Location: Application Technology ResearchTitle: Hyperspectral evaluation of Venturia inaequalis management using the disease predictive model RIMpro in the northeastern U.S
|BRODERS, KIRK - Colorado State University|
Submitted to: Agricultural Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/1/2017
Publication Date: 12/28/2017
Citation: Wallhead, M.W., Zhu, H., Broders, K. 2017. Hyperspectral evaluation of Venturia inaequalis management using the disease predictive model RIMpro in the northeastern U.S. Agricultural Sciences. 8:1358-1371.
Interpretive Summary: The decision of whether or not and when to apply a fungicide for apple scab is not always obvious. Decision-support systems are tools that help growers to decide when to spray. Spectral reflectance data can be obtained through the use of a hyperspectral spectroradiometer and compliments visual assessments of plant diseases. Spectral reflectance data provides finer scale quantitative data than visual assessments alone. Vegetation indices, calculated from the spectral reflectance data, were used to evaluate the effectiveness of the decision support system RIMpro at managing apple scab. Several of the vegetation indices evaluated were confirmed to excel in the identification of apple scab. Apple leaves treated according to RIMpro had reflectance properties similar to conventionally treated leaves. Also, this study provided further evidence that potassium bicarbonate mixed with sulfur could be a suitable spray material for use in organic orchard operations or for those interested in using low-cost, low-hazard alternative spray materials as part of their integrated pest management program.
Technical Abstract: Use of hyperspectral spectroradiometers allows for information on different light bands to be captured, allowing for much easier identification of plant health status. Apple scab, caused by the ascomycete Venturia inaequalis, is globally the most important disease in the production of apples. RIMpro is a web-based decision support system for orchardists that has the capacity to improve optimal fungicide application for the control of apple scab and has the potential to reduce the number of applications and thereby reducing input expenses. The objective of this study was to complete a hyperspectral assessment of apple leaves in order to evaluate the spectral characteristics of trees sprayed according to forecasted infection events from the DDS. No significant differences in vegetation index means were observed between leaves treated conventionally and leaves treated according to the DSS. The results from this investigation confirmed the importance of having an effective spray program guided with DSSs such as RIMpro.