Preparation Of Biocontrol Seed Coating And Its Efficiency In Prevention Of Meloidgyne Incognita

Meloidogyne spp.,a pathogen of root-knot nematodes,have a very wide range of host,which can harm almost all crops.Furthermore,the nematode cuticles can protect the root-knot nematodes from damage outside,which makes it much difficult to prevent and treat this disease.This research aimed at screening nematode efficient antagonistic fungi,developping effective prevention and control of root knot nematodes Biological Seed Coating Agent,in which their effects under greenhouse and field conditions were evaluated.The results were as follows:1.Screened out three strains of antagonistic fungi against Meloidgyne incognita.Paecilomyces lilacinus(PLN),Trichoderma harzianum(T11-w)and Acremonium implicatum(ACR),were selected out from six plants of epiphytes with effect of biological prevention.Under the three strains of antagonistic fungi Meloidgyne incognita,the fatality rate of Meloidgyne incognita J2 was up to 100%after 60 hours.The cucumber root-knot loss rate of Paecilomyces lilacinus(PLN),Trichoderma harzianum(T11-w)and Acremonium implicatum(ACR)fermentation and mixed matrix could reach 60%.2.Developed thin film seed coating and pelleted seed coating agent that prevented and controlled of Meloidgyne incognita.Three kinds of film seed coating agents and pelleted seed coating agent of biocontrol fungi could increase the germination percentage evidently,and promote the growth of cucumber seedling.The seed coating agent processed with Acremonium implicatum(ACR)had the best performance.The germination potential of thin film coating seed could reach 93.2%,and germination rate 94.6%,and the plant height 25.95 cm,while its pill type coating seed germination potential could be up to 96%,96.3% germination rate,plant height 32.75 cm,however the germination potential the blank control only 88.4%,of and germination rate only 90%,plant height 20.6 cm.So,the pelleted seed coating agent has better performance in the promotion of germination percentage and growth of cucumber seedling.3.Measured control efficiency of biocontrol fungi seed coating agent on Meloidgyne incognita.The green house pot experiment showed that there was obvious control efficiency on root-knot nematode by using two kinds of seed coating agents of three strains,especially the seed coating agent processed with Trichoderma harzianum(T11-w)and Acremonium implicatum(ACR).The root-knot loss rate of film seed coating agent,to Trichoderma harzianum(T11-w)and Acremonium implicatum(ACR)could reach 65% and respectively 61%.And pelleted seed coating agent,to Trichoderma harzianum(T11-w)and Acremonium implicatum(ACR)could reach67% and respectively 70% under the same condition.Field testing showed that seed coating agent processed with Trichoderma harzianum(T11-w)and Acremonium implicatum(ACR)had better performance than the positive results of chemical control in the root-knot nematode control efficiency.The control effects of film seed coating agent and pelleted seed coating agent to Acremonium implicatum(ACR)could reach 74.4% and 77.4% respectively.Similarly,film seed coating agent reached 71.8% and pelleted seed coating agent reached 72.2% processed with Trichoderma harzianum(T11-w).However,the positive control of abamectin control effect was only 66.9%.