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The microphysics behind the formation of rain droplets is an important feature influencing orographic precipitation at any location. The raindrop microphysics were determined for the precipitation in Mahabaleshwar, the orographic region of the Western Ghats in the Indian subcontinent, using Joss–Waldvogel Disdrometer (JWD) observational data for the period from 2013 to 2019. Smaller (< 1 mm) rain droplets were found to be dominant in monsoon seasons, while in the pre-monsoon and post-monsoon, a higher concentration of medium-sized (1–3 mm) and larger (> 3 mm) rain droplets were observed. In each season, the peak rain droplet concentration moved toward giant rain droplets with increasing rain rate. The probability density function of mass-weighted mean diameter (Dm), normalized-intercept parameter (log10Nw), rain rate (log10R), liquid water content (log10W), shape parameter (µ), and slope parameter (Λ) indicate a clear distinction in all three seasons. High Dm and lower log10Nw mean values were observed during the convective precipitation, while the opposite was observed during the stratiform rainfall of each season, except for the post-monsoon convective precipitation. Monsoon rainfall of both convective and stratiform nature had the lowest Dm and highest log10Nw compared to the respective cloud structure of pre-monsoon and post-monsoon. The Dm and log10Nw values in post-monsoon stratiform rain lay between the values observed in the monsoon and post-monsoon seasons. At the same time, the convective precipitation in the post-monsoon had the highest Dm value, with a larger log10Nw than the pre-monsoon convective precipitation. A unique µ-Λ quadratic equation was also determined for the pre-monsoon, monsoon, and post-monsoon season rain events. [ABSTRACT FROM AUTHOR]

Decalepis salicifolia (Bedd. ex Hook. f.) Venter is a potential medicinal and highly aromatic plant species confined to the southernmost part of the Western Ghats of India. The plant is well known for its traditional uses among the various tribal communities of south India. The tubers of the plant possess characteristic vanillin-like aroma due to the presence of the compound 2-hydroxy-4-methoxybenzaldehyde. The tubers are used to substitute Hemidesmus indicus in various herbal formulations. The plants in the wild are continuously uprooted for their roots, leading to the irreversible destruction of the whole plant. The resulting tremendous loss of populations in the wild led to the species being declared as critically endangered by IUCN. Our group is working on the various aspects of this species including population status, distribution mapping, prospection, and conservation management. In the present review, we have brought out the available information till date on D. salicifolia, including taxonomy, ethno-medicinal uses, phytochemistry, pharmacology, population status, and conservation efforts along with research gap and lacunae to provide direction for further research into this less explored medicinal and aromatic plant. [ABSTRACT FROM AUTHOR]

Information on the genetic diversity and population structure is essential for developing conservational management programs, especially for threatened species. Decalepis salicifolia (Bedd. ex Hook.f.) Venter is a steno-endemic and critically endangered species of the south Western Ghats of India. The present study used ISSR markers as well as essential oil profiling to reveal the extent and distribution of genetic as well as the chemical diversity of all the twelve known populations of D. salicifolia. A total of 84 amplicons generated using 17 ISSR primers represented an overall 72.34% polymorphism. The highest percentage of polymorphic loci was recorded in the population of Theemalai (40.48%) and lowest in Kokanmalai (4.76%) with an average of 20.04% across all the studied populations. At the species level, the Nei's genetic diversity observed was 0.255 ± 0.186, while Shannon's information index observed was 0.385 ± 0.260. The genetic similarity-based unweighted pair-group method with arithmetic average dendrogram grouped the populations according to their geographic locations, which was corroborated by principal component analysis and Bayesian clustering. Distribution of genetic variance through analysis of molecular variance indicated that 38% variance resides within the population, and 62% variance resides among the populations (P < 0.001). Gas chromatography analyses of root volatiles showed significant variation in the percent content of 2-hydroxy-4-methoxybenzaldehyde. The Mantel test analyses showed a positive correlation between the genetic versus geographic distances. Based on the results, both ex situ and in situ conservation strategies are suggested to maximally preserve the genetic resources of this endangered species. [ABSTRACT FROM AUTHOR]