Читать книгу Principles of Plant Genetics and Breeding - George Acquaah - Страница 116

Selection is the most important process for altering population gene frequencies by plant breeders. Its effect is to change the mean value of the progeny population from that of the parental population. This change may be greater or lesser than the population mean, depending on the trait of interest. For example, breeders aim for higher yield but may accept and select for less of a chemical factor in the plant that may be toxic in addition to the high yield. For selection to succeed there must be:

1 Phenotypic variation for the trait to allow differences between genotypes to be observed.

2 The phenotypic variation must at least be partly genetic.