Genetic Analyses of Isozyme in Lettuce, Lactuca sativa, and its Relatives

Abstract

Polymorphisms were observed in 14 enzyme systems in the following Lactuca species, lettuce, L. sativa, and its relative wild species, L. serriola, L. saligna, L. virosa and L. indica; 6 loci of the 3 enzymes, GOT, PGI and 6-PDH, were found to be dimeric. The segregation analysis of the F₂ progeny between lettuce and L. serriola revealed 4 loci, Got-1, Got-2, Pgi-2 and Pdh-2 and a linkage among 3 loci, Got-2, Pgi-2 and Pdh-2. Band intensity of the somatic hybrid (hexaploid) between lettuce and L. indica showed that the hybrid is composed of 4 genomes of lettuce and 2 genomes of L. indica. Thus, the genes in the 6 loci are considered to be useful genetic markers for the breeding of lettuce.