Wood apple, Limonia acidissima L.: A New Host For the Huanglongbing (Greening) Vector, Diaphorina citri

Abstract

A study was conducted in Thailand to determine the host range of psyllid, Dia-phorina citri, and the huanglongbing (HLB) (greening) pathogen it transmits. Approximately six-month-old seedlings of 15 Rutaceae plants including three citrus cultivars were exposed to D. citri that had fed on HLB-infected citrus plants collected from Thailand. Long-term survival of the psylla of more than 7 wk was observed on the following plants: Balsamocitrus dawei, Murraya paniculata, M. koenigii, Limonia acidissima (wood apple), Atalantia sp., Severinia buxifolia, Pon-cirus trifoliata and Som-pan and Som-keo-wan mandarins. Among them, marked multiplication of psylla was noted on M. paniculata, Atalantia sp. and L. acidissima. The former two did not develop any symptoms, but the L. acidissima developed leaf mottling and yellowing. An electron microscope study failed to show conclusive evidence of HLB organisms in sieve cells of infected L. acidissima. These results indicate that wood apple is a new host for D. citri and warrants further investigation as a possible host of the HLB agent.