Systemic insecticides and reflective mulch for Asian citrus psyllid (Diaphorina citri) control in new citrus plantings

Greening or huanglongbing (HLB) is a devastating disease of citrus caused by Candidatus Liberibacter asiaticus and transmitted by the Asian citrus psyllid (ACP), Diaphorina citri. HLB now occurs worldwide in most citrus growing regions except the Mediterranean and Australia.  Management relies principally on insecticidal control of ACP which is insufficient, even for young trees which are most susceptible to the disease.  We tested the ability of metalized polyethylene mulch to repel adult ACP as well as effects on incidence of HLB and early tree growth with and without insecticide treatments as well as with and without foliar nutrition.  The experimental design is a 3-way factorial randomized complete split block design with 4 replications of 4 mail plot treatments :  (1) supplementary foliar nutrients only, (2) insecticides only, (3) nutrients plus insecticides, and (4) neither nutrients nor insecticides (control).   Each main plot was split with half being planted on metalized UV reflective mulch.  Evaluations of all treatments include ACP populations on flush and sticky cards, trunk growth measurements, and leaf samples tested for the presence of HLB.