Biocontrol of Meloidogyne incognita by Metarhizium guizhouense and its protease

Publication date: Available online 7 August 2018Source: Biological ControlAuthor(s): Apivit Thongkaewyuan, Thanunchanok ChairinAbstractCrude extracts of the fungus Metarhizium guizhouense PSUM02 grown on protein- enriched medium showed high proteolytic activity and produced one main protein indicated as fungal protease with 33 kDa molecular mass. The protease activity had high stability when incubated at 10 or -20 oC for 6 months. The use of Metarhizium spores (1 × 104 spore mL-1) in combination with its protease (354.1 ± 2.2 U mL-1) completely inhibited hatching of the root-knot nematode Meloidogyne incognita within 24 hour. Moreover, the mortality of juveniles increased to 100% at 48 hours post treatment. The results were significantly different (p < 0.05) from Metarhizium spores or protease individually, as well as from extraction buffer and distilled water controls. Metarhizium spores suspended in crude protease rapidly germinated in 24 hours and then mycelia invaded the immature eggs of M. incognita, while the eggs containing juveniles and the hatched juveniles were resistant. SEM observations showed extensive damage to eggshell and cuticle when treated with Metarhizium spore and protease, either individually or in combination. This is the first report on biocontrol potential of M. guizhouense against M. incognita. The combination of Metarhizium spores and protease has enhanced potential to develop into a safe and reliable method for plant parasitic nemat...
Source: Biological Control - Category: Biology Source Type: research