Effect of population levels of Aphelenchoides swarupi and Aphelenchus avenae inoculated at spawning on mycelial growth of mushrooms and nematode multiplication

Abstract

An experiment was conducted to investigate the effects of population levels of Aphelenchoides swarupi and Aphelenchus avenae, inoculated at spawning time, on the mushrooms Agaricus bisporus, Agaricus bitorquis and Calocybe indica. Mycelial growth was reduced with time, depending upon nematode species and the population levels. After 40 days of spawning, mycelial growth of A. bisporus was reduced to 1.7% of that of the uninoculated control at an initial inoculum of 1,000 individuals of A. swarupi/1,000 g of compost, compared to 28.2% with 10 individuals/1,000 g. Although, Aphelenchus avenae restricted mycelial growth less than A. swarupi but the trend with population level was similar. Although Agaricus bitorquis showed comparatively better mycelial growth than A. bisporus when inoculated with both nematodes, the effect of initial population levels of the nematodes on mycelial growth was also severe. The mycelial growth of C. indica was only slightly affected by the nematodes and was of 99.5% at the initial inoculum of 10 individuals of either A. swarupi or A. avenae which declined to 96.1 and 96.7%, respectively, at the initial inoculum of 1,000 nematodes per 1,000 g compost. Both A. swarupi and A. avenae multiplied on A. bisporus and A. bitorquis, the rate of multiplication being higher at low initial inoculum and vice versa. Only negligible nematode population densities and no reproduction occurred on C. indica.