In the recent advancements in identification of plant species, phytoliths have found an immense role in the identification of plants at different levels of taxonomic hierarchy. Many plant groups are known to accumulate silica in solid form in and between the cells and tissues and hence create the structures commonly known as phytoliths. These phytoliths create replicas of the structures where they are deposited. The shapes of phytolith replicas, their size dimensions (morphometric parameters), surface features (ornamentation), distribution, and orientation pattern in epidermal layers of vegetative and reproductive structures as well as their frequency are highly important for characterization of species. Monocotyledonous families particularly the family Poaceae (Gramineae) are known to produce diverse phytolith types that can serve as diagnostic markers for characterization of different taxa at different levels of taxonomic hierarchy. The present paper highlights the importance of phytoliths in taxonomic analysis of plants particularly in the family Poaceae.

Grasses (Poaceae) are the foremost silicon (Si) accumulators among terrestrial plants. Plants take up Si as monosilicic acid, Si(OH)₄, which polymerizes in cells and tissues such as the epidermis, xylem and phloem to form phytogenic (biogenic) silica, SiO₂ · nH₂O, deposited as phytoliths. This review, based on a documented literature search with explicit inclusion and exclusion criteria, evaluates evidence that phytoliths protect grasses against herbivores, fungal and bacterial pathogens and nematodes, and against drought, heat, salinity, metal toxicity, UV-B radiation and mechanical stress, and it examines combined stresses under climate change. We distinguish phytolith-specific evidence from studies that supplied soluble Si or Si nanoparticles, and we grade the evidence for each proposed mechanism. Physical mechanisms (abrasion, mechanical and apoplastic barriers, reduced non-stomatal water loss) are the best supported. Biochemical and hormonal mechanisms, including jasmonic acid, salicylic acid and ethylene signaling, remain hypotheses because Si(OH)₄ is chemically inert and much of the evidence is correlative. Elevated CO₂ can lower foliar Si concentration in some grasses, which may weaken protection, but effects on total Si accumulation and function are poorly known. Phytolith-occluded carbon is a potential but uncertain carbon sink. We identify research priorities and practical implications for crop, pasture and carbon management.

Floriculture is the branch of horticulture that deals with the cultivation and management of flowers and ornamental plants and has blossomed into commercial activity with considerable growth and a useful crop diversification option, particularly for small farmers over the past three decades. It is a global industry with significant economic, social, and aesthetic values. Globally 171 countries practice floriculture. India occupies 51st position in terms of exports and contributes Rs. 455 crores which is 0.06% of global trade. The present study was carried out during the College on Wheels project organized by the Higher Education Council, Union Territory of Jammu & Kashmir, and was aimed to explore the floral and ornamental plant diversity of major metropolitan cities like Delhi, Goa, Bengaluru, Mumbai, etc. of India for evaluating their suitability for introduction in floriculture of Union Territory of Jammu & Kashmir. The floral and ornamental plant species were explored, photographed, evaluated, identified, and inventorised. A total of 51 species belonging to 23 different families of floral and ornamental plants were explored and evaluated in terms of parameters like climate, soil type, photoperiod requirements, watering needs, and maintenance requirements for their cultivation. It was found that some of the explored species of ornamental plants were already introduced into the Union Territory of Jammu and Kashmir because the parameters for the successful growth and thriving of these species match with the existing climatic and other conditions in the Union Territory of Jammu and Kashmir. Besides, the climatic and other requirements of some of the explored species were found in conformity with the climatic and other parameters available in the Union Territory of J&K for the successful establishment and growth of plants. Thus, there is an urgent need to introduce these explored species into the region to enhance the floral diversity of ornamental plants, beautify the landscape, and promote tourism and the generation of better livelihood. The Department of Floriculture should take a lead role in this direction to import these floral and ornamental plant specimens from pan India.