EFFECT OF ENVIRONMENTAL CONDITIONS GROWTH OF PADDY STRAW MUSHROOM (VOLVARIELLA VOLVACEA)*

Abstract

The research aims to detect the best medium ,temperature and PH in growth of Paddy straw mushroom (Volvariella volvacea ) under laboratory conditions. the results showed that there were differences in response between the tested fungal strains V97, VD, V35 and V9 in growth on synthetic culture media PDA, YEA and MEA after five days of incubation. V97 strain gave the highest mean growth on the three culture media( 8.729 cm ) while V9 strain gave the lowest mean growth 2.708 cm. The natural culture media, Paddy straw, Wheat straw,Corn cobs and Palm wastes gave best growth for the fungal strains ,the mean growth for all the strains ranged 5.625-9.000 cm with the superior of the two strains VD. and V35 which gave the highest mean growth 9.000 cm diameter on all used culture media, while V9 strain gave the lowest growth on the four used growth media ,The mean growth 6.703 cm. The results of the effect of temperature on growth of V. volvacea strains showed that the two strains VD. and V35 gave the best growth on 30°C and 35°C, the mean colony diameter reached 9.000 cm diameter for the two strains, while the two strains V97 and V9 gave the highest myceilal growth on 35°C which reached 9.000 cm diameter , the lowest growth recorded of VD and V35 strains on 25°C which reeched 4.000 and 5.375 cm respectively. The two strains V9 and V97 gave the lowest mean growth on 45 °C which recorded 2.625 and 6.906 cm for the two strains respectively. Results of study the effect of PDA culture media and PH on growth of V. volvacea strains showed that the optimum PH ranged between7.5-8.0,The two strains VD and V9 gave the highest growth (9.000 cm) in PH 7.5, while the highest mean growth for the two strains V97 and V35 (9.000 cm) was recorded in PH8.0.