Effect of cultural condition on biomass production of some Nematophagous fungi as biological control agent

Abstract

Nematophagous fungi include a group of fungal antagonists to nematodes. Thenematophagous fungi have been suggested as promising candidates for biologicalcontrol of plant parasitic nematodes. Impacts of different pH levels, temperature, lightintensity, carbon and nitrogen source were tested on the growth of five nematophagusfungi under in vitro conditions. Three isolates of Trichoderma harzianum T7, T8, andT14, one isolate of Pochonia chlamydosporia var. chlamydosporia and one isolate ofArthrobotrys oligospora were tested. The results of experiment indicated that thegrowth of isolates of Trichoderma harzianum was maximum in pH range of 7.00-8.00. The best growth of Pochonia chlamydosporia var. chlamydosporia andArthrobotrys oligospora was in 4.00-7.00. Effect of temperature differs between rangeof 15-30°C, for isolates of Trichoderma harzianum was 20-25°C, Pochoniachlamydosporia var. chlamydosporia was 15-20°C, and Arthrobotrys oligospora was20-25°C. Maximum growth of two isolates of Trichoderma harzianum T7, T8 andPochonia chlamydosporia var. chlamydosporia was in darkness. Best growth of oneisolates of T. harzianum (T7) was in light and maximum growth of Arthrobotrysoligospora and Trichoderma harzianum T14 occurred in 12 h light and 12h dark. Thebest source of nitrogen for Trichoderma harzianum (T8,T14) was Nitrate potassium,while Nitrate ammonium was the best nitrogen source for (T7).The maximum growthof A. oligospora and P. chlamydosporia occuerd in Nitrate sodium. Between carbonsources Arabinose are suitable for A.oligospora and Trichoderma harzianum (T7).Themaximum growth of P. chlamydosporia and T. harzianim (T14) occuerd in the use offructose. Best growth of T. harzianum (T8) was in Mnitole.