Pure line:(a) It is a progeny of single, self-fertilized homozygous individuals.
(b)A similar strategy is used for developing pure lines in cattle as was used in case of peas.Inbreeding increases homozygosity. Thus, inbreeding exposes harmful resessive genes that are eliminated by selection.
©It also helps in accumulation of superior genes and elimination of less desirable genes.The selection at step increases the productivity of inbred population.