GRAPEVINE PLANT REGENERATION FROM CELL SUSPENSIONS AND INFLORESCENCE FORMATION IN VITRO UNDER THE INFLUENCE OF DIFFERENT VITAMIN AND MINERAL ELEMENT LEVELS IN NUTRIENT MEDIA
06.00.00 Agricultural sciences
Effects of different levels of vitamins (thiamine, pyridoxine and nicotinic acid) and macro-elements (MS, NN and PG) on development of globular, heart- and torpedo-stage embryos and plantlets with green cotyledons and on shoot production from them were studied in grapevine interspecific hybrids: cvs. ‘Bianca’, ‘Podarok Magaracha’ and ‘Intervitis Magaracha’. Pro-embryogenic calli were derived from petiole explants on solid full-strength NN medium supplemented with different levels of 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzyladenine (BA) for each cultivar and used to initiate cell suspensions in liquid NN medium supplemented with 1 mg L-1 2,4-D and 0.2 mg L-1 BA. The following formulations of media were optimal for different stages of somatic embryogenesis and for plantlets with green cotyledons development: liquid NN medium supplemented with 0.5 mg L-1 BA for globular embryo formation; liquid HTE medium (with PG macro-elements, thiamine and pyridoxine at 5 mg L-1 each and 0.5 mg L-1 nicotinic acid): supplemented with 0.2 mg L-1 BA for heart-stage embryo development, supplemented with 0.1 mg L-1 indole-3-acetic acid (IAA) and 30 mg L-1 sodium humate for torpedo-stage embryo development and supplemented with 0.5 mg L-1 gibberellic acid (GA3) for the growth of plantlets with green cotyledons. Solid MS medium modified by the addition of nicotinic acid, pyridoxine and p-aminobenzoic acid (PAB) at 5 mg L-1 each, 0.5 mg L-1 thiamine and 0.5 mg L-1 BA was best efficient for shoot production from plantlets. Inflorescence formation in regenerated plants of cv. ‘Podarok Magaracha’ grown on solid hormone-free PG medium was induced by addition of nicotinic acid, pyridoxine and PAB at 5 mg L-1 each, 0.5 mg L-1 thiamine and 0.2 mg L-1 BA into liquid modified HTE medium for growth of plantlets with green cotyledons and into solid modified MS medium for shoot production from them.