Cryopreservation of Dendrobium cruentum Rchb. f. Seeds by  D Cryo-plate and V Cryo-plate Techniques

Dendrobium cruentum Rchb. f. is a native Thai orchid species that has faced extinction because of its attractive characteristics. Consequently, conservation of this species is urgently needed. In this study, cryopreservation technique was applied to D. cruentum Rchb. f. seeds for long-term conservation. A successful protocol for D. cruentum Rchb. f. seed cryopreservation was developed by using D cryo-plate and V cryo-plate techniques. Seed viability was tested by TCC solution and 93.8 % of dyed seeds were shown. For cryo-plate technique, seeds were encapsulated over the cryo-plate by using 2 % (w/v) sodium alginate and polymerized with 100 mM CaCl2. Encapsulated seeds were desiccated by using a laminar airflow and PVS2 solution treatment with the same exposure time (0, 30, 60, 90, and 120 min). After cryopreservation, encapsulated seeds were cultured on modified VW agar medium. From the results, the maximum germination and regrowth percentage were observed; D cryo-plate technique with 60 min of dehydration time gave the highest germination (68.9 %) and regrowth (57.8 %). Thus, the excess of dehydration may cause the reduction of germination and plant regeneration. In conclusion, D cryo-plate technique proved to be appropriate for D. cruentum Rchb. f. seed cryopreservation.

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Efficiency of cryoprotectors for cryopreservation of two orchid species from Americas

Rodriguésia ◽

10.1590/2175-7860202172123 ◽

2021 ◽

Vol 72 ◽

Author(s):

Suzana Targanski Sajovic Pereira ◽

Wagner Aparecido Vendrame ◽

Kathia Fernandes Lopes Pivetta ◽

José Carlos Sorgato ◽

Ricardo Tadeu de Faria

Keyword(s):

Exposure Time ◽

Cold Storage ◽

Normal Development ◽

Seed Viability ◽

Orchid Species ◽

Successful Recovery ◽

Cryoprotective Solution ◽

Species Specific ◽

Faster Development

Abstract The objective of this study was to evaluate the efficiency of cryoprotective solution (PVS2) combined with phloroglucinol for the cryopreservation of seeds of two orchid species, Encyclia cordigera and Epidendrum ciliare. Seeds of Encyclia cordigera had 91.03% initial viability and 91.99% germination. The treatment of the seeds with PVS2 at 0 °C with 1% phloroglucinol for 60 min returned 93.79% viability and 91.01% germination after recovery from LN, consequently resulting in faster development of protocorms. For Epidendrum ciliare, seed viability was 85.65% and germination was 85.90%. Seed exposure to the PVS2 at 0 °C with 1% phloroglucinol for 180 min showed viability of 39.23% and germination of 37.88%. Despite lower germination, 78.90% of the protocorms reached stage P3 of development, when evaluated 45 days after sowing, not significantly different from the control 1, and showed normal development. These results indicate that PVS2 cryoprotective solution is efficient when combined with phloroglucinol for the cryopreservation and successful recovery of seeds of Encyclia cordigera and Epidendrum ciliare. The present study also indicates that response to cryopreservation and success of recovery after cold storage is species-specific and requires adjustments in exposure time to PVS2 at 0 °C prior to immersion in LN.

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Cryopreservation of Fagus crenata seeds: estimation of optimum moisture content for maintenance of seed viability by Bayesian modeling

Canadian Journal of Forest Research ◽

10.1139/cjfr-2017-0286 ◽

2018 ◽

Vol 48 (2) ◽

pp. 192-196 ◽

Cited By ~ 2

Author(s):

Keita Endoh ◽

Michinari Matsushita ◽

Megumi K. Kimura ◽

So Hanaoka ◽

Yuko Kurita ◽

...

Keyword(s):

Moisture Content ◽

Seed Viability ◽

Fagus Crenata ◽

Natural Forests ◽

Fagus Crenata Blume ◽

Long Term Storage ◽

High Viability ◽

Term Storage ◽

Seed Cryopreservation

Fagus crenata Blume is an important forestry tree species that plays a key biological role in natural forests. Because F. crenata forests are declining under global warming, the conservation of seed resources is necessary to maintain sustainable regeneration. We examined the capability of seed cryopreservation to achieve semi-permanent preservation of the F. crenata genetic resource. Seeds at 7%–26% moisture content (MC) exhibited greater than 64% viability, with developing radicles growing at 22 °C in 16 h photoperiods following chilling at 2 °C for 2 months. These seeds were then stored cryogenically at –170 °C for 6 months; cryopreservation at 26% MC reduced seed viability to 12%, whereas dry seeds (7%–14% MC) maintained viability and were comparable with seeds that had neither been dried nor cryopreserved. Drying seeds to 6% MC reduced viability to 47%; following cryopreservation, the viability of these seeds with such a low MC was 36%. Using a Bayesian model, we then determined that the optimal range of MC for the cryopreservation of F. crenata seeds was 9%–12%. We conclude that cryopreservation is feasible for the long-term storage of F. crenata seeds, drying of the seeds to the range of optimal MC retains high viability during cryogenic storage.

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Barley Seeds miRNome Stability during Long-Term Storage and Aging

International Journal of Molecular Sciences ◽

10.3390/ijms22094315 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4315

Author(s):

Marta Puchta ◽

Jolanta Groszyk ◽

Magdalena Małecka ◽

Marek D. Koter ◽

Maciej Niedzielski ◽

...

Keyword(s):

Seed Viability ◽

Small Rna Sequencing ◽

The Novel ◽

Seed Aging ◽

Long Term Storage ◽

Novel Mirna ◽

Complex Biological Process ◽

Almost All ◽

Term Storage

Seed aging is a complex biological process that has been attracting scientists’ attention for many years. High-throughput small RNA sequencing was applied to examine microRNAs contribution in barley seeds senescence. Unique samples of seeds that, despite having the same genetic makeup, differed in viability after over 45 years of storage in a dry state were investigated. In total, 61 known and 81 novel miRNA were identified in dry seeds. The highest level of expression was found in four conserved miRNA families, i.e., miR159, miR156, miR166, and miR168. However, the most astonishing result was the lack of significant differences in the level of almost all miRNAs in seed samples with significantly different viability. This result reveals that miRNAs in dry seeds are extremely stable. This is also the first identified RNA fraction that is not deteriorating along with the loss of seed viability. Moreover, the novel miRNA hvu-new41, with higher expression in seeds with the lowest viability as detected by RT-qPCR, has the potential to become an indicator of the decreasing viability of seeds during storage in a dry state.

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Impact of Prolonged Exposure of Eleven Years to Hot Seawater on the Degradation of a Thermoset Composite

Polymers ◽

10.3390/polym13132154 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2154

Author(s):

Amir Hussain Idrisi ◽

Abdel-Hamid I. Mourad ◽

Muhammad M. Sherif

Keyword(s):

Exposure Time ◽

Prolonged Exposure ◽

Mechanical Performance ◽

Matrix Cracking ◽

Pull Out ◽

Strength Based ◽

Different Temperatures ◽

River Line ◽

Composite Samples

This paper presents a long-term experimental investigation of E-glass/epoxy composites’ durability exposed to seawater at different temperatures. The thermoset composite samples were exposed to 23 °C, 45 °C and 65 °C seawater for a prolonged exposure time of 11 years. The mechanical performance as a function of exposure time was evaluated and a strength-based technique was used to assess the durability of the composites. The experimental results revealed that the tensile strength of E-glass/epoxy composite was reduced by 8.2%, 29.7%, and 54.4% after immersion in seawater for 11 years at 23 °C, 45 °C, and 65 °C, respectively. The prolonged immersion in seawater resulted in the plasticization and swelling in the composite. This accelerated the rate of debonding between the fibers and matrix. The failure analysis was conducted to investigate the failure mode of the samples. SEM micrographs illustrated a correlation between the fiber/matrix debonding, potholing, fiber pull-out, river line marks and matrix cracking with deterioration in the tensile characteristics of the thermoset composite.

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Continuous automatic measurement of rhythms in fungal respiration using a gas chromatograph

Canadian Journal of Botany ◽

10.1139/b73-087 ◽

1973 ◽

Vol 51 (4) ◽

pp. 701-710 ◽

Cited By ~ 5

Author(s):

Roger S. Smith

Keyword(s):

Carbon Dioxide ◽

Agar Medium ◽

Quantitative Measure ◽

Automatic Measurement ◽

Carbon Dioxide Production ◽

Chromatographic Technique ◽

Gas Chromatograph ◽

Growth Chambers ◽

Long Term Measurement

The long-term measurement of aerobic fungal respiration, both on an agar medium and on wood blocks, was possible using a gas-chromatographic technique for the detection of the carbon dioxide. This method was fully automated to analyze gas samples sequentially from eight or more growth chambers, after variable but determined time periods. It provided a precise quantitative measure of the respired carbon dioxide, presented both in the form of punched computer tape and normal printed teleprinter output. This apparatus worked continuously for several years without serious breakdown.The fungi Lentinus lepideus, Lenzites trabea, Poria monticola, and several strains of Coniophora puteana all showed a rhythm in their respiration which was not controlled by temperature or light. The magnitude and frequency of the rhythmical peaks in carbon dioxide production varied between fungi and, although there was considerable variation between different isolates of the same species, the separation of these species of fungi based on their different patterns of respiration was possible.

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Seed longevity of maize conserved under germplasm bank conditions for up to 60 years

Annals of Botany ◽

10.1093/aob/mcab009 ◽

2021 ◽

Author(s):

Filippo Guzzon ◽

Maraeva Gianella ◽

Jose Alejandro Velazquez Juarez ◽

Cesar Sanchez Cano ◽

Denise E Costich

Keyword(s):

Seed Germination ◽

Plant Genetic Resources ◽

Seed Viability ◽

Storage Conditions ◽

Seed Longevity ◽

Germplasm Bank ◽

Significant Difference ◽

Different Temperatures ◽

Germination Experiments

Abstract Background and Aims The long-term conservation of seeds of plant genetic resources is of key importance for food security and preservation of agrobiodiversity. Nevertheless, there is scarce information available about seed longevity of many crops under germplasm bank conditions. Methods Through germination experiments as well as the analysis of historical monitoring data, we studied the decline in viability manifested by 1000 maize (Zea mays subsp. mays) seed accessions conserved for an average of 48 years at the CIMMYT germplasm bank, the largest maize seedbank in the world, under two cold storage conditions: an active (–3 °C; intended for seed distribution) and a base conservation chamber (–15 °C; for long-term conservation). Key Results Seed lots stored in the active chamber had a significantly lower and more variable seed germination, averaging 81.4 %, as compared with the seed lots conserved in the base chamber, averaging 92.1 %. The average seed viability detected in this study was higher in comparison with that found in other seed longevity studies on maize conserved under similar conditions. A significant difference was detected in seed germination and longevity estimates (e.g. p85 and p50) among accessions. Correlating seed longevity with seed traits and passport data, grain type showed the strongest correlation, with flint varieties being longer lived than floury and dent types. Conclusions The more rapid loss of seed viability detected in the active chamber suggests that the seed conservation approach, based on the storage of the same seed accessions in two chambers with different temperatures, might be counterproductive for overall long-term conservation and that base conditions should be applied in both. The significant differences detected in seed longevity among accessions underscores that different viability monitoring and regeneration intervals should be applied to groups of accessions showing different longevity profiles.

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Effects of a long-term fire retardant chemical (Fire-Trol 934) on seed viability and germination of plants growing in a burned Mediterranean area

International Journal of Wildland Fire ◽

10.1071/wf06093 ◽

2007 ◽

Vol 16 (3) ◽

pp. 349 ◽

Cited By ~ 14

Author(s):

Belén Luna ◽

José M. Moreno ◽

Alberto Cruz ◽

Federico Fernández-González

Keyword(s):

Life Form ◽

Seed Viability ◽

Fire Retardant ◽

Mediterranean Area ◽

General Tendency ◽

Progressive Decrease ◽

Plant Groups ◽

Distribution Ranges ◽

High Concentrations

This work documents the effect of a common, long-term fire retardant chemical, Fire-Trol 934, on seed viability and germination of 36 plant species growing in a burned Mediterranean area, covering different life-form types, regenerative strategies and distribution ranges. Seeds were subjected to four treatments: control, and application of Fire-Trol 934 at concentrations of 0.02, 0.2 and 2%. Fire-Trol 934 significantly decreased both seed viability and germination in the group of species studied, which suggests that Fire-Trol 934 may be toxic for seeds, at least when applied at high concentrations. Whereas seed viability generally showed a progressive decrease with increased Fire-Trol 934 concentration, germination percentages generally increased when intermediate Fire-Trol 934 concentrations were used, but tended to be drastically reduced when seeds were exposed to the highest (2%) concentration. The reduction observed in germination at the highest Fire-Trol 934 concentration was greater than that observed in viability, which suggests that the effect of Fire-Trol 934 on seeds may not be lasting. Little differences in the response to Fire-Trol 934 emerged among plant groups, all of which followed the general tendency described above.

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Comparative Proteomics at the Critical Node of Vigor Loss in Wheat Seeds Differing in Storability

Frontiers in Plant Science ◽

10.3389/fpls.2021.707184 ◽

2021 ◽

Vol 12 ◽

Author(s):

Xiuling Chen ◽

Andreas Börner ◽

Xia Xin ◽

Manuela Nagel ◽

Juanjuan He ◽

...

Keyword(s):

Seed Viability ◽

Storage Period ◽

Protein Translation ◽

Artificial Ageing ◽

Plateau Phase ◽

Cell Defense ◽

Critical Node ◽

Cytotoxic Compounds ◽

Wheat Seeds

The critical node (CN, 85% germination) of seed viability is an important threshold for seed regeneration decisions after long-term conservation. Dependent on the germplasm, the storage period until CN is reached varies and information on the divergence of the proteomic profiles is limited. Therefore, the study aims to identify key proteins and mechanisms relevant for a long plateau phase and a late CN during artificial seed aging of wheat. Seeds of the storage-tolerant genotype (ST) TRI 23248, and the storage-sensitive genotype (SS) TRI 10230 were exposed to artificial ageing (AA) and extracted embryos of imbibed seeds were analyzed using an iTRAQ-based proteomic technique. ST and SS required AA for 24 and 18 days to reach the CN, respectively. Fifty-seven and 165 differentially abundant proteins (DAPs) were observed in the control and aged groups, respectively. Interestingly, a higher activity in metabolic processes, protein synthesis, transcription, cell growth/division, and signal transduction were already found in imbibed embryos of control ST seeds. After AA, 132 and 64 DAPs were accumulated in imbibed embryos of both aged ST and SS seeds, respectively, which were mainly associated with cell defense, rescue, and metabolism. Moreover, 78 DAPs of ST appeared before CN and were mainly enriched in biological pathways related to the maintenance of redox and carbon homeostasis and they presented a stronger protein translation ability. In contrast, in SS, only 3 DAPs appeared before CN and were enriched only in the structural constituents of the cytoskeleton. In conclusion, a longer span of plateau phase might be obtained in seeds when proteins indicate an intense stress response before CN and include the effective maintenance of cellular homeostasis, and avoidance of excess accumulation of cytotoxic compounds. Although key proteins, inherent factors and the precise regulatory mechanisms need to be further investigated, the found proteins may also have functional potential roles during long-term seed conservation.

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Mid storage seed hardening: a mechanical method to maintain seed viability during long term jute seed preservation

Plant Science Today ◽

10.14719/pst.2021.8.1.916 ◽

2021 ◽

Vol 8 (1) ◽

pp. 79-88

Author(s):

Md. Nasir Uddin ◽

S. M. Mahbub Ali ◽

Md. Abu Sadat ◽

Md Amazed Hossain Chowdhury ◽

Israt Jahan Mumu ◽

...

Keyword(s):

Crop Production ◽

Agricultural Sector ◽

Seed Viability ◽

Early Period ◽

Chemical Properties ◽

Seed Storage ◽

Germination Percentage ◽

Oil Degradation ◽

Hardening Treatment

Seed plays an important role in agricultural sector for both production and consumption purpose. Availability of vigour seed is one of the major constraints for maximizing crop production. However, healthy seed can also lose its viability during seed storage by changing different physio-chemical properties. Influence of environmental factors and seed containers during storage leading to seed deterioration. In this research, mid storage seed hardening treatment was applied in different aged seeds of jute species (C. Capsularis & C. olitorius) with two types of storage bags. Seed hardening treatment showed the less moisture content with better germination percentage compared to the untreated species of jute seeds. Seed packing in polythene bags during both short and long term seed storages had higher viable seeds compared to the cloth packing seeds. The effect of seed hardening treatment on seed oil content and pattern of oil degradation is distinct in early period of storage. The faster rate of oil degradation, soluble protein and free amino acids was found in seeds of un-treated stored seeds in cloth bag. Contrary, very slow rate of oil degradation was observed in harden seed and stored in polythene bag which indicated better storability of harden seeds.

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Effect of cooling rates of solution treatment on rejuvenation heat-treated microstructures of a cast nickel-based superalloy

Materials Testing ◽

10.1515/mt-2020-0016 ◽

2021 ◽

Vol 63 (2) ◽

pp. 105-112

Author(s):

Chuleeporn Paa-rai ◽

Gobboon Lothongkum ◽

Panyawat Wangyao

Keyword(s):

Solution Treatment ◽

Spherical Shape ◽

Irregular Shape ◽

Air Cooling ◽

Gamma Prime ◽

Nickel Based Superalloy ◽

Heat Treated ◽

Two Temperatures ◽

Cooling Media

Abstract IN-738 turbine blade samples, deteriorated after long term service at high temperatures, were solution heat-treated at two temperatures, 1398 K and 1473 K, for 7.2 ks. Subsequently, the samples were cooled down in different atmospheres, in air and in furnace, for the purpose of studying the effects of different cooling media (rates) on the restored microstructures. Following this, the samples were aged at 1118 K for 43.2 ks and 86.4 ks in order to determine the characteristic of re-precipitated gamma prime particles. A scanning electron microscope (SEM) and ImageJ analysis software were used. The results show that the cooling in air provided gamma prime particles re-precipitating in spherical shape while the cooling in a furnace resulted in coarse gamma prime particles re-precipitating in irregular shape. The samples solutionized at 1398 K for 7.2 ks cooled down in air and then aging at 1118 K provided bimodal microstructure, while the sample solutionized at 1473 K for 7.2 ks, followed by air cooling and aging at 1118 K generated unimodal γ’ precipitation in spherical shape. Cooling in a furnace provides coarse γ’ recipitated particles in more irregular shape for the both solutionizing temperatures studied here. Cooling in a furnace provides coarse γ’ precipitated particles in more irregular shape for the both solutionizing temperatures studied here.

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