INHERITANCE OF ANTHER CULTURE RESPONSE IN PERENNIAL RYEGRASS (LOLIUM-PERENNE L)

Genetic control of the capacity to respond to anther culture in perenn ial ryegrass was studied in F-1 offspring from crosses between 11 clon es selected for anther-culture response ('inducers') and 10 clones sel ected from breeding material on the basis of good agronomic performanc e. Large differences in anther-culture response were observed between the two types of parent, with inducer clones producing an average of 1 0.7 green plants per 100 anthers, compared with only 0.3 for breeding clones. Hybrid populations produced an average of 2.2 green plants per 100 plated anthers, which is 7.3 times the response of the breeding m aterial. This improvement was mainly due to a 9.4-fold increase in the percentage of green plants regenerated from hybrid populations to 4.7 % compared to an average of 0.5% from breeding clones. Most of the GCA (general combining ability) in the experiment was contributed by the breeding material, constituting 55.8, 100.0 and 36.7% of genetic varia tion among hybrids for embryo formation, regeneration and green plant percentage, respectively. Any remaining genetic variation among hybrid s was predominantly due to SCA (specific combining ability) effects, w ith percentages of 44.2 and 63.3%, respectively, for embryo and green plant formation. These results are discussed with respect to the possi ble exploitation of genes controlling anther-culture response for hapl oid production in breeding programmes of perennial ryegrass.