Studies on the Associates of Conocephalum conicum L . ( Dumort . ) and Dumortiera hirsuta Sw . ( Nees )

Paper includes information on association of 46 populations of Conocephalum conicum L. (Dumort.) and 25 of Dumortiera hirsuta Sw. (Nees) with diverse organisms, including fungi, bryophytes, pteridophytes, gymnosperms, angiosperms and an insect.


Introduction
Bryophytes are known to grow in close association with organisms as diverse as algae, fungi, bryophytes, pteridophytes, gymnosperms and angiosperms among plants and protozoa, rotifers, nematodes, earthworms, molluscs, insects and spiders among animals.Direct interaction of bryophytes includes providing food, shelter and nesting material for small mammals and invertebrates.Indirectly, they serve as a matrix for a variety of interaction between organisms [1].

Material and Method
Plants of Conocephalum conicum and Dumortiera hirsuta were collected along with their associates growing in diverse habitats, from different sites of tehsil Bhaderwah of district Doda of Jammu (India) region growing at altitude between 1230 -2600 m, the district falls between 32 degree-53' and 34 degree 21' North latitude and 75 degree-1' and 76 degree-47' East longitude.Periodical explorations were undertaken and field photography was done for the populations growing in natural habitats.

Observations and Discussion
A total of 12 plants and one insect species have presently been found associated with the two liverwort taxa.Among these, the most frequent association existed between Conocephalum conicum and Dumortiera hirsuta themselves.
A number of algal taxa are reported to grow in association with bryophytes.In the terrestrial habitat, cyanobacteria, especially Nostoc, are common, and green algae frequent.Nostoc is endophytic in some hepatics, for example Blasia (Metzgeriales), and in Anthocerotales, with which there is an obligate relationship.Since Nostoc is a nitrogen fixer, its advantage to the bryophytes is apparent.Frullania tamarisci is also reported as phorophyte for Stigonema cf.minutum [2].Observations on plant association of liverworts with other plant taxa were also earlier made by Fardos [3] for Reboulia hemispherica and reported its occurrence in association with one algal taxon Lyngbya.Similarly, Kapoor [4] observed filaments of Anabaena sp. and Vaucheria sp.growing on the dorsal surface of thalli of Riccia.
Bryophytes are also known to harbor the mycelia of zygomycetous and other fungi.Both hepatic taxa presently studied have been observed to grow in association with Glomus sp.(Figure 1(a)).Fungal hyphae were found associated with the smooth walled as well as tuberculated rhizoids.Their frequency, however, was far more in smooth walled one.
Conocephalum conicum has earlier been reported to grow mixed with mosses, such as Thuidium delicatulum and Mirella careyana [5,6].Association of Conocephalum conicum with Marchantia sp., Preissia quadrata, Reboulia hemispherica and occasionally with Riccardia pinguis, Pellia fabbroniana, Mannia rupestris and Clevea hyalina has also been reported [7].Report on the colonization of a typical liverwort dominated community consisting of Conocephalum conicum, Dumortiera hirsuta, Pellia endivaefolia, Chiloscyphus polyanthus, Phaeoceros himalayensis and Eurhynchium striatum is also known [8].The association of Conocephalum conicum with Dumortiera hirsuta, Wiesnerella denudata, Marchantia subintegra, Marchantia nepalensis, Pellia endivaefolia and mosses is also well observed [9].Observations on plant association of liverworts with other taxa were also earlier made [3] for Reboulia hemispherica and also reported it to occur in association with hepatics, (Plagiochasma appendiculatum, Marchantia polymorpha, Marchantia palmata, Asterella angusta, Chiloscyphus himalayensis), mosses (Rhodobryum roseum and Fissidens sp.) ferns (Asplenium dalhousiae and Adiantum capillus venaris), gymnosperm (Cedrus deodara) and angiosperms (Cynodon dactylon, Fragaria indica, Mazus pulmilus, Stellaria media and Oxalis sp.).Of the various plant associates recorded presently for the two plant species the best association was among Conocephalum conicum and Dumortiera hirsuta themselves.The reason behind such a strong association between these two thalloid liverworts is their ability to occupy the same microsites.Microhabitats and habitat structure are the basic requirement for plants to flourish in an ecological niche, which is almost same and cooperative for these thalloid liverworts.Data available for plant associates of the two taxa are summarized in the following Table 1.
The diversity patterns of among the associated organism groups along the investigated geographical gradient come out to be influenced by both climatic and management related factors (habitat fragmentation).There is no uncertainty that an increase in the habitats in the forests will increase diversity.The composition of substratum, microclimatic conditions and the habitat position are key  variables influencing species composition.It can be concluded that the studied taxa are an important factor in maintaining forest integrity and they are helpful as one conservation endpoint that integrates desirable characteristics such as natural biodiversity, stand structure and continuity.Bryophytes have been proposed as surrogates, because they are important components of forest integrity.

Table 1 . Different associates of Conocephalum conicum and Dumortiera hirsute.
Dryopteris radactopinnata) and only one flowering plant species (Salix alba) was common between the two indicating that the substratum requirement and habitat preference for these common plants growing in association with one another is same.This clearly indicates that the two hepatics studied presently have similar microhabitat requirements.