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An efficient in vitro regeneration protocol has been developed from shoot tips of Drosera burmanniiVahl., a carnivorous plant of north-east India. Various plant growth regulators were used to study their efficacy in the induction of multiple shoots and roots. Of the various treatments, the maximum number of shoots (28.8 ± 1.5) and roots (9.7 ± 0.6) was observed in one-fourth strength standard medium (MS with 50 mg/l citric acid and 10 mg/l ascorbic acid) supplemented with 4 mg/l 6-benzylaminopurine (BAP) and 4 mg/l α-naphthalene acetic acid (NAA) followed by 26.8 ± 1.4 shoots in one-fourth strength SM fortified with 4 mg/l kinetin (KN) and 4 mg/l NAA. The well-developed plantlets with shoots and roots were potted in small plastic glasses filled with a mixture of sand and farmyard manure (3:1); these plantlets when transferred to a glasshouse for hardening and acclimatization showed 90% survival.

Embryogenic suspensions of Pinus kesiya(Khasi pine) derived from embryogenic cultures obtained from immature zygotic embryos (intact megagametophytes) of Pk-04genotype were grown in shake-flasks and self-designed bubble bioreactors. Conifer somatic embryogenesis could find its utility for rapid mass propagation if grown as suspension cultures. To minimize the destruction of embryogenic cultures during study, a few growth characteristics viz., sedimented cell volume and number of stage-I (early stage) and -III (cotyledonary) embryo formation in suspensions were determined over a 21-day period. Compared to shake-flasks, proliferation in bioreactors resulted in increased biomass. The suspension culture showed a mixture of freely suspended as well as aggregates of stage-I (early stage) embryos. Maturation of somatic embryos was done on gelled medium and in submerged culture where gelled solid medium was covered with a layer of liquid medium. The number of stage-III (cotyledonary) embryos formed in bubble bioreactor were significantly higher than shake-flask cultures with both solid medium and submerged cultures. The cotyledonary embryos germinated successfully producing plantlets on germination medium.

Synthetic seed technology is an exciting and rapidly growing area of research as deals with conservation and storage of rare, endangered and desirable genotypes along with its easy handling and transportation. As propagation of many ornamental and medicinally important plant species is labour intensive, application of different growth retardants and osmotica in simple artificial seed system would dramatically reduce labour requirement by storing the germplasm in vitro. Moreover, the primary aim of developing in vitro storage methods is to reduce the frequent demands of subculturing and preserving the unique genetic constituent of the germplasm. Dendrobium nobileis a pharmaceutically important orchid mostly used in the Chinese herbal drug industry for its medicinal property. Commercial exploitation of this species has considerably depleted their population in wild. Hence, for conserving this valuable germplasm, short term in vitro storage of Protocorm-Like Bodies (PLBs) of D. nobilewas carried out using different osmotica (sucrose and mannitol). It was observed that incorporation of low sucrose and mannitol (3 and 5 %) in the encapsulating matrix showed almost similar results with that of control. In all these cases, more than half of PLBs burst out from the matrix thus making these concentrations of sucrose and mannitol along with control not suitable for storage studies. However, with the increase in concentration to 7.5 and 12.5 % in the encapsulating matrix, no outburst of encapsulated PLBs was recorded till 60 days of storage; hence it can be concluded that these concentrations play an important role in minimizing the growth of PLBs during storage condition.

Thirty-five inter-simple sequence repeat (ISSR) markers were used to analyze the genetic variation in Cymbidiumspp. High number of polymorphic bands (217) with overall 90 % of polymorphism at inter-specific level was observed. Cumulative genetic similarity ranged from 0.40–0.93 with an average value of 66 % among the species. At intra-specific level, average polymorphism detected, ranged from 29.8 to 69.9 % within the five species of Cymbidium. All the species were apparently endowed with low genetic variation at intra-specific level compared to inter-specific level. UPGMA clustering evidently distinguished the representatives of C. aloifoliumand C. tigrinumwhich may be linked to entirely different climatic conditions in which they grow, besides their discrete morphological characteristics. Nine ISSR primers revealed 11 unique species-specific banding patterns belonging to three Cymbidiums, which can further developed as SCAR markers. Thus, present investigation provides valuable baseline data of genetic variation in five species of Cymbidiumand addresses the conservation concerns of this horticulturally important orchid.Thirty-five inter-simple sequence repeat (ISSR) markers were used to analyze the genetic variation in Cymbidiumspp. High number of polymorphic bands (217) with overall 90 % of polymorphism at inter-specific level was observed. Cumulative genetic similarity ranged from 0.40–0.93 with an average value of 66 % among the species. At intra-specific level, average polymorphism detected, ranged from 29.8 to 69.9 % within the five species of Cymbidium. All the species were apparently endowed with low genetic variation at intra-specific level compared to inter-specific level. UPGMA clustering evidently distinguished the representatives of C. aloifoliumand C. tigrinumwhich may be linked to entirely different climatic conditions in which they grow, besides their discrete morphological characteristics. Nine ISSR primers revealed 11 unique species-specific banding patterns belonging to three Cymbidiums, which can further developed as SCAR markers. Thus, present investigation provides valuable baseline data of genetic variation in five species of Cymbidiumand addresses the conservation concerns of this horticulturally important orchid.

The population of many splendid orchids is reducing from their natural habitats at an alarming rate and their conservation is becoming a matter of global concern. Asymbiotic seed germination has been applied for ex situ conservation of rare, endangered and threatened orchid taxa and could provide rapid means their multiplication. In the present study reported here, seeds of an epiphytic and rare orchid, Cymbidium eburneumwere germinated asymbiotically in different basal media viz., Murashige and Skoog (MS), Knudson C, Mitra et al. (Mitra), Gamborg et al. (B5) and Nitsch. The highest germination rate was observed in Mitra medium, whereas the development of the protocorms was found to be best in MS medium. Effects of growth regulators viz., indole-3 acetic acid (IAA), α-naphthalene acetic acid (NAA), 2,4-dichlorophenoxyacetic acid (2,4-d), thidiazuron (TDZ), 6-benzyl aminopurine (BAP) and kinetin (Kn) both singly and in combination incorporated in the MS medium were studied on growth and development of seedlings. It was observed that MS medium nourished with 15 μM each of BAP and NAA in combination was found to enhance shoot number and length, and root number and length in the seedlings. The rooted seedlings were successfully acclimatized.

The plant resources form an integral part of a huge inter-dependent system that encompasses the physical components and the biological community of life. These resources have enormous prospective benefits to humankind. The ever-increasing population and climate change over the years have contributed substantially to the pressure on plant resources leading to their decline or loss in nature. Hence, there is an immediate need to develop suitable conservation strategies for proper utilization and sustainability of these important resources.The plant resources form an integral part of a huge inter-dependent system that encompasses the physical components and the biological community of life. These resources have enormous prospective benefits to humankind. The ever-increasing population and climate change over the years have contributed substantially to the pressure on plant resources leading to their decline or loss in nature. Hence, there is an immediate need to develop suitable conservation strategies for proper utilization and sustainability of these important resources.

An in vitro regeneration protocol was developed for Capsicum chinenseJacq. cv. Naga King Chili, a very pungent chili cultivar and an important horticultural crop of Nagaland (Northeast India). Maximum number of shoot (13 ± 0.70) was induced with bud-forming capacity (BFC) index of 10.8, by culturing nodal segments in Murashige and Skoog (MS) medium supplemented with 18.16 μM Thidiazuron (TDZ) followed by 35.52 μM 6-benzylaminopurine (BAP). Using shoot tips as explants, multiple shoot (10 ± 0.37) (BFC 8.3) was also induced in MS medium fortified with either 18.16 μM TDZ or 35.52 μM BAP. Elongated shoots were best rooted in MS medium containing 5.70 μM indole-3-acetic acid (IAA). Rooted plantlets thus developed were hardened in 2–3 weeks time in plastic cups containing potting mixture of a 1:1 mix of soil and cow dung manure and then subsequently transferred to earthen pots. The regenerated plants did not show any variation in the morphology and growth as compared to the parent plant.

AbstractKaryo-morphological studies have been carried out in three different species of the genus Cymbidiumfrom North-eastern India. The somatic chromosome number (2n = 40) has been recorded in all the three species with distinct inter-specifi c variation in the arm ratio of few homologous pairs in the complements. The karyotypes of the species were more or less symmetrical. The significance of karyotypic variation in speciation of the genus Cymbidiumhas been discussed.

Abstract: Vitrification methods are convenient for cryopreserving plant specimens, as the specimens are plunged directly into liquid nitrogen (LN) from ambient temperatures. However, tissues and species with poor survival are still not uncommon. The development of vitrification solutions with high survival that cover a range of materials is important. We attempted to develop new vitrification solutions using bromegrass cells and found that VSL, comprising 20% (w/v) glycerol, 30% (w/v) ethylene glycol, 5% (w/v) sucrose, 10% (w/v) DMSO and 10 mM CaCl2, gave the highest survival following cryopreservation, as determined by fluorescein diacetate staining. However, the cryopreserved cells showed little regrowth, for unknown reasons. To check its applicability, VSL was used to cryopreserve gentian axillary buds and the performance was compared with those of conventional vitrification solutions. Excised gentian stem segments with axillary buds (shoot apices) were two-step precultured with sucrose to induce osmotic tolerance prior to cryopreservation. Gentian axillary buds cryopreserved using VSL following the appropriate preculturing approach exhibited 78% survival (determined by the regrowth capacity), which was comparable to PVS2 and PVS1 and far better than PVS3. VSL had a wider optimal incubation time (20–45 min) than PVS2 and was more suitable for cryopreserving gentian buds. The optimal duration of the first step of the preculture was 7–11 days, and preculturing with sucrose and glucose gave a much higher survival than fructose and maltose. VSL was able to vitrify during cooling to LN temperatures, as glass transition and devitrification points were detected in the warming profiles from differential scanning calorimetry. VSL and its derivative, VSL+, seem to have the potential to be good alternatives to PVS2 for the cryopreservation of some materials, as exemplified by gentian buds.

Callus cultures of Coptis teeta were established from hypocotyl segments (excised from aseptically germinating seeds) on Murashige and Skoog (MS) medium containing 2,4-dichlorophenoxyacetic acid (2,4-D) and kinetin. Microshoots were produced within 6–7 weeks of subculturing this callus in 1/2 MS nutrient medium supplemented with kinetin alone. Excised microshoots were rooted in 1/2 MS nutrient medium containing indolebutyric acid (IBA). The complete plantlets were hardened and established.