Grove-First: A Generalizable Framework to Evaluate Translational Solutions to Citrus Greening and Other Perennial Crop Diseases

Citrus greening disease, also known as huanglongbing (HLB), is the most serious vector-borne bacterial disease of citrus worldwide and an emblematic case of perennial crop decline due to insect vector-borne disease. There is an immediate global need to provide the citrus industry with relief from HLB and a return to profitable citrus production. Discovery of HLB treatments typically involve various laboratory-based assays, which then advance to greenhouse and eventually field testing in a workflow that takes multiple years. We present a field-forward experimental framework, "Grove-First", that reverses the traditional laboratory-to-field pipeline by prioritizing outcome-based screening. Grove-First rapidly screens and validates treatments with regulatory-friendly profiles in commercial citrus groves using trunk injection to select treatments that improve tree health and fruit yield over the course of a single growing season. The Grove-First framework represents a generalizable systems approach for translational agricultural research, applicable to perennial crops where disease impact, long development timelines, and real-world variability demand in-field, outcome-based screening. Using this framework, we identified candidate treatments with effects comparable to or better than the standard oxytetracycline (OTC) on visual tree-health and/or yield indices in an initial screen of HLB-positive 8-year-old Valencia sweet orange trees. Expanded trials in commercial citrus groves allowed us to validate the initial screening results at other locations and in other citrus varieties. Grove-First rapidly accelerated the identification and large-scale field testing of HLB therapies, some of which are available for growers to use immediately and others that require further field testing and/or regulatory actions.