将我国小麦秆锈菌优势小种21C3分别与历年来出现频率很低的34C1或116小种的夏孢子等量混合,在不同温度条件下,转接于八个来自次要越冬区长江中下游感病的生产品种上。经几个夏孢子世代的继代转接结果表明:21C3小种的毒力虽弱但与34C2或116种相比,其相对生存能力强;而34C2和116小种的毒力虽强,但相对生存能力却弱。小种间毒力强弱与其生存能力强弱呈负相关的现象,可能是我国小麦秆锈菌21C3小种在相当长的时期处于优势的原因之一。在一定高温条件下,虽能影响小种频率上升或下降的速度,但未能左右其总的趋势。试验应用的继代品种对不同小种的感病性没有显著差别。 21C3, the dominant race of wheat stripe rust, was mixed with the same amount of summer spores of 34C1 or 116 seedlings which had a very low frequency over the years respectively. Under different temperature conditions, they were transferred to eight middle and lower reaches of the Yangtze River Sick on the production of varieties. The succession transfer results of several summer spore generations indicated that the 21C3 races had weaker virulence but higher relative survival ability than 34C2 or 116. However, the virulence of 34C2 and 116 races was strong, Relative survival is weak. The interspecific virulence of the interspecific hybrids was negatively correlated with their viability. It may be one of the reasons why the races of S.cereticolata 21C3 were dominant in a relatively long period of time. Under certain high temperature conditions, although it can affect the speed of racial frequency rise or fall, but failed to control its overall trend. There was no significant difference in the susceptibility of different races to the subculture tested.