Spectral Evaluations for Developing Optical Methods of Huanglongbing (HLB) Detection in Citrus Orchards

摘要

Huanglongbing (HLB) is a devastating citrus disease that threatens the citrus industry in Florida. Several efforts are ongoing to control and contain this disease to protect the citrus industry. Among different approaches, detection of HLB is one of the critical steps in HLB management and control. At the Citrus Research and Education Center, Lake Alfred, we are working on multiple approaches to develop an effective and accurate mobile sensor system that can be used to detect HLB under field conditions. This research presents some of our ongoing work on HLB detection. A SVC HR-1024 spectroradiometer (350-2,500 nm) and a portable InfraSpec VFA-IR spectrometer (5,150-10,720 nm) were used to collect data from the healthy and HLB-infected citrus leavesto evaluate the applicability of the optical sensors. The reflectance data were collected in the visible, near-infrared, and mid-infrared regions of the electromagnetic spectra. The reflectance data were analyzed using statistical methods to classify HLB-infected citrus leaves from that of healthy ones. Preliminary results showed the potential of these methods in detecting HLB-infected citrus leaves with good accuracy.