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当前,大多数育种者都利用晚熟和热带种质资源改良现有材料,以拓宽其遗传基础,提高现有自交系的配合力,组配出具有高产潜力和突出特点的新杂交组合。玉米自交系的选育是玉米育种的基础,是育种的关键环节。在选育方法上,育种者大都采用二环法、回交转育法、群体改良法和诱变等多种方法,已选育出一批优良自交系用于杂交育种,取得了一定的效果。但育种者同时也发现,无论哪一种方法都存在着不足之处。笔者在8a近24个选种周期中,通过实际工作探索,利用多种方法并对这些方法的材料组建、血源配比、高代材
At present, most breeders use the late-maturing and tropical germplasm resources to improve the existing materials to broaden their genetic base and improve the combining ability of the existing inbred lines, and to formulate new hybrid combinations with high yield potential and outstanding features. Breeding of maize inbred lines is the basis of maize breeding and is the key of breeding. Breeding methods, breeders mostly use the second cycle method, backcross transfer method, population improvement and mutagenesis and other methods have been bred a group of excellent inbred lines for hybrid breeding, made a certain effect. But breeders also found that there is a downside to either approach. In the nearly 24 selection cycles of 8a in the past eight years, the author explored through practical work and made use of various methods and analyzed the materials of these methods, the ratio of blood sources,