臺灣中部地區稻熱病流行學之研究

Studies on the Epidemiology of Rice Blast Disease in Central Areas of Taiwan

簡錦忠(C. C. Chien) ； 蔡武雄(W. H. Tsai) ； 楊涌祚(Y. Z. Yang) ； 劉清(C. Liu)

《中華農業研究》 33卷2期 (1984/06) Pp. 169-180

https://doi.org/10.29951/JARC.198406.0009

摘要

自臺灣中部三個地區（臺中縣霧峰鄉、彰化縣社頭鄉和臺南縣白河鎮）設置之試驗田，連續於民國67年及68年兩年第一期稻作，在二個或四個品種上，用二種方法調查自然發生的葉稻熱病病斑面積率，並收集試驗田空中的稻熱病菌分生胞子及記錄氣象資料（包括平均溫度、最高溫度、最低溫度、溫度範圍、溫度在21℃~24℃時數、平均相對濕度、最高相對濕度、最低相對濕度、相對濕度範圍、相對濕度在90%以巨時數、露水時間、雨量及降雨日數），利用相關和複迴歸統計分析，探討本省中部的氣象條件與田間稻熱病病勢進展的關係。分析結果為不同地區、年度、病斑面積率的估量（調查）方法以及品種間對稻熱病罹病程度的不同，使得各項因子對發病面積率的影饗程度亦有所差異。但在各地區無論67或68年，大部份品種的病斑面積率與病斑出現後日期及累積胞子數之問有極高的相關，因此選擇此兩因子及平均溫度、溫度21~24℃時數、平均相對濕度、相對濕度90%以上時數與雨量等七種因子與各品種病斑面積率做複迴歸分析，結果顯示此七種因子之複相關係數頗高。但累積胞子數係隨病斑之增加而增加，故在實際利用於預測上較有困難。亦即應用此七種因子來預測病斑面積率應屬相當有效。

並列摘要

Experimental fields were set up where mean, maximum and minimum temperatures, duration of temperature between 21℃ and 24℃, mean, maximum and minimum relative humidities, dew duration, precipitation, number of rainy days, number of spores trapped as well as naturally infected disease intensities for different varieties were recorded at three locations in central Taiwan, i.e., Wufen, Taichung; Shetou, Changhua and Paiho, Tainan, for the first crop of rice in 1978 and 1979. Two methods were used to obtain disease intensity. One is by taking the actual counts of blast lesions at levels of R, M and S and calculating the percent disease area according to A=0.164×S+0.077×M+0.024×R and the other is by visual assessment, based on government published standard charts of disease rating.
Results from the regression and correlation analyses showed the effects of the afor-mentioned factors on the disease intensity to vary according to varieties, methods of measuring disease intensity, years as well as locations. However, the partial regression coefficients of days after emergence of lesions and/or the cumulated number of spores on disease intensity were significant in most cases. This indicated that the number of spores could be used effectively to forecast the epidemic development of rice blast disease.