Center for Ecological Research, Kyoto University, Sakyo, Kyoto, Japan 606-8502;
Am J Bot. 2000 Mar;87(3):440-5.
A previously undescribed pollination system involving a monoecious tree species, Artocarpus integer (Moraceae), pollinator gall midges, and fungi is reported from a mixed dipterocarp forest in Sarawak, Borneo. The fungus Choanephora sp. (Choanephoraceae, Mucorales, Zygomycetes) infects male inflorescences of A. integer, and gall midges (Contarinia spp., Cecidomyiinae, Diptera) feed on the fungal mycelia and oviposit on the inflorescence. Their larvae also feed on the mycelia and pupate in the inflorescence. The gall midges are also attracted by female inflorescences lacking mycelia, probably due to a floral fragrance similar to that of male inflorescences. Because of the sticky pollen, dominance of Contarinia spp. in flower visitors, and pollen load observed on Contarinia spp. collected on both male and female inflorescences, Artocarpus integer is thought to be pollinated by the gall midges. Although several pathogenic fungi have been reported to have interactions with pollinators, this is the first report on a pollination mutualism in which a fungus plays an indispensable role. The pollination system described here suggests that we should be more aware of the roles fungi can play in pollinations.
本文报道了来自婆罗洲沙捞越混交林的一种雌雄同体树物种——桂木（桑科）的一个以前未描述的授粉系统，涉及粉虱科的雄花虫瘿和真菌。真菌 Choanephora sp.（Choanephoraceae，Mucorales，Zygomycetes）感染桂木的雄性花序，粉虱（Contarinia spp.， Cecidomyiinae，双翅目）以真菌菌丝为食，并在花序上产卵。它们的幼虫也以菌丝为食，并在花序中化蛹。粉虱还被缺乏菌丝的雌性花序吸引，可能是由于与雄性花序相似的花香。由于花粉粘性强、粉虱在花访客中占优势，以及在收集的雌雄花序上采集到的粉虱上观察到的花粉负荷，因此认为桂木是由粉虱授粉的。尽管已经报道了几种病原菌与传粉者之间存在相互作用，但这是第一个报道真菌在授粉共生中发挥不可或缺作用的报告。这里描述的授粉系统表明，我们应该更加意识到真菌在授粉中可以发挥的作用。
