Influence of anther pretreatment and culture medium composition on the production of barley doubled haploids from model and low responding cultivars

Different pretreatments were given to anthers of barley before culturing, a nd their effects assessed on the frequency of embryos and green doubled hap loid plants produced. Mannitol pretreatment was better than cold pretreatme nt for some low responding cultivars. Optimal concentration of mannitol for pretreatment depended on cultivar. Low responding genotypes needed a highe r concentration of mannitol than responsive ones. The addition of Ficoll to liquid medium increased the number of embryos and green plants. The influe nce of the growth regulators 2,4-D and TIBA was assayed using ten cultivars of barley grown in Spain. The anti-auxin TIBA gave good embryo production with some of the low responding cultivars. Two row-type cultivars always pr oduced higher number of embryos and green plantlets than six row-type. The application of these modifications to 10 F-1 hybrids with potential agronom ic value, allowed the production of almost 1000 doubled haploid plants from only 3500 anthers. Up to two doubled haploid plants per flower were produc ed from the cross Monlon x Sonja.