Glyphosate resistance in junglerice (<i>Echinochloa colona</i>) and alternative herbicide options for its effective control

Abstract Control of glyphosate-resistant (GR) junglerice is a challenging task in eastern Australia. There limited information on the efficacy and reliability alternate herbicides for GR populations junglerice, especially when targeting large plants temperatures are high. A series experiments were conducted to confirm level glyphosate resistance three evaluate control populations. The LD 50 B17/7, B17/34, B17/35 was found be 298, 2,260, 1,715 g ae ha –1 , respectively, suggesting that B17/34 highly resistant glyphosate. Glyphosate reduced at high-temperature (35 C day/25 night) compared with low-temperature conditions (25 day/15 night), susceptible may also if sprayed under hot conditions. Preemergence dimethenamid-P (1,000 ai ) pendimethalin (1,500 provided 100% (B17/34 17/35). Postemergence herbicides, such as clethodim (60 or 90 ), glufosinate (750 haloxyfop (52 78 paraquat (400 600 applied four-leaf stage For larger (eight-leaf stage), postemergence applications greater weed than clethodim, glufosinate, haloxyfop. mixture either poor application alone. Efficacy decreased sequential spray after application. This study identified alternative herbicide options can used rotation programs sustainable management.