MICROPROPAGATION OF MOTHER PLANTS OF LUCERNE (MEDICAGO-SATIVA L) FOR SOMATIC EMBRYOGENESIS

A reliable and standard method was established for micropropagation of the A70-34 selected genotype of lucerne (Medicago sativa L., genotype A70-34), aimed at reducing contamination problems, seasonal and pheno logical influences on regeneration and phytosanitary problems of the m other plants, while maintaining the regenerative potential for somatic embryogenesis of the plant tissues. Mother plants were routinely main tained for several subcultures and somatic embryogenesis was regularly obtained from the subcultured explants. Proliferation, rooting and em bryogenetic ability of plants cultured for 30 days was greater than th ose cultured for 20 days. The regenerative potential of tissues from d ifferent organs and of triturated and intact whole plants was also tes ted. Petioles were confirmed as the best source for embryogenesis as f ar as efficiency and repeatability were concerned, even though regener ation from other explant types was also achieved. Production of somati c embryos through mechanical trituration of the in vitro cultured plan ts was obtained; the regeneration ability of the triturated plants was greater than that observed in the intact plants.