A Modified Approach for Axenic Cultivation of Spores of Fern Adiantum capillus-veneris L. with High Germination Rate

AbstractAlthough seed dormancy of temperate legumes is well understood, less is known about it in species that grow in subalpine/alpine areas. This study investigated dormancy and germination of four Vicia species from the Tibetan Plateau. Fresh seeds of V. sativa were permeable to water, whereas those of V. angustifolia, V. amoena and V. unijuga had physical dormancy (PY). One year of dry storage increased the proportion of impermeable seeds in V. angustifolia, but showed no effect on seed coat permeability in V. amoena or V. unijuga. Seeds of all four species also had non-deep physiological dormancy (PD), which was especially apparent in the two annuals at a high germination temperature (20°C). After 1 year of storage, PD had been lost. The hydrotime model showed that fresh seeds obtained a significantly higher median water potential [Ψb(50)] than stored seeds, implying that PD prevents germination in winter for seeds dispersed without PY when water availability is limited. After 6 months on the soil surface in the field, a high proportion of permeable seeds remained ungerminated, further suggesting that PD plays a key role in preventing germination after dispersal. Addition of fluridone, an inhibitor of abscisic acid (ABA) biosynthesis, evened-out the differences in germination between fresh and stored seeds, which points to the key role of ABA biosynthesis in maintaining dormancy. Further, fresh seeds were more sensitive to exogenous ABA than stored seeds, indicating that storage decreased embryo sensitivity to ABA. On the other hand, the gibberellic acid GA3 increased germination rate, which implies that embryo sensitivity to GA is also involved in seed dormancy regulation. This study showed that PY, PD or their combination (PY+PD) plays a key role in timing germination after dispersal, and that different intensities of dormancy occur among these four Vicia species from the Tibetan Plateau.

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Germination efficiency of clinical Clostridium difficile spores and correlation with ribotype, disease severity and therapy failure

Journal of Medical Microbiology ◽

10.1099/jmm.0.056614-0 ◽

2013 ◽

Vol 62 (9) ◽

pp. 1405-1413 ◽

Cited By ~ 29

Author(s):

P. Moore ◽

L. Kyne ◽

A. Martin ◽

K. Solomon

Keyword(s):

Clostridium Difficile ◽

Spore Germination ◽

Germination Rate ◽

Sodium Taurocholate ◽

Response To Treatment ◽

First Line Therapy ◽

High Germination ◽

Forming Efficiency ◽

Spore Outgrowth ◽

Ribotype 078

Spore germination is an important part of the pathogenesis of Clostridium difficile infection (CDI). Spores are resistant to antibiotics, including those therapeutically administered for CDI and strains with a high germination rate are significantly more likely to be implicated in recurrent CDI. The role of germination efficiency in cases of refractory CDI where first-line therapy fails remains unclear. We investigated spore germination efficiencies of clinical C. difficile isolates by measuring drop in OD600 and colony forming efficiency. Ribotype 027 isolates exhibited significantly higher germination efficiencies in the presence of 0.1 % (w/v) sodium taurocholate (51.66±8.75 %; 95 % confidence interval (CI) 47.37–55.95 %) than ribotype 106 (41.91±8.35 %; 95 % CI 37.82–46 %) (P<0.05) and ribotype 078 (42.07±8.57 %, 95 % CI 37.22–46.92 %) (P<0.05). Spore outgrowth rates were comparable between the ribotype groups but the exponential phase occurred approximately 4 h later in the absence of sodium taurocholate. Spore germination efficiencies for isolates implicated in severe CDI were significantly higher (49.68±10.00 %, 95 % CI 47.06–52.30 %) than non-severe CDI (40.92±9.29 %, 95 % CI 37.48–44.36 %); P<0.01. Germination efficiencies were also significantly higher in recurrent CDI or when metronidazole therapy failed than when therapy was successful [(49.00±10.49 %, 95 % CI 46.25–51.75 %) versus (41.42±9.43 %, 95 % CI 37.93–44.91 %); P<0.01]. This study suggests an important link between C. difficile spore germination, CDI pathogenesis and response to treatment; however, further work is warranted before the complex interplay between germination dynamics and CDI outcome can be fully understood.

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Comment Rubus alceifolius, une espèce exotique envahissante, pourrait-elle progressivement coloniser la totalité d'une forêt tropicale humide ?

Canadian Journal of Botany ◽

10.1139/b04-169 ◽

2005 ◽

Vol 83 (2) ◽

pp. 219-226 ◽

Cited By ~ 3

Author(s):

Stéphane Baret ◽

Thomas Le Bourgeois ◽

Dominique Strasberg

Keyword(s):

Sexual Reproduction ◽

Germination Rate ◽

Biological Traits ◽

Running Water ◽

High Germination ◽

Before And After ◽

Soil Seedbank ◽

Seed Distribution ◽

Quantitative Results ◽

Forestry Services

Few quantitative studies confirm or refute actual theories on the capacity of exotic species to invade and colonize new environments. To evaluate these theories, we tested some biological traits of an invasive bramble (Rubus alceifolius Poiret), known for the importance of its sexual reproduction on lowlands, at La Réunion (Indian Ocean). We studied R. alceifolius seed distribution in one of the last tropical lowland rainforests of the island. Seed count was greater under R. alceifolius patches (> 10 000 seed/m2) than in understoreys not colonized by the bramble (approximately 3000 seed/m2). In R. alceifolius patches, localized within gaps, our results showed that seed-rain and seed-bank before and after the fruit period decreased significantly from the center to the edge of the gap. This pattern was certainly due to the variation in luminosity, which decreased from the center of the gap to the edge. We conclude that seed dispersal of this species within the forest is mainly via running water. A number of seeds (10%20%) were able to wait for a new opening in which to germinate. A small proportion of these seeds remained viable in the soil for many years. Monospecific R. alceifolius patches can be considered nurseries and are the main source for colonization of new areas within the forest. Our quantitative results confirm that copious sexual reproduction, a large soil seedbank, and a high germination rate are biological traits that greatly contribute to the invasiveness of this plant. They also provide important information for forestry services establishing adapted control plans.Key words: seedbank, dissemination, introduced plant, biological invasion, life history traits, viability.

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SEED STERILIZATION USING SILVER IONS ANDSILVER NANOPARTICES SYNTHESIZED BY GREEN CHEMISTRY METHODS

BIOTECHNOLOGY: STATE OF THE ART AND PERSPECTIVES ◽

10.37747/2312-640x-2020-18-343-344 ◽

2020 ◽

pp. 343-344

Author(s):

A. Popova ◽

V. Zaitsev

Keyword(s):

Silver Nanoparticles ◽

Green Chemistry ◽

Germination Rate ◽

Silver Ions ◽

Effective Surface ◽

Surface Sterilization ◽

High Germination

Most effective surface sterilization of barley seeds is treatment by 0,14% AgNO3, producing maximal sterilization level coupled with high germination rate. Treatments of the seeds by H2O2 or silver nanoparticles synthesized by green chemistry methods were inefficient.

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Short-term aerated hydration for the improvement of seed quality in Brassica oleracea L

Seed Science Research ◽

10.1017/s0960258500001094 ◽

1992 ◽

Vol 2 (1) ◽

pp. 41-49 ◽

Cited By ~ 25

Author(s):

J. M. Thornton ◽

A. A. Powell

Keyword(s):

Moisture Content ◽

Seed Quality ◽

Germination Rate ◽

Germination Percentage ◽

Short Term ◽

Brussels Sprouts ◽

High Germination ◽

Controlled Deterioration ◽

Improved Performance ◽

Aged Seeds

AbstractSeeds of the Brussels sprouts cultivar Asmer Aries and the cauliflower cultivar Hipop were subjected to ageing at 20% moisture content and 45°C for 24 or 30 h, respectively; all seeds retained high germination after ageing. Aerated hydration of unaged and aged seeds of both cultivars for 4–8 h at a range of temperatures (10–30°C), followed by drying, resulted in improved performance, except that germination percentage and rate of cauliflower were lower at 10°C. Thus, all treated seeds showed greater germination rate and seedling root length than the control, which may have resulted from the advancement of the process of germination. The deleterious effect of aerated hydration at 10°C on cauliflower could be explained by damage due to rapid imbibition; seeds that had imbibed slowly to close to full imbibition (41% moisture content) before aerated hydration showed no decrease in germination. The improvement of aged seeds after aerated hydration was also revealed by higher germination after the controlled-deterioration test, which indicated less deterioration in treated seeds. Furthermore, the optimum improvements for all seeds were observed at 25°C and were greater when the water was aerated than non-aerated. These observations indicate the activation of metabolic repair processes during aerated hydration, leading to a reversal of the deterioration sustained during ageing.

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Effects of GA3Pregerminative Treatment onGentiana luteaL. var.aurantiacaGermination and Seedlings Morphology

The Scientific World JOURNAL ◽

10.1155/2014/751279 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 4

Author(s):

Óscar González-López ◽

Pedro A. Casquero

Keyword(s):

Germination Rate ◽

Wild Populations ◽

High Demand ◽

Seedling Morphology ◽

Gentiana Lutea ◽

High Germination ◽

Starting Point ◽

Alpine Species ◽

First Time ◽

Gentianae Radix

Gentiana luteaL. is widely used in bitter beverages and in medicine;Gentianae Radixis the pharmaceutical name of the root ofG. lutea. These uses have generated a high demand. The wild populations ofGentiana luteavar.aurantiaca(M. Laínz) M. Laínz have been decimated; it is necessary to establish guidelines for its cultivation. Gentian as most alpine species has dormant seeds. Dormancy can be removed by cold and by means of a gibberellic acid (GA3) treatment. However, cold treatments produce low germination percentages and GA3treatments may produce off-type seedlings. So, the objective was to determine, for the first time, the presowing treatments that allow high germination rate and good seedling morphology. The best pregerminative doses of GA3to break seed dormancy were 100, 500, and 1000 ppm, while the best doses to optimize the seedling habit were 50 and 100 ppm. This study provides, for the first time, a 100 ppm GA3dose that led to a high germination rate and good seedling morphology, as the starting point for gentian regular cultivation.

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Addition of Forchlorfenuron to Spray Pollination Media Increases Fruit Set in ‘Hosui’ Japanese Pear

HortTechnology ◽

10.21273/horttech.26.2.185 ◽

2016 ◽

Vol 26 (2) ◽

pp. 185-190

Author(s):

Daisuke Sakamoto ◽

Shinnosuke Kusaba ◽

Yuri Nakamura

Keyword(s):

Fruit Set ◽

Germination Rate ◽

Pollen Grains ◽

Fruit Production ◽

Fruit Shape ◽

Japanese Pear ◽

Pyrus Pyrifolia ◽

High Germination ◽

Hand Pollination ◽

Acceptable Method

The effects on fruit set of adding forchlorfenuron (CPPU) to media in which pollen grains were suspended and used for spray pollination was investigated in ‘Hosui’ japanese pear (Pyrus pyrifolia). The percentages of fruit set after spray pollination were lower than those after hand pollination; however, media with 2 or 10 mg·L−1 CPPU used for spray pollination resulted in greater percentages of fruit set than media without CPPU. The media with CPPU also resulted in higher levels of pollen germination compared with the medium without CPPU; however, the number of seeds per fruit with CPPU treatment tended to be almost the same or less than for fruit without CPPU treatment. From these results, the higher levels of fruit set by CPPU might not be due to the high germination rate of the pollen grains but due to the induction of partial parthenocarpic properties. The medium with 10 mg·L−1 CPPU gave the highest levels of fruit set, but the fruit had abnormally thickened and enlarged calyxes, and the fruit shape tended to be deformed at ≈21 days after flowering. In addition, all of the harvested fruit were calyx-perpetual fruit in which the calyx remains until harvest time. Fruit treated with 2 mg·L−1 CPPU also yielded calyx-perpetual fruit with high frequency, but the fruit had normal calyxes and the fruit shape tended to be more normal. Thus, we conducted experiments focusing on the medium containing 2 mg·L−1 CPPU. Although the results were variable from year to year, more than 70% of hand-pollinated flowers set fruit during the 3-year study; this level of fruit production is sufficient for practical use. Thus, spray pollination using a medium with 2 mg·L−1 CPPU is an acceptable method for pollinating ‘Hosui’ japanese pear.

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Determination of Different Priming Applications on Vicia freyniana Bronm. Seeds Viability Parametres

Agricultural Science Digest - A Research Journal ◽

10.18805/ag.d-242 ◽

2020 ◽

Author(s):

O. Yüksel ◽

B.B. Kenanoğlu ◽

R.G. Öncü

Keyword(s):

Research Laboratory ◽

Germination Rate ◽

Natural Sciences ◽

Hot Water ◽

Hot Water Treatment ◽

The Third ◽

Impregnation Technique ◽

High Germination ◽

Different Doses

Background: Legumes are the second among all the families in terms of varieties and Vicia genus is the third genus within the Leguminosae family. The germination and emergence rates decrease due to some reasons such as non-homogeneous genetic structure of seed or effect of environmental factors on it. For this reason, some quality problems occur. Quality enhancing applications are performed for seeds to have the desired quality levels in seeds and eliminate the problems. The aim of the present study was to determine the viability of Vicia freyniana Bornm. seeds by different priming treatments. For this purpose, the effect of different chemicals in different doses and periods and at what rate the hot water treatment would affect testa dormancy were studied. Methods: This study was conducted in Uşak University Agriculture and Natural Sciences Faculty Research laboratory in 2019. An investigation was conducted to determine the effects of the priming treatments (Soaking and imbibation; 2, 4 and 6% doses of NaCl, CaCl2 and KNO3 salts and 75, 100 and 125 ppm doses of GA3) on seeds of Vicia freyniana Bornm. In the study, the germination rate (%), germination speed (day), germination index (day) and EC values (µS/cm g-1) of the V. freyniana seeds were determined. Result: The highest germination rates were obtained from 2% of CaCl2 and 75 ppm of GA3 treatments and the fastest germination was observed in KNO3 treatment. From the study, it is concluded that 2% dose of CaCl2 and 75 ppm dose of GA3 should be preferred in V. freyniana seeds and the impregnation technique should be preferred among priming methods due to its high germination performance.

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On testing for seed sample heterogeneity with the exact probability distribution of the germination count range

Seed Science Research ◽

10.1017/s0960258520000112 ◽

2020 ◽

Vol 30 (1) ◽

pp. 59-63

Author(s):

Anderson Rodrigo da Silva

Keyword(s):

Empirical Distribution ◽

Probability Model ◽

Germination Rate ◽

Exact Probability ◽

Exact Test ◽

High Germination ◽

Count Range ◽

Rate Effects ◽

Exact Probability Distribution ◽

Sample Heterogeneity

AbstractSeed lot heterogeneity is often evaluated through the range between germination percentages of four seed samples, considering normal and binomial approximations for calculating the tolerated range (S). In this paper, an exact test for the germination count range (R) is derived based on the hypergeometric and the binomial probability model for germination count. Through Monte Carlo simulations, the empirical distribution of R is built to evaluate the quantiles of the exact distributions. Moreover, a power analysis is performed by simulation. Sample size and germination rate effects are evaluated. In lots with a high germination rate, the proposed test based on the hypergeometric model is about 20% more powerful than the test based on the S-value. A table containing the critical values is presented and recommended to be used in off-range heterogeneity testing.

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Viability rice seeds with different levels of antioxidants

E3S Web of Conferences ◽

10.1051/e3sconf/202124701076 ◽

2021 ◽

Vol 247 ◽

pp. 01076

Author(s):

Yulia Goncharova ◽

Olesya Bragina ◽

Sergey Goncharov ◽

Evgeniy Kharitonov

Keyword(s):

Germination Rate ◽

Total Content ◽

Cellular Level ◽

First Year ◽

Red Rice ◽

Black Rice ◽

Rice Varieties ◽

High Germination ◽

Rice Seeds ◽

White Grain

Total content of anthocyanidin glucosides varies greatly among different black varieties (79.5–473.7 mg / 100 g) and red rice (7.9–34.4 mg / 100 g). Shown up to 20 times higher content of antioxidants in black rice varieties, compared with white grain, as well as their up to 45 times higher antioxidant activity compared with many other crop. In terms of antioxidant content, black rice is not inferior even to such well-known sources as blueberries and black currants, but much cheaper. The role of phenolic acids as substances increasing adaptability to various stresses is considered. The presence of anthocyanidin glucoside is also useful for the plants themselves at the cellular level, normalizing metabolic processes in response to various unfavorable abiotic influences, thereby increasing their adaptability to stress and the viability of seeds . The objectives of the study were to identify germination rate of rice seeds various groups of ripeness, color of pericarp, shape and weight of caryopsis. Seeds of varieties stored in uncontrolled temperature conditions three years. Every year, a study germination of seeds all groups was carried out. 100 grains of each variety were placed in Petri dishes in three repetitions and germinated in a thermostat at a temperature of 29° C for 7 days, after which the percentage of germinated seeds was calculated. Our research showed a high germination rate seeds of red and black varieties. Them viability significantly exceeded white-grain varieties various groups of ripeness, weight and shape of caryopsis on second and third years of storage. If during the first year the differences in germination between most varieties are not reliable, then in the third year the white-grain varieties significantly inferior in vitality varieties of other groups.

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