Seed priming improves the germination and growth rate of melon seedlings under saline stress

ABSTRACT: The germination and growth of melon (Cucumis melo L.) plants can be severely affected by excess salts in the soil or irrigation water; however, negative effects of salt stress can be attenuated using appropriate methods of seed priming. Thus, effects of osmopriming as inducer of salt stress tolerance in melon seeds exposed to salinity levels were investigated in this study. Seeds were soaked for 22 h at 25 °C in the dark in distilled water (hydropriming) or 0.5% KNO3 solution (osmopriming), and after drying, were distributed in plastic boxes with blotter paper containing different NaCl solutions prepared with osmotic pressure of 0.0 MPa (control), -0.3 MPa (mild stress), and -0.6 MPa (severe stress). Unprimed dry seeds were taken as control. The plastic boxes were kept into a seed germinator, at 25 °C for 14 days. A completely randomized design in a 3 × 3 factorial schemes with four replicates of 25 seeds was used. Results showed that the seed priming with water and KNO3 may be successfully applied on melon seeds to alleviate the adverse effects of saline stress in initial stages of plant growth. However, under severe salt stress conditions, hydropriming should be used because it results in higher germination and initial growth rate of the seedlings when compared to the osmopriming. Use of unprimed seeds should not be adopted in cultivation areas affected by salinity because they result in low germination rate and reduced initial plant growth.

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Inducing salt tolerance in sweet corn by magnetic priming

Acta agriculturae Slovenica ◽

10.14720/aas.2017.109.1.09 ◽

2017 ◽

Vol 109 (1) ◽

pp. 89 ◽

Cited By ~ 13

Author(s):

Soheil Karimi ◽

Saeid ESHGHI ◽

Saeid KARIMI ◽

Saman HASAN-NEZHADIAN

Keyword(s):

Salt Stress ◽

Seed Germination ◽

Plant Growth ◽

Sweet Corn ◽

Germination Rate ◽

Nacl Stress ◽

Proline Accumulation ◽

Membrane Thermostability ◽

Germination And Growth ◽

Magnetic Priming

This study evaluates seed germination and growth of sweet corn under NaCl stress (0, 50, and 100 mM), after exposing the seeds to weak (15 mT) or strong (150 mT) magnetic fields (MF) for different durations (0, 6, 12, and 24 hours). Salinity reduced seed germination and plant growth. MF treatments enhanced rate and percentage of germination and improved plant growth, regardless of salinity. Higher germination rate was obtained by the stronger MF, however, the seedling were more vigorous after priming with 15 mT MF. Proline accumulation was observed in parallel with the loss of plant water content under 100 mM NaCl stress. MF prevented proline accumulation by improving water absorption. Positive correlation between H2O2 accumulation and membrane thermostability (MTI) was found after MF treatments, which revealed that MF primed the plant for salinity by H2O2 signaling. However, over-accumulation of H2O2 after prolonged MF exposure adversely affected MTI under severe salt stress. In conclusion, magnetic priming for 6 hours was suggested for enhancing germination and growth of sweet corn under salt stress.

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The efficacy of different seed priming agents for promoting sorghum germination under salt stress

PLoS ONE ◽

10.1371/journal.pone.0245505 ◽

2021 ◽

Vol 16 (1) ◽

pp. e0245505

Author(s):

Xiaofei Chen ◽

Ruidong Zhang ◽

Yifan Xing ◽

Bing Jiang ◽

Bang Li ◽

...

Keyword(s):

Salt Stress ◽

Seed Germination ◽

Germination Rate ◽

Principal Component ◽

Dry Weight ◽

Seed Priming ◽

Nacl Stress ◽

Future Research ◽

Fresh Weight ◽

Positive Effects

Sorghum [Sorghum bicolor (L.) Moench] seed germination is sensitive to salinity, and seed priming is an effective method for alleviating the negative effects of salt stress on seed germination. However, few studies have compared the effects of different priming agents on sorghum germination under salt stress. In this study, we quantified the effects of priming with distilled water (HP), sodium chloride (NaCl), potassium chloride (KCl), calcium chloride (CaCl2), and polyethylene glycol (PEG) on sorghum seed germination under 150 mM NaCl stress. The germination potential, germination rate, germination index, vigor index, root length, shoot length, root fresh weight, shoot fresh weight, root dry weight, and shoot dry weight were significantly reduced by salt stress. Different priming treatments alleviated the germination inhibition caused by salt stress to varying degrees, and 50 mM CaCl2 was the most effective treatment. In addition, the mitigation effect of priming was stronger on root traits than on shoot traits. Mitigation efficacy was closely related to both the type of agent and the concentration of the solution. Principal component analysis showed that all concentrations of CaCl2 had higher scores and were clearly distinguished from other treatments based on their positive effects on all germination traits. The effects of the other agents varied with concentration. The priming treatments were divided into three categories based on their priming efficacy, and the 50, 100, and 150 mM CaCl2 treatments were placed in the first category. The 150 mM KCl, 10% PEG, HP, 150 mM NaCl, 30% PEG, and 50 mM KCl treatments were placed in the second category, and the 100 mM NaCl, 100 mM KCl, 20% PEG, and 50 mM NaCl treatments were least effective and were placed in the third category. Choosing appropriate priming agents and methods for future research and applications can ensure that crop seeds germinate healthily under saline conditions.

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Alleviation of salt stress using gibberellic acid in Chinese cabbage

Acta Agronomica Hungarica ◽

10.1556/aagr.60.2012.4.5 ◽

2012 ◽

Vol 60 (4) ◽

pp. 345-355 ◽

Cited By ~ 2

Author(s):

M. Jamil ◽

M. Ashraf ◽

E. Rha

Keyword(s):

Salt Stress ◽

Gibberellic Acid ◽

Chinese Cabbage ◽

Germination Rate ◽

Harmful Effect ◽

Seed Priming ◽

Nacl Stress ◽

Growth And Yield ◽

Distilled Water ◽

Membrane Injury

Salinity reduces plant growth and yield by affecting morphological and physiological processes. To alleviate the harmful effects of salt stress various approaches involving plant hormones are used. In this study several parameters involving the measurement of cell membrane injury were used to observe whether stress tolerance could be enhanced in Chinese cabbage (B. oleracea capitata L. Chinensis group) by soaking the seeds for 10 h in distilled water (control), or in 100, 150 or 200 mg l−1 gibberellic acid (GA3). The NaCl concentrations were 0 (control), 50, 100 and 150 mM. Seed treated with GA3 showed increased water uptake and decreased electrolyte leakage as compared to that of distilled water-primed seeds even 24 h after soaking under control conditions. Seed priming with GA3 increased the final germination and the germination rate (1/t50, where t50 is the time to 50% germination) under salt stress conditions. Seed priming also alleviated the harmful effect of salt stress on cabbage in terms of fresh and dry weights. Leaf area was higher in plants raised from seeds primed with the higher GA3 concentrations as compared with those raised from seeds treated with distilled water under control conditions (without NaCl) or at 50 mM NaCl stress. The chlorophyll content increased with the NaCl concentration, especially in plants grown from seeds primed with GA3. Plants grown from GA3-primed seeds also suffered lower cellular injury both under control conditions and under NaCl stress.

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Amelioration of Saline Stress on Chia (Salvia hispanica L.) Seedlings Inoculated With Halotolerant Plant Growth-Promoting Bacteria Isolated From Hypersaline Environments

Frontiers in Agronomy ◽

10.3389/fagro.2021.665798 ◽

2021 ◽

Vol 3 ◽

Author(s):

María Florencia Yañez-Yazlle ◽

Neli Romano-Armada ◽

Verónica Beatriz Rajal ◽

Verónica Patricia Irazusta

Keyword(s):

Plant Growth ◽

Culture Media ◽

Saline Stress ◽

Plant Growth Promoting Bacteria ◽

Initial Growth ◽

Hypersaline Environments ◽

Salvia Hispanica ◽

Plant Growth Promoting ◽

Pgp Activities ◽

Growth Promoting

The rhizosphere and microbiome of halotolerant plants could be crucial for alleviating salinity stress during plant growth. The aims of this work were (1) to isolate bacteria from rhizosphere and bulk soil samples from the Salar del Hombre Muerto (Catamarca, Argentina), (2) to characterize different plant growth-promoting (PGP) activities produced by these bacterial isolates, and (3) to evaluate their effect on the initial growth of chia (Salvia hispanica L.) under saline stress. A total of 667 microorganisms were isolated, using different culture media with NaCl, and their abilities for nitrogen fixation, phosphate solubilization, siderophores production, and indole-3-acetic acid production were evaluated. Thirteen strains were selected for showing all the tested PGP activities; they belonged to the genera Kushneria, Halomonass, Pseudomonas, Planomicrobium, and Pseudarthrobacter. The strains Kushneria sp. and Halomonas sp. showed the highest salinity tolerance (from 50 to 2,000 mM NaCl) and biomass and biofilm production. Chia seeds were treated with six of the first 13 selected strains to evaluate their plant growth-promoting effect under saline stress (without and with 50 and 100 mM NaCl). Halomonas sp. 3R.12 and Kushneria sp. T3.7 produced heavier seedlings with a balanced shoot/root length ratio, while Pseudomonas sp. AN23 showed the best effect upon chia seedlings, with a morphological response similar to non-stressed seedlings. On the other hand, seedlings displayed no responses when inoculated with Planomicrobium sp. 3S.31 and Pseudarthrobacter sp. ER25. This study contributes to the knowledge on microorganisms from hypersaline environments as plant growth promoters for their use in the production of salt-sensitive crops, among other potential uses.

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Potasssium chloride as a nutrient seed primer to enhance salt‑tolerance in maize

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2012000800020 ◽

2012 ◽

Vol 47 (8) ◽

pp. 1181-1184 ◽

Cited By ~ 4

Author(s):

Badar‑uz‑Zaman ◽

Arshad Ali ◽

Syed Ishtiaq Hyder ◽

Muhammad Arshadullah ◽

Saqib Umar Bhatti

Keyword(s):

Salt Stress ◽

Salinity Stress ◽

Dry Matter ◽

Germination Rate ◽

Seed Priming ◽

Germination Percentage ◽

Stress Conditions ◽

Maize Crop ◽

Mean Germination Time ◽

Muriate Of Potash

The objective of this work was to determine if KCl could be a useful nutrient primer for safe seed germination in maize crop under salt stress conditions. Seed priming was done using 50 mmol L‑1 of muriate of potash, and germination and seedling growth were evaluated after salt stress with NaCl up to 50 mmol L‑1. Another set of seeds was tested under the same salt stress conditions without priming. Under salinity stress, germination percentage, germination rate index, germination coefficient, and seedling vigor indexes were higher in primed seeds. In unprimed seeds, mean germination time increased, while the germination rate index and the fresh and dry matter mass decreased more sharply with salinity stress. The Na/K ratio was higher in unprimed seeds.

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Influence of microbial priming and seeding depth on germination and growth of native wildflowers

Ecological Processes ◽

10.1186/s13717-021-00287-4 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Daniela Barrera ◽

Juan Luera ◽

Kaitlynn Lavallee ◽

Pushpa Soti

Keyword(s):

Seed Germination ◽

Plant Growth ◽

Plant Species ◽

Biomass Allocation ◽

Habitat Restoration ◽

Soil Microbes ◽

Germination Rate ◽

Native Soil ◽

The Impact ◽

Germination And Growth

Abstract Background Using native wildflowers for restoring marginal lands has gained considerable popularity. Establishment of wildflowers can be challenging due to several environmental factors. Restoring the microbial community in degraded habitats can potentially result in the native plant performance and habitat restoration. This study was conducted to investigate the impact of native soil microbes and seeding depth on germination of south Texas native wildflowers. Two wildflower species, Ratibida columnifera (Nutt.) (Mexican Hat) and Verbesina encelioides (Cav.) (cowpen daisy), were treated with microbial wash extracted from native soils, and germination rate was recorded for 14-day period. We further analyzed the growth, biomass allocation, and root colonization by mycorrhizal fungi in these two plants growing them in a plant growth chamber for 6 weeks. To determine the impact of seeding depth, we planted the seeds of the two plant species at 2-cm, 6-cm, and 12-cm depth and monitored germination and plant growth. Results The two species responded differently to the seeding depth and microbial wash treatments. Microbial wash treatment resulted in higher germination rate in R. columnifera compared to control, while it did not have any impact on V. encelioides seed germination. While microbial treatment did not influence the total biomass, it had a significant impact on the biomass allocation in both the plant species. R. columnifera seeds germinated at both 2-cm and 6-cm depth and did not germinate at 12 cm, while the V. encelioides seeds germinated only at 2 cm and did not germinate at 6-cm or 12-cm seeding depth. Conclusions While our results are species specific, our results indicate that native soil microbes can potentially improve the seed germination and growth of wildflowers. Our results also indicate the importance of specific seeding depth when sowing wildflower seeds for habitat restoration.

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Overview of the Role of Rhizobacteria in Plant Salt Stress Tolerance

Agronomy ◽

10.3390/agronomy11091759 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1759

Author(s):

Miguel Ayuso-Calles ◽

José David Flores-Félix ◽

Raúl Rivas

Keyword(s):

Salt Stress ◽

Plant Growth ◽

Osmotic Stress ◽

Nutrient Deficiency ◽

Cost Effective ◽

Growth And Yield ◽

Soil Conditions ◽

Saline Stress ◽

Plant Growth Promoting Bacteria ◽

Plant Tolerance

Salinity is one of the main causes of abiotic stress in plants, resulting in negative effects on crop growth and yield, especially in arid and semi-arid regions. The effects of salinity on plant growth mainly generate osmotic stress, ion toxicity, nutrient deficiency, and oxidative stress. Traditional approaches for the development of salt-tolerant crops are expensive and time-consuming, as well as not always being easy to implement. Thus, the use of plant growth-promoting bacteria (PGPB) has been reported as a sustainable and cost-effective alternative to enhance plant tolerance to salt stress. In this sense, this review aims to understand the mechanisms by which PGPB help plants to alleviate saline stress, including: (i) changes in the plant hormonal balance; (ii) release of extracellular compounds acting as chemical signals for the plant or enhancing soil conditions for plant development; (iii) regulation of the internal ionic content of the plant; or iv) aiding in the synthesis of osmoprotectant compounds (which reduce osmotic stress). The potential provided by PGPB is therefore an invaluable resource for improving plant tolerance to salinity, thereby facilitating an increase in global food production and unravelling prospects for sustainable agricultural productivity.

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Seed priming effects on germination and first growth of the medicinal plant Achillea millefolium L.

Journal of Phytology ◽

10.25081/jp.2020.v12.6324 ◽

2020 ◽

pp. 20-23

Author(s):

Panagiotis Kanatas ◽

Vyronas Dellaportas ◽

Ioanna Kakabouki ◽

Panayiota Papastylianou

Keyword(s):

Control Experiment ◽

Germination Rate ◽

Seedling Emergence ◽

Seed Priming ◽

Potassium Nitrate ◽

Potential Effect ◽

Germination Percentage ◽

Priming Effects ◽

Positive Effects ◽

Germination And Growth

This study evaluated the effects of seed priming on germination and growth of A. millefolium by means of laboratory and greenhouse experiments conducted during 2018 in the Agricultural University of Athens. Treatments were GA3 (400 and 800 ppm), potassium nitrate (2% and 4%), polyethylene-glycol (soaking for 12 and 24h) besides an untreated control. Experiment in Petri dishes revealed that GA3 at 400 ppm, potassium nitrate (at concentration 2 and 4%) and PEG significantly increased germination percentage of A. millefolium, while germination rate was also significantly improved as a result of all seed priming techniques. In addition, due to the soil experiment, seedling emergence was significantly increased by GA3 at 400 ppm, potassium nitrate (at both concentrations) and PEG compared with the untreated seeds. Dry biomass of the young seedlings was significantly enhanced by means of GA3 (at 400 and 800 ppm), KNO3 (4%) and PEG for 24 h, indicating the potential effect of seed priming on first growth as well. The results of the present study revealed the significant positive effects of seed priming on A. millefolium seed germination, seedling emergence and early growth.

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Effects of Hydro and Hormonal Seed Priming on Seed Germination of Milk Thistle under Saline Stress Condition

Notulae Scientia Biologicae ◽

10.15835/nsb639372 ◽

2014 ◽

Vol 6 (3) ◽

pp. 374-380

Author(s):

Yousef NASIRI ◽

Parisa FEYZI ◽

Abdollah JAVANMARD

Keyword(s):

Salicylic Acid ◽

Germination Rate ◽

Seed Priming ◽

Germination Percentage ◽

Milk Thistle ◽

Saline Stress ◽

Nacl Salinity ◽

Germination Time ◽

Randomized Design ◽

Mean Germination Time

Salinity is an abiotic stress which has harmful effects on germination of many plants. Therefore, high germination rate and vigorous early growth under salty soils is preferred. Seed priming is a way to increase salt tolerance of plants. An experiment was conducted to investigate the effect of seed priming on germination of milk thistle under salinity condition. The treatments were 4 levels of seed priming (no priming, distilled water as hydro priming and 0.5 and 1.0 mM salicylic acid) and 5 levels of salinity (0, 40 and 80 mM NaCl and 40 and 80 mM CaCl2). The experiment arranged as a factorial in a completely randomized design (CRD) with three replications. Results showed that salinity decreased germination percentage and germination rate to about 16 and 32% in 80 mM CaCl2 level compared to control, respectively. The highest mean germination time (5.7 day) were belonged to 80 mM CaCl2. Radicle and plumule length significantly decreased by 80 mM NaCl and 40 and 80 mM CaCl2. The lowest seedling weight and seed stamina observed in 80 mM CaCl2. 0.5 mM salicylic acid improved all traits except mean germination time as compared to control. Salicylic acid (0.5 mM) improved radicle length under 0, 40 and 80 mM NaCl salinity levels as well as increased plumule length at the 0 and 40 mM NaCl salinity conditions.

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Physiological quality of barley seeds submitted to saline stress

Revista Brasileira de Sementes ◽

10.1590/s0101-31222007000100006 ◽

2007 ◽

Vol 29 (1) ◽

pp. 40-44 ◽

Cited By ~ 7

Author(s):

Rodrigo Nascimento da Silva ◽

Nei Fernandes Lopes ◽

Dario Munt de Moraes ◽

Ana Lúcia de Almeida Pereira ◽

Gisela Loureiro Duarte

Keyword(s):

Salt Stress ◽

Germination Rate ◽

Membrane Integrity ◽

Seed Viability ◽

Saline Stress ◽

Barley Cultivars ◽

Physiological Quality

The objective of the experiments was to determine the influence of the effects of different salt levels (zero, 15, 30, 45 and 60mM NaCl) on the physiological quality of seeds of two barley cultivars (BRS 195 and AF 98067). Assays were conducted to evaluate salt stress on germination and vigor. The germination and germination rate of the barley seeds decreased as salt levels increased, reducing the seed viability and vigor. The salinity affected the membrane integrity, mainly in AF 98067 that showed more sensitivity to salt stress.

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