在生产斗争中,广大劳动人民创造出许许多多的新品种,它们具有一系列的优良性状,这些性状是稳定的、遗传的,但同时也不断地发生着变异。遗传性的稳定和变异构成了品种内部的一对矛盾。毛主席教导我们:“事物内部矛盾着的两方面,因为一定的条件而各向着和自己相反的方面转化了去,向着它的对立方面所处的地位转化了去。” In the struggle for production, the working people have created many new varieties with a series of excellent traits that are stable and inherited, but are constantly being mutated. Hereditary stability and variation constitute a contradiction within the variety. Chairman Mao teaches us: “The two contradictions within things have been transformed toward the opposite of themselves because of certain conditions, and they have been transformed toward their opposite status.”