Detection of Variability among the Strains of Volvariella volvacea (Bull. Ex Fr.) Sing, and Volvariella bombycina (Schaeff.) Sing.Using RAPD analysis

摘要

A total of 9 strains consisting of both V. volvacea (5 cultivated strains viz., CBE TNAU 1401 to 1405; 2 wild strains viz., CBE TNAU 1505 and 1516) and V. bombycina (one cultivated strain CBE TNAU 1406 and one wild strain CBE TNAU 1504) were evaluatedto ascertain the variation in their morphological, cultural and molecular characters. Among strains tested, CBE TNAU 1505 was the best strain, which showed earliness in spawn run, more biomass production in unit time and more chlamydospores production with high density. In the trials conducted with partially decomposed paddy straw, the highest yield of 1041.2 g per 5 kg of substrate with an average biological efficiency of 20.8 per cent was recorded with CBE TNAU 1505. Molecular detection of Volvariella strains through 5.8S rDNA regions showed that ITS primers had amplified a product size between 700 and 740 bp. RAPD - PCR phylogenetic analyses revealed 2 major clusters. V. volvacea strains showed approximately 13 per cent genetic similarities with the strains of V. bombycina.