Inversion of Chlorophyll and Water Content of Hami Melon Leaves Based on Spectrophotometry on Study
LI Long-jie1, SHI Yong1, 2, GUO Jun-xian1, 2*
1. College of Electrical and Mechanical Engineering, Xinjiang Agricultural University, Urumqi 830052, China
2. Xinjiang Key Laboratory of Intelligent Agricultural Equipment, Urumqi 830052, China
Abstract:In order to predict the water content and chlorophyll content of cantaloupe leaves quickly and accurately and improve the accurate management level of Cantaloupe crops, the leaves of cantaloupe in three different growth stages, namely the growing stage, the flowering stage, and the fruiting stage, were selected as experimental research objects by using the spectrophotometry technology. The correlation changes of leaf temperature, leaf water content, and chlorophyll content with LAB eigenvalues of color space were studied in three different collection periods: 9:00—10:00, 14:00—15:00, and 20:00—21:00, respectively. The least square method (LS) was used to preprocess the changes in temperature, water content, chlorophyll content, and color eigenvalues of different samples, and the eigenvalues with the best fit were selected for regression analysis and prediction model verification. The results showed that① Leaf temperature, leaf water content, and chlorophyll content had different color eigenvalues under different parameters. ② For leaves with 84%~93% moisture content, leaf temperature, and chlorophyll content were negatively correlated with leaf moisture content. ③ the chlorophyll content and leaf water content and color space LAB, there is a linear correlation. As the leaf water content -rises, L is on the rise, and the color becomes shallow gradually with light green leaves; with the increase of chlorophyll, L has a downward trend, showing the leaf color gradually deepens with black-green, exists in all types of sample data, L B positive. ④ Through model prediction and evaluation, random forest (RF), partial least squares (PLS), support vector machine (SVM), and LASSO can be used to predict chlorophyll content effectively. Among the chlorophyll prediction models, RF had the best prediction performance, R2c=0.939, RMSEC=0.868 and MAE=0.686, R2p=0.915, RMSEP=1.194 and MAE=0.942. ⑤ Through model prediction and evaluation, RF, PLS, AdaBoost, and polynomial regression (POLYNOMIAL) can effectivelypredict leaf water contents. In the prediction model of leaf moisture content, the POLYNOMIAL prediction performance is the best, R2c=0.884, RMSEC=0.005 9 and MAE=0.005 2, R2p=0.920 and RMSEP=0.006 2 and MAE=0.005 7. The spectrophotometry method can effectively and rapidly determine leaf water and chlorophyll content, which is expected to provide an optional feasible method for nondestructive, rapid, and accurate determination of leaf water and chlorophyll content.
Key words:Hami melon; Chlorophyll; Water content; LAB; Model regression
李龙杰,史 勇,郭俊先. 基于分光测色反演哈密瓜叶片叶绿素与含水率研究[J]. 光谱学与光谱分析, 2024, 44(08): 2296-2302.
LI Long-jie, SHI Yong, GUO Jun-xian. Inversion of Chlorophyll and Water Content of Hami Melon Leaves Based on Spectrophotometry on Study. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2024, 44(08): 2296-2302.
[1] WANG Dong, SHEN Kai-cheng, FAN Ye-man, et al(王 东, 沈楷程, 范叶满, 等). Transactions of the Chinese Society for Agricultural Machinery(农业机械学报), 2022, 53(4): 192.
[2] GAN Hai-ming, YUE Xue-jun, HONG Tian-sheng, et al(甘海明, 岳学军, 洪添胜, 等). Journal of South China Agricultural University(华南农业大学学报), 2018, 39(3): 102.
[3] LI Yong-mei, WANG Hao, ZHAO Yong, et al(李永梅, 王 浩, 赵 勇, 等). Acta Agriculturae Zhejiangensis(浙江农业学报), 2022, 34(4): 781.
[4] LI Hong, ZHANG Kai, CHEN Chao, et al(李 红, 张 凯, 陈 超, 等). Transactions of the Chinese Society for Agricultural Machinery(农业机械学报), 2021, 52(2): 211.
[5] GAO Sheng, WANG Qiao-hua(高 升, 王巧华). Chinese Optics(中国光学), 2021, 14(3): 566.
[6] SUN Xu-dong, HAO Yong, ZHANG Guang-wei(孙旭东, 郝 勇, 张光伟). Journal of Chinese Agricultural Mechanization(中国农机化学报), 2015, 36(2): 150.
[7] JI Rong-hua, ZHENG Li-hua, DENG Xiao-lei, et al(冀荣华, 郑立华, 邓小蕾, 等). Transactions of the Chinese Society for Agricultural Machinery(农业机械学报), 2014, 45(8): 269.
[8] ZHANG Jun-yi, GAO De-hua, SONG Di, et al(张俊逸, 高德华, 宋 迪, 等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2022, 42(5): 1514.
[9] MA Chun-yan, WANG Yi-lin, ZHAI Li-ting, et al(马春艳, 王艺琳, 翟丽婷, 等). Transactions of the Chinese Society for Agricultural Machinery(农业机械学报), 2022, 53(6): 217.
[10] HE Gui-fang, WU Jian, PENG Jian, et al(何桂芳, 吴 见, 彭 建, 等). Journal of Northwest Forestry University(西北林学院学报), 2022, 37(1): 25.
[11] ZHANG Hui-chun, ZHANG Meng, BIAN Li-ming, et al(张慧春, 张 萌, 边黎明, 等). Transactions of the Chinese Society for Agricultural Machinery(农业机械学报): 2022, 53(4): 313.
[12] CHENG Li-zhen, ZHU Xi-cun, GAO Lu-lu, et al(程立真, 朱西存, 高璐璐, 等). Acta Horticulturae Sinica(园艺学报), 2017, 44(2): 381.