Oxyfluorfen 및 bensulfuron-methyl의 處理時期에 따른 벼品種 및 主要 雜草種의 耐性反應

Response of rice cultivars and major weeds to different application time of oxyfluorfen and bensulfuron-methyl

Rice cultivars, Aichiasahi vs. Mushakdenti for oxyfluorfen and Chinsurah Boro II vs. IR 1846 for bensulfuron-methyl were experimented as the toterant vs. susceptible among other selected cultivars, respectively. The study was intended to know the difference in selectivity of both selected cultivars comparing with principal paddy weed species, and in relation with application time. -From the trial of oxyfluorfen by per-emergece soil application, ED₅₀ in rice cultivars indicate a highly significant tolerance to weed species, and rice cv. Aichiasahi showed higher level in ED₅₀ than that of cv. Mushakdanti. -From the trial of oxyfluorfen by post-emergence foliar application, Cypercus serotinus, Scirpus juncoides, Eleocharis kuroguwai and rice cv. Aichiasahi were recognized as rather tolerant than others. -From the trial of bensulfuron-methyl by pre-emergence soil application, rice cultivars showed more than 95% level in survival rate at 0.05kg ai/ha, however weed species were killed completely. Also the higher tolerance was detected from the tolerant cv. Chinsurah Boro Ⅱ comparing to cv. IR 1846. -From the trial of bensulfuron-methyl by post-emergence foliar application, no big difference in selectivity was evaluated between not only two varieties, and but also among rice and weed species.