m) and Pingliang zhuanglang, Gansu province(Altitude:1543-1666m) and Jianzhan, Gansu province (Altitude:2056m) during2012to2013. Besides the overwintering of PST was increased by increasing of the freezingresistance of varieties and the temperature changes range in fields.