The nematode trapping fungus Arthrobotrys oligospora Fresenius, a potential bio-control agent suppressing the root-knot nematode Meloidogyne incognita on tomato plants.

AIM Isolation and characterization of the nematode trapping fungus, Arthrobotrys oligospora. Investigate the suppressive and predacious activities of the fungus against Meloidogyne incognita. Studying the potentiality of A. oligospora in controlling root-knot caused by M. incognita on tomato plants. METHODS AND RESULTS Arthrobotrys oligospora (MRDS 300), was isolated from sandy soil samples collected from Al-Beheira, Egypt. In vitro experiments revealed a high efficiency of the fungus in capturing and suppressing Meloidogyne incognita second juveniles (J2 ). Microscopic observations showed that the fungus develops adhesive traps consisting of loops of hyphae. Moreover, an in vitro experiment showed that the culture filtrate of A. oligospora has a high toxic effect to the nematode. Pot experiments carried out in two seasons (2018-2019) showed that A. oligospora significantly suppressed root knot on tomato plants caused by M. incognita. The number of females, galls and nematodes in different developing stages were significantly reduced. The treatment with A. oligospora had a prominent effect in enhancing plant growth. CONCLUSION A. oligospora has significant suppressive and predacious effects against root knot nematode, M. incognita. The fungus develops different forms of trapping devices in addition to secreting toxic metabolites to M. incognita. The fungus has a plant-growth promoting effect. Significant impact of the study A. oligospora (MRDS 300) is a potential biological control agent that can be utilized in controlling the root-knot diseases caused by Meloidogyne incognita.