The role of chitinase from Lecanicillium antillanum B-3 in parasitism to root-knot nematode Meloidogyneincognita eggs

Abstract

B-3 fungal isolate was isolated from soil samples of Gwangju in Korea. Based on morphological and phylogenetic analysis, it was designated as Lecanicillium antillanum B-3 (syn. Verticillium antillanum B-3). The fungus was a chitinolytic-nematophagous microorganism. B-3 chitinase activity from 0.5% swollen chitin broth medium reached the highest level on the sixth day and then plateaued until 12 days. B-3 isolate showed the high rate of parasitism on Meloidogyne incognita eggs with more than 90% infection rate on the third day after treatment. B-3 crude chitinase damaged the eggshell structures more than 78% based on lactoglycerol staining data at a final protein concentration of 14.6 µg mL⁻¹ on the fourth day following treatment. Partially purified chitinase with molecular 37 kDa from DEAE-Sephadex chromatography also showed damaging effect on the eggs. These results suggested that chitinase from B-3 isolate was responsible for degradation of M. incognita eggshell structures.

Keywords:

• Chitinase
• chitinolytic fungi
• Lecanicillium antillanum B-3
• Meloidogyne incognita

Acknowledgements

This work was supported by the Korea Science and Engineering Foundation (KOSEF) through the National Research Lab. Program funded by the Ministry of Science and Technology (No. M10300000322-06J0000-32210).