二化螟蟲에 對한 水稻의 抵抗性에 關한 硏究

Studies on the Host Resistance of the Rice Plant to the Rice Stem Borer, Chilo suppressalis Walker

二化螟蟲에 對한 水稻의 品種間抵抗性 差를 밝히기 爲하여 選拔된 抵抗性 및 感受性品種들을 供試하여 一化期와 二化期의 被害莖數, 그리고 二化期의 在蟲數, 被害度, 史體重 等을 調査하여 다음과 같은 結果를 얻었다. (1) 水稻品種에 對하여 二年間에 걸친 抵抗性反應의 傾向이 一致하였으므로 眞正한 品種間의 抵抗性이 存在한다고 생각되었다. (2) 供試된 水稻의 12品種에 있어서 一化期와 二化期의 被害莖數는 顯著한 差를 나타냈으며 一, 二化期의 被害莖數는 正의 相關을 나타냈다. (3) 水稻의 抵抗性 및 感受性品種은 在蟲數 및 被害度에 있어서도 顯著한 差를 나타내었다. (4) 在蟲數와 蟲體重問에는 正의 相關을 나타내었는데 이는 害蟲集團의 密度效果 以外의 다른 抵抗性 要因이 存在함을 暗示하는 것으로 생각되었다.

The study was conducted to investigate the difference of varietal resistance to rice stem borer(Chilo suppressalis Walker) in rice plant. And the varieties were used 6 resistants and 6 susceptibles, which were selected by field observations made in previous experiment. The number of damaged plants, number of survived insects and the degree of damage were examined to determine the host resistance of rice plant under the field condition. (1) It was considered that the real varietal resistance was existed, because the results obtained were similar tendency of resistance to previous experimental results. (2) The number of damaged plants, which caused by 1st and 2nd generation of rice stem borer larvae, showed the significant positive correlation indicating no evidence of ovipositional preference. (3) And also there were significant difference between resistant and susceptible varieties in both number of survived insects and the degree of damages. (4) There was significant positive correlation coefficient between the number of insects survived and the body weight of insects, suggesting that there must be existed some resistance factors instead of the population density which decreases the size of insects.