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Valeriana wallichii DC. (Valerianaceae), a threatened medicinal plant of Himalayan region, has individuals showing 3 patterns of sex expression (female, hermaphrodite, and gynomonoecious). In the present study, the effect of floral size reduction on pollination efficiency of female flowers on female plants of Valeriana wallichii has been determined. To check entomophily as the possible mode of pollination, plants growing in nature are monitored whether or not the flowers are visited by some insects. Apis dorsata and Apis cerana are observed to be the main pollinators of this species. Female plants receive less pollinator service as compared to hermaphrodite plants. Reduced floral size in females offers more number of stigmas to get pollinated in a single visit as greater number of flowers get in contact with the visiting insect. The time of stigma receptivity also varies in female and hermaphrodite flowers. In females, it remains receptive for longer duration. Further, the pollen load on stigmata of open pollinated hermaphrodite as well as female flowers is studied. It is experimentally demonstrated that at the end of the season, the amount of pollen load is lesser in females as compared to hermaphrodites. Reproductive output of both types of individuals is estimated, and seed germination experiments are performed. Reproductive output and seed germination are more in females.

A protocol for rapid extraction of high quantity and quality of genomic DNA and Random Amplified Polymorphic DNA Polymerase Chain Reaction (PCR) analysis has been optimized for Ferula jaeschkeana Vatke (Apiaceae), an overexploited medicinally important species of Western Himalaya in India. The protocol utilizes preserved leaf material for DNA extraction. Liquid nitrogen was used for grinding the deveined leaf tissue. The isolated DNA was essentially free of polyphenolics, polysaccharides and other major contaminants as revealed by color difference of DNA isolated by the available protocols and the present one. Quantification of the isolated DNA was performed in a UV spectrophotometer (UV1800, Shimadzu) and the purity determined by calculating the ratio of absorbance at 260 nm to that of 280 nm (260/280 = 1.8–2.0). The quality and quantity of DNA was also visualized on 0.8 % agarose gel by comparing band intensity with that of standard amount of lambda DNA (165 μg/ml, Banglore Genei Pvt. Ltd., India). The isolated DNA was diluted to 25 ng/μl which was used for PCR amplification.

While studying meiosis in the male tract of Valeriana wallichii DC (Valerianaceae). polymorphism in size as well as chromosome number was observed in its pollen mother cells. The present report is based on study undertaken in ten populations of the species; 8 from J&K (India) and 2 from Uttrakhand (India). In all the anthers studied from plants of these populations, pollen mother cells could be differentiated as small (20–30 μm), medium (30–50 μm) and large sized (50–65 μm). In two populations (Noorichamb, J&K and Chakrata, UK), besides size, PMCs with different ploidy level were also observed. While the small and medium PMCs had normal chromosome number with 16 bivalents, some of the large PMCs were tetraploid having 64 chromosomes. Rarely, some pmcs at early prophase- I were also seen in a seemingly fusing state in some of the anthers. Size difference in PMCs also got reflected in the size of pollen grains and these could be classified as small (

Information on reproductive biology of threatened plant species could be useful for conservation, particularly when the species fails to perpetuate in nature due to regeneration failure. In flowering plants, the domain of reproductive biology includes structural details of reproductive units such as flower or inflorescence, formation of viable gametes, pollination dynamics, role of pollinators, pollen–pistil interactions as determined through compatibility, breeding system and mating strategies, fertilization and embryogeny, seed development, dispersal and germination. The importance of reproductive biology in species conservation has been demonstrated through a case study of Illicium griffithii Hook f. & Thomson, a threatened plant species from Arunachal Pradesh. I. griffithii (Illiciaceae) is a member of the ANITA clade and a representative taxon of the three most basal angiosperms. The flowers of I. griffithii are obligate xenogamous, and hence compatible pollen grains only germinate on the stigmatic papillae. Esterase and phosphatase enzymatic activities are absent in most stigmatic surfaces. Therefore, stigmatic receptivity is absent in many carpels. The ovules are anatropous and bitegmic with a four-celled/four-nucleate structure of embryo sac at maturity. Antipodals and filiform apparatus are absent. Presence of mucilage cells in the embryo sac facilitates the entry of pollen tubes into it. Embryolike organization of the endosperm is present, with one pole globular having smaller cells and the other pole roughly filamentous with larger cells resembling that of a suspensor. Extragynoecial compitum is not observed in I. griffithii . The flowers are brooding sites for the midges and the young ovules are eaten by larvae of the midges. Only 10% of the flowers mature into 13-seeded fruits and the carpels of the remaining 90% of the flowers have seeds ranging from 1 to 5. The seedling survival rate is only 7%. In addition to the above-mentioned reproductive bottlenecks, the species is also being over-harvested. It is now categorized as endangered. The findings of the present study on reproductive biology of I. griffithii should help in improving its conservation status.