本研究探討除草劑施得圃(pendimethalin)膠囊懸著液(capsule suspension, CS)，在不同氣候環境下施用，對春、秋兩作毛豆田雜草之防除效果，及引起毛豆生育與產量之藥害評估，以提供安全有效之使用方法，作為田間應用之參考。於花蓮、雲林及屏東三處進行之試驗，發生在田面之一年生雜草，主要包括牛筋草、芒稷、再生稻、碎米莎草、馬齒莧、野莧及通泉草等。施得圃38.72% CS（2.5及3.5 L ha^(-1)）及34% EC(4.5 L ha^(-1))對雜草株數之抑制效果與不除草區有顯著差異，同時CS劑型亦較EC者為佳，有明顯殺死再生稻、野莧及通泉草之效果，對碎米莎草、馬齒莧及鱧腸亦有抑制，但在春作田有恢復生長現象。比較施得圃38.72% CS與34% EC兩種劑型間之雜草鮮重，雖有明顯差異，但相差程度較株數估算值為小。以施藥後35-40日，調查所得之38.72% CS（2.5及3.5 L ha^(-1)）、34% EC(4.5 L ha^(-1))及不除草區雜草株數與鮮重作相關性分析，顯示藥劑處理區田面發生之雜草單株鮮重介於3.8-5.8 g，多為陸續再生之小苗，不除草區則為整地後即長出之較大植株，單株重約為9.2 g。施得圃處理後對毛豆植株外觀形態、生育相關性狀等，均未觀察到有異常之藥害現象發生。對毛豆鮮莢產量之影響，於秋作田之藥劑處理區其產量均顯著高於不除草區，且與人工除草區無明顯差異。春作田則以人工除草區產量最高，施得圃不同劑型處理，雖以38.72% CS(3.5 L ha^(-1))之產量值較高，但各劑型間並無顯著差異。綜合藥效及藥害試驗結果，以施得圃38.72% CS以2.5或3.5 L ha^(-1)劑量噴施毛豆田，對雜草之防治效果均較34% EC(4.5 Lha^(-1))明顯為佳，且對毛豆植株之生育及鮮莢產量，亦未引起抑制及減產等藥害現象。

Field studies were conducted in 2001 and 2002 at three locations of Hualien, Yunlin and Pingtung to determine the effectiveness and safety of preemergence applications of pendimethalin 38.72% CS. Pendimethalin 38.72% CS treatments at 2.5 or 3.5 L/ha controlled volunteer rice, slender amaranth, and Japanese mazus 85 to100%. But Control of rice flatsedge, common purslane, and eclipta with pendimethalin 38.72% CS varied greatly between fall and spring cropping seasons. In general, fall applications of pendimethalin CS and pendimethalin EC provided greater weed control than spring application. Due to the regression curve of weed plant number and fresh weight, the biomass of per weed plant in pendimethalin treated plots was less than 50% of that of untreated plots. It did not appear any injury to soybean treated with tested pendimethalin in all experiments. To compare soybean yields, there was no significant difference between the two treatments of pendimethalin application and hand-weeded plots.