경남(慶南) 진주지방(晋州地方)에서 1977년(年), 78년(年)에 통일계(統一系) 품종(品種)인 밀양(密陽) 23호(號)와 일반계(一般系) 품종(品種)인 추청(秋晴)벼를 재배(栽培)하여 4종(種)의 멸구 매미충의 밀도(密度)를 조사하였다. 애멸구는 전체적(全體的)인 발생량(發生量)이 적었으나 추청(秋晴)벼에서 밀도(密度)가 높았으며 끝동매미충은 추청(秋晴)벼, 흰등멸구 벼멸구는 밀양(密陽) 23호(號)에서 각각 밀도가 높았다. 시기별(時期別) 분포(分布)에서 추청(秋晴)벼에서는 6, 7, 8월(月)에 끝동매미충의 분포비율(分布比率)이 높았으며 9월(月)에는 벼멸구가 많았다. 밀양(密陽) 23호(號)에서는 7, 8월(月)에는 흰등멸구가 8월(月)하순(下旬) 부터 9월(月)에는 벼멸구의 분포비율(分布比率)이 높았다.
The densities of plant-and leaf hoppers were examined by direct counting the rice plant of two varieties, Milyang 23 and Chucheongbyeo, in Chinju. The densities of the small brown planthopper(SBPH), Laodelphax striatellus, and Green rice leafhopper(GLH), Nephotettix cincticeps were higher on Chuchungbyeo than on Milyang 23 throughout the season, whereas those of white backed planthopper(WBPH), Sogatella furcifera, and Brown planthopper(BPH), Nilaparvata lugens were high on Milyang 23. Seasonal densities of planthoppers were varied with rice plant growth, on Chucheong field, GLH was the predominant species from June to August and BPH was in September, but in Milyang 23 field, WBPH was more abundent from July to August and BPH was increased from late August and was the highest on September.