A Collagenolytic Fungus, Cunninghamella elegans, for Biological Control of Plant-parasitic Nematodes

Abstract

The root-galling index of tomatoes inoculated with Meloidogyne javanica was decreased 70% when collagen was used as a soil amendment (0.1% w/w) and 90% when the amendment was supplemented with the collagenolytic fungus Cunninghamella elegans. The root-galling index was reduced 80% when the fungus was homogenized in collagen culture medium and added to soil without collagen supplement. Culture filtrates of the fungus C. elegans, grown on collagen as a single source of carbon and nitrogen, immobilized M. javanica second-stage juveniles and inhibited egg hatch. Root galling was reduced when tomato plants were inoculated with filtrate-treated juveniles. Culture filtrates reduced the motility of Rotylenchulus reniformis and Xiphineraa index, but they had less effect on Anguina tritici and almost no effect on Ditylenchus dipsaci. Cunninghamella elegans had collagenolytic, elastolytic, keratinolytic, and nonspecific proteolytic activities when grown on collagen media, but only chitinolytic activity when grown on chitin media. Key words: Anguina tritici, biological control, chitinase, collagen, collagenase, Cunninghamella elegans, Ditylenchus dipsaci, elastase, fungus, keratinase, Meloidogyne javaniea, Rotylenchulus reniformis, Xiphinema index.