Abstract
1. Chlorsulfuron (2-Chloro-N- [ (4-methoxy-6methyl-1, 3, 5-triazin-2yl) aminocarbonyl] benzenesulfonamide at 2g a.i./10a showed complete control on broadleaf weeds with preemergence treatment, but was not so effective on gramineious weeds and sedge. However, the chemical at 4 and 8g a, i./10a strongly inhibited the growth of Poa anua andCyperus iriarespectivety
2. No phytotoxicity was observed even at high rate of Chlorsulfuron onZoysia tenuifolicandAgrostis stronifera. Therefore, it was concluded that Chlorsulfuron was selectively safe on turf.
3. Test result in field was almost same as abovementioned result in greenhouse. Chlorulfuron at 2g a.i./10a provided excellent weed control on most broadleaf weeds, but, even at 8g a, i./10a it was not effective on crabgrass and barnyardgrass.
4. The chemical was applied on weeds grawn to the height of 10-30cm. As a result, Chlorsulfuron at 2-4g a.i./10a showed excellent weed control onTaraxacum officinale, Erigeron annusandErigeron philadelphicus. And at 8g a.i./10a it was effective onHydrocotyle sibthorpioidesandOxalis corniculatabut not so effective onPumex acetosellaandCayratia japonica.
5. Combination of Chlorsulfuron with Simazine, Atrazine or Siduron improved the efficacy of Chlorsulfuron on grass and Cyperus. The combination was useful for integrated weed control in truf.
6. Relative mobility of Chlorsulfuron in upland soil leached about 4-5 cm depth. The mobility was larger than that of Simazine and smaller than 2.4-D.
