The rice planthopper,Sogatella furcifera,is a piercing-sucking insect pest of rice,Oryza sativa.It is responsible for significant crop yield losses,and has developed moderate to high resistance to several commonly use...The rice planthopper,Sogatella furcifera,is a piercing-sucking insect pest of rice,Oryza sativa.It is responsible for significant crop yield losses,and has developed moderate to high resistance to several commonly used chemical insecticides.We investigated the effects of the insect fungal pathogen Isaria javanica,alone and in combination with the chemical insecticide dinotefuran,on S.furcifera under both laboratory and field conditions.Our results show that I.javanica displays high infection efficiency and mortality for different stages of S.furcifera,reducing adult survival,female oviposition and ovary development.Laboratory bioassays showed that the combined use of I.javanica with a low dose(4-16 mg L^(-1))of dinotefuran resulted in higher mortality in S.furcifera than the use of I.javanica or dinotefuran alone.The combined treatment also had more significant effects on several host enzymes,including superoxide dismutase,catalase,peroxidase,and prophenol oxidase activities.In field trials,I.javanica effectively suppressed populations of rice planthoppers to low levels(22-64%of the level in untreated plots).Additional field experiments showed synergistic effects,i.e.,enhanced efficiency,for the control of S.furcifera populations using the combination of a low dose of I.javanica(1×10^(4) conidia mL^(-1))and a low dose of dinotefuran(~4.8-19.2%of normal field use levels),with control effects of>90%and a population level under 50 insects per 100 hills at 3-14 days post-treatment.Our findings indicate that the entomogenous fungus I.javanica offers an attractive biological control addition as part of the integrated pest management(IPM)practices for the control of rice plant pests.展开更多
Rice planthoppers are notorious plant sap-feeding pests which cause serious damage.While several microbes in rice planthoppers have been broadly characterized,the abundance and diversity of bacteria and fungi in field...Rice planthoppers are notorious plant sap-feeding pests which cause serious damage.While several microbes in rice planthoppers have been broadly characterized,the abundance and diversity of bacteria and fungi in field planthoppers are largely unknown.This study investigated the bacterial and fungal community compositions of Chinese wild rice planthoppers Laodelphax striatellus and Sogatella furcifera using parallel 16S rRNA gene amplicon and internal transcribed space region sequencing.The bacteria varied sig-nificantly between the species and were partitioned significantly by sex,tissues and host environments in each species.The majority of bacteria were affiliated with the genera Wol-bachia,Cardinium,Rickettsia and Pantoea.The abundance of Wolbachia was negatively correlated with that of Cardinium in both planthopper species.Compared with bacteria,the abundance and diversity of fiungi did not differ between sexes but both were enriched in the gut.The bacterial community as a whole showed no significant correlation with the fungal community.The majority of fungi were related to Sarocldium,Alternaria,Malasseria,Aspergillus and Curvularia.A phylogenetic analysis revealed that these fungi were closely related to botanic symbionts or pathogens.Our results provide novel insights into the bacteria and fungi of rice planthoppers.展开更多
基金funded by grants from the Science and Technology Planning Project of Guangzhou,China(202002020029)the Science and Technology Planning Project of Guangdong Province,China(2019B020217003)+1 种基金the National Key R&D Program of China(2018YFD02003)the National Key Technology Support Program of China(201303019-02)。
文摘The rice planthopper,Sogatella furcifera,is a piercing-sucking insect pest of rice,Oryza sativa.It is responsible for significant crop yield losses,and has developed moderate to high resistance to several commonly used chemical insecticides.We investigated the effects of the insect fungal pathogen Isaria javanica,alone and in combination with the chemical insecticide dinotefuran,on S.furcifera under both laboratory and field conditions.Our results show that I.javanica displays high infection efficiency and mortality for different stages of S.furcifera,reducing adult survival,female oviposition and ovary development.Laboratory bioassays showed that the combined use of I.javanica with a low dose(4-16 mg L^(-1))of dinotefuran resulted in higher mortality in S.furcifera than the use of I.javanica or dinotefuran alone.The combined treatment also had more significant effects on several host enzymes,including superoxide dismutase,catalase,peroxidase,and prophenol oxidase activities.In field trials,I.javanica effectively suppressed populations of rice planthoppers to low levels(22-64%of the level in untreated plots).Additional field experiments showed synergistic effects,i.e.,enhanced efficiency,for the control of S.furcifera populations using the combination of a low dose of I.javanica(1×10^(4) conidia mL^(-1))and a low dose of dinotefuran(~4.8-19.2%of normal field use levels),with control effects of>90%and a population level under 50 insects per 100 hills at 3-14 days post-treatment.Our findings indicate that the entomogenous fungus I.javanica offers an attractive biological control addition as part of the integrated pest management(IPM)practices for the control of rice plant pests.
基金This work was supported by the National Natural Science Foundation of China(No.31672035 and 31871976)the startup grant from Nanjing Agricultural University(No.804015 and 80900224).
文摘Rice planthoppers are notorious plant sap-feeding pests which cause serious damage.While several microbes in rice planthoppers have been broadly characterized,the abundance and diversity of bacteria and fungi in field planthoppers are largely unknown.This study investigated the bacterial and fungal community compositions of Chinese wild rice planthoppers Laodelphax striatellus and Sogatella furcifera using parallel 16S rRNA gene amplicon and internal transcribed space region sequencing.The bacteria varied sig-nificantly between the species and were partitioned significantly by sex,tissues and host environments in each species.The majority of bacteria were affiliated with the genera Wol-bachia,Cardinium,Rickettsia and Pantoea.The abundance of Wolbachia was negatively correlated with that of Cardinium in both planthopper species.Compared with bacteria,the abundance and diversity of fiungi did not differ between sexes but both were enriched in the gut.The bacterial community as a whole showed no significant correlation with the fungal community.The majority of fungi were related to Sarocldium,Alternaria,Malasseria,Aspergillus and Curvularia.A phylogenetic analysis revealed that these fungi were closely related to botanic symbionts or pathogens.Our results provide novel insights into the bacteria and fungi of rice planthoppers.
