ASABE Technical Library - Abstract

Abstract. The Florida avocado industry is the state’s second-largest fruit industry (behind citrus) with 30,700 tons of avocado harvested in 2013 and a value of the production of $35 million at the wholesale level. Laurel wilt (LW) is a vascular disease that has recently spread rapidly along the southeastern seaboard of the United States. LW disease has the potential to quickly destroy avocado production in Florida causing losses of $27 to 54 million if a reliable control strategy is not found. In this study, the spatial requirements necessary to discriminate LW from healthy trees were evaluated. A MCA-6 Tetracam camera was used to take images in an LW infected avocado orchard with trees at different stages of LW development: early, intermediate, and late at three helicopter flying altitudes (180, 250 and 300 m). The most effective flight altitude, as well as vegetation indices were selected by performing analysis of variance (ANOVA) and M-statistic to quantify the separability between classes. These results confirmed the potential of classifying LW at different stages of development, even trees in the early stage of disease development with minimal symptoms, using multispectral aerial images captured by a MCA-6 camera.