1951~1983年我国小麦品种抗条诱性变异分析

本项试验反应了解放以来我国小麦品种抗条锈性变异的过程。变异情况有:<1>抗条锈性丧失较快:一般3～5年即丧失了抗性,如碧蚂1号、阿勃、丰产3号等;<2>抗条锈性丧失较慢:保持抗性10年以上,如繁6、阿夫等;<3>抗条锈性“失而复得”又“得而复失”:如南大2419;<4>抗条锈性不稳定:如平原50。变异特点为:易变区及其毗邻地区较早发生变异并自西向东发展,华北麦区要比西北、西南晚3年左右。小种的改变是历次抗条锈性变异的主要原因。小麦品种的大规模更替对条锈菌生理小种类型组成有巨大影响。大区间品种布局不同能导致小种分布的区域性差异。

THE ANALYSIS OF THE RESISTANCE OF VARIETIES IN THE WHEAT STRIPE RUST NURSERIES ON 1951-1983

The Chinese national uniform wheat stripe rust nuseries had been set up since 1951 for 27 years. 11 to 40 stations were selected according to the ecological characteristics and the severity of rust epedemic in previous years. The nurseries contends of cultivars widely used and a numbers of differentials used to identify races.It had been shown that the change of resistance of the varieties may be classified into the following categories:1. The loss of resistance by 3-5 years. A great numbers of cultivars are including in this group such as the Biona 1, Nungte 183, Beijing 8, Orofen, Fengcha 3, Taishang 1 et al. 2. The loss of resistance begin at least after 10 yrs. The group including an 6 and Funo. 3. Some cultivars such as Mentana changed from resistant to susceptible and after a number of years, it gained its resistance again and then lost the resistance again as the time going on. 4. The resistance tends unstable such as the cultivar Pinyoun 50, this cultivar showed to be resistant at many stations while in some other stations it appeared to be susceptible.The phenomenon of the change was analysed, in general, new race appeared to play a major part, while other factor such as certain environmental conditions and unstability of the cultivars constituted also important parts for certain cultivars.From the data, it exhibits clearly the following tendency:1. The change of the resistance were started in the northwest regions of China and then developed to the east part of Chinese plain, the cultivars in the later region changed about 3 years later. Race change was the cause in this case. 2. Change of the cultivars growing in the areas have great influence on the development of races. 3.Difference of the cultivars growing in different regions affected the race distribution in various regions of China.