SD38: A transdisciplinary research and management approach for laurel wilt: Current progress and future directions

Laurel wilt (LW), caused by the fungus Harringtonia lauricola (HL), is a deadly vascular disease affecting numerous hosts in the Lauraceae, including important forest species and avocado trees. Since its introduction into the U.S., HL has killed over 500 million trees. The fungal pathogen is spread by beetle-vectors, through root grafts, and human-mediated transport of infested wood. LW has spread rapidly and is now present in 12 states. It has been found as far west as eastern Texas and continues to spread towards major avocado-producing areas in California and Mexico. The broad geographic range of the susceptible hosts, in addition to the abundance and generalist habit of the beetle-vectors, has promoted the unprecedented rapid expansion of LW across ecosystems. The use of fungicides (propiconazole) and cultural practices (stumping and stump heat treatment) have not been successful in controlling outbreaks in commercial orchards. Currently, the only cost-effective management strategy is the timely removal of infected trees, which is limited by the early detection of the pathogen. Building on knowledge generated over a decade, our transdisciplinary team is exploring novel approaches for disease management, including early detection, searching for resistance/tolerance through high throughput screening of a wide array of avocado genotypes; and searching for sustainable biological control tools and new synthetic compounds. By exploring multiple approaches, from early and rapid pathogen detection to short and long-term pathogen and host management, we aim to develop and deploy efficient strategies that can be integrated into a sustainable program to mitigate the impact of the disease.