• Korean Journal of Weed Science
• /
• v.30 no.3
• /
• pp.291-299
• /
• 2010

Cyhalofop-butyl and penoxsulam, known for respective acetyl CoA carboxylase (ACCase) and acetolactate synthase (ALS) inhibitor, have been widely using as a post-emergence foliar application for many years in wet-seeded rice field in Korea. Since 2009, control of Echinochloa oryzoides with cyhalofop-butyl and penoxsulam was no longer satisfactory. Greenhouse and experiment in rice field were conducted to confirm E. oryzoides resistance to ACCase and ALS inhibitors and to compare herbicide treatments for control of the resistant E. oryzoides to ACCase and ALS inhibitors. Three resistant E. oryzoides to ACCase and ALS inhibitors accessions were tested for levels of resistance to cyhalofop-butyl and penoxsulam, base on survival rate. Iksan and Kimje accessions were not any affected to the survival by treatment with recommended doses of two herbicides tested. Buan accession displayed an intermediate response of 62 and 72% survival at recommended doses of cyhalofop-butyl and penoxsulam, respectively. Survival rates to herbicides mixed with ACCase and ALS inhibitors at 3.5 leaf stage of E. oryzoides was over 80%. Benzobicyclon+fentrazamide+bensulfuron SC, benzobicyclon+mefenacet+bensulfuron SC, benzobicyclone +cafenstrole+pyrazosulfuron-ethyl GR controlled effectively by 2 leaf stage of resistant E. oryzoides to ACCase and ALS inhibitors. In the field experiment, single treatment of benzobicyclon+ fentrazamide+bensulfuron SC and benzobicyclon+mefenacet+bensulfuron SC failed to control E. oryzoides, but squential treatment of benzobicyclon+thiobencarb SE and benzobicyclon+ mefenacet+ bensulfuron SC controlled effectively it in rice infant seedling culture with machine. Our results suggest that resistant E. oryzoides to ACCase and ALS inhibitors had not developed multiple resistance to herbicides with different modes of action. In particular, cafenstrole, fentrazamide, mefenacet were effective control measures.

• Korean Journal of Weed Science
• /
• v.18 no.3
• /
• pp.246-256
• /
• 1998

The objective of this study was to investigate the cause of anthocyanin accumulation in the corn leaves treated with metsulfuron-methyl. The accumulation of anthocyanin and total sugar was increased with the time after metsulfuron-methyl application and with the greater herbicide concentration as well. The anthocyanin increase was alleviated by the combined treatment of DUMU or the tank-mixture treatment of metsulfuron-methyl, isoleucine and valine. Metsulfuron-methyl could not enhance the anthocyanin formation in the nonchlorophyllous tissue in which photosynthetic carbohydrate production was limited. Upon the exogenous supply of sucrose, however, the contents of anthocyanin was increased in the both chlorophyllous and nonchlorophyllous leaf segment of corn without the herbicide treatment. On the other hand, the herbicide itself did not influence Hill reaction in vitro and photosynthesis electron transport in vivo. The anthocyanin accumulation by metsulfitronmethyl did not occur in the corn mutants deficient in the structural gene of anthocyanin synthesis, but corns deficient in the regulatory gene had the anthocyanin accumulation only in R-r and r-r type. The above results suggest that the purple pigmentation in the corn leaves treated with metsulfuron-methyl is related to the accumulation of photosynthetic carbohydrate which can stimulate the. regulatory gene related to anthocyanin biosynthetic pathway.