DOUBLED HAPLOIDS FOR STUDYING THE INHERITANCE OF QUANTITATIVE CHARACTERS

T. M. Choo ¹

¹ Research Station, Agriculture Canada, P. O. Box 1210, Charlottetown, Prince Edward Island, Canada, C1A 7M8

By using a doubled-haploid population derived from F₂ plants, additive and additive x additive genetic variances, as well as the number of segregating genes, can be estimated. An F₂-derived doubled-haploid population may contain almost 50% more of the best recombinant than an F₁-derived population. However, the best recombinant occurs in the same frequency in the two populations when there is no linkage between genes. The difference in the frequency of the best recombinant between F₂- and F₃-derived populations is small. This implies that the doubled-haploid method using F₂ plants provides only slightly less opportunity for recombination than the conventional breeding methods of self-pollinating crops. In the absence of additive epistasis, a weighted mean of recombination values can be estimated using an F₂-derived population and its parental lines. When additive epistasis is present, it can be estimated from doubled-haploid populations derived from two backcrosses. Studies on the linkage of quantitative characters are needed for determining whether doubled haploids should be produced from F₂ or from F₁ plants in a breeding program.

This article has been cited by other articles:

				T.-M. Choo, K. M. Ho, and R. A. Martin Genetic Analysis of a Hulless Covered Cross of Barley Using Doubled-Haploid Lines Crop Sci., July 1, 2001; 41(4): 1021 - 1026. [Abstract] [Full Text] [PDF]