In Vitro Seed Germination of Kalmia latifolia L. Hybrids: A Means for Improving Germination and Speeding Up Breeding Cycle

Kalmia latifolia L. (mountain laurel), a member of Ericaceae, is a beautiful ornamental shrub native to the eastern United States. The plant is not common in the southeastern United States landscapes because of the limited heat tolerance of most commercial cultivars. Breeding of heat-tolerant cultivars can be achieved by cross hybridization, but is often challenged by low germination percentage, long germination time, and potential abortion of cross-hybridized seeds. We used in vitro seed germination to enhance germination and shorten germination time and investigated the appropriate collecting time, optimal basal medium, and pH for this approach. Collecting time affected in vitro seed germination, with more mature hybrid seeds [collected 4–5 months after pollination (MAP)] having higher germination rate (90% in 4 weeks) than the less mature seeds collected in 2 MAP (20% in 7 weeks). Seedlings from the mature seeds also produced two true leaves on average after 8 weeks of culture, whereas seedlings from the less mature seeds had no true leaves. Woody Plant Medium (WPM) better enhanced in vitro seed germination compared with Murashige and Skoog (MS) or Gamborg’s B5 (B5) medium. WPM yielded higher germination (98%) than MS (90%) and significantly greater total leaf area per seedling (67 mm3) than MS (50 mm3) and B5 (52 mm3) for seeds of ‘Firecracker’ × ‘Snowdrift’. Similar effects had been observed on seeds from ‘Little Linda’ × ‘Starburst’ and ‘Pristine’ × ‘Peppermint’. The pH ranging from 4.2 to 5.4 did not affect seed germination and seedling development of mountain laurel hybrids. Our protocol enabled early collection of mountain laurel hybrid seeds 1 month before their full maturation and permitted seeds to germinate in 4 weeks on WPM, which shortened the period from crossing to the seedling stage from up to 15 to 6 months and enhanced germination percentage from 30% to more than 90% compared with traditional seed germination. This protocol should be applied to promote the breeding and selection of new mountain laurel cultivars for the southeastern United States landscapes.

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Asymbiotic germination of Vanilla planifolia in relation to the timing of seed collection and seed pretreatments

Botanical Studies ◽

10.1186/s40529-021-00311-y ◽

2021 ◽

Vol 62 (1) ◽

Author(s):

Chih-Hsin Yeh ◽

Kai-Yi Chen ◽

Yung-I. Lee

Keyword(s):

Seed Germination ◽

Seed Development ◽

Seed Coat ◽

Germination Percentage ◽

Vanilla Planifolia ◽

Outermost Layer ◽

Seed Collection ◽

Seed Pretreatment ◽

Immature Seeds ◽

Mature Seeds

Abstract Background Vanilla planifolia is an important tropical orchid for production of natural vanilla flavor. Traditionally, V. planifolia is propagated by stem cuttings, which produces identical genotype that are sensitive to virulent pathogens. However, propagation with seed germination of V. planifolia is intricate and unstable because the seed coat is extremely hard with strong hydrophobic nature. A better understanding of seed development, especially the formation of impermeable seed coat would provide insights into seed propagation and conservation of genetic resources of Vanilla. Results We found that soaking mature seeds in 4% sodium hypochlorite solution from 75 to 90 min significantly increased germination. For the culture of immature seeds, the seed collection at 45 days after pollination (DAP) had the highest germination percentage. We then investigated the anatomical features during seed development that associated with the effect of seed pretreatment on raising seed germination percentage. The 45-DAP immature seeds have developed globular embryos and the thickened non-lignified cell wall at the outermost layer of the outer seed coat. Seeds at 60 DAP and subsequent stages germinated poorly. As the seed approached maturity, the cell wall of the outermost layer of the outer seed coat became lignified and finally compressed into a thick envelope at maturity. On toluidine blue O staining, the wall of outer seed coat stained greenish blue, indicating the presence of phenolic compounds. As well, on Nile red staining, a cuticular substance was detected in the surface wall of the embryo proper and the innermost wall of the inner seed coat. Conclusion We report a reliable protocol for seed pretreatment of mature seeds and for immature seeds culture based on a defined time schedule of V. plantifolia seed development. The window for successful germination of culturing immature seed was short. The quick accumulation of lignin, phenolics and/or phytomelanins in the seed coat may seriously inhibit seed germination after 45 DAP. As seeds matured, the thickened and lignified seed coat formed an impermeable envelope surrounding the embryo, which may play an important role in inducing dormancy. Further studies covering different maturity of green capsules are required to understand the optimal seed maturity and germination of seeds.

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Can Bulk and Nanosized Titanium Dioxide Particles Improve Seed Germination Features of Wheatgrass (Agropyron desertorum)

Notulae Scientia Biologicae ◽

10.15835/nsb539072 ◽

2013 ◽

Vol 5 (3) ◽

pp. 325-331 ◽

Cited By ~ 13

Author(s):

Reyhaneh AZIMI ◽

Hassan FEIZI ◽

Mohammad KHAJEH HOSSEINI

Keyword(s):

Seed Germination ◽

Germination Percentage ◽

Germination Time ◽

Positive Effects ◽

Tio2 Particles ◽

Nanosized Titanium Dioxide ◽

Mean Germination Time ◽

Germination Value ◽

Improve Seed Germination ◽

Nanosized Tio2

The goal of this study was to evaluate concentrations of nanosized TiO2 at 0, 5, 20, 40, 60 and 80 mg L-1 with bulk TiO2 for possible stimulatory effects on wheatgrass seed germination and early growth stage. After 14 days of seed incubation, germination percentage improved by 9% following exposure to 5 ppm nanosized TiO2 treatment comparing to control. Similar positive effects occurred in terms of germination value and mean daily germination. Application of bulk TiO2 particles in 80 ppm concentration greatly decreased the majority of studied traits. Therefore phytotoxicity effect observed on wheatgrass seedling by application of bulk TiO2 particles in 80 ppm concentration. Exposure of wheatgrass seeds to 5 ppm nanosized TiO2 and bulk and nanosized TiO2 at 60 ppm obtained the lowest mean germination time but higher concentrations did not improve mean germination time. In general, there was a positive response by wheatgrass seed to some concentrations of nanosized TiO2. Usage of nanoparicles in order to improve germination and establishment of range plant in adverse environments similar to rangeland could be possible.

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Asymbiotic Germination of Mature Seeds and the Seed Development of Vanilla Planifolia

10.21203/rs.3.rs-138206/v1 ◽

2021 ◽

Author(s):

Chih-Hsin Yeh ◽

Kai-Yi Chen ◽

Yung-I Lee

Keyword(s):

Cell Wall ◽

Seed Germination ◽

Seed Development ◽

Seed Coat ◽

Germination Percentage ◽

Vanilla Planifolia ◽

Outermost Layer ◽

Seed Pretreatment ◽

Immature Seeds ◽

Mature Seeds

Abstract Background: Vanilla planifolia is an important tropical orchid for production of natural vanilla flavor. Traditionally, V. planifolia is propagated by stem cuttings, which produces identical genotype that are sensitive to virulent pathogens. However, sexual propagation with seed germination of V. planifolia is intricate and unstable because of the extremely hard seed coat. A better understanding of seed development, especially the formation of impermeable seed coat would provide insights into seed propagation and conservation of genetic resources of Vanilla.Results: We found that soaking mature seeds in 4 % sodium hypochlorite solution from 75 to 90 min significantly increased germination and that immature seeds collected at 45 days after pollination (DAP) had the highest germination percentage. We then investigated the anatomical features during seed development that associated with the effect of seed pretreatment on raising seed germination percentage. The 45-DAP immature seeds have developed globular embryos and the thickened non-lignified cell wall at the outermost layer of the outer seed coat. After 60 DAP, the cell wall of the outermost layer of the outer seed coat became lignified and finally compressed into a thick envelope. These features matches the significant decreases of immature seed germination percentage after 60 DAP. Conclusion: We report a reliable protocol for seed pretreatment of mature seeds and for immature seeds culture based on a defined time schedule of V. plantifolia seed development. The thickened and lignified seed coat formed an impermeable envelope surrounding the embryo, and might play an important role in seed dormancy of V. plantifolia.

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LPIAT, a lyso-Phosphatidylinositol Acyltransferase, Modulates Seed Germination in Arabidopsis thaliana through PIP Signalling Pathways and is Involved in Hyperosmotic Response

International Journal of Molecular Sciences ◽

10.3390/ijms21051654 ◽

2020 ◽

Vol 21 (5) ◽

pp. 1654

Author(s):

Denis Coulon ◽

Lionel Faure ◽

Magali Grison ◽

Stéphanie Pascal ◽

Valérie Wattelet-Boyer ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Seed Germination ◽

Lipid Synthesis ◽

Strong Increase ◽

In Planta ◽

Acyltransferase Activity ◽

Chain Acyl ◽

Phosphatidylinositol Phosphates ◽

Mature Seeds

Lyso-lipid acyltransferases are enzymes involved in various processes such as lipid synthesis and remodelling. Here, we characterized the activity of an acyltransferase from Arabidopsis thaliana (LPIAT). In vitro, this protein, expressed in Escherichia coli membrane, displayed a 2-lyso-phosphatidylinositol acyltransferase activity with a specificity towards saturated long chain acyl CoAs (C16:0- and C18:0-CoAs), allowing the remodelling of phosphatidylinositol. In planta, LPIAT gene was expressed in mature seeds and very transiently during seed imbibition, mostly in aleurone-like layer cells. Whereas the disruption of this gene did not alter the lipid composition of seed, its overexpression in leaves promoted a strong increase in the phosphatidylinositol phosphates (PIP) level without affecting the PIP2 content. The spatial and temporal narrow expression of this gene as well as the modification of PIP metabolism led us to investigate its role in the control of seed germination. Seeds from the lpiat mutant germinated faster and were less sensitive to abscisic acid (ABA) than wild-type or overexpressing lines. We also showed that the protective effect of ABA on young seedlings against dryness was reduced for lpiat line. In addition, germination of lpiat mutant seeds was more sensitive to hyperosmotic stress. All these results suggest a link between phosphoinositides and ABA signalling in the control of seed germination

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Establishment of an EfficientIn VitroRegeneration Protocol for Rapid and Mass Propagation ofDendrobium chrysotoxumLindl. Using Seed Culture

The Scientific World JOURNAL ◽

10.1155/2014/740150 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 9

Author(s):

Potshangbam Nongdam ◽

Leimapokpam Tikendra

Keyword(s):

Acetic Acid ◽

Seed Germination ◽

Germination Percentage ◽

Naphthalene Acetic Acid ◽

Mass Propagation ◽

Asymbiotic Seed Germination ◽

Orchid Species ◽

Seed Culture ◽

Leaf Formation

An efficientin vitroregeneration protocol from seed culture has been established successfully forDendrobium chrysotoxum, an epiphytic orchid having tremendous ornamental and medicinal values. Seed germination response was encouraging in Mitra (M) medium enriched with different combinations of auxins and cytokinins. Medium supplemented with 0.4% activated charcoal (AC), 2 mg/L 6-benzyl amino purine (BAP), and 2 mg/L indole-3-acetic acid (IAA) produced best seed germination percentage in 2 weeks of culture. Incorporation of higher concentration of kinetin (KN) or BAP in combination with low auxin in medium induced pronounced shooting and leaf formation. Reduction in leaf development was evident when cytokinins exist singly in medium indicating synergistic effect of auxin and cytokinin in leaf induction. Presence of elevated level of indole-3-butyric acid (IBA) or 1-naphthalene acetic acid (NAA) with low cytokinin content in medium generated morein vitrorooting, though IBA was found to be more effective in rooting induction as compared to NAA. Thein vitroprotocol for asymbiotic seed germination developed from the present investigation can be used for rapid mass propagation of this highly importantDendrobiumorchid species.

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The influence of light spectra, UV-A, and growth regulators on the in vitro seed germination of Senecio cineraria DC.

Revista CERES ◽

10.1590/s0034-737x2010000500002 ◽

2010 ◽

Vol 57 (5) ◽

pp. 576-580 ◽

Cited By ~ 1

Author(s):

Cristiane Pimentel Victório ◽

Nina Cláudia Barbosa da Silva ◽

Maria Apparecida Esquibel ◽

Alice Sato

Keyword(s):

Seed Germination ◽

Growth Regulators ◽

White Light ◽

Germination Rate ◽

Germination Percentage ◽

Ms Medium ◽

In Vitro Germination ◽

Light Spectra ◽

Indole 3 Acetic Acid

This study was carried out to investigate the effects of light spectra, additional UV-A, and different growth regulators on the in vitro germination of Senecio cineraria DC. Seeds were surface-sterilized and inoculated in MS medium to evaluate the following light spectra: white, white plus UV-A, blue, green, red or darkness. The maximum germinability was obtained using MS0 medium under white light (30%) and MS + 0.3 mg L-1 GA3 in the absence of light (30.5%). S. cineraria seeds were indifferent to light. Blue and green lights inhibited germination. Different concentrations of gibberellic acid (GA3) (0.1; 0.4; 0.6; 0.8; 1.0 and 2.0 mg L-1) and indole-3-acetic acid IAA (0.1; 0.3 and 1.0 mg L-1) were evaluated under white light and darkness. No concentration of GA3 enhanced seed germination percentage under white light. However, when the seeds were maintained in darkness, GA3 improved germination responses in all tested concentrations, except at 1.0 mg L-1. Under white light, these concentrations also increased the germination time and reduced germination rate. Germination rate, under light or darkness, was lower using IAA compared with GA3.

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Seed Germination of Three Provenances of Rhododendron catawbiense: Influence of Light and Temperature

Journal of Environmental Horticulture ◽

10.24266/0738-2898-12.3.155 ◽

1994 ◽

Vol 12 (3) ◽

pp. 155-158 ◽

Cited By ~ 2

Author(s):

D. Bradley Rowe ◽

Frank A. Blazich ◽

Stuart L. Warren ◽

Thomas G. Ranney

Keyword(s):

United States ◽

Seed Germination ◽

Southeastern United States ◽

Total Darkness ◽

Temperature Requirements ◽

And Storage

Abstract Seeds of three provenances of Rhododendron catawbiense Michx. (Catawba rhododendron) were collected during Fall 1992 from the following localities in the southeastern United States: Cherokee Co., GA [34°20′N, 84°23′W, elev. = 320 m (1050 ft)], Johnston Co., NC [35°45′N, 78°12′W, elev. = 67 m (220 ft)], and Yancey Co., NC [35°45′N, 82°16′W, elev. = 1954 m (6410 ft)]. Following drying for 1 month and storage at 4°C (39°F), seeds were removed from storage in January 1993 and germinated at 25°C (77°F) or an 8/16 hr thermoperiod of 25°/15°C (77°/59°F) with daily photoperiods of 0, ½, 1, 2, 4, 8, 12, or 24 hr. Regardless of temperature and provenance, seeds required light for germination. Negligible germination for all provenances in total darkness was overcome by daily photoperiods as short as ½ hr. All provenances commenced germination earlier at 25°C (77°F) than at 25°/15°C (77°/59°F). Mean germination at day 24 for both temperature treatments and for all photoperiods with the exception of total darkness was 98%, 90%, and 80% for the Yancey, Johnston, and Cherokee Co. provenances respectively. Light and temperature requirements for seed germination of all provenances were similar, although seeds of the higher elevation, Yancey Co. provenance exhibited greater vigor; they germinated at a faster rate with greater cumulative germination.

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Pertumbuhan Biji Buah Naga (Hylocereus Polyrhizus) dengan Pemberian NAA dan Ekstrak Biji Jagung (Zea Mays) secara In Vitro

JURNAL BIOS LOGOS ◽

10.35799/jbl.11.1.2021.31340 ◽

2021 ◽

Vol 11 (1) ◽

pp. 47

Author(s):

Rizka Widasari ◽

Mukarlina Mukarlina ◽

Zulfa Zakiah

Keyword(s):

Seed Germination ◽

Growth Regulators ◽

Seed Extract ◽

Cultivated Plants ◽

Corn Seed ◽

Germination Time ◽

M 10 ◽

Dragon Fruit ◽

Hylocereus Polyrhizus

(Article History: Received 25 November 2020; Revised 5 January 2021; Accepted 10 February 2021) ABSTRAKBuah naga (Hylocereus polyrhizus) merupakan salah satu tanaman yang dibudidayakan di Indonesia. Perbanyakan bibit secara in vitro dengan teknologi kultur jaringan merupakan cara alternatif yang tepat untuk menyediakan bibit dalam waktu singkat dengan jumlah banyak. Penelitian ini bertujuan untuk menguji pengaruh dan konsentrasi terbaik penambahan ekstrak biji jagung dan NAA pada media tumbuh terhadap perkecambahan biji buah naga merah secara in vitro. Penelitian dilaksanakan di Laboratorium Kultur Jaringan, Jurusan Biologi, Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Tanjungpura Pontianak. Penelitian menggunakan Rancangan Acak Lengkap dengan 2 faktor perlakuan. Faktor pertama yaitu NAA dengan konsentrasi 0 M, 10-8M, 10-7M, dan 5x10-7M. Faktor kedua yaitu ekstrak biji jagung dengan konsentrasi 0%, 5%, 7,5%, dan 10%. Hasil penelitian menunjukkan pemberian ekstrak biji jagung tunggal, NAA tunggal dan kombinasi ekstrak biji jagung dan NAA memberikan pengaruh nyata terhadap tinggi planlet, namun tidak berpengaruh nyata terhadap persentase perkecambahan. Pemberian ekstrak biji jagung tunggal memberikan pengaruh nyata terhadap waktu berkecambah, sedangkan pemberian ekstrak biji jagung tunggal dan NAA tunggal berpengaruh nyata terhadap jumlah akar. Perlakuan 5.10-7M NAA + 7,5% ekstrak biji jagung menghasilkan pertumbuhan tinggi plantlet terbaik. Konsentrasi 7,5% ekstrak biji jagung merupakan konsentrasi terbaik waktu berkecambahan biji buah naga dan konsentrasi NAA tunggal 10-8M memberikan jumlah akar terbanyak.Kata Kunci: Pertumbuhan in vitro, Biji Buah Naga, Ekstrak Biji Jagung, NAA. ABSTRAKDragon fruit (Hylocereus polyrhizus) is one of the cultivated plants in Indonesia. In vitro propagation of seeds with the addition of synthetic growth regulators or from growth regulators from organic matter in the media, is an appropriate alternative way to provide large quantities of seeds in a short time. This study aims to determine the effect and the best effect of corn seed extract and NAA on growing media on in vitro red dragon fruit seed germination. The research was conducted at the Tissue Culture Laboratory, Department of Biology, Faculty of Mathematics and Natural Sciences, University of Tanjungpura Pontianak. The study used a completely randomized design with 2 treatment factors. The first factor is NAA with a concentration of 0 M, 10-8M, 10-7M, and 5x10-7M. The second factor is corn seed extract with a concentration of 0%, 5%, 7.5%, and 10%. The results showed that the administration of single corn seed extract, single NAA and a combination of corn seed extract and NAA had a significant effect on plantlet height, but did not significantly affect the germination percentage. The administration of single corn seed extract had a significant effect on germination time, while the administration of single corn seed extract and single NAA had a significant effect on the number of roots. The 5.10-7M NAA + 7.5% corn seed extract treatment resulted in the best plantlet height growth. The concentration of 7.5% corn seed extract was the best concentration for dragon fruit seed germination time and a single NAA concentration of 10-8M gave the highest number of roots.Keywords: In Vitro Growth, Dragon Fruit Seeds, Corn Seed Extract, NAA.

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Petroleum Ether Separation and Seedcoat Removal Enhance Seed Germination of a Casuarina equisetifolia L. × C. glauca Sieb. ex Spreng Hybrid

HortScience ◽

10.21273/hortsci.44.3.770 ◽

2009 ◽

Vol 44 (3) ◽

pp. 770-773

Author(s):

Xiuli Shen ◽

William S. Castle ◽

Frederick G. Gmitter

Keyword(s):

Seed Germination ◽

Petroleum Ether ◽

Germination Percentage ◽

Seed Sources ◽

Citrus Groves ◽

Casuarina Cunninghamiana ◽

Poor Seed ◽

Hybrid Seeds ◽

Two Temperatures ◽

Empty Seeds

Casuarina cunninghamiana Miq. is an introduced species to Florida that has potential as a windbreak plant to help manage canker in citrus groves; however, only Florida sources can be used for that purpose. Local sources of Casuarina are generally adequate seed producers, but germination percentages are frequently poor. Thus, the causes of low seed germination and methods to improve germination were investigated using C. cunninghamiana and a local hybrid (C. equisetifolia L. × C. glauca Sieb. ex Spreng.). Seeds of the hybrid were larger and heavier (88 mg/100 seeds) than those of C. cunninghamiana (mean wt. 67 mg/100 seeds). Shrunken, insect-damaged, and empty seeds, present in all unsorted seed lots, were responsible for poor seed germination of the four seed sources studied. Petroleum ether separation improved germination by dividing seeds into floaters and sinkers. The floater fraction consisted of 47.5% to 93% insect-damaged seeds compared with 9.0% to 43.5% among sinkers. More than 50% of the sinkers were filled seeds and less than 21% in floaters. No empty seeds were sinkers except for one source of C. cunninghamiana. In sorted hybrid seeds, petroleum ether separation eliminated a large proportion of ungerminable seeds (floaters) and seed germination among sinkers was faster with a higher germination percentage than floaters. Cumulative germination of hybrid seeds in a trial involving two temperatures was 23.0% for sunken seeds at 30 °C at the end of 8 weeks compared with 1% of unsorted seeds. Temperature had no significant effect on seed germination. The germination percentage of hybrid seeds with seedcoats removed was 91.0% in the first week of culture compared with only 1.2% in the first week and 12.6% seed germination at the end of 8 weeks' culture of intact seeds.

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The Effect of Sodium Hypochlorite (NaOCl) and Heat Treatments on Seed Germination of Rice: An Approach to Restore Seed Viability

Journal of Experimental Agriculture International ◽

10.9734/jeai/2021/v43i530689 ◽

2021 ◽

pp. 49-53

Author(s):

Monoj Sutradhar ◽

Subhasis Samanta ◽

Brijesh Kumar Singh ◽

Md. Nasim Ali ◽

Nirmal Mandal

Keyword(s):

Seed Germination ◽

Seed Dormancy ◽

Sodium Hypochlorite ◽

Seed Viability ◽

Germination Percentage ◽

Heat Treated ◽

Mother Plants ◽

Breaking Seed Dormancy ◽

One Year

Dormancy in rice serves as a mechanism of survival by protecting the seed from germinating in the mother plants; however, it becomes a problem in germination during sowing in soil or under in vitro conditions. This study was conducted to determine the effect of heat treatment and sodium hypochlorite (NaOCl) treatment of seeds on dormancy alleviation. The seeds included both freshly harvested seeds and one-year-old stored seeds, which were tested for germination after different types of seed treatments. Both the treatments increased the germination percentage in seeds, however, it was lesser in the case of old seeds. The best results were obtained from 2% NaOCl treatment for 24 hrs in new seeds, i.e. 92.84±0.103 % germination percentage (GP). However, the higher GP in old seeds were obtained from 48 hrs of heat-treated seeds i.e. 82.9±0.509 % GP. The results of the experiment revealed that rice seeds start to lose viability within a year due to seed dormancy, but this can be reversed with proper measures. These methods of breaking seed dormancy can be considered effective to break seed dormancy and improve seed germination in rice.

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