Effect of salt and water stresses on growth, nitrogen and phosphorus metabolism in Cucumis sativus L. seedlings

Plants exposed to osmotic stress exhibit changes in their physiology and metabolism. In general, osmotic stress reduces water availability and causes nutritional imbalance in plants. In the present study, we compared the response of cucumber (<em>Cucumis sativus</em> L. var. Władko F-1) to ionic (100 mmol•dm-3 NaCl) and osmotic stress (10% PEG 6000). Both stress factors reduced significantly fresh and dry weight of 7-day-old cucumber seedlings. Under PEG treatment reduction of cucumber dry mass was lesser than in fresh mass, whereas under salt stress decrease in dry weight of cucumber shoots was more pronounced than in fresh mass. Salt stress caused severe decrease in nitrate concentration and activity of nitrate reductase (NR). In cotyledons nitrate content declined to 17% of the control and similar reduction in NR activity was observed. In the roots, observed changes were not so drastic but there was also strong interaction between reduction in nitrate content and NR activity. Under 10% PEG both nitrate concentration and NR activity in cucumber roots were significantly higher in comparison to control plants. In cotyledons NR activity was significantly lower than in control plants, while decrease in nitrate content was not statistically significant. Phosphate concentration did not change significantly in cucumber cotyledons but increased in roots treated both NaCl (32% increase) and PEG (53% increase). Similar tendencies were observed in acid phosphatase activity. Obtained results indicated that osmotic and salt stresses evoke differential responses, particularly in growth reduction and nitrogen metabolism in cucumber seedlings.

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Halotolerant Microbial Consortia for Sustainable Mitigation of Salinity Stress, Growth Promotion, and Mineral Uptake in Tomato Plants and Soil Nutrient Enrichment

Sustainability ◽

10.3390/su13158369 ◽

2021 ◽

Vol 13 (15) ◽

pp. 8369

Author(s):

Chintan Kapadia ◽

R. Z. Sayyed ◽

Hesham Ali El Enshasy ◽

Harihar Vaidya ◽

Deepshika Sharma ◽

...

Keyword(s):

Salt Stress ◽

Salinity Stress ◽

Dry Weight ◽

Stress Factors ◽

Microbial Consortia ◽

Soil Conditions ◽

Mineral Uptake ◽

Shoot Height ◽

Tomato Plants ◽

Secondary Roots

Salinity significantly impacts the growth, development, and reproductive biology of various crops such as vegetables. The cultivable area is reduced due to the accumulation of salts and chemicals currently in use and is not amenable to a large extent to avoid such abiotic stress factors. The addition of microbes enriches the soil without any adverse effects. The effects of microbial consortia comprising Bacillus sp., Delftia sp., Enterobacter sp., Achromobacter sp., was evaluated on the growth and mineral uptake in tomatoes (Solanum Lycopersicum L.) under salt stress and normal soil conditions. Salinity treatments comprising Ec 0, 2, 5, and 8 dS/m were established by mixing soil with seawater until the desired Ec was achieved. The seedlings were transplanted in the pots of the respective pH and were inoculated with microbial consortia. After sufficient growth, these seedlings were transplanted in soil seedling trays. The measurement of soil minerals such as Na, K, Ca, Mg, Cu, Mn, and pH and the Ec were evaluated and compared with the control 0 days, 15 days, and 35 days after inoculation. The results were found to be non-significant for the soil parameters. In the uninoculated seedlings’ (control) seedling trays, salt treatment significantly affected leaf, shoot, root dry weight, shoot height, number of secondary roots, chlorophyll, and mineral contents. While bacterized seedlings sown under saline soil significantly increased leaf (105.17%), shoot (105.62%), root (109.06%) dry weight, leaf number (75.68%), shoot length (92.95%), root length (146.14%), secondary roots (91.23%), and chlorophyll content (−61.49%) as compared to the control (without consortia). The Na and K intake were higher even in the presence of the microbes, but the beneficial effect of the microbe helps plants sustain in the saline environment. The inoculation of microbial consortia produced more secondary roots, which accumulate more minerals and transport substances to the different parts of the plant; thus, it produced higher biomass and growth. Results of the present study revealed that the treatment with microbial consortia could alleviate the deleterious effects of salinity stress and improve the growth of tomato plants under salinity stress. Microbial consortia appear to be the best alternative and cost-effective and sustainable approach for managing soil salinity and improving plant growth under salt stress conditions.

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Effect of Naptalam on Chloramben Toxicity, Uptake, Translocation, and Metabolism in Cucumber (Cucumis sativus)

Weed Science ◽

10.1017/s0043174500057817 ◽

1991 ◽

Vol 39 (1) ◽

pp. 27-32

Author(s):

Larry D. Knerr ◽

Herbert J. Hopen ◽

Nelson E. Balke

Keyword(s):

Root Growth ◽

Cucumis Sativus ◽

Shoot Growth ◽

Petri Dish ◽

Dry Weight ◽

Laboratory Studies ◽

Cucumber Seedlings ◽

Plant Parts ◽

Cucumber Roots ◽

Hydroponically Grown

Laboratory studies demonstrated that naptalam safens cucumber against the phytotoxic effects of chloramben. In petri dish studies, cucumber seedlings grown from seeds exposed to chloramben plus naptalam had greater shoot growth, root growth, and dry weight than seedlings grown from seeds exposed to chloramben alone. Naptalam also partially reversed the reduction in dry weight of various plant parts caused by exposure of roots of hydroponically grown seedlings to chloramben. More radioactivity from root-applied14C-chloramben remained in cucumber roots and less was translocated to shoots with a14C-chloramben plus naptalam treatment than with a14C-chloramben alone treatment. Naptalam appeared to influence chloramben metabolism. In various plant parts, concentrations of chloramben and its metabolites differed between the two treatments.

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Biocontrol of Purple Nutsedge byBactra verutanaZeller in a Greenhouse

Weed Science ◽

10.1017/s0043174500032823 ◽

1977 ◽

Vol 25 (1) ◽

pp. 13-17 ◽

Cited By ~ 9

Author(s):

K.E. Frick ◽

P.C. Quimby

Keyword(s):

Osmotic Stress ◽

Cucumis Sativus ◽

Allium Cepa ◽

Nitrogen Deficiency ◽

Dry Weight ◽

Stress Conditions ◽

Cyperus Rotundus ◽

Plant Weight ◽

Purple Nutsedge ◽

Degree Of Control

The degree of control of purple nutsedge (Cyperus rotundusL.) provided byBactra verutanaZeller, a native moth, was evaluated for various stress conditions. Two, three, or four weekly infestations each with three larvae per live shoot, reduced purple nutsedge dry weight an average 77% compared with an average 55% for one infestation. Eight weekly infestations reduced plant dry weight 98%. Neither caging of the larvae on the plants nor osmotic stress with NaCl to −8 bars influenced larval efficacy, but nitrogen deficiency did reduce the effect of the larvae about 75%. Purple nutsedge had no effect on the dry weight of cucumber (Cucumis sativusL., ‘Straight Eight’) after 1 month, whether larvae were or were not present. Purple nutsedge did reduce the plant dry weight of okra (Abelmoschus esculentus(L.) Moench, ‘Clemson Spineless’) 64%, but repeated (eight) weekly infestations of larvae gave a plant weight of okra equal to that of okra grown without purple nutsedge. Purple nutsedge reduced the bulb and root dry weight of onion (Allium cepaL., ‘Big Valley’) 37%, but repeated weekly infestations of larvae gave onion growth equal to that of onion grown without purple nutsedge.

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Effect of External Nitrate Concentration on Nitrate and Iron Uptake and Assimilation in Vaccinium Species

HortScience ◽

10.21273/hortsci.40.4.1116c ◽

2005 ◽

Vol 40 (4) ◽

pp. 1116C-1116

Author(s):

Rebecca Darnell

Keyword(s):

Nitrate Reductase ◽

Iron Uptake ◽

Nitrate Uptake ◽

Nitrate Concentration ◽

Dry Weight ◽

Optimal Growth ◽

Low Ph ◽

Iron Nitrate ◽

Nr Activity ◽

Soil Adaptation

Most Vaccinium species, including V. corymbosum, have strict soil requirements for optimal growth, requiring low pH, high iron, and nitrogen, primarily in the ammonium form. V. arboreum is a wild species adapted to high pH, low iron, nitrate-containing soils. This broader soil adaptation in V. arboreum may be related to increased efficiency of iron or nitrate uptake/assimilation compared with cultivated Vaccinium species. To test this, nitrate and iron uptake, and nitrate reductase (NR) and ferric chelate reductase (FCR) activities were compared in two Vaccinium species, V. arboreum and the cultivated V. corymbosum. Plants were grown hydroponically for 15 weeks in either 1.0 or 5.0 mm NO3 with 0.09 mm Fe. Root FCR activity was greater in V. arboreum compared with V. corymbosum, especially at the lower external nitrate concentration. However, this was not reflected in differences in iron uptake. Nitrate uptake and root NR activity were greater in V. arboreum compared with V. corymbosum. The lower nitrate uptake and assimilation in V. corymbosum was reflected in decreased plant dry weight compared with V. arboreum. V. arboreum appears to be more efficient in acquiring nitrate compared with V. corymbosum, possibly due to increased NR activity, and this may partially explain the wider soil adaptation of V. arboreum.

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Allelopathic Effects of Alfalfa Plant Residues on Emergence and Growth of Cucumber Seedlings

HortScience ◽

10.21273/hortsci.26.4.368 ◽

1991 ◽

Vol 26 (4) ◽

pp. 368-370 ◽

Cited By ~ 10

Author(s):

James E. Ells ◽

Ann E. McSay

Keyword(s):

Particle Size ◽

Seed Germination ◽

Cucumis Sativus ◽

Dry Weight ◽

Plant Residues ◽

Alfalfa Plant ◽

Cucumber Seedlings ◽

Growing Medium ◽

Intermediate Size ◽

Allelopathic Effects

Growth chamber tests demonstrated that alfalfa (Medicago sativa L.) residue is toxic to cucumber (Cucumis sativus L.) seed germination and seedling growth. Ground alfalfa roots at 0.5% (w/w, dry weight) inhibited germination when added to the growing medium. Alfalfa roots at 0.5% were also toxic to pregerminated cucumber seed. However, cucumber seedlings grew normally if this same medium was watered and incubated for >1 day before planting. Alfalfa particle size in media influenced cucumber performance, with the intermediate size (1 to 2 mm) being lethal to cucumbers.

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Bazı Yerel Ekmeklik Buğday (Triticum aestivum L.) Genotiplerinin Erken Gelişme Dönemindeki Tuz Stresine Toleransının İncelenmesi

Turkish Journal of Agriculture - Food Science and Technology ◽

10.24925/turjaf.v8i3.688-693.3192 ◽

2020 ◽

Vol 8 (3) ◽

pp. 688

Author(s):

Kübra Özdemir Dirik ◽

İbrahim Saygılı ◽

Mahir Özkurt ◽

Mehmet Ali Sakin

Keyword(s):

Salt Stress ◽

Bread Wheat ◽

Growth Stage ◽

Dry Weight ◽

Germination Percentage ◽

Early Growth ◽

Stress Factors ◽

Coleoptile Length ◽

Early Growth Stage ◽

Wheat Genotypes

Salinity is one of the most important abiotic stress factors causing serious problems in agricultural areas in the world. In this study aimed to determine the salt stress tolerance of local bread wheat genotypes collected from some provinces of Turkey and provided from seed gene banks in our country in early growth stage. In the research, twenty five local bread wheat genotypes and four registered bread wheat cultivars as standard were used as material. Genotypes were subjected to salt stress germination percentage, radicle length, coleoptile length, shoot length, germination index, root fresh and dry weight, were measured. Germination percentage was decreased significantly by 39.1 % in salt application compared to the control. According to the germination percentages, TR 53869, Kate A1 and Pehlivan genotypes were found to be tolerant to salt stress in early growth stage TGB 000543 and TR 63579 were sensitive. Considering all traits investigated, genotype TR 53869 can be considered as a genotype tolerant to salt stress in early growth stage. It is predicted that this genotype can be used in breeding studies for the areas where salt stress is a problem in wheat.

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Response of Cucumis sativus L. seedlings to Pb exposure

Brazilian Journal of Plant Physiology ◽

10.1590/s1677-04202009000300002 ◽

2009 ◽

Vol 21 (3) ◽

pp. 175-186 ◽

Cited By ~ 6

Author(s):

Jamile F. Gonçalves ◽

Alexssandro G. Becker ◽

Luciane B. Pereira ◽

João B. T. da Rocha ◽

Denise Cargnelutti ◽

...

Keyword(s):

Cucumis Sativus ◽

Soluble Protein ◽

Chlorophyll Concentration ◽

Dry Weight ◽

Total Soluble Protein ◽

Cucumis Sativus L ◽

Cucumber Seedlings ◽

Pb Exposure ◽

Pb Concentration

In this study, the effects of lead (Pb) on growth, photosynthetic pigments concentration, lipid peroxidation, electrolyte leakage percentage (ELP), protein oxidation, aminolevulinate dehydratase (ALA-D; E.C. 4.2.1.24), ascorbate peroxidase (APX; E.C. 1.11.1.11), catalase (CAT; E.C. 1.11.1.6) and superoxide dismutase (SOD; E.C. 1.15.1.1) activities, and ascorbic acid (AsA), non-protein thiol groups (NPSH) and total soluble protein concentrations in cucumber seedlings (Cucumis sativus L.) were investigated. Seedlings were grown in vitro in an agar-solidified substrate containing three Pb levels as (C2H3O2)Pb.3H2O (0, 100, 400, and 1000 µmol L-1) for 10 d. Increasing Pb concentrations in substrate enhanced Pb concentration in both roots and shoot. Pb accumulated at a higher amount in roots. Root length and total fresh weight were decreased at the two highest Pb concentrations. Cucumber showed no reduction in shoot length and total dry weight at any Pb level. The highest Pb concentration decreased water content and ALA-D activity as well as increased malondialdehyde, carbonyls and total soluble protein concentrations. Carotenoids concentration enhanced at 100 and 400 µmol Pb L-1, while chlorophyll concentration and ELP were not affected by Pb stress. Activity of APX was inhibited while the activities of CAT and SOD were increased at all Pb concentrations. AsA was enhanced at 400 and 1000 µmol Pb L-1 whereas NPSH were increased only at the highest Pb concentration. Therefore, high Pb-exposure caused oxidative stress, and the antioxidant system of the cucumber seedlings was not sufficient to revert it, contributing for growth reduction.

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Altered Root Growth, Auxin Metabolism and Distribution in Arabidopsis thaliana Exposed to Salt and Osmotic Stress

International Journal of Molecular Sciences ◽

10.3390/ijms22157993 ◽

2021 ◽

Vol 22 (15) ◽

pp. 7993

Author(s):

Ana Smolko ◽

Nataša Bauer ◽

Iva Pavlović ◽

Aleš Pěnčík ◽

Ondřej Novák ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Salt Stress ◽

Osmotic Stress ◽

Root Growth ◽

Plant Root ◽

Stress Factors ◽

Quiescent Center ◽

Gene Expressions ◽

Auxin Distribution ◽

Salt And Osmotic Stress

Salt and osmotic stress are the main abiotic stress factors affecting plant root growth and architecture. We investigated the effect of salt (100 mM NaCl) and osmotic (200 mM mannitol) stress on the auxin metabolome by UHPLC-MS/MS, auxin distribution by confocal microscopy, and transcript levels of selected genes by qRT-PCR in Arabidopsis thaliana ecotype Columbia-0 (Col-0) and DR5rev::GFP (DR5) line. During long-term stress (13 days), a stability of the auxin metabolome and a tendency to increase indole-3-acetic acid (IAA) were observed, especially during salt stress. Short-term stress (3 h) caused significant changes in the auxin metabolome, especially NaCl treatment resulted in a significant reduction of IAA. The data derived from auxin profiling were consistent with gene expressions showing the most striking changes in the transcripts of YUC, GH3, and UGT transcripts, suggesting disruption of auxin biosynthesis, but especially in the processes of amide and ester conjugation. These data were consistent with the auxin distribution observed in the DR5 line. Moreover, NaCl treatment caused a redistribution of auxin signals from the quiescent center and the inner layers of the root cap to the epidermal and cortical cells of the root elongation zone. The distribution of PIN proteins was also disrupted by salt stress; in particular, PIN2 was suppressed, even after 5 min of treatment. Based on our results, the DR5 line was more sensitive to the applied stresses than Col-0, although both lines showed similar trends in root morphology, as well as transcriptome and metabolome parameters under stress conditions.

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Effect of salinity and drought stress on germination and early seedlings growth of bread wheat (Triticum aestivum L.)

Genetika ◽

10.2298/gensr1801285j ◽

2018 ◽

Vol 50 (1) ◽

pp. 285-298 ◽

Cited By ~ 3

Author(s):

Mirjana Jovovic ◽

Vesna Tunguz ◽

Milan Mirosavljevic ◽

Novo Przulj

Keyword(s):

Salt Stress ◽

Osmotic Stress ◽

Winter Wheat ◽

Wheat Variety ◽

Dry Weight ◽

Triticum Aestivum L ◽

Genotypic Difference ◽

Water Deficit Stress ◽

Wheat Varieties ◽

Germination Energy

Salinity is one of the most important environmental stresses that limits soil fertility and has adverse effects on plant growth. In order to increase wheat production under saline conditions, it is necessary to better understand genotypic difference, the physiological and biochemical processes of salt tolerance in wheat. The aim of this study was to determine the most tolerant winter wheat varieties against salinity and osmotic stress at germination stage and early seedlings growth. The salinity and osmotic stress were simulated in controlled environmental conditions by adding different concentrations of NaCl and mannitol solution to the growing media of five winter wheat variety. In all studied varieties the benchmark water potential in which they had germinated and had a good seedlings growth was of -0.3MPa. Under the stronger stress, -0.6 MPa, all varieties showed reduction in the all examined parameters. The variety Bosanka, had the highest final germination and germination energy under both mannitol and salt stress treatments. The parameters defining the development or percentage of strong seeds, coleoptile and root length, fresh and dry weight of root and coleoptile of a seed were more affected by water deficit stress and salt stress than germination and germination energy. Biplot analysis showed that wheat cultivars grown under -0.6MPa osmotic had higher values of root/coleoptile ratio in relation to control and -0.3MPa treatment which is the most reliable for screening properties of the genotypes for drought resistance in seedling stage.

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Salinity Tolerance of Black Gram Cultivars During Germination and Early Seedling Growth

Cercetari Agronomice in Moldova ◽

10.2478/cerce-2018-0025 ◽

2018 ◽

Vol 51 (3) ◽

pp. 51-68 ◽

Cited By ~ 1

Author(s):

M.K. Hasan ◽

M.S. Islam ◽

M.R. Islam ◽

H.N. Ismaan ◽

A. El Sabagh

Keyword(s):

Salt Stress ◽

Salinity Tolerance ◽

Seedling Growth ◽

Negative Impact ◽

Germination Rate ◽

Dry Weight ◽

Germination Percentage ◽

Shoot Length ◽

Sand Culture ◽

Black Gram

Abstract A laboratory experiment regarding germination and seedling growth test was conducted with three black gram genotypes tested under three salinity levels (0, 75 and 150 mM), for 10 days, in sand culture within small plastic pot, to investigate the germination and seedling growth characteristics. Different germination traits of all black gram genotypes, like germination percentage (GP), germination rate (GR), coefficient of velocity of germination (CVG) greatly reduced, as well as mean germination time (MGT) increased with increasing salt stress. At high salt stress, BARI Mash-3 provided the highest GP reduction (28.58%), while the lowest was recorded (15.79% to control) in BARI Mash-1. Salinity have the negative impact on shoot and root lengths, fresh and dry weights. The highest (50.32% to control) and lowest reduction (36.39%) of shoot length were recorded in BARI Mash-2 and BARI Mash-1, respectively, under 150 mM NaCl saline conditions. There were significant reduction of root lengths, root fresh and dry weight, shoot length, shoot fresh and dry weight in all genotypes under saline condition. The genotypes were arranged as BARI Mash-1 > BARI Mash-3 > BARI Mash-2, with respect to salinity tolerance.

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