- Direct Parasitism & Infection
- Fungi (Verticillium, Pochonia, Aspergillus, Purpureocillium) and certain bacteria (B. siamensis) directly parasitize and penetrate the eggs, larvae, and female adults of nematodes, consuming their internal nutrients.
- Enzymatic & Toxin Degradation
- Chitinase & Protease Production: Aspergillus niger and Purpureocillium lilacinum secrete chitinase to dissolve eggshells. B. nematocida secretes serine/neutral proteases to degrade nematode tissues.
- Pore-Forming & Cellular Disruption: B. thuringiensis utilizes crystal proteins (Cry6A, Cry55A) and metalloprotease (Bmp1) to puncture and destroy the nematode gut and cuticle.
- Respiratory Inhibition: Aspergillus niger uniquely blocks nematode respiration by inhibiting NADH-fumarate reductase.
- Rhizosphere Colonization & Competition
- B. firmus, B. velezensis, and B. methylotrophicus rapidly colonize the plant rhizosphere and surfaces, creating a physical barrier and outcompeting pathogens for infection sites.
- Induced Systemic Resistance (ISR) & Immunity
- B. cereus, B. velezensis, B. siamensis, and Rhodovulum sulfidophilum trigger the plant’s own defense systems/immune response, enhancing its ability to resist subsequent nematode and viral attacks.
- Nematode Attraction & Trapping
- B. nematocida B16 stands out by secreting 7 distinct chemical attractants to actively lure nematodes to the bacteria for targeted killing.
lin-chemical.com 