The potential of Beauveria bassiana and Metarhizium anisopliae in controlling the root-knot nematode Meloidogyne incognita in tomato and cucumber

Abstract

Meloidogyne incognita is one of the most important plant parasitic nematodes. This study was conducted to determine the nematicidal potential of Beauveria bassiana and Metarhizium anisopliae against M. incognita. B. bassiana and M. anisopliae spore suspensions and bio -nematicide, Purpureocillium lilacinum were applied. B. bassiana and M. anisopliae revealed considerable nematicidal activity against M. incognita in tomato and cucumber. The gall index decreased gradually from 8.0 for control to 3.2, 2.0 and 2.2 for B. bassiana, M. anisopliae and P. lilacinum in tomato, respectively. The highest reduction (%) in gall formation (control index) was calculated as 75.2 % in M. anisopliae treated group for tomato. The gall index was 7.6 for control, but decreased to 3.6, 2.0 and 2.2 for B. bassiana, M. anisopliae and P. lilacinum in cucumber, respectively. The highest control index was 71.7 % for M. anisopliae in cucumber. The number of the second instar juveniles of M. incognita was recorded as 2240 for control. However, this value reduced to 508, 332 and 328 by B. bassiana, M. anisopliae and P. lilacinum in tomato, respectively. The highest control indexes for the second instar juveniles were 85.2 % and 85.3 % for M. anisopliae and P. lilacinum in tomato, respectively. Alike, the highest control indexes were 84.9 % and 85.7 % for the same applications in cucumber, respectively. B. bassiana and M. anisopliae displayed also positive effect on the number of leaves, dry and fresh root weights of tomato. The results showed that B. bassiana and M. anisopliae can be considered as an alternative.