Herbicidal Phytotoxicity of Early Rice Seedlings as Affected by Cultural Practices - II. Effect of Endosperm, Transplanting Depth, and Time Chemical Application

재배조건(栽培條件)의 차이(差異)가 수도(水稻)어린묘(苗)의 제초제(除草劑) 약해발생(藥害發生)에 미치는 영향(影響) - II. 배유유무(胚乳有無), 이앙심도(移秧深度), 처리시기(處理時期)에 따른 약해반응(藥害反應)

Various herbicides were applied to the young rice seedling from which endosperm were removed and their effects were determined at 40 days after transplanting. Generally, growth was retarded, but the number of tillers was not effected. Application of bensulfuron and pretilachlor showed slight growth inhibition compared to dimepiperate and pyrazolate. Injury due to herbicide application was dependent on the transplanting depth. Injury was severe when pretilachlor and pyrazolate were applied to rice transplanted 0 and 4cm deep, respectively. However, bensulfuron showed much injury regardless of transplanting depths with the tendency of general growth retardation. Dimepiperate was fairly safe at all transplanting depths. The application of herbicides at 3 and 6 DAT showed higher injury than that at g and 12 DAT. The degree of injury was severe when pretilachlor and bensulfuron were applied.

배유(胚乳)의 유무차이(有無差異)에 따른 공시제초제(供試除草劑)에 대(對)한 약해반응결과(藥害反應結果) 배유유무(胚乳有無)에 따라 초장(草長), 분얼수(分蘖數) 및 건물중(乾物重)에 있어서 유의적(有意的)인 차이(差異)를 나타내었다. 즉 무배유묘(無胚乳苗)보다 유배유묘(有胚乳苗)의 약제내성(藥劑耐性)이 전반적(全般的)으로 높은 경향(傾向)이었다. 이앙심도차이(移秧深度差異)에 따른 약해유발정도(藥害誘發程度)에 있어서는 0cm의 극천식조건(極淺植條件)에서와 4cm의 심식조건(深植條件)에서 2cm의 심도(深度)에서 보다 약해(藥害)가 증대(增大)되었는데 특히 pretilachlor는 0cm 조건(條件)에서, pyrazolate는 4cm 조건(條件)에서 생육(生育)이 억제(抑制)되었으며 bensulfuronmethyl은 전반적(全般的) 으로 약해(藥害)가 유발(誘發)되었다. 처리시기(處理時期)에 따른 약해반응(藥害反應)에 있어서는 공시약제(供試藥劑) 모두에서 9 또는 12DAT 처리조건(處理條件)에서보다 초기처리시기(初期處理時期)인 3, 6DAT처리에서 약해(藥害)가 증대(增大)되었으며 특히 pretilachlor와 bensulfuron-methyl에서 생육저해현상(生育沮害現狀)이 심(甚)한 경향(傾向)이었다.