Artificial Seeds Research Articles

Production of Artificial Seeds of Carica papaya L. var Eksotika

Artificial seed production technique for Carica papaya L. var Eksotika is considered as a valuable alternate technology of propagation. Limited availability of the elite genotypes apprehends the utility of the C. papaya L. var Eksotika plants, for industrial use and ecological improvement. Therefore, development of an efficient method for C. papaya L. var Eksotika artificial seeds production by encapsulation of micro shoots in sodium alginate matrix were produced. Artificial seeds of C. papaya L. var Eksotika were produced by encapsulated micro shoots of C. papaya L. varieties Eksotika propagated in vitro. The production of artificial plant seeds of this species offered ideal beads based upon stiffness, texture, size and shape of beads. It was found that 4% sodium alginate and harden in two hundred millimolar CaCl2.2H2O solution produced optimum beads with stiff, clear, round and homogeneous size for 30 minutes among the concentrations tested.

Not gone with the wind: Vegetation complexity increases seed retention during windy periods in the Argentine Semiarid Chaco

AbstractQuestionsWe experimentally studied whether different degrees of vegetation structural complexity, developed under different land‐use regimes, affected the retention of seeds in situ in the semiarid Chaco forest. We sought to answer the following questions: (a) Does vegetation complexity in interaction with climatic conditions affect seed retention on the soil surface? (b) Do seeds with contrasting traits show the same retention pattern?LocationChancaní, Northwestern Córdoba, Argentina.MethodsWe run a field experiment to test seed retention across 16 field sites differing in physiognomy and land‐use regime. We used artificial seeds with contrasting traits to simulate extreme morphologies found among dominant species of the Chaco forest (large‐flattened and small‐spherical seed types). We placed artificial seeds in 10 quadrats along a transect at each site and recorded the number of seeds retained after 25 days. We performed the experiment in the same season in two consecutive years. Through a Principal Component Analysis of a matrix of 320 survey plots by 6 structural variables, we extracted two major multivariate axes summarizing vegetation complexity.ResultsVegetation complexity was strongly related to land‐use regimes, and a more complex vegetation structure increased seed retention, particularly in the first year of the experiment, when wind velocity was twice the value of the historical mean. The same general retention pattern was observed for different seed types with contrasting size and shape, but the absolute amount of retention was lower for large‐flattened than small‐spherical seeds.ConclusionVegetation complexity interacting with variable climatic conditions ‐especially wind velocity‐ and seed morphology increased seed retention on the soil surface. Because seed dynamics is known to play an essential role in vegetation recovery, manipulation of soil cover should be a key factor in vegetation resilience in these systems.

Gut bacteria of the cowpea beetle mediate its resistance to dichlorvos and susceptibility to Lippia adoensis essential oil

Bacteria inhabiting the gut of insects provide many benefits to their hosts, such as aiding in food digestion, reproduction, and immunity, tissue homeostasis, adaptation to environment and resistance to pathogen and pesticides. The cowpea beetle, Callosobruchus maculatus, is a serious cosmopolitan pest of pulses. This beetle has lent itself as a guinea pig for several ecological studies. It harbors a consortium of bacterial communities in its gut, but the evidence for their role in its physiology is fragmentary. In this work, we hypothesized that gut microbiota mediates C. maculatus resistance to dichlorvos (DDVP or O,O-dimethyl O-2,2-dichlorovinylphosphate) and represent the target of Lippia adoensis (Gambian Tea Bush) essential oil (EO). Symbiotic and aposymbiotic beetles were exposed to artificial cowpea seeds earlier treated with DDVP or EO. Adult mortality and changes in gut bacterial community composition and abundance were examined at F1 and F5 generations. The susceptibility of experimental beetles to DDVP was significantly affected by their symbiotic status. The adult mortality decreased across generations in DDVP treatments, and remained significantly higher in aposymbiotic groups. In EO treatments, the mortality was consistent irrespective of symbiotic status and experimental generations. When compared to DDVP and the Control, EO treatments had significantly lower bacterial richness and diversity, as well as lower abundance of Proteobacteria, Firmicutes, and Bacteroidetes. These results support our hypothesis and describe the responses of gut microbial communities to pesticide treatments. This could be of interest for developing new management strategies of this pest.

Dung beetle activity affects rain forest seed bank dynamics and seedling establishment

AbstractDung beetles relocate vertebrate feces under the soil surface, and this behavior has many ecological consequences. In tropical forests, for example, seeds defecated by mammals that are subsequently buried by dung beetles are less likely to suffer predation. While the effects of dung beetles on the fate of defecated seeds have been relatively well studied, their effect on seeds already buried in the soil has not. To contribute to fill this gap, we designed a study with three objectives: (a) Describe the vertical re‐distribution of soil seeds that occurs due to dung beetle activity; (b) Determine if beetle activity favors establishment of seedlings from the soil seed bank; and (c) Determine if the effect of dung beetles is stronger in sites of recurrent mammal defecation. We carried out three complementary field experiments, one with artificial seeds (plastic beads) of three sizes buried at known depths, one with two species of seeds buried at those same depths, and one with the natural soil seed bank in sites of single vs. recurrent defecation. Buried beads were moved by dung beetles along the vertical axis, both upwards (9.5%) and downwards (11.5%); smaller beads were more frequently moved downwards while the contrary occurred for larger beads. Dung beetle activity caused an increase in seedling establishment, both from experimentally buried seeds and from the natural seed bank. Defecation recurrence had no effect on seedling establishment. We conclude that dung beetle activity affects seed bank dynamics with important consequences for seedling establishment in tropical forests.Abstract in Spanish is available with online material.

Long-term outdoor lysimeter study with cerium dioxide nanomaterial

Fate and impact of cerium dioxide nanomaterials (CeO2 NM) in soil remains uncertain. Most of the recent environmental studies used high doses of CeO2 NM in short-term laboratory experiments and stated soil as large sink for NM. Recent studies covering the life cycle of plants found evidence for particle uptake in crop plants, and triggered concern about NM entering the food chain. Here, we present a 25 months outdoor lysimeter study that investigates the translocation, biological impact, and transformation of CeO2 NM in soils cultivated with different crops (wheat (Triticum aestivum L.), canola (Brassica napus L.), and barley (Hordeum vulgare L.)). Low doses of CeO2 NM (NM-212, 10 and 50 mg CeO2 NM kg−1 soil) were applied to a Cambisol by sewage sludge or artificial rainwater. To simulate ploughing, the CeO2 NM was mixed into the first 20 cm of the lysimeter soil. Three weeks after the NM application by sewage sludge and five days after the latest NM application by artificial rainwater wheat seeds were sown.We found no vertical Ce translocation to deeper soil layers as well as negligible release of Ce into percolating water, confirming that soil is a sink for CeO2 NM. Furthermore, no inhibition of the NM sensitive ammonium oxidizing bacteria (AOB) was observed which implies a low bioavailability of CeO2 NM in soil. The detected Ce root uptake for canola (Ce < 35.7 mg kg−1) and barley (Ce < 61.8 mg kg−1) indicates that physico-chemical conditions in the rhizosphere or the aging of the NM in soil can remobilize the applied CeO2 NM to some extent. One can speculate that the obtained reduction of Ce4+ to Ce3+ (≈ 50% after 25 months) was coupled to different conditions (ionic strength, pH, water content, soil organic matter content) in the rhizosphere and necessary for the root accumulation of Ce.Due to negligible mobility in the soil-water interface, as well as non-toxicity to AOB, the environmental risk of the tested CeO2 NM appears to be low, compared to other highly mobile emergent pollutants. Nonetheless, further long-term investigations need to focus on the speciation and localization of NM in plants to clarify uptake and impact of NM to crops.

Deciphering seed dispersal decisions: Size, not tannin content, drives seed fate and survival in a tropical forest

AbstractScatter‐hoarding animals can dramatically affect plant survival by depositing seeds in favorable microhabitats away from parent plants (seed dispersal) and by consuming seeds (seed predation). By understanding how scatter hoarders make seed dispersal decisions, we can infer how different plant chemical defenses or seed set strategies may influence seed survival and, ultimately, plant recruitment. We used a wild population of Central American agoutis, Dasyprocta punctata, to experimentally test how seed chemistry and size influence seed fates in a tropical premontane wet forest in Costa Rica. We hypothesized that seeds perceived by agoutis to be very valuable (large, non‐toxic seeds) would be taken far from sources and preferentially cached over less valuable (small, toxic) seeds. Using artificial seeds created from baked polymer clay and peanuts, we manipulated seed chemistry (0%, 2%, 15% tannic acid) and size (4, 14, 24 g) in fully factorial paired‐choice field experiments. We tracked the fates of individually numbered thread‐marked seeds in space and time. There was no difference in the handling, regardless of size, of non‐toxic and toxic seeds by agoutis. Large (24 g) seeds were moved farthest and preferentially hoarded by agoutis, whereas small (4 g) seeds were mostly eaten in situ. By experimentally manipulating seed chemistry and size with a high degree of replication using artificial seeds in the field, we have determined how these plant functional traits affect agouti seed dispersal decisions, with implications for plant propagation and the evolution of seed size.

Biotechnological technique for improvement of ornamental crops

Plant biotechnology plays an important role in mass production of improved crop varieties as well as their genetic improvement. It develops business processes and products, using recombinant DNA, gene transfer, embryo manipulation, plant regeneration, cell culture, monoclonal antibodies and bio-processed engineering, and biologically active substances such as food additives, dyes, pharmaceuticals, Helps in the production of bio-. Pesticides for the benefit of man and society. The development of techniques of molecular classification through RAPD and RFLP in genomic analysis and classification has opened up new options for germplasm characterization of ornamental plants such as roses, haptiolas, orchids, ornamental pods, anthurium, gerbera, gulgenvia and cut-offs. genetic engineering. Flowers (pink to white chrysanthemum) become easier. Transgenic plants are now available in haptiolus, petunia, rose, carnation, orchids, gerberas, etc. Bioreactor technology is the need of the hour which can cut the cost of production of plants. It is clear to develop new varieties produced by cross-hybridization, mutation breeding and reverse mutation or in combination through genetic mutations. Secondary metabolites from cell culture have been established for the synthesis of codine (Papaversomniferum), quinine (Cinchona liturgiana), pyrethrin (Crescentheim urn cineraphyrium), taxol (Taxisbactata), rutculin (Rata spans..) and bain and papain. Somatic embryogenesis is a powerful tool for the improvement of jewelery, not only in relation to the spread of clots, but also for other biotechnological applications. It has been successfully used in crop improvement, such as Enthurium, Alstroemeria, Hadiolus, Iris, Lilium etc. Artificial (encapsulated) seeds contain somatic embryos, which are covered with a protected gel, also known as somatic embryogenesis. Ovule culture is now applied in Freesia for the production of embryonic culture and interspecific hybrids in Alstroemeria, in Alstroemeria and Cyclamen. Thus, it is clear that the application of various strategies to biotechnological approaches offers immense opportunities for improvement in ornamental plants.

Effects of seed traits and seed production on the seed predation and dispersal behavior of rodents.

To deeply understand the foraging behavioral strategies of the rodents in response to seeds of different sizes and tannin contents under different seed densities and its relationship with plant regeneration, field experiments were conducted to explore the effects of artificial seeds of different sizes (large and small) and tannin (T) contents (0%T, 2%T, 8%T, and 15%T) on seed predation and dispersal behavior of rodents during simulated non-mast and mast seeding year in Larix principis-rupprechtii plantation of Liupan Mountains in Ningxia. The results showed that seeds were consumed rapidly by rodents in non-mast seeding year but relatively slow in mast seeding year. No significant difference of in situ predation rate (ISPR) was observed between non-mast and mast seeding year. The predation rates of seeds after dispersal (PRAD) by rodents in non-mast year were significantly higher than those in mast year, while the hoarding rate of seed after dispersal (HRAD) of the former was significantly lower than the latter. Both seed predation distance after dispersal (PDAD) and hoarding distance after dispersal (HDAD) by rodents in non-mast year were substantially higher than those in mast year. In non-mast year, both PDAD and HDAD of large seeds were longer than those of small seeds. Significant difference of the former was observed between large and small seeds for all tannin content seeds, but significant difference of the latter between large and small seeds was detected only for seeds of 2% and 15% tannin. In mast year, significant difference of PDADs and HDADs between large and small seeds was found in all other seeds of tannin contents except for 0% Tannin seeds. The ISPR maximized in medium tannin seeds and minimized in high tannin seeds. Maximums of PRAD were observed in high tannin seeds in non-mast year and 0% tannin seeds in mast year respectively. High tannin seeds had the highest HRAD while medium tannin seeds had the lowest HRAD in both mast and non-mast year. Our results suggested that mast seeding year could delay the seed consumption rate of rodents and increase the HRAD, but reduce the dispersal distance. Hoarding preference of the rodents on large seeds was demonstrated in both mast and non-mast years and the dispersal distance of large seeds was longer than those of small ones. It is probably that rodents prefer to predate in situ seeds of medium tannin and disperse high tannin seeds during both mast and non-mast years.

Conservation impacts of commercial cultivation of endangered and overharvested plants

Overharvesting is one of the greatest threats to species survival. Farming overharvested species is a conservation strategy that can meet growing market demand and conserve wild populations of the target species. This strategy is compatible with the international community's desire to uphold the right of local communities to use biological resources to support their livelihoods. However, studies investigating whether farming can alleviate poaching pressure have focused almost exclusively on animals. To address the shortfall in plant-focused studies, we compiled information on commercial cultivation of threatened plants to assess its conservation benefits. Because China's rising middle class has rapidly intensified demand for wildlife products, we searched the scientific literature published in Chinese (China National Knowledge Infrastructure and Baidu) and in English. We found 32 reports that contained data on 193 internationally or nationally threatened plant species that were under commercial cultivation. These reports showed that cultivations of 82% of the 193 species were sustained by collecting whole plants from the wild periodically or continuously. Although based on a small sample size, species that were maintained in cultivation only through artificial propagation or seeds collected in the wild were likely associated with a reported reduction in wild harvesting of whole plants. Even so, results of correlation analyses suggested that production system, scale, and when a species began being cultivated had little effect on conservation status of the species, either globally or in China. However, species brought into cultivation relatively recently and on a smaller scale were more likely to have undergone a reduction in collecting pressure. Farming of nonmedicinal plants was most problematic for species conservation because wild plants were laundered (i.e., sold as cultivated plants). For effective conservation, policy to guide cultivation operations based on the target species' biological characteristics, cultural significance, market demand, and conservation status is needed.

Plant regeneration of Nerium oleander L. from alginate-encapsulated shoot explants after short-term cold storage

ABSTRACT In this study, an efficient protocol for the regeneration of encapsulated explants of oleander (Nerium oleander L.) has been developed. Shoot tips and 1st nodal segments below the shoot tip, from in vitro-derived oleander microshoots, were encapsulated in 2.5% sodium alginate prepared in liquid MS sucrose-free nutrient medium and hardened in 50 mM of calcium chloride producing solid beads, uniform in shape. These artificial seeds, irrespective of their maintenance under light or in darkness, germinated at frequencies of 38.8–42.2%, producing 3.0–3.3 microshoots per bead. In the case of using 100 mM of calcium chloride for hardening, the beads were firm, of uniform globular shape and suitable for handling, exhibiting a germination response of 68.9%. Encapsulated shoot tip explants, following storage at 4°C for 8 weeks, exhibited a higher regeneration response (60.0%) than non-encapsulated similar explants stored under the same conditions (11.1%). Microshoots, excised from cold-stored encapsulated explants after germination, rooted easily in agar-solidified MS medium with 2 μΜ IBA and after their transplantation into a peat-perlite substrate (3:1, v/v), were acclimatised successfully and established in the greenhouse with minimal losses. The present encapsulation procedure could be applied as an alternative method of micropropagation of desirable elite clones of oleander.

Imbibition in plant seeds

We describe imbibition in real and artificial plant seeds, using a combination of experiments and theory. In both systems, our experiments demonstrate that liquid permeates the substrate at a rate which decreases gradually over time. Tomographic imaging of soy seeds is used to confirmed this by observation of the permeating liquid using an iodine stain. To rationalize the experimental data, we propose a model based on capillary action which predicts the temporal evolution of the radius of the wet front and the seed mass. The depth of the wetting front initially evolves as $t^{1/2}$ in accord with the Lucas-Washburn law. At later times, when the sphere is almost completely filled, the front radius scales as $(1-t/t_{\text{max}})^{1/2}$ where $t_{\text{max}}$ is the time required to complete imbibition. The data obtained on both natural and artificial seeds collapse onto a single curve that agrees well with our model, suggesting that capillary phenomena contribute to moisture uptake in soy seeds.

In vitro regeneration, production, and storage of artificial seeds in Ceropegia barnesii, an endangered plant

Approaches for in vitro regeneration and fabrication of synthetic seeds were formulated to support restoration in the wild and genetic manipulation of Ceropegia barnesii (categorized as endemic and endangered). MS medium augmented with 4 mg L−1 benzyl adenine was most advantageous for the production of multiple shoots from nodal explants. Fabrication of synthetic seeds was accomplished by sodium alginate encapsulation of nodes from microshoots. The most favorable medium combination for the induction of multiple shoots from synthetic seeds was MS medium complemented with 4 mg L−1 benzyl adenine and 1 mg L−1 gibberelic acid. Following root induction promoted by half strength MS basal medium augmented with indolebutyric acid, multiple shoots were subjected to hardening. Influence of vesicular-arbuscular mycorrhizal fungi on the hardening trials was investigated and it was observed that dual inoculation of Glomus aggregatum and G. intraradices enhanced the survival rate. The encapsulated nodes of C. barnesii were tested for their capability to endure different temperatures during storage and the optimal temperature for storage was found to be 4°C. A methodology for initiation of somatic embryogenesis from C. barnesii is also reported here, but embryos could not be induced to develop further. The micropropagated plants were reintroduced in to their natural habitat. This is the first report on micropropagation of C. barnesii.

A New Protocol Using Artificial Seeds to Evaluate Dietary Preferences of Harvester Ants in Semi-arid Environments

The preferences of seed intake by harvester ants (Pogonomyrmex spp.) have been debated for a long time, mainly due the lack of repeatable methods to draw clear conclusions. However, several characteristics of the food resource are well recognized as the drivers of such selective predation. For instance, resource quality (i.e., availability of carbohydrates, lipids, and proteins) is one factor that could explain the observed foraging patterns of Pogonomyrmex species. In this sense, experimental approaches using artificial resources (e.g., synthetic seeds/diaspores) have provided an useful and alternative tool to study ant’s food foraging behavior. Therefore, it is expected that the use of artificial seeds also could offer a versatile way to assess the influence of resource quality exert on the resource selection by harvester ants. On the other hand, empirical experiments involving harvester ants and artificial seeds are still rare in the literature and it is not known if such methodology is efficient with different Pogonomyrmex species. In this study carried out in a Neotropical arid environment of central Mexico, we tested a simple but fundamental question: Do harvester ants (Pogonomyrmex barbatus) predate artificial seeds with manipulated nutrient content (lipids and proteins) in the field? We found that the proportion of native seeds removed was lower than the proportion of artificial seeds removed. However, we found no difference between the removal of artificial seeds containing only lipids and the seeds containing lipids + proteins. These findings indicate that the artificial seeds synthesized by us could be an effective method to test different ecological hypothesis involving harvester ants. Moreover, our empirical experiment offers a benchmark to study the influence of resource quality on the food foraging behavior of harvester ants in Neotropical arid environments.

Seed removal by ants in Brazilian savanna: optimizing fieldwork

There has been an increase in the number of studies using seed removal by ants to evaluate ecosystem functioning; however, these studies encompassed varying time periods and used different types of seeds. Therefore, our aim was to evaluate differences in the proportion of seeds removed by ants in impacted and non-impacted sites in Brazilian savanna. Furthermore, we evaluated seed removal (1) during the morning and after a 24h period of seed exposure and (2) using natural and artificial seeds (manipulated resource to resemble natural seeds). The proportion of seeds removed was higher after the 24h exposure period (artificial seeds) regardless of site status, and more artificial seeds were removed than natural seeds. Our recommendations regarding sampling period depend on whether evaluating impacted or non-impacted sites. Although seed removal was greater after 24h in both impacted and non-impacted sites, we suggest that research evaluating the proportion of seeds removed in non-impacted sites should be performed only in the morning period to optimize the sampling time (removal of 60% during this period). When the aim is to compare non-impacted and impacted sites, we suggest evaluating after 24h of exposure, since the impacted sites experienced a higher proportion of seed removal during the afternoon and/or night time periods. Furthermore, we recommend the use of artificial seeds because they are easier to obtain and manipulate, and allow us to do comparisons between studies at different regions. We consider these findings an important first step towards standardizing future research on seed removal in Brazilian savannas by facilitating fieldwork and allowing comparisons to be made among different studies.

Sugar Beet Artificial Seeds an Overview

Artificial seed propagation of crops broadens the horizon of plant biotechnology and farming. The technology offers techniques for micropropagulated seed analogs such as axillary leaves, embryogenic calli, somatic embryos, apical shoot tips, and protocorm-like organs. Micropropagules are embedded in gelling medium and carboxyl methyl cellulose active coatings. A variety of plant species, such as mulberry, sandalwood, cardamom, banana, sugar beet, maize, and relative, have recorded encapsulation of micro shoots and somatic embryos and subsequent recovery of full plantlets. This knowledge has shown that artificial seed manufacturing is possibly helpful for the propagation of economically significant species ' inferior hybrids on a big scale. Artificial seed development can only succeed with effective upstream manufacturing of micropropagules and downstream germination procedures for an elevated proportion of plant regeneration as one of the significant value-added plant tissue culture goods. Different micropropagules were regarded for the manufacturing of artificial seeds; however, mostly favored were somatic embryos and axillary stem buds. As micropropagules, somatic embryos were used to create artificial seeds in a wide range of fruit and plant organisms, which include Daucus carota, Picea abies, Arachis hypogaea, Medicago sativa, Psidium guajava, and Vitis vinifera. The review illustrated the concept of synthetic seeds and encapsulation procedure of sugar beet

Nutrient alginate encapsulation of nodal segments of Althaea officinalis L., for short-term conservation and germplasm exchange

In the present study, an alternate method for germplasm storage in the form of artificial seeds was standardized via nodal explants excised from in vitro proliferated shoots. The explants were encapsulated using sodium alginate and calcium chloride as gelling matrix. For development of root along with shoot, excised nodal segments were pretreated with ½ MS medium along with 20 μM IBA for 24 h and encapsulation was carried thereafter. Combination of 3% sodium alginate augmented with 100 mM CaCl2.2H2O was found appropriate for the formation of clear and uniform beads and subsequent conversion of encapsulated nodal segments into plantlets. Maximum (66%) encapsulated nodal segments were converted into plantlets on MS medium supplemented with 7.5 μM BA and 0.5 μM NAA after eight weeks. Regeneration frequency of auxin-pretreated encapsulated and non-encapsulated nodal segments (stored at 4 ºC) was evaluated at different storage time (0 to 6 weeks). After four weeks of storage, encapsulated propagules exhibited highest conversion response on the optimized medium after eight weeks of culture. Plantlets were hardened and established with success in ex vitro conditions. Conversion of synthetic seeds into plantlets was observed when these were directly sown in autoclaved SoilriteTM (Keltech Energies, Bangalore, India).

Technological System Construction on Artificial Embryos Synchronization in Artificial Seeds Production of Pinellia ternata (Thunb.) Breit

Using Pinellia ternata leaf blade or petiole as explants, the singlefactor tests and orthogonal tests were used to research the effects from different explants and plant growth regulators to callus induction, cell micromasses suspension, cell micromass expansion and artificial embryo formation of P. ternata. Results showed that all induced calluses grew well and became looser using leaf blade explants and the combination of 2.0 mg/L 2,4-D and 1.5 mg/L BA or using petiole explants with 1.5 mg/L 2,4-D and 1.5 mg/L BA in the induction medium. The loose callus after three subculture with 2.0 mg/L 2,4-D and 1.5 mg/L 6-BA in medium was suitable materials to use as cell micromasses expansion culture. The expanded cell micromasses were differentiated and developed to form well synchronizing artificial embryo by suspension culture (suspension medium with 1.0 mg/L 2,4-D, 0.5 mg/L 6-BA, 40 g/L sucrose and 300 mg/L CH) and differentiation culture (differentiation medium with 0.5 mg/L 6-BA, 0.05 mg/L IBA, 10 g/L sucrose and 300 mg/L CH). This study successfully constructed and optimized the technology system of artificial embryos synchronization culture of P. ternate, it realized a breakthrough of the key technologies in artificial seeds production of P. ternata.

Efficient long-term conservation of Taraxacum pieninicum synthetic seeds in slow growth conditions

The aim of this paper was to develop a protocol for efficient storage of artificial seeds of Taraxacum pieninicum, critically endangered Asteraceae species. Storage under reduced light conditions or in the darkness was tested on a basis of synthetic seeds ability to conversion and post-storage regrowth of shoot tips. The results indicated that synseeds obtained from shoot tips of T. pieninicum can be stored at 4 °C even for 12 months without subculture. The light is a stress factor during storage what was manifested by numerous necrosis and decreased shoots ability to proliferate in optimal growth conditions in 1st subculture. Additionally our results showed that the storage does not produce genetic variation at the resolution provided by the flow cytometry and RAPD analysis.

Artificial Seeds (Principle, Aspects and Applications)

Artificial seeds are artificially encapsulated somatic embryos (usually) or other vegetative parts such as shoot buds, cell aggregates, auxiliary buds, or any other micropropagules which can be sown as a seed and converted into a plant under in vitro or in vivo conditions. An improved artificial seed production technique is considered a valuable alternate technology of propagation in many commercially important crops and a significant method for mass propagation of elite plant genotypes. The production of plant clones multiplied by tissue culture and distributed as artificial seeds could be a useful alternative to the costly F1 hybrids for different plant crops. The delivery of artificial seeds also facilitates issues such as undertaking several ways for scaling up in vitro cultures and acclimatization to ex vitro conditions. The development of an artificial seed technique also provides a great approach for the improvement of various plant species such as trees and crops.

Alginate-encapsulation, Short-term Storage and Plantlet Regeneration from Encapsulated Protocorm-like Bodies (PLBs) of Cymbidium finlaysonianum Lindl.: An Endangered Orchid of Thailand

Synthetic seed technology is becoming popular due to its wide application in germplasm conservation and for exchanges among countries in the floriculture trade. This method was used to study the bead formations and the conversion capabilities of Cymbidium finlaysonianum Lindl. For artificial seeds, new protocorm-like bodies (PLBs) (about 4 - 5 mm in diameter) of Cymbidium finlaysonianum Lindl. were isolated individually from 2-month-old proliferating PLB-clusters cultured in Vacin and Went (VW) liquid medium supplemented with 8.84 µM 6-benzyl-aminopurine (BAP). Different concentrations of sodium alginate (2, 3, 4 and 5 %) and calcium chloride (CaCl2.2H2O) (75, 85 and 100 mM) were tested to prepare bead formation. The ideal bead was obtained using 3 % sodium alginate and 100 mM CaCl2 for 30 min, resulting in uniform spherical beads. Effects of different media (full-strength MS, ½ MS or ¼ MS liquid medium with 3 % (w/v) sucrose) in gelling matrix on artificial seed germination were explored. Of the various gelling matrices for germination, the ¼ MS liquid medium was the most effective in terms of germination percentage (90 %) and germination date (28 days). Germination of the artificial seeds was observed within 28 - 56 days of formation on various gelling matrices. The effects of different storage conditions and intervals on conversion (into plantlets with shoot and root) ability of artificial seeds were determined. Among the 4 temperature regimes of storage (0 ± 2, 4 ± 2, 8 ± 2 and 25 ± 2 °C), artificial seeds were successfully stored at 8 ± 2 °C, till 105 days showed percentage of conversion frequency at 44.0 % when cultured on a VW medium supplemented with 2 % (w/v) sucrose with 0.2 % (w/v) activated charcoal. The complete plantlets derived from germinated-encapsulated PLBs showed 90 % survival rate during their gradual acclimatization to greenhouse conditions after transferal of rooted plantlets to sterilized coconut husks and irrigation with water twice a day for 3 months under 70 - 80 % relative humidity and about 12 h photoperiod. The highest percentage of plantlet survival recorded at 12 months after reestablishment in the forest was 75.8 %.