一,建立三级种子田,保持油葵良种优良种性翁牛特旗杜家地公社农科站1975年引进油用向日葵派列多维克(先进工作者),两年后混杂退化现象严重,出现植株高低不齐、成熟不一致、籽粒变色、皮壳增厚等现象。针对这个问题,他们利用派列多维克原种,建立了三级良种繁育程序,即原种繁殖田——良种繁殖田——生产用种繁殖田。原种繁殖田,是用少量的原种 First, the establishment of three seed fields, to maintain the good nature of oilseed varieties Wengniute Banner Dujia commune Agricultural Station In 1975 the introduction of sunflowers to send the column Duo Weike (advanced workers), two years after the serious degradation of mixed, Uneven emergence of plants, mature inconsistencies, discoloration of the seeds, the crust thickening and other phenomena. In response to this problem, they used the Paidultivik original to establish a three-level breeding program, that is, the original breeding field - the breeding seedling - the breeding seedling. The original breeding field, is a small amount of the original species