Fungal diversity driven by bark features affects phorophyte preference in epiphytic orchids from southern China.

Epiphytic orchids exhibit varying degrees of phorophyte tree specificity. We performed a pilot study to investigate why epiphytic orchids prefer or avoid certain trees. We selected two orchid species, Panisea uniflora and Bulbophyllum odoratissimum co-occurring in a forest habitat in southern China, where they showed a specific association with Quercus yiwuensis and Pistacia weinmannifolia trees, respectively.

Temporal turnover in mycorrhizal interactions: a proof of concept with orchids.

Temporal turnover events in biotic interactions involving plants are rarely assessed, although such changes might afford a considerable acclimation potential to the plant. This could enable fairly rapid responses to short-term fluctuations in growth conditions as well as lasting responses to long-term climatic trends. Here, we present a classification of temporal turnover encompassing 11 possible scenarios.

Partial mycoheterotrophy is common among chlorophyllous plants with Paris-type arbuscular mycorrhiza.

Background And Aims: An arbuscular mycorrhiza is a mutualistic symbiosis with plants as carbon providers for fungi. However, achlorophyllous arbuscular mycorrhizal species are known to obtain carbon from fungi, i.e.

Germination and seedling establishment in orchids: a complex of requirements.

Background: Seedling recruitment is essential to the sustainability of any plant population. Due to the minute nature of seeds and early-stage seedlings, orchid germination in situ was for a long time practically impossible to observe, creating an obstacle towards understanding seedling site requirements and fluctuations in orchid populations. The introduction of seed packet techniques for sowing and retrieval in natural sites has brought with it important insights, but many aspects of orchid seed and germination biology remain largely unexplored.

Composition of Cypripedium calceolus (Orchidaceae) seeds analyzed by attenuated total reflectance IR spectroscopy: in search of understanding longevity in the ground.

Premise Of The Study: Orchid seeds are minute and covered with a thin coat, yet they often have a long life after dispersal. They are notorious for low and irregular germination, in nature as well as in vitro. Since orchids are often rare species of conservational and commercial interest, reproduction by seeds is an important concern.

Ontogeny in terminal buds of Abies nordmanniana (Pinaceae) characterized by ubiquitin.

Meristematic activity in the bud meristem of Abies nordmanniana was visualized by ubiquitin immunohistochemical localization from before bud break and throughout shoot expansion. Ubiquitin was detected in meristematic cells either in the cytosol or nucleus, or both, depending on tissue type and developmental stage. During winter dormancy, ubiquitin was only observed in the protodermal/hypodermal layers, but at bud break in mid May, the signal expanded to the entire shoot tip.

Plagiotropism and auxin in Abies nordmanniana.

Main branches of Abies nordmanniana Spach. were examined through their first growth season from subapical buds around the leader bud to fully expanded shoots. Plagiotropism was evident in branch orientation, which was almost horizontal, as well as in the orientation of buds developing on the branches.

Molecular identification of mycorrhizal fungi in Neuwiedia veratrifolia (Orchidaceae).

We here apply a previously described method for identification of single peloton orchid mycorrhiza to a key orchid group and extend the usefulness in the heterobasidiomycetes of an existing fungal database for identification of mycorrhizal fungi. We amplified and sequenced mitochondrial ribosomal large subunit DNA from fungi in roots of Neuwiedia veratrifolia (Orchidaceae), a member of the small subfamily Apostasioideae that is sister to the remainder of Orchidaceae, and used the extended database to identify the mycorrhizal fungi. Sequences from fungi cultured from Neuwiedia roots and from direct peloton amplifications were analyzed cladistically with sequences determined from reference fungal collections and published sequences.

Phenology of roots and mycorrhiza in orchid species differing in phototrophic strategy.

• The mycorrhiza of orchids represents an energy source that may replace or supplement photosynthesis. Dependency on mycotrophy in adult life stages would thus be expected to be inversely related to the prevalence of phototrophic structures. • The phenology of underground parts and mycorrhizal infection were monitored in five terrestrial species differing in leaf phenology (and thus in phototrophic strategy): Goodyera pubescens (evergreen), Tipularia discolor (wintergreen), Galearis spectabilis and Liparis lilifolia (summergreen) and Corallorhiza odontorhiza (chlorophyll deficient), growing sympatrically in a North American deciduous forest.