Management Strategies: Pochonia chlamydosporia and IPM of Plant-Parasitic Nematodes in Temperate Crops

Abstract

Few studies have reported findings on the use of Pochonia chlamydosporia for the management of plant-parasitic nematodes under field conditions. In this chapter we describe experiences of P. chlamydosporia application in temperate crops grown in the UK, Norway and Poland. To date, the fungus has been recovered from different endoparasitic nematodes from a range of locations across Europe. Pochonia chlamydosporia is an egg parasite as well as a saprophyte and plant endophyte and is primarily applied as a biological control agent to reduce nematode multiplication. In the UK, several field and micro-plot experiments have demonstrated that the fungus is capable of causing ca 50% reductions in the multiplication of Globodera pallida in potatoes. Further work was undertaken to evaluate the compatibility between P. chlamydosporia applications and the fungicide azoxystrobin which is used for managing the soil borne fungus Rhizoctonia solani. Although P. chlamydosporia is sensitive to azoxystrobin, there is evidence to suggest that it may not affect its efficacy as a biological control agent. In Norway, the fungus has been isolated from various cyst nematodes (Heterodera spp. and Globodera spp.), however, under in vitro conditions it was found to lose pathogenicity. Work undertaken in Poland has shown that strains of P. chlamydosporia can reduce populations of H. schachtii in sugar beet. Sugar beet grown in a 3 year rotation in combination with a mustard green manure increased egg parasitism by P. chlamydosporia in comparison to other treatments which included the addition of straw or manure. Further work is discussed on the ability of strains of P. chlamydosporia to parasitize eggs of Meloidogyne incognita, M. hapla and M. arenaria at a range of temperatures.