臺灣東部水稻胡麻葉枯病稻田肥力改進試驗

Amelioration of Soil Fertility for Reducing brown Spot Incidence in the Paddy Field of Eastern Taiwan

李子純(T. S. Lee Wang) ； 許兩順(L. S. Hsu) ； 林慶喜(C. H. Lin)

《中華農業研究》 29卷1期 (1980/03) Pp. 35-46

https://doi.org/10.29951/JARC.198003.0005

摘要

由於66年度在本省東部地區所作土壤肥力與水稻胡麻葉枯病的關係研究試驗中，發現東部地區胡麻葉枯病的發生係由於土壤中有效性矽錳及鉀的含量偏低之故。爲尋求減輕此種病害的發生以提高水稻產量的適當方沃，乃於67年度繼續在東部選取發病較重地點五處，施用矽礦滓(4t/ha)，倍量鉀肥(120 kg K2O/ha)及硫酸錳(100 kg/ha)，觀察其對病害及產量的影響。
經一年兩期作試驗的結果，發現施用前述三者的單獨效果以矽礦滓最佳，使一期作五試區平均增產11%，其次爲倍量鉀肥，平均增產2%，而硫酸錳則僅增產1%。當矽礦滓與倍量鉀肥合施時，兩期作分別增產15及16%。而三者同時施用時，效果更好，使一、二期作的病害分別減輕48及34%，產量也因此分別增加16及21%。
又由罹病指數及稻谷產量與水稻體內的營養素關係發現其問關係最密切者除去年度已發現之SiO2及K/Mg比外，更與稻體內SiO2/K比有極密切的關係，由此更證實作物生長中必煩注意其體內營養素的平衡，而施用過量鉀肥時更須注意矽之施用，以保持其與鉀間的適當比例。

並列摘要

A soil fertility survey conducted at 30 sites in eastern Taiwan in 1977 revealed that the severity of brown spot disease of rice was intimately correlated with deficiencies of available manganese, silica and potassium, and that the low yield in that area was related with the widespread incidence of brown spot disease. Based on these results, five field trials were set up by supplying the said elements on severely disease-affected fields in Hualien Hsien in 1978.
Among various treatments, silicate slag (4 t/ha) proved to be the best amendment. It increased grain yield by 11 % in the first rice crop (average of 5 field trials), while doubling the rate of potash (120 t/ha K20) increased the yield by 2 % and only 1% increase was obtained by manganese sulfate (100 kg/ha) application. When silicate slag and extra potash were combined, it increased grain yield by 15% in the first and 16 % in the second crop. The effect was excellent when the three elements were applied together; this treatment decreased the disease index by 48 and 34 %, and increased grain yield by 16 and 21% in the first and second crops, respectively.
In addition to the close relations of SiO2 content and K/Mg ratio in rice plant with disease index and rice yield found in the previous experiment, SiO2/K ratio was also found to be highly significantly correlated with them. These findings proved the importance of maintaining multifactor balance of nutrient elements in rice cultivation, particularly with respect to silica or extra potash fertilization.