EFFECT OF SUBSTRATE, AUXIN SOURCE AND AUXIN OVERPRODUCING MUTANTS OF ECTOMYCORRHIZA HEBELOMA CYLINDROSPORUM ROMAGNESI IN ROOTING OF TWO QUINCE CLONES (EM A AND BA 29) MICROSHOOTS

The effect of strength of solid growth media (WPM, MS), porous substrates (vermiculite or mixtures of perlite and peat, 3:1 ratio) enriched with liquid ¼ WPM, presence of auxins (IBA, NAA, IAA) for various periods, as well as the inoculation of media with cultures of auxin overproducing mutants of ectomycorrhiza Hebeloma cylindrosporum on rooting of two clones of quince (EM A and BA 29) microshoots was studied. Rooting of EM A microshoots proved to be very much affected by salt and auxin concentration. Rooting percentage of EM A microshoots reached 100% in perlite/peat (3/1 ratio) supplemented with liquid ¼ WPM containing 0.1 mg/L NAA and transferred to free auxin media after 1 week, whereas BA 29 succeeded the best rooting percentage (50%) in the same media containing 1 mg/L NAA for 4 weeks. Rooting percentage of EM A noticed in vermiculite reached 100%, irrespective of the auxin source (1 mg/L IBA, 0.1 mg/L NAA, 0.1 mg/L IAA), while that of BA 29 reached only 42% with 0.1 mg/L IAA. Survival of rooted plantlets in vermiculite during acclimatization was very high (93,3%) for EM A, lower (70%) for BA 29. Growth media (1/4 WPM) inoculated with the mutants of Hebeloma cylindrosporum HC1, D117 or 331, resulted in 60, 13 and 20% rooting, respectively, for EM A but much lower percentage for BA 29 (13% for HC1).