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Ectomycorrhizal (EM) fungi being obligate mutualists of roots of several vascular plants have a major role in diversity, biogeography, erosion prevention, and biogeochemical cycles. Recent findings depict that the EM fungi have multifunctional roles in ecosystem processes leading to valuable ecosystem services. They are the main players in reclamation of degraded ecosystems based on their ability to develop stress tolerance, nutrient acquirement, and bioremediation. Although the Western Ghats has been recognized as an important hotspot of biodiversity in the tropics, studies on the EM fungi are fairly meager. This review is an attempt to consolidate the research on the EM fungi in different parts of the Western Ghats addressing their diversity, distribution, and ecology. A total of 148 species (34 genera) of EM fungi has been known from the Western Ghats. Inocybe is the dominant genus (36 spp.) followed by other genera Russula (31 spp.) and Amanita (13 spp.). The host trees that supported the EM fungi consist of 60 species (40 genera). Vateria indica showed the highest EM fungi (69 spp.) followed by Hopea ponga (50 spp.), Hopea parviflora (48 spp.), and Diospyros malabarica (37 spp.). Eight tree species of Dipterocarpaceae supported up to 77% of EM fungi, while 15 exotic trees supported only 20%. Up to 30 new EM fungi are known from the Western Ghats. Importance and association of EM fungi with hosts and future research directions are emphasized.

Tropical agro-forest landscapes are potentially valuable reserves of forest genetic resources for forestry and restoration of degraded forests. The Dipterocarpaceae is a dominant Southeast Asian family of tree species of global significance for the tropical timber industry. Very little information exists about how effective human modified landscapes are for conserving genetic diversity in dipterocarp species. This study provides a baseline for understanding how fragmented agro-forest landscapes in India sustain forest genetic resources in an endemic dipterocarp tree. We compare genetic diversity and fine-scale spatial genetic structure (FSGS) in the threatened tree species Vateria indica within an isolated and a continuous forest site in the Western Ghats, South India. We place these results in the context of dipterocarps from both the Seychelles and Borneo. Parentage analysis of 694 progeny using twelve nuclear microsatellite markers is applied to estimate pollen and seed dispersal. Using a nursery trial we evaluate effects of inbreeding on growth performance. Our results show that levels of FSGS, and gene dispersal are comparable between a small isolated and a large continuous site of V. indica. Realized long-distance pollen flow into the isolated patch appears to help maintaining genetic diversity. The nursery experiment suggests that selection favours outbred progeny. Individuals of V. indica in close proximity appear less related to each other than in another highly fragmented and endangered dipterocarp species from the Seychelles, but more related than in three dipterocarp species studied in continuous forest in Borneo. We discuss the wider implications of our findings in the context of conservation and restoration of dipterocarp forest genetic resources in fragmented populations.

While conducting a survey in the Western Ghats, we recently came across several populations of a mycohetertrophic orchid species, Aphyllorchis montana Rchb.f. during our ongoing ecological research in Soppinabetta forests (SBF) of Chikmagalur District in the central Western Ghats. The paper provides the details on the population structure and ecology of the species in SBFs of Sringeri. Fourteen different SBFs were surveyed to record the orchid shoots and clumps during the monsoon months from June-October in 2007 and 2008. Orchid clumps were located in five SBFs that were separated by a distance of 6 and 20 km from each other. Orchid clumps were located in the SBFs having either one of the three dipterocarp plant species, Hopea ponga (Dennst.) Mabb., Hopea parviflora Bedd. and Vateria indica L., as a dominant canopy tree. The local-scale leaf litter study showed that the leaf litter composition in the near vicinity of orchid clumps was clearly dominated by either of the above-mentioned species. This indicates that the associated host mycorrhizal fungi may be specific to the dipterocarpacean tree species. The possible reasons for the data deficient status of the species are discussed.

Phytosociological analysis reveal that Palaquium ellipticum and Knema attenuate are the common dominant species present with their co- dominants such as, Memecylon decanese, Macranga peltata, Vateria indica etc. More than fifty percent of the established seedlings are contributed by the dominant and co- dominant species. Thus there is a gradual shift of natural evergreen species composition to the more light demanding moist deciduous elements. DOI: http://dx.doi.org/10.3126/apjeesd.v1i1.9508Asia Pacific Journal of Environment Ecology and Sustainable Development 2013; 1: 29-31

We investigated the links between slope variation and heterogeneity in tree growth and stand structure. The study was conducted in an undisturbed wet evergreen forest in India. We selected three plots situated on gentle slopes and three plots situated on steep slopes. Tree growth was considered as mean annual diameter increment. Stand structure was considered in relation to several characteristics: trunk diameter distributions, tree heights, and spatial distributions of stems and crowns. Except for the spatial structure, analyses were performed on samples including either all the species or only the dominant species (Vateria indica L.). Diameter growth varied according to slope intensity and to tree size: growth of large trees was clearly higher on steep slopes whereas growth of small trees proved lower or similar. Diameter distributions were different among the six plots, but the difference cannot be related to slope intensity. On the contrary, tree heights differed according to slope intensity: for a given diameter, trees were taller on gentle slopes than on steep slopes. Finally, stem spatial distributions showed strong regularity on gentle slopes whereas they were random on steep slopes. The observed changes between gentle and steep slopes suggest differences at tree level through a modification of its shape, but also differences in the major processes responsible for stand dynamics: competition, establishment and survival.

Conservation Genetics Resources, 5 (2), ISSN:1877-7252, ISSN:1877-7260

The Dipterocarpaceae are a globally significant family of tropical timber trees. They are especially dominant in lowland rainforests of Southeast Asia, but have a pan tropical distribution. Vateriopsis seychellarum is the sole representative of this family on the Seychelles. Historically one of the dominant canopy trees on Mahe, extensive overexploitation of this species for its timber has led to its virtual extinction. The last individuals of this species are found in small fragmented populations at lower altitudes (up to 400 m) on the island of Mahe where the total number of known reproductive adults is 112. We developed ten polymorphic microsatellite loci for this species to enable us to quantify the levels of diversity in remnant populations and to study genetic structure and contemporary gene flow. In addition we tested for cross amplification of these alleles in the closely related but geographically disjunct species Vateria indica. In Vateriopsis seychellarum the number of alleles per locus ranged from 6 to 20 (mean of 11.4 per locus) with an average polymorphic information content of 0.73 across loci. Expected heterozygosity ranged from 0.40 to 0.71 with 3 of the 10 loci showing deviation from Hardy–Weinberg expectations. 8 of the 10 primers showed cross amplification in Vateria indica. These markers will help to provide a better understanding of the significance of historic distributions, gene flow and recent anthropogenic habitat degradation for the survival of widespread species in recently fragmented landscapes.

A permanent plot of 28 ha was established in a dense wet evergreen forest in the Western Ghats of India to study the functioning of the ecosystem. Since April 1990, 1981 trees of ≥30 cm gbh have been enumerated in a systematic sampling of five strips totalling 3.12 ha. This paper describes the main structural and floristic characteristics of the plot.The density (635 trees ≥30 cm gbh per hectare) and basal area (39.7 m2 ha−1) are high. Despite the high diversity (Simpson's D = 0.92 and Shannon's H' = 4.56), four species are distinctly, dominant in terms of an importance value index (relative density + relative basal area). Each of these four species occupies a different layer in the ecosystem: Humboldtia brunonis Wall. (Fabaceae) dominates the undergrowth, Myristica dactyloïdes Gaertn. (Myristicaceae) the intermediate strata, Valeria indica L. (Dipterocarpaceae) the higher canopy level and Dipterocarpus indicus Bedd. (Dipterocarpaceae) the emergents. This pronounced species hierarchy is one of the most important characteristics of the evergreen forests of the Western Ghats. The two dipterocarps account for 20.1% of the total number of trees and contribute 40.9% to the total basal area. This formation can, therefore, be considered as the westernmost lowland dipterocarp forest of Asia.Analysis of the spatial variations in the floristic composition and in the structure of the main species populations shows that two kinds of mature phases can be identified: where the topography is raised and gently sloping, the vertical structure of the stand is discontinuous, with Dipterocarpus indicus and Vateria indica forming an emergent layer above a dense undergrowth; on slopes, the stand is lower, vertically continuous and saturated with Valeria indica and Myristica dactyloïdes. The link between the structure of the stand and dynamic processes is discussed.