Clonostachys Rosea selected by nematicidal screening and its efficacy against Meloidogyne incognita in a greenhouse

Meloidogyne incognita, one of the most important root-knot nematodes of crops, is still mainly controlled with synthetic agrochemicals. Toward finding eco-friendly alternative controls such as biocontrol fungi or fungal extracts, here fungi were screened in vitro for nematicidal potential, then evaluated for efficacy against M. incognita in greenhouse tomato plants. Forty fungal extracts were also tested at 300 mu g mL(-1) against second-stage juveniles of M. incognita. Then the strain that produced the most active extract was added (six treatments, mycelium/conidia) to nematode-infested soil in a pot with tomato plants. Agronomic and reproductive variables were measured after 92 days. The best nematicidal extract was from Clonostachys rosea TH27 (LD50 = 375 mu g mL(-1)), which reduced the number of galls, eggs and females in tomato roots and slightly improved agronomic traits compared with untreated plants. For control of M. incognita in pots in protected conditions, 2 g of inoculum per pot (5 kg) is recommended. Our findings confirmed that C. rosea mycelia has potential for control of M. incognita in tomato plants in the greenhouse.