Author
Huang, Yanbo | |
Thomson, Steven | |
Molin, William | |
Reddy, Krishna | |
YAO, HAIBO - Mississippi State University |
Submitted to: ASABE Annual International Meeting
Publication Type: Proceedings Publication Acceptance Date: 8/6/2011 Publication Date: 8/8/2011 Citation: Huang, Y., Thomson, S.J., Molin, W.T., Reddy, K.N., Yao, H. 2011. Detection of plant injury from application of non-selective herbicide by measurement of chlorophyll reflectance and fluorescene. American Society of Agricultural and Biological Engineers (ASABE) Annual International Meeting, St. Joseph, MI, paper No 1111330, pp. 7. Interpretive Summary: Early detection of crop injury due to off-target drift of herbicide is critical in crop production. Subtle changes in canopy reflectance could provide useful information to detect the crop stress early. This study has been conducted in a greenhouse to evaluate plant chlorophyll reflectance and fluorescence measurements for detection of crop injury caused by glyphosate spray. The results of the study indicated that the plant chlorophyll reflectance measurement could be useful to detect crop stress 24 hours after the herbicide treatment and the plant chlorophyll fluorescence measurement started to detect crop stress 48 hours after treatment. The study provides useful information between plant optical response and crop injury from non-selective herbicide. Technical Abstract: Subtle changes in canopy reflectance could present useful information to detect the onset of crop stress. This study was conducted in a greenhouse to evaluate a portable spectroradiometer and a portable chlorophyll fluorometer for the detection of crop injury caused by glyphosate spray. In this study, several plants of a non-glyphosate resistant soybean (Glycine max) variety were subjected to spray from a pneumatic track sprayer operated in a spray chamber. Four plants received a rate of 0.86 kg ae/ha glyphosate and four plants received 0.086 kg ae/ha. Additional four non sprayed plants were used as controls. After the spray treatment, the chlorophyll reflectance of the plants was measured with the spectroradiometer at 4, 24, 48, and 72 hours to determine the plant response to herbicide. Simultaneously, with the reflectance measurement, the portable chlorophyll fluorometer was used to measure fluorescence induction kinetics of the crop under stress. Results of the study indicated that the plant chlorophyll reflectance measurement could provide useful information on crop stress 24 hours after treatment and that plant chlorophyll fluorescence measurement could provide information on crop stress 48 hours after the treatment. |