Evaluation of biological Control potential for different Trichoderma strains against Root-Knot Nematode Meloidogyne javanica

Twenty strains of four Trichoderma species (Trichoderma harzianum, Trichoderma viride, Trichoderma koningii and Trichoderma asperellum) were evaluated for its potential to control the root-knot nematode Meloidogyne javanica. Culture filtrates from Trichoderma strains were tested in 24-well tissue culture plates for effects on Meloidogyne javanica. Chitwood egg hatch and mobility of hatched second-stage juveniles (J2) were evaluated, all the twenty Trichoderma strains showed the ability to colonize M. javanica separated eggs and second-stage juveniles (J2) in sterile in vitro assays. T. asperellum possess the strongest egg-parasitic ability and very effective against 2nd stage larvae of M. javanica. In this investigation, randomly amplified polymorphic DNA (RAPD) markers was used to estimate the genetic variations between four strains of Trichoderma asperellum (KC898190, KC898191, KC898192 and KC898193) which were previously isolated from the rhizospheres of different plants growing in Fayoum Governorate, Egypt as a new strain of T. asperellum in Egypt. RAPD assay using 6 random primers identified T. asperellum strains with 5 specific unique markers.