Relationship between Planthoppers (Nilaparvata lugens and Sogatella furcifera) and Rice Diseases

멸구류(類)(벼멸구 및 흰등멸구)와 수도병해(水稻病害)의 복합발생피해(複合發生被害)에 관(關)한 연구(硏究)

  • LEE, S.C. (Department of Agricultural Biology, Chonnam National University) ;
  • Matias, D.M. (International Rice Research Institute) ;
  • Mew, T.W. (International Rice Research Institute) ;
  • Sorino, J.S. (International Rice Research Institute) ;
  • Heinrichs, E.A. (Department of Entomology, LSU Agricultural Center)
  • 이승찬 (전남대학교 농과대학 농생물학과) ;
  • D.M. 마티아 ;
  • T.W. 뮤우 ;
  • J.S. 소리노 ;
  • E.A. 하인리크
  • Published : 1985.09.30

Abstract

The locational preference of the brown planthopper (BPH) Nilaparvata lugens ($St{\aa}l$) and the whitebacked plant hopper (WBPH) Sogatella furcifera(Horvath) was studied on rice cultivars IR22 and IR36 as an integral part of subsequent research on insect-fungal pathogen relationships. The BPH was observed to stay consistently on the basal portion while the WBPH showed a general preference for the upper portion regardless of varieties, rice growth stages and insect population density levels. The habitat preference of both species (BPH and WBPH) was found not to be affected by the presence of the other species when both species are present on the same host plant Five rice cultivars with different reactions to BPH biotype 2 were used in the study on BPH-Rhizoctonia solani relationship: IR22 and TN1 (susceptible); Triveni and ASD7 (moderately resistant); and IR42 (resistant). Test plants were inoculated with R. solani (Kuhn) $3{\sim}4$days after insect infestation. Sheath blight disease severity/incidence was significantly higher in the treatment where BPH+R. solani were together than in the treatment with only the pathogen. Symptom expression of the disease in the BPH-pathogen combination was faster and mycelial growth was more profuse inducing the formation of more infection structures. Regardless of varietal reaction to BPH biotype 2, the degree of hopperburn was significantly higher in the combination of the two pests as compared with that of BPH alone. There could be a synergistic relationship between the insect pest and the pathogen indicated by a positive interaction between the two species.

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