鐘麻根瘤線蟲病與D-D合劑施用之效果（第三報）

Effect of D-D Mixture on the Occurrence of Root Knot of Kenaf (Hibiscus Cannabinus L.) No. 3

蔡雲鵬(Y. P. Tsai) ； 游江海(K. H. Yu) ； 劉文珍(W. C. Liu)

《中華農業研究》 7卷2期 (1957/11) Pp. 14-22

https://doi.org/10.29951/JARC.195711.0003

摘要

(1) 經栽盆及田間試驗之結果，最適當之D-D注藥深度爲15公分。
(2) 500公升／公頃D-D，其注藥深度爲15公分時，對10-30公分深土壤中根瘤線蟲有完全撲減之效。對0-10及30-60公分深者，因藥效未能全部達到，尚有部份根瘤線蟲存在。對60-100公分深者，則全無效果。
(3) 300-600公升／公頃D-D係在43年9月及44年3月施用。44年4月在該等地種植黃麻及鐘麻，生育良好，則D-D藥效甚爲明顯。俟至45年4月，再種植鐘麻及黃麻時，D-D藥效已全失。D-D各處理區與對照區之間，罹病指數均極接近，株高亦無何差別。因此，300-600公升／公頃D-D的藥效僅能供1期作（半年）之防病，不能維持1年以上。

並列摘要

This paper gives the experimental results on the effect of D-D mixture on the occurrence of root knot of kenaf. The present experiments were chiefly conducted in Tainan Experiment Station of the Taiwan AgriculturalResearch Institute Formosa, China during the Year 1956.
(1) Effect of different depths of injection on the occurrence of the nematodes was thoroughly studied. Amongst different depths of injection so far made, namely, 5, 10, 15, 20 and 25 cm, the injection made at 15 cm seems to be superior to that of others.
(2) Experimental results also indicated that soil depth had an important bearing on the nematocidal effect of D-D mixture studied. If the injection was made at 15 cm depth at the dosage of 500 liters per hectare, the nematodes inhabiting within 10 to 30 cm depth could be successfully eliminated. While the effect was markedly reduced at 0-10 and 30-60 cm depth, resp., and no appreciable difference in the nematodal population between the treated and untreated below 60 to 100 cm was noticed.
(3) In order to demonstrate the residual effect, in April, 1956 both kenaf and jute were seeded at the experimental plots where D-D mixture had been applied as early as Sept., 1954 and March, 1955, resp., at the rates of 300, 400, 500 and 600 liters per hectare. Subsequent results revealed that between the treated and untreated there was no substantial difference in both the height of plants and disease index observed. From the above-indicated fact it seems worthwhile to point out that this treatment may be effective only for six months or thereabout.