The impacts of legume and non-legume cover crops on the performance of HLB-affected citrus trees

Cover crops are important for improving agroecosystems in both annual and perennial cropping systems. The decline in citrus productivity due to Huanglongbing (HLB) has become a significant challenge for citrus producers in Florida and worldwide. Cover crops (CCs) are known for enhancing soil health, but their effects on HLB-affected trees remain unclear. This study aimed to evaluate the impact of CCs treatments in mature HLB-affected citrus trees over three years. The research was conducted in two commercial orchards and assessed TCSA, leaf nutrient concentrations, fruit yield, and fruit quality in response to legume and non-legume CCs mixes. Results found no significant short-term improvements in these parameters, but significant interactions between CC treatments, sampling dates, and sites for TCSA suggest site-specific and temporal variability ascribed to cover crops. The severe impact of HLB on tree growth and productivity, combined with the mature age of the trees, likely masked the potential benefits of CCs. Long-term studies are necessary to fully understand the benefits of cover crops in perennial systems, as previous research has shown potential yield and quality improvements over extended periods. Future research should focus on longer evaluation periods, diverse CC species, and integrated management practices to enhance the sustainability and resilience of HLB-affected citrus groves.