The capacity to configure the hymenophore is not confined to the pore field in Oak mazegill (Daedalea quercina, Polyporales)

Abstract

AbstractConfiguring of the hymenophore of basidiocarps of Polyporales is thought to happen in the pore field immediately behind the basidiocarp margin. Basidiocarp growth is not restricted to the margin, however. Here, the importance of the pore field was assessed from observations on naturally occurring Oak mazegill (Polyporales, Daedalea quercina) basidiocarps and tested by experimental perturbations in natural habitats that were monitored for two years. Oak mazegill was chosen because the formed hymenophore has a unique and stable combination of poroid and lamellate features. Whether the pore field is required for basidiocarp growth was tested in ten basidiocarps in which one side was resected. New growth was observed in six basidiocarps and it occurred equally from the cut hymenophore and the intact pore field. New formation of hymenophore and pileus even occurred in seven out of ten basidiocarps that had the entire pore field resected. Whether the hymenophore is configured permanently, was tested on 54 basidiocarps on ten trunks that were turned upside-down. A new hymenophore grew through the old pileus, often far from the pore field, and its hymenophore configuration was invariably poroid despite the old hymenophore had lamellate features. In 48 experimentally banded basidiocarps, new hymenophore grew in the insertion hole of the band despite this being far from the pore field. The banded basidiocarps grew at an average rate of 5 mm per year. In conclusion, the capacity to configure the hymenophore is not confined to the pore field and it may be broadly present in the basidiocarp.Graphical abstractGraphical abstract. The configuring of the hymenophore of polypore fungi is thought to be driven by the pore field immediately behind the basidiocarp margin. The experiments on Oak mazegill basidiocarps reported here, including the complete resection of the margin and its pore field, do not support this notion. They suggest instead that the capacity to form the hymenophore is broadly present in the basidiocarp.