Department of Mathematics and Statistics, California State University, Monterey Bay, Seaside, California, United States of America.
Department of Plant Sciences, University of California, Davis, Salinas, California, United States of America.
PLoS One. 2021 Mar 15;16(3):e0248592. doi: 10.1371/journal.pone.0248592. eCollection 2021.
Image analysis is a useful technique to evaluate the efficacy of a treatment for weed control. In this study, we address two practical challenges in the image analysis. First, it is challenging to accurately quantify the efficacy of a treatment when an entire experimental unit is not affected by the treatment. Second, RGB codes, which can be used to identify weed growth in the image analysis, may not be stable due to various surrounding factors, human errors, and unknown reasons. To address the former challenge, the technique of image segmentation is considered. To address the latter challenge, the proportion of weed area is adjusted under a beta regression model. The beta regression is a useful statistical method when the outcome variable (proportion) ranges between zero and one. In this study, we attempt to accurately evaluate the efficacy of a 35% hydrogen peroxide (HP). The image segmentation was applied to separate two zones, where the HP was directly applied (gray zone) and its surroundings (nongray zone). The weed growth was monitored for five days after the treatment, and the beta regression was implemented to compare the weed growth between the gray zone and the control group and between the nongray zone and the control group. The estimated treatment effect was substantially different after the implementation of image segmentation and the adjustment of green area.
图像分析是评估杂草防治处理效果的有用技术。在这项研究中，我们解决了图像分析中的两个实际挑战。首先，当整个实验单位不受处理影响时，准确量化处理效果具有挑战性。其次，由于各种环境因素、人为错误和未知原因，可用于识别图像分析中杂草生长的 RGB 代码可能不稳定。为了解决前者的挑战，考虑使用图像分割技术。为了解决后者的挑战，在贝塔回归模型下调整杂草面积的比例。当因变量（比例）在 0 到 1 之间时，贝塔回归是一种有用的统计方法。在这项研究中，我们试图准确评估 35%过氧化氢（HP）的功效。应用图像分割将两个区域分开，HP 直接应用的区域（灰色区域）及其周围区域（非灰色区域）。处理后五天监测杂草生长情况，并实施贝塔回归比较灰色区域和对照组、非灰色区域和对照组之间的杂草生长情况。实施图像分割和绿色面积调整后，估计的治疗效果有很大差异。
