THE INFLUENCE OF PARENTAL GENOTYPE AND PERIOD OF POLLINATION ON HAPLOID BARLEY PRODUCTION IN HORDEUM-VULGARE L X H-BULBOSUM L CROSSES

Two factors, period of pollination and parental influence, were investigated in a programme of doubled haploid barley production under glass house conditions. In one experiment, 3 F1 barley hybrids were crossed with 3 clones of Hordeum bulbosum L. and with their pollen mixture. In another one, 7 F1 barley hybrids were crossed with H. bulbosum L. using a pollen mixture of two of the clones used in the first experiment. In the second experiment crosses were done during April, May, June and July. The number of differentiated embryos cultured per florets pollinated (EC/FP) the number of barley haploid plantlets per embryos cultured (HP/EC) and the number of haploid plants per ear pollinated (HP/EP) were recorded. There were significant differences between the F1 barley hybrids, the H. bulbosum L. clones and the periods of pollination. The rate of haploid plants per ear pollinated (HP/EP) varied between 0.5 to 2.9. The pollination period generally had an effect on all hybrids with an important increase when approaching the natural period of pollination and there was no difference between May, June and July for EC/FP whilst April had the lowest values. The best results were obtained in April and May for HP/EC.