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通过对南充市小麦条锈病1999年以来共16年的发生流行情况研究,明确了小麦条锈病在本市的重发流行特点和趋势。即病害初见期越早,发生越重;其流行特点是在本地小麦条锈菌有两次传入侵染高峰期,第1次外来菌源大范围传入对病害流行起着关键作用,在田间存在1~3个流行高峰期,其中,第1个流行高峰期发生面积对当年病害流行起着决定作用,1月下旬的累计发生面积与年总发生面积成较高正相关,其相关系数为0.769 2;近16年,条锈病有13年在全市偏重至大发生,偏重至大发生频率达81.25%,比1995年以前,重发频率高50个以上百分点,轻发生只有2013年1年,仅占6.3%,说明条锈病已完全处于重发流行之态势。经对其成因探讨认为,导致本市近年小麦条锈病重发及流行的内因是品种抗条锈能力的降低或丧失,而造成小麦品种抗性丧失的直接原因是条锈菌新生理小种致病性强且已上升为主要小种,并继续保持为优势小种,暖冬和春季天气波动幅度大,雾、露日偏多直接造成了条锈病的大流行。
Based on the epidemiological study of wheat stripe rust in Nanchong City since 1999, the characteristics and trend of wheat stripe rust recurrence in the city were clarified. That is, the earlier the disease begins, the heavier it occurs. Its epidemic feature is that there are two peak times of invasive infection in the local wheat stripe rust, and the first large-scale introduction of the foreign bacterial source plays a key role in the epidemic of the disease. In the field, there are 1 to 3 epidemic peak periods. Among them, the occurrence area of the first peak of the epidemic period plays a decisive role in the prevalence of the disease in that year. The cumulative occurrence area in late January and the annual total occurrence area are positively correlated with higher incidence, The coefficient was 0.769 2; in the recent 16 years, stripe rust had been prevailed in the whole city for 13 years. The frequency of occurrence of stripe rust was 81.25%, higher than that of 1995 before recurrence frequency was higher than 50% Year, accounting for only 6.3%, indicating that stripe rust is completely in the trend of resumption of epidemic. The causes of the discussion that led to the city in recent years, the recurrence and epidemic of wheat stripe rust internal resistance is the ability to reduce or eliminate the stripe rust resistance, and the direct cause of the resistance of wheat cultivars caused by the new bacterium The disease has been strong and has risen to the main races, and continue to be the dominant races. The warm weather in the warm winter and spring has a large fluctuation range. The fog and the dew are the direct result of the stripe rust epidemic.