The root zone applications of a systemic insecticide, carbofuran, were evaluated for their impacts on the brown planthopper, Nilaparvata lugens (Stål), and spider populations in the greenhouse and rice paddy fields. In the green house experiments, no BPH nymphs were hatched at root zone treated on 40 to 50 day-old rice, while around 20 to 54 nymphs per pot were emerged in broadcasting and foliar spray treatments. This indicates that the root zone treatment can kill the eggs of BPH effectively. This is the first study ever demonstrated the high egg mortality of BPH due to the root-zone application. In the field experiments, the density of BPH in root zone treated plots were four to six times lower than in broadcasting and foliar spray plots at the 21 days after application. The BPH outbreaks and hopper-burns were observed at all treatments except the root zone treated plot at the 28 days after application. The root-zone application did not impact on the spider population, while foliar spray killed most of all spiders just one day after application. The densities of spider in foliar spray plots were always lower than in root-zone treated and control plots. The results indicated that the root-zone application of carbofuran can control BPH effectively without adverse effects to the spiders inhabited on the paddy field.

Root zone application of several systemic insecticides was tested for control of the brown planthopper, Nilaparvata lugens (Stål), in Vietnam and Korea. In Vietnam, the results indicated that carbofuran showed the highest nymphal mortality in all experiments, followed by imidacloprid and carbosulfan. When the insecticides were applied on 10-day old rice, carbofuran was shown almost 100% N. lugens mortality at six days after treatment and the efficacy was extended to twelve days after application. In Korea, various root-zone application methods were tested with carbofuran and carbosulfan. The results showed that carbofuran was the most active in reducing the egg hatching rates. When root-zone treated on 40-50 day-old rice in a greenhouse, no nymphs were hatched in carbofuran treated pots, while average of 20 nymphs were emerged in carbofuran broadcasting pots. Especially the number of nymphs emerged in carbosulfan foliar spray was 54 nymphs per pot even at the eight day after application, which was higher than in control pots. This is the first study ever demonstrated the high egg mortality of N. lugens on rice due to the root-zone application of insecticides.

의약용 Capsuel에 넣은 입제형 살충제 BPMC, Carbofuran, Cartap, Chlorphenamidine-HCl, Cytrolane, Diazinon의 단일회 수도근부처리로서 수도 전생육기간에 걸친 이화멸충, 멸구, 매미충류 및 Virus 병의 방제효과를 검정하기 위해 포장시험을 실시하여 아래와 같은 결과를 얻었다. (1) 이화명충은 발생이 적었기 때문에 약제간에 큰 차이는 볼 수 없었지만 약제처리후 50일에서 이화명충 1화기 심고경율 Cartap 0, Carbofuran 0.1, Chlorphenamidine 0.4, Cytrolane 0.5, BPMC 1.8, Diazinon 2.2이었으며 2화기 백수율은 BPMC에서 이었을 뿐 그밖에 약제처리구에서는 백수가 없었다. (2) 끝동매미충과 애멸구에 대해서는 BPMC와 Diazinon 처리구에서 비교적 낮은 밀도를 보였다. 벼멸구에 대해서는 BPMC와 Carbofuran에서 서식밀도가 현저히 낮아 그 방제효과가 좋았으나 Cartap, Chlorphenamidine, Cytrolane 및 Diazinon의 효과는 거의 기대할 수 없었다. (3) 오갈병의 발병주율은 Carbofuran이 , Cytrolane , Chlorphenamidine , Diazinon BPMC, Cartap , Diazinon 입제수면 시용 , 무처리 로서 Carbofuran 처리구에서 오갈병의 발병율이 가장 낮았다. 줄무늬잎마름병의 발생은 전혀 없었는데 그 원인은 통일벼는 줄무늬잎마름병에 저항성품종이기 때문인 것 같다. (4) 벼의 수량은 무처리 5,814kg/ha에 비하여 Carbofuran 6,649kg, Cytrolane 6,340kg, BPMC 6,315kg, Chlorphenamidine 6,265kg, Cartap 6,164kg, Diazinon 5,944kg, Diazinon 입제 수면시용 6,102kg로서 Carbofuran 처리구에서 벼의 수량이 가장 높았다. (5) Carbofuran 처리구에서 높은 수량을 보인 것은 Carbofuran 처리구에서 멸구, 매미충류의 밀도가 낮았고 오갈병의 발병율이 낮은데서 온 결과인 것 같다.