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Physical seed characteristics of 32 threatened Western Himalayan orchids belonging to 23 genera of 3 subfamilies were studied using light and scanning electron microscopy. The species showed remarkable seed shape variations (fusiform, spathulate, ovoid, filiform) irrespective of their taxonomic position. Epiphytes produced relatively small-sized seeds compared to their terrestrial, lithophytic, or mycoheterotrophic counterparts. Seeds were truncated (length/width < 6.0) in 27 species, and were mostly elongated (length/width = 19.957 ± 1.459) in the orchidoid species Goodyera biflora (Lindl.) Hook.f. The number or size of testa cells was found fairly consistent at the genus level, and their walls were straight, sinuous, or undulate. Periclinal walls possessed vertical or oblique ornamentation in 6 species, which is of taxonomic implication. Embryos were rather tiny and most of the seed space (even >90% in 7 species) was occupied by air. The highest seed to embryo volume ratio was recorded in terrestrial Liparis odorata (Willd.) Lindl. and the lowest in epiphytic Rhynchostylis retusa (L.) Blume, both of which are members of the advanced Epidendroideae. Seed characteristics are important in elucidating taxonomic, phylogenetic, and phytogeographic relationships among different orchid taxa.

A protocol for their long term storage at low temperature has been developed using synthetic seeds technology in Cymbidium pendulum (Roxb.)Sw. in present piece of work. This species is known as an important ornamental and medicinal orchid. Protocorm Like Bodies (PLBs) were used as propagules for encapsulation. They were raised on Basal M medium [1], in addition with inorganic plant growth regulators such as [Indole-3-acetic acid (IAA); Indole-3-butyric acid (IBA) and Naphthalene acetic acid (NAA); 6-Benzyl amino purine (BAP); Kinetin (KN) at 1mg/l concentrations. Different combinations were compared for their efficacy in supporting large scale production of elite propagules for encapsulation. Among these NAA proved to be the best as it supported 99.5% of asymbiotic seed germination in to largest PLBs (2.2mm) with highest chlorophyll content at 2.15µg/mg. PLBs were encapsulated in 3% sodium alginate and di-hydrated salt calcium chloride (100mM). Resultant synthetic seeds were observed for their viability after different period of storage at 250C and 40C. Role of AC if added to nutrient matrix in extended storage of synthetic seeds with better conversion at mass scale has been the main focus of the study. Interestingly, AC supplemented synthetic seeds could be stored for 480 days with 10.5% conversion and showed fairly good regeneration or production of secondary PLBs.