Study On Fermentation Conditions Of Paecilomyces Lilacinus And Preliminary Research On Study Method Of Interaction Mechanism Between Paecilomyces Lilacinus And Nematode

Plant parasitic nematodes are one of the important limiting factors in cropproduction throughout the world. Using chemical agents and nematicides cause manynegative effect, while biocontrol can overcome these disadvantages. Paecilomyceslilacinus is one of nematopHagous fungi which has been examined over the past twodecades for potential use as agent for the control of plant pathogenic nematodes inagriculture. The facultative egg parasite is sometimes also able to infect larval andadult female nematodes, but it is most aggressive against eggs. Up to date,Paecilomyces lilacinus has been produced industrializedly as a biological nematicide.This research include three parts. The first ,optimal fermentation parameters ofPaecilomyces lilacinus have been determined;The second, different indexes ofPaecilomyces lilacinus have been determined and relativity of different indexes alsoanalyzed; The third,interaction between Paecilomyces lilacinus and nematode hasbeen researched primarily on molecule.The results are as follows.We conclude that optimal temperature is 28℃;,liquid volume is 100ml in conicalflask with the volume of 250ml, speed is 120 rpm,culture time is 7-9d, pH is6-9,inoculation number is one mycelium discs which diameter is 5mm in 250mlconical flask with 150ml liquid volume by the determination of fermentationparameters of Paecilomyces lilacinus. we also detect spore reproductivity of PL1 issuperior to that of PL2 with different fermentation parameters,so PL1 is better thanPL2.we achieve a liquid culture medium of Paecilomyces lilacinus with excellentproductivity of spore: PS+eggyolk by the determination of spore concentration,mycelium weight,virulence and enzyme activity of culture solution with differentliquid culture medium,which provides materials for industrialized production, sporeconcentration and mycelium weight firstly display increase with time,followinginvariableness,however, for virulence and enzyme activity of culture solution,somefluctuate up and down,others increase.we detect that relativity between sporeconcentration and mycelium weight is higher, virulence and enzyme activity ofculture solution lower by correlative analysis.we design five primer sets:β-tubulin,chittinase,serine proteinase,mannanase,β-actin by Paecilomyces lilacinus and nematode.we have testified thatfrontal four primer sets are specifical primers of Paecilomyces lilacinus by analysis of primer specificity, which is base for further study on interaction mechanism betweennematode and Paecilomyces lilacinus.The novelty of this research lie that we research interaction betweenPaecilomyces lilacinus and nematode on gene level, wo achieved four specifiealprimer sets by many experiments, which is base for further relative quantification; andwe achieve a cheap liquid culture medium of Paecilomyces lilacinus with excellentproductivity of spore: PS+eggyolk,which is excellent material for industrializedproduction.