一、良种繁育体系及其理论根据一个新品种育成之后,建立一个科学的良种繁育体系,对于保持纯度及生活力是很重要的。过去沿用的原原种——原种——良种——生产田的良种繁育程序,对于保持纯度是起着重要作用的。但近年来也有人认为混杂并不一定影响产量,甚至主张采用两个品种进行混合种植。在如何提高种子生活力,从而增加作物产量方面,除了从种子生理的 First, the breeding system and its theory According to a new breed breeding, the establishment of a scientific breeding system of breeding, to maintain the purity and vitality is very important. The original seed used in the past - original seed - seed - field breeding program of breeding, plays an important role in maintaining purity. However, in recent years, some people think that mixing does not necessarily affect the yield, and even advocates the use of two varieties for mixed planting. In terms of how to improve the viability of seed and thus increase the crop yield,