Floristic diversity in Valley of Flowers National Park, Indian Himalayas

Floristic diversity of Valley of Flowers National Park, Uttarakhand, a world heritage site in Indian Himalayan Region has been documented. A total of 614 taxa (609 species, 3 subspecies and 2 varieties) belonging to 277 genera and 70 families have been recorded. Among these, 31 plant species are under different threat categories, 05 endemic and one plant namely Cuscuta europaea recorded as invasive. The paper, for the first time, records 72 plant species as additions to flora of Valley of Flowers National Park. Importance of floristic diversity and conservation needs are also discussed.

Stable transformation and actin visualization in callus cultures of dodder (Cuscuta europaea)

Agrobacterium tumefaciens-mediated transformation of callus culture, combined with a visual selection of GFP-tagged fimbrin actin binding domain (FABD2) expression is described for parasitic species (Cuscuta europaea). The conditions for callus induction from 1 cm-long explants from the basal part of 7-day-old dodder seedlings were defined. We obtained light-green calli, which were transformed with A. tumefaciens bacterial strain GV3101 carrying plasmid pCB302 (35S::ABD2:gfp) with neomycin phosphotransferase (nptII) gene. The limitations of selection procedures based on antibiotics were avoided using green fluorescent protein (GFP) detection, as a visual selection marker subcellularly targeted to the actin cytoskeleton. Fluorescence microscopy analyses demonstrated a network of nucleus-associated actin arrays and dense cortical actin arrangements in stably transformed Cuscuta callus cells. RT-PCR analyses confirmed gfp expression in transformed calli 7, 14 and 21 days after transformation. Although the GFP fluorescence associated with the actin cytoskeleton has retained for at least six months without silencing, no shoot regeneration was observed. It can be concluded that, C. europaea callus cells are competent for transformation, but under given conditions, these cells failed to realize their morphogenic and regeneration potentials.

Dormancy, germination requirements and storage behaviour of seeds ofConvolvulaceae(Solanales) and evolutionary considerations

Convolvulaceaeis the only family in the asterid clade with species that produce physically dormant seeds, and most studies on germination in this family have focused on scarified seeds. However, no study has been done on the taxonomic/evolutionary pattern of seed dormancy inConvolvulaceae. We determined the moisture content of non-treated seeds and water uptake and germination percentages for non-treated and manually scarified seeds of 46 species in 11 of the 12 tribes in this family. Germination was tested over a range of temperatures in light/dark and in the dark. The effect of drying and storage at low temperatures was tested on seeds ofErycibe henryiandMaripa panamensis, the only species with high initial moisture content. Non-treated fresh seeds ofBonamia menziesii,M. panamensisandE. henryiimbibed water, whereas those of the other 43 species did not. Manually scarified seeds of all these 43 species took up large amounts of water. Therefore, seeds of 43 of the 46 species are physically dormant, and three are non-dormant. Seeds of all 46 species germinated after imbibition, except those ofCuscuta europaea, which are reported to have combinational dormancy.M. panamensisandE. henryiseeds are recalcitrant and those of the other 44 species orthodox. InConvolvulaceae, basal tribes or tribes derived from basal tribes contain species with non-dormant recalcitrant, physically dormant orthodox and combinationally dormant orthodox seeds. Physical dormancy of seeds in this family possibly evolved from a non-dormant recalcitrant seed-producing ancestor closely related toErycibeae.