ABSTRACT The increase in agricultural production is facing several challenges with future implications for food security and environmental protection. The aim of this study was to evaluate a remote sensing-based low-cost methodology for assessing the effects of dicamba and 2,4 Dichlorophenoxyacetic acid (2,4D) in a non-tolerant soybean crop. Here, we introduced the application of six vegetation indices (VI) derived from Unmanned Aerial Vehicle (UAV) based Red-Green-Blue (RGB) imagery contrasting with a conventional approach of visual injury criteria classification to estimate soybean plant injury and the effect on grain yield. The results demonstrated the feasibility of Modified Green-Red Vegetation Index (MGRVI) and Excess Green (ExG) strongly correlated with the effects of dicamba and 2,4D in soybean. These VIs discriminated plant injury caused by dicamba and 2,4D up to 5% of the recommended dose. The Lethal Dose 50 (LD50) considering the effect on grain yield was around 13% (72.80 g a.e. ha−1), 55% (552.75 g a.e. ha−1) and 48% (482.40 g a.e. ha−1) for dicamba; 2,4D dimethylamine (DMA) and 2,4D choline (CHO) of the recommended dose, respectively. This study revealed noteworthy limitations for the RGB indices to discriminate between the effects of different formulations of the same herbicide, as for 2,4D DMA and 2,4D CHO. With expectations for the introduction of new genetic soybean events and alongside new synthetic auxin compounds, our results pointed out that the proposed methodology can lead to a protocol for identifying and estimating the damage to the off-target movement from these outcoming herbicides on neighbourhood fields.

中文翻译：

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通过基于无人驾驶飞行器 (UAV) RGB 图像的植被指数评估麦草畏和 2,4 二氯苯氧乙酸 (2,4D) 对大豆的影响

摘要 农业生产的增长正面临着若干挑战，对未来的粮食安全和环境保护产生影响。本研究的目的是评估一种基于遥感的低成本方法，用于评估麦草畏和 2,4 二氯苯氧乙酸 (2,4D) 对非耐受大豆作物的影响。在这里，我们介绍了从基于无人驾驶飞行器 (UAV) 的红绿蓝 (RGB) 图像衍生的六个植被指数 (VI) 的应用，与视觉损伤标准分类的传统方法相比，以估计大豆植物损伤及其对植物的影响。粮食产量。结果表明，改良绿-红植被指数 (MGRVI) 和过量绿化 (ExG) 的可行性与麦草畏和 2,4D 对大豆的影响密切相关。这些 VI 区分了麦草畏和 2,4D 引起的植物损伤，最高可达推荐剂量的 5%。考虑到对谷物产量的影响，麦草畏的致死剂量 50 (LD50) 约为 13% (72.80 g ae ha-1)、55% (552.75 g ae ha-1) 和 48% (482.40 g ae ha-1)；分别为推荐剂量的 2,4D 二甲胺 (DMA) 和 2,4D 胆碱 (CHO)。这项研究揭示了 RGB 指数在区分相同除草剂不同配方的影响方面存在显着局限性，如 2,4D DMA 和 2,4D CHO。随着对引入新的大豆基因事件以及新的合成生长素化合物的期望，我们的结果指出，所提出的方法可以产生一个协议，用于识别和估计这些即将出现的除草剂对邻近田地的脱靶运动的损害。