ASHS 2025 Conference

Huanglongbing (HLB), or citrus greening, has severely impacted citrus production in Florida, with no known cure currently available. Growers have increasingly adopted soil-focused management strategies, including cover cropping, to improve soil health and support tree resilience. In the Indian River District, where sandy soils with low fertility and organic matter prevail, the potential for cover crops to influence the soil microbiome remains underexplored. To investigate this, a three-year field trial was established in collaboration with a commercial grower and the University of Florida, IFAS, Indian River Research and Education Center, in Ft. Pierce. The trial included ‘Star Ruby’ grapefruit trees grafted on ‘US-942’, ‘Bearss’ lemon trees grafted on ‘Sour Orange’, and ‘OLL’ sweet orange trees grafted on ‘US-942’ rootstock. A randomized complete block design was used to compare conventional management (no cover crops) to a cover crop system, with species planted biannually and terminated at the end of each season. Soil microbiome composition and diversity were assessed seasonally through high-throughput sequencing, alongside measurements of soil nutrients, organic matter, moisture, and temperature. Early results suggest that the use of cover crops may influence soil microbial communities, with some differences observed between treatments over the three-year period. These include modest shifts in microbial diversity and structure, although the functional significance of these changes remains unclear. These findings suggest that cover crops may influence the soil microbiome in HLB-affected citrus groves, potentially contributing to improved soil conditions and offering a possible strategy to support long-term sustainability in southeast Florida citrus production systems.