| Abstrakt: |
Lecanicillium saksenae is an indigenous isolate of entomopathogenic fungus from soils of Vellayani, Kerala with high speed of kill in hemipteran pests. Nematophagous nature of the fungus unveiled in the preliminary studies prompted to explore, identify and to evaluate the nematicidal metabolites present in it. Secondary metabolites produced by the fungus were detected by culturing it as per OSMAC method. The HR-LCMS and GC-MS spectra revealed a multitude of structurally diverse and biologically active metabolites which included nine nematicidal compounds. The major nematicidal metabolites identified through HR-LCMS analysis were hydroxyl quinone, 2, 6, pyridine dicarboxylic acid, dodecyl benzene sulfonic acid, 4-hydroxy benzaldehyde, nicotinic acid, harmine and oleamide. GC-MS analysis revealed 2, 6 pyridine dicarboxylic acid (dipicolinic acid), harmine, hexadecanoic acid and octadecanoic acid. Bioefficacy studies carried out with the crude toxin revealed its toxicity to juveniles of root knot nematode. Crude toxin at 50 ppm and above caused 100% mortality of J2, 48 hrs after treatment. Hence the study highlighted that L. saksenae is a promosing bioagent not only for the managenment of insect pests but also for the plant parasitic nematodes. [ABSTRACT FROM AUTHOR] |
