RECOVERING GENETIC RESOURCES OF SOME LEGUME SPECIES OF LATVIAN ORIGIN BY PLANT TISSUE CULTURE

Accessions with no germinating seeds are a common problem in plant gene banks and researchinstitutions. our goal was to elaborate and apply an in vitro method of germination and multiplicationof old aged seeds of red and alsike clover and alfalfa. eighteen clover and five alfalfa accessionswere used for germination in vitro. most of the accessions had produced seeds more than20 years ago and the seeds did not germinate in soil. seed pre-treatment with different concentrationsof potassium permanganate, as well as addition of phytohormones, agno3 and activatedcarbon to germinating media were tested. plantlets for all germinated accessions were obtained,even in the case when seeds were 44-year-old (alfalfa). germination rate in vitro not always correlatedwith seed age and ranged from 2 to 72%. pre-treatment with potassium permanganatewas effective both for seeds sterilisation and germination stimulation. most germinated seedsformed phenotypically normal seedlings with all organs. in vitro multiplication of obtained cloverplants was performed. best results were achieved by micropropagation of stem segments approximately2 mm in length. number of finally obtained plants depended not only on seed germinationability, but also on micropropagation ability in relation to genotype, and on acclimatizationsuccess in soil after in vitro cultivation.