IN-VITRO CONSERVATION OF MUSA GERMPLASM - EFFECTS OF MANNITOL AND TEMPERATURE ON GROWTH AND STORAGE

In vitro studies in Musa were undertaken to devise a simple and econom ical protocol applicable to a wide array of genotypes. Effects of trea tments to slow growth on the health and storability of cultures were i nvestigated using six Musa cultivars. In vitro cultures survived for 1 0-12 months at 25-degrees-C on Murashige and Skoog medium supplemented with 1.0 mg l-1 benzyladenine. Longevity of cultures was not directly related to their growth rates. Incubation at low temperature (15-degr ees-C) had least effect on shoot growth but doubled the shelf-life of cultures to 20-22 months compared with 10-12 months at 25-degrees-C. M annitol (2-4%) enhanced the storage period by 2-3 months but had delet erious side effects at higher concentrations. Considering the running cost and the risks of germplasm loss under various slow-growth treatme nts, 25-degrees-C storage on shoot culture medium was more appropriate for Musa. Over 100 diverse collections have been maintained using the above protocol.