Living on Leaves: Mites, Tomenta, and Leaf Domatia

Abstract

Structures on the surfaces of leaves strongly affect phylloplane mites. Glandular trichomes defend against some plant parasites but can also mire predators. However, leaves with tomenta of nonglandular trichomes are often inhabited by large populations of predatory mites. Tufts of hairs and other minute structures in the vein axils are called leaf domatia. Comparative observations and experimental data demonstrate that leaves with domatia have enhanced levels of predatory mites. By accumulating predatory mites, leaf domatia act as a kind of constitutive defense against herbivores. Mites benefit from leaf domatia by securing a safe place for oviposition and molting. Like several other plant structures, leaf domatia are the manifestation of a long-term and mutually beneficial interaction between plants and arthropods.

Domatia reduce larval cannibalism in predatory mites

“…It has been hypothesised that leaf domatia mediate mutualistic interactions between plants and predatory and fungivorous mites because they protect the mites against adverse conditions ( Pemberton & Turner, 1989;O'Dowd & Willson, 1991;Grostal & O'Dowd, 1994 ;Walter, 1996 ) and against other predators or omnivores ( Norton et al , 2001;Faraji et al , 2002a , b). Owing to this protection, the survival of predators on plants with domatia would be higher than on plants without domatia ( Agrawal & Karban, 1997;Agrawal et al , 2000;English-Loeb et al , 2002 ).…”

“…To achieve this indirect defence, plants produce herbivore-induced volatiles to attract predators and parasitoids ( Dicke, 1999;Janssen et al , 2002;Kessler & Baldwin, 2002 ), offer pollen and nectar as alternative food to the enemies ( Beattie, 1985;Pemberton & Lee, 1996;Sabelis & van Rijn, 1997 ), or provide shelter to natural enemies ( Beattie, 1985;O'Dowd & Willson, 1989;Pemberton & Turner, 1989;O'Dowd & Willson, 1991;Walter, 1996 ). Examples of shelter provided by plants are leaf domatia.…”

“…Examples of shelter provided by plants are leaf domatia. They are found in the bifurcation of veins on the underside of the leaves of many plant species ( O'Dowd & Willson, 1989;Pemberton & Turner, 1989;Grostal & O'Dowd, 1994 ;O'Dowd & Pemberton, 1994;Walter, 1996;Agrawal, 1997Agrawal, , 2000, and consist of tufts of hair, pockets, pits or pouches ( Pemberton & Turner, 1989 ). They are mainly inhabited by predatory and fungivorous mites and are therefore referred to as acarodomatia ( Pemberton & Turner, 1989;O'Dowd & Pemberton, 1998 ).…”

“…A mutualistic interaction between plants and the mites through leaf domatia has been hypothesised, with the mites being protected inside the domatia ( Norton et al , 2001;Faraji et al , 2002a ). This would result in increased survival of the mites, resulting in an increased consumption of herbivores or plant-pathogenic fungi, thereby providing benefit to the plant ( O'Dowd & Willson, 1991;Walter & O'Dowd, 1992;Grostal & O'Dowd, 1994 ;Walter, 1996 ).…”

Efeito da presa alternativa no desenvolvimento e consumo de Orius insidiosus (Say) (Hemiptera, Anthocoridae) e comportamento de oviposição em cultivares de crisântemo

“…Walter (1996) relatou que plantas com densa pilosidade propiciam maior eficiência de busca ao predador uma vez que fornece abrigo, além de estimular o deslocamento da presa em várias direções, facilitando o encontro e resultando, conseqüentemente, em maior predação.…”