阿坝州小麦条锈病发生规律的研究

1979—1985年在四川省阿坝州越夏区进行条锈病发生规律调查。该地区海拔2900米以上的晚熟小麦约2.5万亩,条锈病持续发生至9月下旬,为自生麦苗和部分早播秋苗提供菌源。自生麦苗的发病面积近3万亩,其中休闲地约2.5万亩,主要分布在松潘、黑水2400—2900米地区,自生麦苗较多,发病较重;荞麦复种地约4000亩,主要分布在黑水、茂汶和汶川等地1700—2500米地带,自生麦苗较少,发病较轻。自生麦苗提供菌源的关键时期是9月上旬至10月下旬。秋苗发病面积约3.7万亩,主要分布在松潘、黑水2700—2950米地带,自9月中旬至12月下旬不断发生流行,而以8月中旬至9月中旬播种的秋苗发病较重,菌源较多,这在越夏菌源传播中起着很重要的作用。条锈菌在阿坝州又可越冬,构成周年侵染循环,常年流行,这不仅严重危害当地小麦生产,而且向广大冬麦区秋苗提供大量菌源。因此,综合治理阿坝州越夏区至关重要。

STUDIES ON THE EPIDEMIOLOGY OF WHEAT STRIPE RUST(PUCCINIA STRIIFORMIS WEST.) IN ABAZHOU,SICHUAN PROVINCE

Abazhou of Sichuan Province, where stripe. rust of wheat caused by Puccinia Striiformis often severely damages the wheat, is one of important oversummering districts of wheat stripe rust in China. The pathogen oversummers on late winter and spring wheat and volunteer wheat. The lowest altitude of oversummering is about 1700m. Field surveys and observations on the epidemiology of this disease were carried out during 1979-1985. The results indicated that the stripe rust in this region occured above altitude 2900m and lasted up to late September it spread to volunteer wheat and autumn seedlings of early sowing winter wheat. The area of diseased volunteer wheat was about 2000 hectare, including fallow fields and regions of resowing buckwheat. In the former areas, about 1666.7 hec., there were more volunteer wheat plants and stripe rust was more serious. It chiefly distributed in two wheat growing region, Songpan county and Heishui county at the altitude 2400-2900m. The latter area, about 266.7 hec., Chiefly included three wheat growing regions, Heishui county, Maowen Qiang autonomous county and Wenchuan county, at the altitude 1700-2500m, There were less volunteer wheat plants in this area and the stripe rust was not serious. The time of occurrence of stripe rust on volunteer wheat was the late October, a critical time for spread of pathogen. The acreage of diseased autumn seedlings of winter wheat was about 2466.67 hec., It was chiefly distributing in two wheat regions of altitude 2700-2950m, Songpan county and Heishui county. The time of occurrence of autumn seedlings stripe rust was from mean Sep. to late Dec., but autumn seedlings sowed in mean Aug. to mean Sep. were serious on stripe rust. A great amount of infective sources may be offered from this area to winter wheat growing areas. Therefore, early sowing autumn seedlings play very important role in the spread of the pathogen.The stripe rust may overwinter in Abazhou. Altitude of overwintering was about 2800m, and the amoun of overwintering pathogen was increased with altitude falling down. Thus, stripe rust in Abazhou could oversummer and also could overwinter. It forms infection all around the year. More importantly, it not only damage wheat in locals but also offer pathogen to vast winter wheat area. So the integrated control of the oversummering field in Abazhou is very important. It will include resistant variety breeding and introduction, eradicat volunteer wheat, Bayleton seed treatment, fit sowing time, etc.