有利变异

可以认为秋水仙碱诱变处理，引起了玉米可遗传的有利变异。

Therefore we may think that inducement of colchicine can cause maize advantageous variation .

拟泡状细胞是提高植物抗旱性和抵御外界不良影响的结构，是自然选择中植物显现的有利变异之一；

Similar bulliform cell is structure of improving plant drought resistance and resisting badness effect from environment , is one of plant appearing avail variation in natural selection ;

利用或创造变异，通过人工定向选择将有利的变异固定下来，可实现新品种的培育。

Using or creating variation , and fixing down the favorable genes through the artificial selection , may realize the breeding of the new varieties .

但是其他有利的基因变异，比如那些允许成年人消化牛奶的基因变异，在人类历史上只是最近才出现的，却迅速传播开来。

But other advantageous gene variants that appeared only recently in human history , such as those allowing adults to digest milk , became widespread very rapidly .