Integrated Two Biocontrol Agents For Control Of Root-knot Nematode And Preliminary Investigation On Dayu County Citrus Nematode

Root knot nematode(RKN)is a kind of plant parasitic nematode with extensive host.It can cause serious harm to crops,and the annual economic losses caused by root knot nematodes can be as high as hundreds of billions per year.Because of people’s awareness of environmental protection,people pay more attention to biological control of root knot nematode disease.The combination of biocontrol strains to control nematode diseases,which will provide technical support.For this purpose,the effect of application of two biocontrol strains to Meloidogyne incongnita was evaluated.Investigation nematode infestation on Dayu cuonty citrus will provide basis for the control of citrus nematode disease.We got the following results:1.Testing combination effects of biocontrol fungi Paecilomyces lilacinus PL36-1-5and Streptomyces avermitilis for integrated control of root-knot nematode,the results showed that PL36-l-5 and Streptomyces avermitilis had no obvious antagonism,and they can be intermixed.The combination of two agents could enhance in the parasitism rate of nematode eggs,the hatching inhibition rate of nematode eggs and the lethal rate of second-stage juvenile of RKN.Pot experiments showed that,combination liquid spore of S.avermitilis and PL36-1-5,can improve the growth of pea,and significantly improve the control to RKN2.It was tested whether 11 pesticides with concentration in field influenced PL36-1-5 growth.We found that almost all of the pesticides had inhibition for mycelial growth and spore activity of PL36-1-5 at the concentration range of the tested.This means that the combination of PL36-1-5 and t pesticides is not be best measurement.3.The samples of citrus orchard of Dayu county had high nematode incidence,and the nematode number was up to 1632/100 m L soil and 13.56/g root.Nematode damage to citrus should be paid more attention.