In September, 2022 the Ministry of Agriculture, Land and Fisheries (MALF) is scheduled to commence a detection survey for Lethal Yellowing disease in Trinidad and Tobago. Lethal Yellowing is listed as a notifiable disease in Trinidad and Tobago because of the largescale economic impact it can have on the coconut industry. The disease is caused by a phytoplasma, which is carried by the leaf hopper – Haplaxius crudus. It spreads rapidly and can kill 90% of coconut trees within 3 – 18 months.
Ahead of the survey, CARDI and the International Trade Center (ITC) under the European Union (EU) /CARIFORUM supported, Alliances for Caribbean Coconuts II project, facilitated a sensitisation workshop, on the detection of Lethal Yellowing Disease for MALF’s staff. Facilitating the sessions, were Plant Pathologist, Dr. Wayne Myrie from the Coconut Industry Board, Jamaica and Dr. Brian Bahder, Assistant Professor from the University of Florida. CARDI Representative in Trinidad and Tobago, Fayaz Shah noted that these sessions were, “designed to improve the technical capacity of the Ministry’s staff, to effectively scout and identify the vector, identify symptoms and sample for the disease.”
During an in- field session Dr. Myrie noted some of the common disease symptoms are, premature nut fall, necrosis of the inflorescence, yellowing or browning of the leaves, and the classic telephone pole appearance of the trees as the disease progresses. However, he cautioned that drought related stress can mimic Lethal Yellowing symptoms and encouraged precise testing be done to confirm its presence. Staff were also trained in sampling of coconut trees, for polymerase chain reaction (PCR) analysis. PCR analysis of is one of the most common methods for phytoplasma detection and identification.
Meanwhile Dr. Bahder conducted in-field demonstrations, for scouting of leaf hoppers using a sputa. Ministry’s staff also received training on identifying the vector. Dr. Bahder noted that the adults feed on the underside of the leaf, and are easier to spot in the morning.
Pests and diseases are major hindrances to coconut production in the Caribbean, and CARDI and ITC continue to work with a network of experts to introduce integrated pest management strategies to keep pests populations below the economic threshold.