Objective 2. Determine the effect of antimicrobials on Las transmission.
Objective 2.2 Hypothesis: ACP will be less capable of transmitting CLas after feeding on antimicrobials because trees treated with antimicrobials are more likely to have lower CLas titers for acquisition.
Eight-year old CLas-infected citrus trees have received three foliar applications (May-July) of streptomycin, oxytetracycline (Treatments), or no antimicrobials (Control). Ten CLas-free insects per plant from a laboratory colony were caged on young leaves (flush) of treatment and control trees to analyze ACP survival and CLas-acquisition in ACP P1 and F1 progeny. Acquisition from five individual individual trees per replicate was evaluated. ACP survival and CLas-acquisition were repeated in June and July. During the first trial, ACP P1 adults were collected on the 26th of June. Approximately two weeks later, five to ten ACP adults corresponding to the F1 progeny were collected. The second trial began on July using the same conditions previously described, ACP P1 adults exposed to CLas-infected trees were collected on the 15th of July and its F1 progeny was collected on 22nd of July; ACP adults were collected individually in microcentrifuge tubes containing 1 mL of 80% ethanol and then stored at -20°C for subsequent CLas detection using real-time PCR. Concurrently, the titer of CLas had been monitored at the same time-points using three leaves per tree to determine the CLas-infection rate. The third trial is scheduled to begin in September. ACP from the first two trials are currently being processed to quantify acquisition.