Weed Control with Herbicides in Protected Semi - irrigated Rice Seedbed

보온절충(保溫折衷) 못자리에 있어서 제초제(除草劑)에 의한 잡초방제(雜草防除)에 관한 연구(硏究)

This experiment was conducted to find out selective herbicides which are safe to the rice seedlings and to provide effective weed control method in protected semi-irrigated rice seedbed. There was no crop injury in rice with benzophenap [2-(4-2, 4-dichloro-3-methylbenzoyl)-1, 3-dimethyl-pyrazol-5-yl-oxy)-4'-methyl acetophenone] (240g), pyrazoxyfene [1,3-dimethyl-4-(2,4-dichlorobenzoyl)-Sphenacyloxy pyrazole] (200g), chlormethoxynil [2,4-dichlorophenyl-4-nitro-3-methoxyphenyl ether] (180g), dimepiperate [S-(1-methyl-1-phenethyl)-piperidine-l-carbathioate] (210g), dimepiperate + probenazol [3-allyloxy-1,2-benzisothiazol-1,1-dioxide] (210 + 120g) mixture and dimepiperate + probenazol + molinate [S-ethyl-N,N-hexamethylene-thiol-carbamate] (120 + 120 + 120g) mixture at times of application studied. Butachlor [2-chloro-2',6'-diethyl-N-buthoxymethyl acetanilide] + pyrazolate [4-(2,4-dichlorbenzoyl)-1,3dimethyl-pyrazol-5-yl-p-toluene-sulfonate] (70 + 120g) mixture and butachlor + chlormethoxynil (60 + 120g) mixture caused root length to shorten and root viability to decrease. However, the crop injury was recovered at 25 days after seeding. Benzophenap, pyraxoxyfene and butachlor + pyrazolate mixture were effective for weed control when applied at 2 days before seeding. Chlormethoxynil and butachlor + chlormethoxynil mixture was very effective for controlling annual weed. Dimepiperate, dimepiperate + probenazol mixture and dimepiperate + probenazol + molinate mixture did not control most weeds except for Echinochloa crus-galli (L.) Beauv.

보온절충(保溫折衷)못자리에서 유망시(有望視)되는 제초제(除草劑) 8종(種)에 대(對)하여 수축(收縮)의 약해(藥害) 및 제초효과(除草效果)를 검토(檢討)하였다. 1. Benzophenap(240g) 및 pyrazoxyfene(200g) 등(等)은 초기약해(初期藥害)가 인정(認定)되지 아니했으며, 제초효과(除草效果)도 만족(滿足)스러웠다. 2. Dimepiperate(210g) 단제(單劑), dimepiperate + probenazol(210+120g) 합제(合劑) 및 dimepiperate + molinate + probenazol(120+120+120g) 합제(合劑) 등(等)은 초기약해(初期藥害)가 없었으며 제초효과(除草效果)에 있어서 피에 대(對)하여는 우수하였으나, 그 이외(以外)의 공시초종(供試草種)은 저조(低調)한 살초효과(殺草效果)를 나타냈다. 3. Butachlor + pyrazolate(70+120g) 및 butachlor + chlormethoxynil(60+120g) 등(等)의 합제(合劑)는 초기약해(初期藥害)가 초기유묘(初期幼苗)와 근신장(根伸長)을 약간 저해(沮害)하는 현상(現象)을 보였으나 경시적(經時的)으로는 회복(回復)되었으며, 제초효과(除草效果)는 우수하였으나 butachlor + chlormethoxynil 합제(合劑)는 공시다년생잡초(供試多年生雜草)에 대(對)하여는 만족(滿足)스럽지 못하였다. 4. Chlormethoxynil(180g)은 초기약해(初期藥害)가 없었으며 공시(供試)한 일년생잡초(一年生雜草)에 대(對)하여 우수한 제초효과(除草效果)를 나타냈다. 5. 엽록소함량(葉綠素含量)이 있었으며 그 이외(以外)의 처리구(處理區)는 조사시기(調査時期)에 관계(關係)없이 유의성(有意性)이 없었다. 6. 근활력(根活力)은 butachlor + pyrazolate(70+120g) 및 butachlor + chlormethoxynil(60 + 120g)등(等)의 합제구(合劑區)에서 약종후(藥種後) 12일(日)에 유의성(有意性)이 있었으나 경시적(經時的)으로 회복(回復)되었으며 그 이외(以外)의 처리구(處理區)는 조사시간(調査時期)에 관계(關係)없이 유의성(有意性)이 없었다.