MITE ASSOCIATION WITH THE LEAF DOMATIA OF COFFEE (COFFEA-ARABICA) IN NORTH QUEENSLAND, AUSTRALIA

The primary coffee of commerce, Coffea arabica, has well-developed pit domatia in the primary vein axils on the undersurfaces of the leaves. In plantations near Mareeba and Daintree in far north Queensland, Aus tralia, these morphogenetic structures are commonly occupied by mites. Mites used domatia on over 80% of all leaves examined, and 41% of all domatia had been occupied by mites (15-28% on young leaves and 54-59% on older leaves at Mareeba, and 58% overall at Daintree). At Mareeba, domatia use by mites did not differ among plants or shoots within pla nts but did vary significantly with leaf position within shoots, a ref lection of leaf age. Domatia were important sites for mite reproductio n and development; 93% of the eggs and all moulting mites on leaves we re in domatia. Seven mite taxa were identified on leaves at Mareeba an d nine were present at Daintree. With the exception of Fungitarsonemus sp. and Brevipalpus obovatus Donnadieu at Mareeba, all were concentra ted in leaf domatia. Almost all mites in domatia were from groups in w hich arboreal representatives are primarily predatory (e.g., Stigmaeid ae, Phytoseiidae, and Bdellidae), fungivorous (e.g., Winterschmidtiida e, Oribatida and Acaridae), or both (Tydeidae and Tarsonemidae). The d ata suggest that domatia influence the distribution and abundance of p redatory and fungivorous mites that have the potential to affect funga l pathogens and some arthropod pests on coffee leaves.