SOMATIC IN-VITRO CULTURE RESPONSE OF LOLIUM-PERENNE L - GENETIC-EFFECTS AND CORRELATIONS WITH ANTHER CULTURE

Genotypic effects on callus induction and plant regeneration in callus , suspension and protoplast culture, and their correlations with both phenotypic and GCA-values for anther culture response, were studied us ing 21 genotypes of perennial ryegrass. Differences between genotypes accounted for approximately 40% of the total variation for callus indu ction and initial callus growth, and 59 and 83% of the variation in ca llus culture for regeneration percentage and percentage of green plant s. Effects of genotypes were less pronounced in suspension culture, wh ere suspensions from the same genotype often behaved differently. Some suspension cultures retained their capacity for green plant regenerat ion for almost two years, repeatedly producing 80-100% green regeneran ts during this period. Genotypes with high regeneration percentage and a large proportion of green plants from callus culture were also supe rior in suspension culture for both regeneration performance and longe vity. Regeneration percentage and percentage of green plants were unco rrelated, and probably under different genetic control. While capacity for green plant formation from the different genotypes showed no corr elation between anther culture and somatic in vitro culture, a positiv e correlation was observed between the regeneration percentages in som atic in vitro culture and anther culture (r = 0.44-0.85***), suggesti ng some common genetic control of the two systems.