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1972—79年调查研究了上海农田杂草的发生和消长。在野外调查189种农田主要杂草自然发生情况,提出了四个发生型:以藜等为代表的早春发生型;以马唐、稗草等为代表的春、夏发生型;以看麦娘等为代表的秋、冬发生型;以小藜等为代表的春、秋发生型。同时,明确了在不同年份,不同茬口、不同耕作情况下,因环境条件的变化,杂草发生也有差异。掌握它们的发生规律和生长发育特点,为防除杂草及合理、适时应用除草剂提供了一定的理论依据。
1972-1979 surveyed Shanghai farmland weed occurrence and decline. In the field, we investigated the natural occurrence of major weed species in 189 kinds of farmland and proposed four occurrence types: the early spring type represented by Quinoa, the spring type and summer type represented by Crabgrass and barnyardgrass, As the representative of the autumn and winter occurrence type; to small quinoa as the representative of spring and autumn occurrence type. At the same time, it is clear that in different years, different stubble, under different tillage, due to changes in environmental conditions, weeds are also different. Grasp their occurrence and growth characteristics of growth and development, in order to control weeds and reasonable, timely application of herbicides provide a theoretical basis.