对于常规的优良品种,农家可以自己留种,但要选择隔离条件较好、管理到位、生长发育整齐一致的田块作为留种田块。鉴于不同部位的果实或种子遗传能力不同,为了防退化,保持优良品种的种性,以下作物留种时,要选择强优势区域的果实或种子作种。早稻作为顶部遗传优势作物,早稻穗子上 For the conventional good varieties, farmers can keep their own species, but to choose better isolation conditions, management in place, the same growth and development of the plots as remaining farming plots. In view of the different parts of the fruit or seed genetic ability is different, in order to prevent degradation, to maintain the good varieties of species, the following crops to stay species, to choose a strong area of ​​fruit or seeds for seed. Early rice as the top genetic advantage of crops, early rice on the ears