Applications of PGRs to container-grown citrus trees affected the biology and behavior of the Asian citrus psyllid. In greenhouse and growth camber experiments, prohexadione and mefluidide applications to trees reduced ACP fecundity and survivorship, whereas uniconazole affected fecundity and paclobutrazol affected survivorship. These PGRs did not affect adult ACP weight, except when paclobutrazol was applied. Dikegulac appeared to inhibit ACP egg laying, but this was likely due to phytotoxicity. Oviposition was delayed and rate was lower on PGR-treated trees, but chlormequat under greenhouse conditions had an effect. The effect of PGRs on ACP did not appear to be due to growth retardation or specific toxicity of the materials, suggesting a yet undefined effect on plant physiology that altered host quality.