The response of citrus plants to the broad mitePolyphagotarsonemus latus(Banks) (Acari: Tarsonemidae)

Abstract

Polyphagotarsonemus latus(Banks) (Acari: Tarsonemidae) is a common polyphagous mite in tropical and subtropical areas and is considered as an important citrus pest.To understand the response of citrus toP. latusinfestation, we have characterized the volatile profile and the molecular defence mechanisms of two citrus genotypes, namely sour orange (Citrus aurantium) and Cleopatra mandarin (Citrus reshni), toP. latusinfestation. These two species are important rootstocks for the citrus industry and display differential resistance toTetranychus urticaeKoch (Acari: Tetranychidae), with sour orange showing elevated levels of constitutive and induced resistance associated with the jasmonic acid (JA) pathway compared with Cleopatra mandarin.P. latusinfestation activated both the JA‐ and the salicylic acid‐dependent pathways in sour orange but not in Cleopatra mandarin. However, this differential activation resulted in the production of similar volatile blends (a mixture of green leaf volatiles and aromatic compounds).Contrary toT. urticaeinfestation, sour orange supported larger densities ofP. latusthan Cleopatra mandarin with similar injury levels.Therefore, sour orange may be more tolerant toP. latusthan Cleopatra mandarin.