研究彙報第十二期 ， Page 51-59 ，出版時間：1986-6， 詳細內容

水稻縞葉枯病主要感染時期之推定及適期防治試驗

作者：陳慶忠　柯文華

摘　　要

　　縞 葉 枯 病 為 近 年 台 灣 第 一 期 稻 作 之 重 要 蟲 媒 毒 素 病 害 。 其 病 徵 潛 伏期 約 25～38 日 ， 視 接 種 時 之 季 節 (氣 溫) 及 水 稻 植 齡 而 異 。 在 田 間 約 有 86% 之 罹 病 株 的 病 徵 在 插 秧 後 61～100 日 出 現 。 根 據 田 間 斑 飛 蝨 棲 群 密 度 消 長 ， 縞 葉 枯 病 接 種 至 發 病 所 需 潛 伏 期 及 病 株 出 現 時 期 等 資 料 ， 推 測 中 部 地 區 水 稻 縞 葉 枯 病 主 要 感 染 時 期 在 插 秧 後 40～60 日 間 。 依 據 前 述 主 要 感 染 時 期 擬 定 八 種 不 同 防 治 處 理 ， 經 田 間 試 驗 證 明 第 一 期 水 稻 插 秧 後 40～60 日 間 ， 當 第 一 世 代 班 飛 蝨 密 度 開 始 增 加 時 ， 噴 佈 25% Buprofuzin W.P. 1500 倍 液 一 次 ， 防 治 媒 介 昆 蟲 斑 飛 蝨 (Laodelphax striatellus) 使 縞 葉 枯 病 之 罹 病 株 率 比 不 處 理 區 約 減 少 55% ， 推 測 實 施 大 面 積 防 治 媒 介 昆 蟲 時 ， 將 可 更 有 效 控 制 縞 葉 枯 病 之 發 生 。

Studies on the Time of Rice Stripe Virus Infection and Field Experiments on Disease Control

Ching-Chung Chen and Wen-Fa Ko

Summary

　　Stripe has become a major virus disease of the first rice crop in Taiwan since its wide occurrence in 1984. The disease showed a latent period for symptoms varying from 25 to 38 days with the seasons (temperature) and plant age at time of inoculation under the field condition. We infer from the data on the population fluctuation of Laodelphax striatellus, and the date of symptom appearance in the field that there were two main peaks of RSV infection which caused substantial yield losses in the first rice crop. The first peak of infection was largely due to the adults of vector of the overwinter host plants to infect rice seedlings before or up to 20 days after transplanting. The infected plants exhibited symptoms at about 40 to 60 days after transplanting. The second infection peak was caused by nymphs or adults of the first generation and it occurred at 21 to 60 days (mainly at 40 to 60 days) after transplanting. The disease symptom appeared at 61 to 100 days after transplanting. The population density of L. striatellus between the first and second infection peak was very low. Field survey indicated that about 86% of the diseased plants of the 1st rice crop were infected with RSV at the 2nd infection peak with symptoms appearing 61 to 100 days after transplanting.

　　Field trials on the control of stripe were conducted at Ta-Ya and Ta-Tsuen in Taichung county and Changhua county, respectively in the 1st rice crop in 1986. The results indicated that Carbofuran 3G applied at the rate of 10 g. per seedling box (60 x 30 x 4 cm) at stage of green colorization of the rice seedlings and same chemical applied at a rate of 90 g. per box 24 hr before mechine transplanting to suppression the 1st infection peak of RSV caused about 35% reduction of disease incidence when compared with untreated controls.

　　For the suppression of the 2nd infection peak, application of Buprofezin made between 40 and 60 days after transplanting, i.e. immeadiately after the population of the 1st-generation of vector insect was to increase, reduced the disease incidence by 55%. Other treatments such as Carbofuran 3G applied at 30 days after transplanting showed no significant reduction of disease incidence (p=0.05) over the control plots. A better result would be expected when a large scale of insecticide application is adopted to control the vector of RSV at the critical time pointed out above.