The effect of the fungus Pochonia chlamydosporia on the root-knot nematode Meloidogyne incognita in pots.

摘要

Two application rates (5000 and 60 000 chlamydospores/g of soil) of the nematophagous fungus Pochonia chlamydosporia [Pochonia chlamydosporia var. chlamydosporia] (isolate 10, Rothamsted Research, UK) were tested for their effect on two infection rates of the root-knot nematode Meloidogyne incognita (450 and 1400 juveniles/plant) on tomato and pepper plants grown in pots. The presence of the fungus in soil and root, root gall index and juvenile densities in soil were assessed seven and 14 weeks after inoculation and compared with control treatments (free of fungus). In addition, egg production and egg parasitism were recorded at the first assessment. Although the fungus established in soil and parasitized the eggs, it did not reduce nematode population densities after seven weeks in both crop plants. However, significant reductions of root galling and juvenile density were recorded after 14 weeks, but only on pepper. Fungus colonization of roots was not influenced by the initial application rate of chlamydospores and remained stable in both assessments.