油菜即将成熟了,为了夺取明年更大丰收,要抓紧做好选留种工作。毛主席教导我们:“有了优良品种,即不增加劳动力、肥料,也可获得较多的收成。”广大贫下中农在生产实践中深有体会地说:“种子年年选,产量节节高”,关键问题在于“年年选”。品种特性随着栽培管理条件的变化而发生变异退化,这在油菜生产过程中是经常遇到的。一个良种栽培几年后。往往出现成熟期不一致,株型不整齐,茎杆有青、紫色的分离,抗病性逐年减弱,甚至在甘 Rape is about to mature, in order to seize a greater harvest next year, we must pay close attention to doing well to choose to stay kind of work. Chairman Mao taught us: “With excellent varieties, that is, without increasing labor force and fertilizer, more crops can be obtained.” The majority of poor peasants and middle peasants said in their production practice: “The seeds are elected by the year and production is steadily rising. ”The key question is“ Yearly election. ” Variety characteristics with the change of cultivation and management conditions change mutation degeneration, which is often encountered in rapeseed production process. A few years after cultivation of a good species. Often there is inconsistent maturity, plant type irregular, stalk green, purple separation, disease resistance weakened year by year, even in the sweet