Mycoflora and yield of Agaricus bisporus under different initial nitrogen levels in compost

Abstract

Six initial nitrogen levels viz., 0.5, 1.0, 1.5, 1.75, 2.0 and 2.5 % were taken in wheat straw and compost was prepared by long method. In all more than 35 different mesophilic fungi were isolated with different N levels and at different turnings. Incidence of Stachybotyrs spp and Stilbum  nanum was recorded up to 1.0 % N only while negligible incidence of Sepedonium maheshwarianum was noticed up to 1.5 %. After that its incidence rose sharply and was maximum at 2.5 % N level. After termination of the composting phase (28 days) it was treated with DDVP + carbendazim (0.1 and 0.025%, respectively) and Furadan (Carbofuran 0.05%). Third set (untreated) was taken as control. Treatment of compost with DDVP+ Bavistin and Furadan reduced the number and population of fungal flora including the fungi mentioned above. Highest yield was obtained when compost was treated with DDVP + Bavistin at 1.75% N which was statistically at par with 1.5 N. In all twenty four thermophilic fungi were also isolated at various N levels. Scytalidium thermophilum and Humicola spp. were dominantly isolated at all N levels.