Tarbiat Modares University Journal of Crop Protection 2251-9041 11 4 2022 12 01 Grass weeds control in transplanted rice with Cyhalofop-butyl 433 443 1607 10.48311/jcp.2022.1607 EN Somayeh Tokasi Plant Protection Research Department, Guilan Agricultural and Natural Resources Research and Education Center, Agricultural Research, Education and Extension Organization (AREEO), Rasht, Iran. Morteza Nouralizadeh Otaghsara Plant Protection Research Department, Mazandaran Agricultural and Natural Resources Research and Education Center, Agricultural Research, Education and Extension Organization (AREEO), Sari, Iran. Journal Article <br> <span>This experiment was performed to determine the appropriate dose of Cyhalofop-butyl (CB) for controlling grass weeds in transplanted rice. CB at</span> <span>four doses, including 50, 100, 150, and 200 g ai/ha was investigated and compared with current herbicides in rice at recommended doses. The results showed that CB 100, 150, and 200 g ai/ha significantly reduced the density and dry matter of Echinochloa crusgalli (L.) P. Beauv. and Paspalum distichum L. over the weedy check; the minimum control efficacy of CB at these doses was 73.3 and 88.3% for E. crusgalli density and dry matter reduction, respectively, and for P. distichum, it was 80% for density and dry matter reduction. Applying CB at all doses (50- 200 g/ha) showed no crop injury symptoms on rice plants. The highest grain yield was obtained by hand weeding, CB 150 g ai/ha, and Tiobencarb treatments, with 5180, 5106, and 5051 Kg/ha, respectively. CB 200 g ai/ha was on par with CB 150 g ai/ha, and there was no significant variation between CB 100 and 200 g ai/ha in rice grain production. Finally, it was found that the application of CB 100 g ai/ha is an efficient grass weed control practice for improving the rice yield.</span><br> https://jcp.modares.ac.ir/article_1607_9597353e41e6957b5e7aa79214fcb256.pdf