SELECTION OF HIGH YIELDING SINGLE SPORE CULTURES OF VOLVARIELLA VOLVACEA (BULL.FRIES) SINGER.

Volvariella volvacea is a tropical mushroom with variable biological efficiency which can be stabilized through selection of single spore cultures. Nineteen single spore cultures, MV-1 to MV19 were isolated from three healthy fruit bodies of the parent, V. volvacea, VV-11 and analyzed for growth, enzyme production and yield potential. The growth rate was maximum in single spore culture MV-7 (30mm/day). Maximum biomass production was recorded in MV-9 and MV-14 (12.8g/l in both). The activity of endo-1, 4-?-glucanase (EC 3.2.1.4), exo-1, 4-?-glucanase (EC 3.2.1.91) was maximum in MV-7 (0.0481 and 0.0369, respectively) while xylanase activity (EC 3.2.1.8) was maximum in MV-5(0.0404). The Laccase activity was maximum for MV-7 (1.61) followed by MV-3 (1.29) and MV-9 (1.16). On the basis of growth characteristics and enzyme activity six V. volvacea single spore isolates MV-6, MV-7, MV-9, MV-13, MV-14 and MV-18 were selected for yield trials on paddy straw. In comparison to yield of the parent V. volvacea, strain VV-11 (13.28 Kg/q of dry straw, respectively), two single spore strains MV-7 and MV-14 had showed higher yield (15.32 and 16.13 Kg/q of dry straw, respectively) whereas number of fruit bodies was higher for the single spore culture MV-14 (2375 no./q of dry straw). The average weight of fruit body ranged between 5.8-8.3g. During the present study, two V. volvacea single spore cultures MV-7 and MV-14 have been selected as high yielding strains.