Effects of Varietal Type and Crop Season on the Performance of Some Granular Herbicides in Transplanted Rice

水稻品種與期作對若干水田粒狀除草劑藥效之影響

張萬來(W. L. Chang)

《中華農業研究》 20卷1期 (1971/03) Pp. 44-56

https://doi.org/10.29951/JARC.197103.0004

摘要

本文係報告嘉義農業試驗分所與國際稻米研究所合作，於民國59年第1期作及第2期作與辦水稻品種與期作對若干水田粒狀除草劑藥效之影響試驗所得結果。鴨舌草與球花蒿草爲試驗田之主要雜草，惟水秤之密度極低。日本型品種嘉農242號試區之雜草數目較印度型品種臺中在來1號者爲多，而第2期作之雜草亦多於第1期作。供試之粒狀除草劑均具良好之治草效果，除草劑冶草效果之品種間差異在生育初期並不明顯，惟在幼穗分化期則可看出明顯差異。即同一除草劑在嘉農242號試區之治草效果稍劣於臺中在來1號。除草劑之治草效果受期作之影響甚微。
2,4-D IPE, 2,4-D EE與TCE-Styrene/24-D IPE等粒劑對水稻最具藥害，MCPCA, EPTC/2,4-D IPE與CP 53619/2,4-D BE等粒劑次之，而CP 53619與Saturn對水稻則未具明顯藥害。臺中在來1號在生育初期似較嘉農242號易受藥害，惟前者復原情形顯較後者爲優，故在幼穗分化期嘉農242號反較臺中在來1號較具藥害。除草劑對水稻之藥害第一期作顯較第二期作嚴重。
供試除草劑中僅以Saturn在插秧後4天施用之處理，產量超過人工除草處理。施用除草劑而減產之程度，嘉農242號較臺中在來1號爲大，而第1期作則大於第2期作。

並列摘要

The effects of varietal type and crop season on the performance of some granular herbicides in transplanted rice evaluated at the Chiayi Agricultural Experiment Station, Chiayi, Taiwan, in the first and second crops of 1970 are reportd.
The major weeds of the experimental plots were Monochoria vaginalis and Cyperus difformis but Echinochina crusglli occupied only a small fraction of the total weed population. The number of weeds in the plots of Chianung 242 was more than that of Taichung native 1 while the growth of weeds in the second crop was better than that of the first crop.
Granular herbicides tested in this experiment generally provided satisfactory control of weeds. Weed control effect of herbicide treatments varied slightly with varietal type in the early stage of rice growth but the control of weeds in the plots of Taichung native 1 appeared better than that of Chianung 242 when it was rated at panicle initiation stage. Most herbicides gave similar control of weed in both crop seasons.
Granular 2,4-D IPE, 2,4-D EE, and TCE-styrene/2,4-D IPE were highly toxic to rice which were followed by MCPCA, EPTC/2.4-D IPE, and CP 53619/2,4-D BE while CP 53619 and Saturn showed very slight or no phytotoxicity to rice. Rice seedling of Taichung native 1 appeared to be more sensitive to chemical injury than Chianung 242 but former variety recovered more quickly and the toxicity ratings were smaller than those of the latter variety when they were recorded at panicle initiation stage. Phytotoxicity of herbicides was more pronounced in the first crop than in the second one
Among herbicides tested, only Saturn applied at 4 days after transplanting outyielded hand weeding, although several other gave rice yield much higher than that of unweeded treatment. Chianung 242 suffered greater reduction of yield than Taichung native 1 while herbicide treatments caused more reduction of yield in the first crop than in the second one. The decrease in grain yield was associated with the reduction in the number of panicles per hill.