In planta testing of Antagonistic Fungal Endophytes against Harringtonia lauricola

Authors: TAIBI-BRIZ, KIARA - Florida International University; JAYACHANDRAN, KRISH - Florida International University; Nageswara Rao, Madhugiri; SHETTY, KATEEL - Florida International University

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 2/19/2025
Publication Date: 2/21/2025
Citation: Taibi-Briz, K., Jayachandran, K., Nageswara Rao, M., Shetty, K.G. 2025. In planta testing of Antagonistic Fungal Endophytes against Harringtonia lauricola. Meeting Abstract. 2025 Graduate Research Symposium, Department of Earh and Environment, Florida International University, Miami, Florida. February 21, 2025.

Interpretive Summary:

Technical Abstract: Laurel wilt is a vascular disease affecting avocado trees in South Florida. This disease is spread through an invasive insect vector, Xyleborus glabratus or ambrosia beetle and its fungal pathogen symbiont, Harringtonia lauricola. The ambrosia beetle bores into the bark of the avocado tree while simultaneously carrying the fungal pathogen in its mouth part. The fungal pathogen spreads within the galleries eliciting a stress response from the host tree to block water and nutrients from flowing in the xylem causing wilting. Control methods for the laurel wilt are limited to costly fungicide treatments that require reapplication every two to three years. In this study, fungal endophytes isolated from avocado bark samples were used to determine the in planta antagonistic potential against the fungal pathogen. In planta testing was conducted using a susceptible avocado variety, Brogdon x Waldin rootstock. The results showed no symptom development in plants that received stem inoculation of both endophyte and fungal pathogen compared to the pathogen inoculated plants. The endophytic isolates Tricoderma crissum and Tricoderma simmonsii were found to be capable of suppressing the symptom development caused by the laurel wilt fungal pathogen