• Korean Journal of Weed Science
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• v.5 no.2
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• pp.155-163
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• 1985

Three pyrazole-herbicides, pyrazolate, pyrazoxyfene and benzophenap, were evaluated for their interaction in controlling barnyardgrass (Echinochloa crusgalli) with two chloroacetamide-herbicides, butachlor and pretilachlor. Percent inhibition of barnyardgrass growth by pyrazolate, pyrazoxyfene, and benzophenap was 44%, 64%, and 0%, respectively, when each was applied at the 1.5 leaf-stage of barnyardgrass at a rate of 3㎏ ai per ㏊ as single treatment, and the benzophenap showed 60% inhibition when it was applied at the coleoptile stage. While the lowest rate controlling the 1.5 leaf-stage barnyardgrasses by 98 to 100% of the butachlor and pretilachlor was 1.5㎏ and 200g per ㏊, respectively. All of the combinations of pyrazolate with butachlor, pyrazoxyfene with pretilachlor, and benzophenap with butachlor have shown synergistic interaction in controlling barnyardgrass on the Chisaka's isobole of 90% growth inhibition as well as on the Colby`s interaction efficacy data; synergism indices were 2.44, 1.62 and 1.52 in order. The dose combinations shown the maximal synergism were 1870g of pyrazolate with 140g of butachlor (1:0.075), 33008 of pyrazoxyfene with 338 of pretilachlor (1:0.01), and 3350g of benzophenap with 520g of butachlor (1:0.15) on the ai/㏊ basis.

• Korean Journal of Weed Science
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• v.4 no.2
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• pp.169-178
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• 1984

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.