Different biocontrol agents via; Streptomyces antibioticus, Bacillus subtilis, Arbuscular mycorrhizal fungi, Trichoderma harzianum and Pasteuria penetrans were tested against root-knot nematode Meloidogyne javanica in vitro and in vivo on tomato plants. Results of in vitro experiment showed that all the tested microorganisms decreased significantly percentage of nematode hatching compared to the control. The greatest inhibition of egg hatching was with B. subtilis, where it gave 100%, 99%, 95%, 98% at 24, 48, 72 and 96 hours, respectively. In greenhouse experiment, results showed that the number of galls, egg masses, females/root system and number of juveniles/250 g soil were significantly reduced as a result of biocontrol agent treatments where the highest reduction percentages per root system obtained with the treatment B. subtilis it gave 81% (in galls), 88% (in egg masses), 83% (in females) and 71% (in eggs/egg masses), whereas the highest reduction in juveniles recorded with mixture treatment (93%). Applications of biocontrol agents particularly AMF, S. antibioticus and mixed treatments led to a marked increase in P. penetrans infected females / root system. Mixture of bioagents contributed in increasing percentage of AM colonization in plant roots, mean number of AMF spores in soil and NPK percentages in plants. This promoted the plants to grow in a good healthy state.
Researcher Name: Neveen M. Galal; Ebtsam, M. Morsy and Osama N. Massoud
Newspaper: N. Egypt. J. Microbiol. Vol. 32, May, 11-27
Year: 2012
KeyWords: Microbial biocontrol agents, compost, root-knot, nematode (Meloidogyne javanica)