Monitoring weed mechanical and chemical damage stress based on chlorophyll fluorescence imaging

Longzhe Quan; Keyong Chen; Tianbao Chen; Hailong Li; Wenchang Li; Tianyu Cheng; Fulin Xia; Zhaoxia Lou; Tianyu Geng; Deng Sun; Wei Jiang

doi:10.3389/fpls.2023.1188981

Monitoring weed mechanical and chemical damage stress based on chlorophyll fluorescence imaging

Front Plant Sci. 2023 May 15:14:1188981. doi: 10.3389/fpls.2023.1188981. eCollection 2023.

Authors

Affiliations

¹ College of Engineering, Anhui Agricultural University, Hefei, Anhui, China.
² College of Engineering, Northeast Agricultural University, Harbin, China.
³ College of Engineering, China Agricultural University, Beijing, China.

Abstract

Currently, mechanical and chemical damage is the main way to carry out weed control. The use of chlorophyll fluorescence (CF) technology to nondestructively monitor the stress physiological state of weeds is significant to reveal the damage mechanism of mechanical and chemical stresses as well as complex stresses. Under simulated real field environmental conditions, different species and leaf age weeds (Digitaria sanguinalis 2-5 leaf age, and Erigeron canadensis 5-10 leaf age) were subjected to experimental treatments for 1-7 days, and fluorescence parameters were measured every 24 h using a chlorophyll fluorometer. The aim of this study was to investigate the changes in CF parameters of different species of weeds (Digitaria sanguinalis, Erigeron canadensis) at their different stress sites under chemical, mechanical and their combined stresses. The results showed that when weeds (Digitaria sanguinalis and Erigeron canadensis) were chemically stressed in different parts, their leaf back parts were the most severely stressed after 7 days, with photosynthetic inhibition reaching R=75%. In contrast, mechanical stress differs from its changes, and after a period of its stress, each parameter recovers somewhat after 1 to 2 days of stress, with heavy mechanical stress R=11%. Complex stress had the most significant effect on CF parameters, mainly in the timing and efficiency of changes in Fv/Fm, Fq'/Fm', ETR, Rfd, NPQ and Y(NO), with R reaching 71%-73% after only 3-4 days of complex stress, and its changes in complex stress were basically consistent with the pattern of changes in its chemical stress. The results of the study will help to understand the effects of mechanical and chemical stresses and combined stresses on CF parameters of weeds and serve as a guide for efficient weed control operations and conducting weed control in the future.

Keywords: chemical stress; chlorophyll fluorescence; complex stress; mechanical stress; weeds.

Grants and funding

This work was supported by the National Natural Science Foundation of China under the project (No. 52075092,32271998) and Anhui Agricultural University Intelligent Agricultural Equipment Research Institute Project (No.jz214102).