我们在良种繁殖工作中,多年来遇到最易发生、最难解决的技术问题就是良种的混杂。为此,我们在1973～1974年,首先对“两杂”部分亲本繁殖的农艺程序进行了研究和探索,1975年又对全场六大作物计十二个品种(品系)全面开展了防杂保纯的“三圃”建设。到1978年基本解决了良种混杂这个老大难问题。当年全场原种繁殖面积1839亩,占总耕地面积的84.7%,占良种繁殖总面积的93%。上交国家良种43万斤,占粮食总产量的90%,其中原种为40万斤,占上交良种总数的93%。现将这段原种繁育的 We are in the breeding breeding work, the most prone to happen over the years, the most difficult to solve the technical problem is the thoroughbred mix. To this end, we first conducted the research and exploration on the agronomic procedures for the propagation of some of the “two hybrids” from 1973 to 1974. In 1975, we conducted comprehensive prevention and control of twelve varieties (strains) of the six major crops in the audience. Pure “three garden” construction. By 1978, basically solved the old problems of hybrids. In the same year, the total breeding area for original breeding species was 1,839 mu, accounting for 84.7% of the total cultivated land area and accounting for 93% of the total breeding area. 43 million jins of national seedlings were handed in, accounting for 90% of the total grain output, of which 400,000 jin were original ones, accounting for 93% of the total number of seed breeders. Now this section of breeding