Inula racemosa Hook. f. is protandrous, discharges pollen grains inside the anther tube and presents pollen secondarily onto the sweeping hairs of the style. The style and stigmatic branches present the yellow clumped pollen grains for pollination. This study describes floral functional morphology and phenology, anther dehiscence and pollen presentation, growth and behaviour of style during anthesis and pollination mechanism of I. racemosa. The species is entomophilous and is characterized by a highly asynchronous sexual phase. A large degree of asynchrony from floret to floret in a capitulum, and capitulum to capitulum in a plant, keeps the pollen dispersed for a longer duration. Two insect families were represented in the pollinator survey: Hymenoptera and Diptera. A significant correlation was observed between the number of capitula visited per bout and foraging time. We discuss morphological features of the flowers which may enhance the pollen removal rate per bee visit and consequently cause a high visitation and pollination rate.

Background:The species Inula racemosa, a rare species of Kashmir Himalaya, has been included in the list of endangered species of India. In the present study, we aimed to make a more formal quantitative analysis of the fertility of I. racemosa, wild as well as transplanted populations, using a meiotic behaviour analysis and pollen viability test. Material and Methods: Inflorescences at an ideal stage for meiotic study were collected and fixed in acetic ethanol (1:3) for 24 h and stored in 70% alcohol under refrigeration at 4˚C until use. For slide preparation the anthers were squashed in 2% acetocarmine. Results: The present study revealed a peculiar chromosomal stickiness and formation of interbivalent chromatin connections among 2-4 bivalents. This stickiness of chromosomes along with interbivalent chromatin connections impairs the correct segregation of chromosomes, as a result single and double chromosomal bridges of different thickness, different number of lagging chromosomes, unequal separation, and multipolarity were continuously observed from anaphase I to microspore stage. Consequent to stickiness and associated meiotic abnormalities, the pollen grains varied greatly in size, individuals show 24.05-38.83% pollen sterility. Conclusions:The presence of sticky chromosomes in I. racemosa impairs the correct segregation during anaphase which compromises the pollen viability of the species. Although the percentage of pollen sterility was not completely concord to the high rates of observed chromosomal abnormalities but the findings can aid in the successful conservation and management of the species.

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Nitrogen (N) is one of the indispensable nutrients required by plants for their growth, development, and survival. Being a limited nutrient, it is mostly supplied exogenously to the plants, to maintain quality and productivity. The increased use of N fertilizers is associated with high-cost inputs and negative environmental consequences, which necessitates the development of nitrogen-use-efficient plants for sustainable agriculture. Understanding the regulatory mechanisms underlying N metabolism in plants under low N is one of the prerequisites for the development of nitrogen-use-efficient plants. One of the important and recently discovered groups of regulatory molecules acting at the posttranscriptional and translational levels are microRNAs (miRNAs). miRNAs are known to play critical roles in the regulation of gene expression in plants under different stress conditions including N stress. Several classes of miRNAs associated with N metabolism have been identified so far. These nitrogen-responsive miRNAs may provide a platform for a better understanding of the regulation of N metabolism and pave a way for the development of genotypes for better N utilization. The current review presents a brief outline of miRNAs and their regulatory role in N metabolism.

Jurinea dolomiaea is an important medicinal and aromatic plant species of Kashmir Himalaya. Due to its tremendous overexploitation the species has been listed as endangered for Himalayan region. In this study we carried out the propagation of J. dolomiaea using rhizome cuttings. Propagation through rhizome cuttings is a means towards conserving the species and making available planting material of this species for cultivation. Bringing more species under large-scale cultivation helps reduce the pressure on the wild stocks. We investigated the sprouting ability and percentage survival of rhizome cuttings under ex situ conditions including soil textures, moisture contents and different concentrations of Indole acetic acid (IAA), Indole butyric acid (IBA) and Gibberellic acid (GA 3 ) treatments. A better rooting response (p ≤ 0.05) was observed with GA 3 25 ppm treatment when compared to zero hormone soaked.

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