EFFECT OF DIFFERENT HERBICIDES, DOSES AND SPRAY VOLUME IN THE CHEMICAL MANAGEMENT OF PEARL MILLET [PENNISETUM GLAUCUM (L. LEEK)]

ABSTRACT The objective of this work was to evaluate the efficacy of different herbicides applied in post-emergence in the desiccation of pearl millet with different doses and spray volumes. For the desiccation, doses at 0, 25, 50 and 100% of the herbicide glyphosate (1,440 g ha-1) were used in 3 formulations (Original Round up, Round up Transorb and Round up WG), paraquat + diuron (500 + 250 g ha-1) and glufosinate-ammonium (800 g ha-1). In all treatments, 2 spray volumes (200 and 400 l ha-1) were used, and there was 1 treatment (control) without the application of herbicides. The treatment effects were evaluated visually at 3, 7, 14, 21 and 28 days after application (DAA). At the end of the evaluations, the dry mass of the plants was determined. The field trial was carried out in randomized block design. At the end of the study, at 28 DAA, all treatments presented total control of plant pearl millet, regardless of the dose and spray volume, except the treatments with paraquat + diuron and glufosinate-ammonium at the lower dose (25%), in 2 spray volumes, which nevertheless showed good and very good control, these two herbicides presenting an effect of volume, in which the control was higher with the use of smaller volume.

摘要 本研究旨在评估不同除草剂以不同剂量与喷雾容量进行苗后喷施枯杀处理对珍珠粟的防除效果。试验共设置三类除草剂处理：其一为3种剂型的草甘膦（Glyphosate），以有效成分1440 g·ha⁻¹为基准剂量，设置0、25%、50%、100%四个剂量梯度，对应剂型分别为原版农达（Round up）、农达Transorb剂型及农达WG剂型；其二为百草枯+敌草隆混剂，用量分别为500 g·ha⁻¹与250 g·ha⁻¹；其三为草铵膦（Glufosinate-ammonium），用量为800 g·ha⁻¹。此外设置不施用除草剂的空白对照处理。所有处理均采用200 L·ha⁻¹与400 L·ha⁻¹两种喷雾容量。分别于施药后3、7、14、21、28天（Days After Application，简称DAA）开展目视防效评价，试验结束时测定植株干重。本田间试验采用随机区组设计。试验结果表明，于施药后28天（试验终点）时，除25%低剂量的百草枯+敌草隆与草铵膦处理（两种喷雾容量下）外，其余所有处理均实现了珍珠粟的完全防除；上述两个低剂量处理虽未达到完全防除，但仍表现出良好至极佳的防效，且这两种除草剂均存在喷雾容量效应：采用较小喷雾容量时的防效更为显著。