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油菜品种混杂退化的原因主要有四: 一是昆虫和风力等媒介传播使油菜品种产生生物学混杂。油菜是十字花科芸苔属,异交亲和性较强,无论品种间、类型间,以及与一些芸苔属近缘种间都能杂交。油菜开花期,在品种内因变化和外界环境条件的影响下,除了自身分离外,异株个体间,杂株与良种植株间,发生无休止反复杂交,使群体愈来愈复杂,新的杂合体与原品种不相符合的个体在群体中的比重日益逐渐增多,不符合要求的性状不断出现,使良种不
There are four main reasons for the ragweed hybrid degeneration: one is the biological mixture of rapeseed varieties caused by media transmission such as insects and wind. Brassica oleracea is a Brassicaceae family with strong heterosexuality and hybrids among varieties, between types and with some Brassica species. In the flowering stage of rapeseed, under the influence of the internal changes of varieties and the external environmental conditions, in addition to their own separation, there is an endless reciprocal hybridization among the individual plants, the hybrid plants and the elite plants, making the groups more and more complex. The new hybrids The proportion of individuals not in conformity with the original varieties is increasing gradually in the groups, and traits that do not meet the requirements continue to emerge, making the improved varieties not