Seasonal Abundance and Species Composition of &lt;i&gt;Nephotettix&lt;/i&gt; spp., in Endemic and Non-Endemic Areas of Rice Tungro Virus Disease in South Sulawesi Province, Indonesia

Andi Nasruddin,Muhammad Danial Rahim,Fatahuddin Fatahuddin

doi:10.3844/ojbsci.2016.130.136

Abstract

Rice tungro disease is semi-persistently transmitted by five species of leafhopper. Nephotettix virescens Distant and N. nigropictus Stal. (Homoptera: Cicadellidae) are predominant species in South Sulawesi with vectoring efficiencies of 83 and 27%, respectively. Relative composition of those species affects the RTV incidence in the field. The purpose of the study was to determine the presence and abundance of those species in RTV-endemic and non-RTV-endemic areas in South Sulawesi. The presence of both species at different altitudinal levels was also determined. The results showed that N. virescens was present in both RTV-endemic and non-RTV-endemic areas. In RTV-endemic area, N. virescens was the only species found. Higher number of N. nigropictus existed in non-endemic area with less intensive use of insecticide than in non-endemic area with intensive use of insecticides. Nephotettix virescens was found in the low (< 100 m above sea level) and mid (500-700 m) altitudes but not in the high elevation (> 1000 m). In the high altitude, only N. nigropictus existed. This species was also present in the mid and lower levels in non-RTV-endemic area with lower intensity of insecticide use.

Highlights

Tungro disease caused by Rice Tungro Virus (RTV) is the most devastating viral disease of rice in South and South East Asian countries
Nephotettix virescens was the only vector species collected from rice fields in South Sulawesi (Siwi et al, 1987) when RTV epidemics occurred throughout the province
This species was the only rice leafhopper species found in the endemic area and non-endemic area with more intensive use of insecticide, except in Maros, one individual of N. nigropictus was collected from the field

Summary

Introduction

Tungro disease caused by Rice Tungro Virus (RTV) is the most devastating viral disease of rice in South and South East Asian countries. During the period of 19691983 the disease damaged 168,000 ha of rice in Indonesia; 100,000 ha of which occurred in the Province of South Sulawesi alone during the period of 1972-1975 (Hibino, 1987); and by 1992 the national figure had risen to 243,693 ha (DBPT, 1992). Rice tungro virus is transmitted by five species of rice leafhopper, Nephotettix virescens Distant, N. nigropictus Stal., N. malayanus Ishihara et Kawase, N. parvus Ishihara et Kawase and Recilia dorsalis Motschulsky in semi-persistent fashion (Hibino, 1983; Siwi et al, 1987). Nephotettix virescens was the only vector species collected from rice fields in South Sulawesi (Siwi et al., 1987) when RTV epidemics occurred throughout the province. Since N. virescens is the most efficient RTV vector, its composition in the field is closely related to the extent of tungro disease (Suzuki et al, 1992). No information is available on the current distribution and composition of both vector species in the province

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