Presence of phenolic compounds in aqueous extract of vermicompost had been implicated as one of the reasons for its nematicidal effect. A few good review papers are available, which may be helpful.

it depends deeply to diet of worm. for example if leaves of neem were consumed , vermicompost will be useful for your goal.

When 2 approaches used together give more effect than the sum of 2 together the treatments are synergistic. They also may be additive non active or negative acting. The ability of Trichoderma harzianum and vermicompost to give positive results can be related to differences in the mechanisms of interaction and the leverage of these differences. Trichoderma is a chitolytic hyperparasite and this make make it useful for the root knot. Vermicompost is a very nutritionally complete amendment that has ability to support plant resistance reaction and biocontrol microbials. Trichoderma harzianum has ability to stimulated the plant resistance pathways. The enhanced nutrition reaction of vermicomposts and complemented plant biochemical responses work together positively. Hope this gives you some ideas for clarifying the interactions.

thank you all.... Yes Paul I found your explanation quite useful, root knoy nmatode already involved in forming disease complexes with differnt category of interaction which u have mentioned. May be antagonism also becoming additive here..

These articles are on nematicadal enzyme chitinase. These will be helpful for you

https://www.researchgate.net/publication/282153514_Enhanced_nematicidal_potential_of_the_chitinase_pachi_from_Pseudomonas_aeruginosa_in_association_with_Cry21Aa

https://www.researchgate.net/publication/311668087_Improvement_of_chitinase_Pachi_with_nematicidal_activities_by_random_mutagenesis

https://www.researchgate.net/publication/275278845_Effects_of_domains_modification_on_the_catalytic_potential_of_chitinase_from_Pseudomonas_aeruginosa

Best wishes

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