Vdovychenko Zh.V., Antonyuk M.Z., Ternovskaya T.К.

Influence of gametocidal chromosome 4S^l on the segregation ratio in genetic analysis of common wheat lines

Cytology and Genetics 2003, v 37, number 5, 49–56

Using experimental data on genetic analysis of introgressive lines for the character «hairy leaf sheath» controlled by the «cuckoo» chromosome 4S^l, the algorithm for calculation the theoretical segregation ratio in F₂ was developed. Segregation distortion is caused by non-viability of the majority of gametes lacking the chromosome 4S^l. The frequency of functioning gametes without the chromosome 4S^l is determined by the probability p versus the theoretically expected ratio 7 nonviable : 9 viable ones. Since segregation involves two characters, gamete viability and hairiness, the ratio 15 hairy : 1 hairless was used as a base for search of the frequency p by maximum-likelihood method using 16 populations F₂ from crossing the lines differing in the character studied.