Sumatran Fleabane Control using Glyphosate in Association with Halauxifen-Methyl Formulations

ABSTRACT: The effectiveness of a new product has a great importance to weed control, especially those that are difficult to control or resistant to, such as the sumatran fleabane (Conyza sumatrensis). The objective of this research was to evaluate the control of C. sumatrensis at different growth stages, using halauxifen-methyl in combination with other herbicides. The experimental design used was a randomized blocks in a 3x10 factorial scheme, with four replications. The plants of C. sumatrensis were evaluated at different growth: stage 1: plants with 8 leaves; Stage 2: plants with 19 leaves and stage 3: plants with 45 leaves fully expanded. The herbicides used were the association of glyphosate with the herbicides 2,4-D at 806, 943 and 1,209 g a.e. ha-1, halauxifen-methyl + diclosulam at 5.06 g a.e. ha-1 + 25.52 g a.i. ha-1 and 6.32 g a.e. ha-1 + 31.87 g a.i. ha-1, halauxifen-methyl + 2,4-D at 5.00 + 783 g a.e. ha-1 and 6,0 + 940 g a.e. ha-1 and halauxifen-methyl at 5.0 and 6.0 g a.e. ha-1 and untreated, totaling 10 treatments. The herbicides demonstrated satisfactory control of the plants in Stage 1 at 50 DAA, with the exception of the glyphosate + 2,4-D treatment at the lowest rate. However for Stages 2 and 3 the halauxifen-methyl + diclosulam in both rates, provided superior controls in relation to the other treatments. The control of sumatran fleabane was facilitated when their management occurs in the early stages of development, however independent of the development stage, the best controls obtained were with the treatment containing glyphosate + halauxifen-methyl + diclosulam at 1,440 g a.e. ha-1 + 6.32 g a.e. ha-1 + 31.87 g a.i. ha-1. Thus, combinations of herbicides containing halauxifen-methyl are another option to control C. sumatrensis in agricultural systems.

摘要：新型除草剂产品的防效对杂草防治意义重大，针对难防除或已产生抗药性的杂草尤为如此，例如苏门白酒草（Conyza sumatrensis）。本研究旨在评价氯氟吡啶酯（halauxifen-methyl）与其他除草剂复配时，对不同生育期苏门白酒草的防除效果。试验采用3×10因子设计的随机区组设计，设置4次重复。试验分别在3个生育期对苏门白酒草开展评价：生育期1：植株具8片叶片；生育期2：植株具19片叶片；生育期3：植株具45片完全展开的叶片。供试除草剂组合如下：草甘膦与2,4-滴按806、943、1209 g酸当量/公顷（g a.e. ha⁻¹）复配；氯氟吡啶酯+双氯磺草胺（diclosulam）分别按5.06 g a.e. ha⁻¹ + 25.52 g有效成分/公顷（g a.i. ha⁻¹）、6.32 g a.e. ha⁻¹ + 31.87 g a.i. ha⁻¹复配；氯氟吡啶酯+2,4-滴分别按5.00 + 783 g a.e. ha⁻¹、6.0 + 940 g a.e. ha⁻¹复配；氯氟吡啶酯单剂按5.0、6.0 g a.e. ha⁻¹施用，以及不施药空白对照，共计10个处理。
施药后50天（DAA）的调查结果显示，除最低剂量的草甘膦+2,4-滴处理外，其余供试药剂对生育期1的苏门白酒草均表现出优异的防除效果。但针对生育期2和3的植株，两种剂量的氯氟吡啶酯+双氯磺草胺复配处理的防效均显著优于其他所有处理。在杂草生育早期开展防治可提升苏门白酒草的防除效率，但无论处于何种生育期，最优防效均来自草甘膦+氯氟吡啶酯+双氯磺草胺按1440 g a.e. ha⁻¹ + 6.32 g a.e. ha⁻¹ + 31.87 g a.i. ha⁻¹的复配方案。综上，含氯氟吡啶酯的除草剂复配组合可作为农业生产系统中防治苏门白酒草的可行方案。