Tank Mixes and Premixes of Experimental and Labeled Insecticides for Control of Asian Citrus Psyllid and Citrus Leafminer on Oranges, Summer, 2014 *

ACP vectors the bacterium Candidatus Liberibacter asiaticus, causal organism of citrus greening disease or “Huanglongbing.” Feeding damage from CLM larvae facilitates the spread of citrus canker caused by Xanthomonas axonopodis pv. citri . Effective control measures are needed upon which to develop integrated management strategies against these pests and the associated diseases in Florida citrus. The experimental block in a commercial grove near LaBelle, Florida consisted of 7-yr-old sweet orange “Hamlin” trees planted at a density of 132 trees/acre. Five treatments and an untreated check were randomly distributed in an RCBD with four replicates in five-tree plots over four rows separated by buffer rows. Treatments were applied on 12 August to both sides of the trees with Durand Wayland AF100-32 air blast speed sprayer operating at 1.9 mph and 350 psi equipped with three John Bean ceramic nozzles 3, 4, 5 on each side delivering 100 gpa. Ten randomly selected shoots per plot were collected and examined under a stereomicroscope in the laboratory to count ACP nymphs and three fully expanded leaves on each shoot were examined to count CLM larvae at 3, 7, and 14 d after treatment (DAT). Density of ACP adults was assessed using stem tap sampling method whereby a randomly chosen branch was struck three times with a short length of PVC pipe and individuals falling on a white clipboard placed underneath were counted. Four tap samples were conducted per tree on three central trees in each plot through 28 DAT. Data were subjected to ANOVA and means separated using LSD ( P  = 0.05) are presented.

Significant reduction in ACP nymphs was observed through 14 DAT in all treatments except Fulfill +Dyne-Amic at 14 DAT which provided less reduction compared to other treatments and no control of adults compared with the untreated check ( Table 1 ). The remaining treatments provided similar levels of adult suppression through 21 DAT except A16971 + Dyne-Amic at 21 DAT. At 28 DAT, only Actara + Dyne-Amic provided significant reduction in adults. All treatments reduced CLM through 14 DAT except Fulfill + Dyne-Amic at 7 DAT. No phytotoxicity was observed.

Author notes