中部山地蕉園耕作方法對萎縮病消長及增産效果試驗初步(三年)報告

Abstract

中部由坡地蕉園不同耕作管理方法，對萎縮病發生消長之形響據，初步試驗結果，各種處理間有顯著差異。三試區三年平均發病率以灌溉處理最低(20.6%)，其次爲施猪糞尿與覆蓋，病株不更新的對照最高(28.4%)。不同處理對香蕉植株生育與産量影響差異不顯著，乃因試驗期間尚短，各種處理之效果尚未顯著，其中以覆蓋處理最高。 每公頃減去萎縮病損失產量後之估計產量，三試區平均以覆蓋處理最高，每公頃達14563.8公斤，其次爲灌溉，每公頃14196.72公斤，比病株不更新的處理各增産12.18%與9.35%，足見山坡地蕉園覆蓋與冬旱期間灌溉，以保持土壤水分之管理，對減少萎縮病之發生提及高單位面積之産量有良好的效果。又隨時處理萎縮病病株，並更新補植健苗，亦可抑止萎縮病之蔓延，而減少病害損失。 Experiment on the influences of cultural practices on the incidence of bunchy top disease and yield of banana was conducted by the Chia-yi Agricultural Experiment Sation, TARI, from 1967 to 1969 at three localities, namely, Lun-Lung, Yung-Hsing and Chun-Kun, in Nantou Hsien where the bunchy top disease often attacked seriously on banana plantations. Seven treatments of, different cultural practices and farm managements were adopted in the experiment as follow: A. Applying with pig's excreta once two months interval and replanting the diseased plants. B. Mulching with straws and replanting the diseased plants. C. Irrigating once two weeks interval during dry season and replanting the diseased plants. D. Planting cover crop and replanting the diseased plants. E. Spraying with 800 times of Malathion to kill the vector insect and replanting the diseased plants. F. No treatment but replanting the diseased plants. G. Without any treatment as control. Based on the preliminary results obtained, it was showed significant differences among the various treatments on the infection percentage of bunchy top. All trentments were less infected by the disease than those of control. The irrigation treatment gave the best result on reduction incidence of bunchy top disease. (Table 1). However, there were no significant differences to be found out among the treatments on the plant growth and yield of banana (Table 2). The losses of yield due to the bunchy top disease were very greatly in each treatment, As it was estimated from the bunch weight and infection percentage of bunchy top, all treatments outyielded from 1.58% to 12.18% than the control one. Moreover, the mulching and irrigating treatment showed the highest yield increased 12.18% and 9.35%, respectively, as compared with the control (Table 3). Therefore, it is important to indicate that the management by holding up soil moisture, such as mulching or irrigating, during the dry season on hillside plantations not only can reduce the percentage of bunchy top disease but also can increased the production of banana. On the other hand, if all diseased plants were destroyed as soon as symptoms appeared, so that they could not be transmitted by banana aphids to healthy plants, the disease could efficiently be reduced the proportions.