Department of Plant Production, School of Agricultural and Veterinarian Sciences, São Paulo State University (UNESP), Jaboticabal, 14884-900, Brazil.
Sci Rep. 2021 May 10;11(1):9886. doi: 10.1038/s41598-021-89382-2.
The weeds are important in agricultural and livestock areas because these plants can cause several damages, especially in the yield. The herbicide pulverization for weed control is the most used, but the efficiency of the control can be dependent the several factors, for example, the correct chose the herbicide and the mixture or not with adjuvant. This study aimed to evaluate the contact angle of herbicide solution droplets associated with adjuvant when deposited on the leaf surface of different weed species and their relationship with chemical control. For the contact angle experiment, the design was completely randomized, with four repetitions, while for the control experiment, a randomized block design was used, both experiments were arranged in a factorial (4 × 2 + 1) design. Factor A corresponded to four spray solutions containing the herbicide no addition of adjuvants and herbicide associated with adjuvants (vegetable oil, mineral oil, and lecithin), factor B to two herbicide dosages, and additional treatment corresponded to water. The contact angle was determined in six weed species: Crotalaria incana, Lantana camara, Ipomoea grandifolia, Asclepias curassavica, Sida obtusifolia, and Ricinus communis, on the adaxial and abaxial surface of each species, and an artificial surface. For the weed control experiment was used two weed species: C. incana and L. camara. The multivariate analysis allowed the understanding of the behavior of the contact angle of the different groups on the natural and artificial surfaces, due to the formation of factors. For all plants, except for the abaxial surface of I. grandifolia and the adaxial surface of A. curassavica, the association of herbicide and adjuvants reduced contact angle on the surfaces. The chemical control resulted in an indirect relation with contact angle, where smaller contact angles of the herbicide solution resulted in a higher percentage of plant intoxication. Therefore, for this situation, it is recommended to use the herbicide aminopyralid + fluroxypir associated with lecithin.
杂草在农业和畜牧业地区很重要，因为它们会造成多种损害，尤其是在产量方面。杂草控制中最常用的方法是喷洒除草剂，但控制效果可能取决于几个因素，例如正确选择除草剂以及是否与助剂混合。本研究旨在评估与助剂混合的除草剂溶液液滴在不同杂草物种叶片表面的接触角及其与化学控制的关系。在接触角实验中，设计采用完全随机化，设有四个重复，而在化学控制实验中，则采用随机区组设计，这两个实验均以（4×2+1）析因设计安排。因子 A 对应于四种喷雾溶液，分别为不含助剂的除草剂溶液和含助剂（植物油、矿物油和卵磷脂）的除草剂溶液；因子 B 对应于两种除草剂剂量，而附加处理则对应于水。接触角在六种杂草物种（Crotalaria incana、Lantana camara、Ipomoea grandifolia、Asclepias curassavica、Sida obtusifolia 和 Ricinus communis）的叶面和叶背以及人工表面上进行测定。在杂草控制实验中，使用了两种杂草物种（C. incana 和 L. camara）。多元分析允许理解不同组在自然和人工表面上的接触角行为，因为这些因素会形成接触角。除了 I. grandifolia 的叶背和 A. curassavica 的叶面外，所有植物的除草剂与助剂混合均会降低表面的接触角。化学控制与接触角呈间接关系，除草剂溶液的接触角越小，植物中毒的百分比越高。因此，在这种情况下，建议使用含有助剂卵磷脂的除草剂 Aminopyralid + Fluroxypir。
