Plant Stress
Rabeb El khaldi; Dhaouadi Latifa; Besser Houda
Abstract
Purpose: In Oasis areas, salinity becomes a real threat for sustainable agricultural production, and with the introduction of non-native varieties, salinity pressure is more expressed and has harmful outcomes to the local ecosystem and biodiversity. In this context the present study was conducted ...
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Purpose: In Oasis areas, salinity becomes a real threat for sustainable agricultural production, and with the introduction of non-native varieties, salinity pressure is more expressed and has harmful outcomes to the local ecosystem and biodiversity. In this context the present study was conducted to compare salt stress behavior of local oasian and introduced cultivars. Research method: Seeds of two local oasian cultivars namely Djerid (Dj) and Nefta (Ne) and one exotic cultivar namely Cayenne (Ca) were treated with four salt concentrations (0; 2.5; 5 and 7g/l NaCl). Salt stress responses were evaluated using germination parameters and early seedling growth. Findings: Results revealed that the increase of salinity level had negatively effect on germination and early seedling for the three cultivars. However oasian cultivars were found to be the most tolerant to salinity. Ne cultivar showed the highest germination percentage and germination index and the lowest mean germination time at 7g/l NaCl concentration. Also, “Ne” performs better on seedling traits as indicated by the less effect of the high salinity on radicle and plumule length as well as plumule fresh weight, compared to the other cultivars. The introduced cultivar “Ca” was identified to be the most sensitive to salt stress. Limitations: No limitations were founded. Originality/Value: This study valorized the autochthone chili pepper cultivars by highlighting their salt stress tolerance. Thus, oasian genotypes could be very useful as genetic resources for the development of chili pepper cultivars with improved germination and seedling growth under salt-stress conditions.
Plant Stress
Mohammad Seirafinia; Arash Omidi; Aria Rasooli; Mehdi Mohebbi; Saeed Hoseinzadeh
Abstract
Purpose: Comparison and determination of ZEN production capacity of F. oxysporum, F. graminearum, and F. solani. The influence of low temperature stress and incubation time on the production of ZEN was also investigated. Research Method: Production of ZEN was evaluated by incubating media cultures at ...
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Purpose: Comparison and determination of ZEN production capacity of F. oxysporum, F. graminearum, and F. solani. The influence of low temperature stress and incubation time on the production of ZEN was also investigated. Research Method: Production of ZEN was evaluated by incubating media cultures at a constant temperature of 25°C for a period of 14 days before being incubated at 8°C for 14 days (Low-temperature stress/ LTS). The second set of the samples was incubated at constant 25°C for 4 weeks’ time (constant- temperature/ CT). HPLC and a fluorescence detector were employed to measure the concentration of ZEN. The species-specific pair of primers was used to perform a PCR assay on the fungal DNA. Findings: The higher levels of ZEN were seen at LTS compared with CT in three Fusarium species. The highest ZEN was produced in F. oxysporum media cultures. The significant production of ZEN was seen when F. oxysporum incubated at LTS compared with CT (P≤0.05). The highest and the lowest levels of ZEN were seen in F. oxysporum and F. solani and the difference of ZEN production by them were significant in CT and LTS, respectively (P≤0.05). ZEN production for the F. graminearum was in the intermediate level. Presence of PKS4 gene was confirmed by PCR in these Fusarium species. Limitations: Higher cost of ZEN detection by HPLC was a limitation. Originality/Value: Production of ZEN in LTS and CT by the Fusarium evaluated species was confirmed. However, LTS stimulate ZEN production in Fusarium media cultures, especially for F. oxysporum.
Plant Stress
Simeneh Tamrat Alemu; Habtamu Gebre
Abstract
Purpose: Ultraviolet-B radiation was inducing enormous stress at highland and coldest area since it increases more than 40% at highland when we compare with lowland. Therefore, this review aims to assess and depict impacts of Ultraviolet-B radiation on photosynthetic efficiency, growth performance, and ...
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Purpose: Ultraviolet-B radiation was inducing enormous stress at highland and coldest area since it increases more than 40% at highland when we compare with lowland. Therefore, this review aims to assess and depict impacts of Ultraviolet-B radiation on photosynthetic efficiency, growth performance, and yield of crops based on altitude. Findings: Indicate that ultraviolet-b radiation has a severe effect on photosynthesis, especially the coldest time. It reduces photosynthetic efficiency in such an area, but it depends on the type of the crop and cultivar difference. On the other hand, it reduces growth performance and biomass accumulation based on altitude. There is a contrasting view on a net-assimilation rate on different studies condition. The effect of UV-B on crop yield was more contrasting in some studies says no effect on other studies it says it affect, but this contradictory result was mainly due to the difference in study conditions, still current studies on Yield revealed that UV-B has a high impact on yield. Research limitations: Ultraviolet-B radiation has high effect on the highland area, but there is no much research focuses, but UV-B was profoundly affecting photosynthetic efficiency, growth performance and yield of crops on highland area. Directions for future research: UV-B was reducing crop production, and productivity at highland and this review gives more insights on UV-B impact at the highland and allow UV-B adaptive and preventive investigation in the future.
Plant Stress
Esmaeil Jadidi; Maryam Tatari; Mahmoud Ghasemnezhad; Hamid Reza Salemi
Abstract
Purpose: Identification of pomegranate cultivars with higher tolerance to salinity stress was the purpose of the current study. Research Method: One-year-old rooted cuttings of the pomegranate cultivars including 'Malase Saveh' ('M-Saveh'), 'Malase Isfahan' ('M-Isfahan'), 'Robabe Ghermeze Shiraz' ('Robab'), ...
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Purpose: Identification of pomegranate cultivars with higher tolerance to salinity stress was the purpose of the current study. Research Method: One-year-old rooted cuttings of the pomegranate cultivars including 'Malase Saveh' ('M-Saveh'), 'Malase Isfahan' ('M-Isfahan'), 'Robabe Ghermeze Shiraz' ('Robab'), 'Gabrie Yazd' ('G-Yazd'), Gabrie Torshe Yazd' ('GT-Yazd'), 'Zaghe Sefide Yazd' ('ZS-Yazd'), 'Zaghe Torshe Yazd' ('ZT-Yazd') and 'Malase Torshe Pishva' ('M-Pishva') were cultured in plastic pots and treated with different concentrations of sodium chloride in irrigation water including 0 (control), 3, 6, 9 and 12 dS m-1. Findings: At 12 dS m-1salinity level, the lowest decrease in plant height was observed in 'Robab', and 'M-Pishva' and the lowest decrease in the plant diameter was recorded in 'ZT-Yazd' and 'G-Yazd'. At the same salinity level, 'GT-Yazd' showed the lowest percentage of increase in electrolyte leakage (EL) compared to the control (23%). The highest increase in proline content was observed at 9 dS m-1 salinity for 'ZS-Yazd' and at 12 dS m-1 salinity for 'GT-Yazd'. At high salinity levels, leaf chlorophyll content decreased in pomegranate cultivars compared to the control. The activity of peroxidase enzyme in 'M- Pishva', ZT-Yazd' and 'GT-Yazd' followed an increasing and then decreasing with increasing salinity levels. The activity of the superoxide dismutase enzyme was highest in 'G-Yazd', 'M-Isfahan' and 'Robab'. Limitations: Investigation of salinity tolerance in pots is one of the limitations of this study. Originality/Value: Yazd cultivars including 'G-Yazd', 'GT-Yazd', 'ZS-Yazd' and 'ZT-Yazd' were more tolerant to salinity stress.
Plant Stress
Farhad Azarmi-Atajan; Mohammad Hassan Sayyari-Zohan
Abstract
Purpose: The effect of Pseudomonas sp. rhizobacteria as plant growth-promoting rhizobacteria (PGPR) in alleviating salt stress in the lettuce plant was studied under greenhouse condition. Research Method: The experiment was conducted following a completely randomized design with three replicates. The ...
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Purpose: The effect of Pseudomonas sp. rhizobacteria as plant growth-promoting rhizobacteria (PGPR) in alleviating salt stress in the lettuce plant was studied under greenhouse condition. Research Method: The experiment was conducted following a completely randomized design with three replicates. The treatments include four Pseudomonas sp. strains (B0 (non-inoculated), B1, B2 and B3) as PGPR and three levels of irrigation water salinity (0, 4 and 8 dS m-1 as NaCl). Findings: The results showed that with rising salinity levels the lettuce fresh and dry weight, chlorophyll and carotenoids content and K concentration decreased but, the content of membrane stability index (MSI), Na and Na/K ratio increased. However, inoculation of the lettuce plants by PGPR significantly increased the lettuce fresh and dry weight, chlorophyll and carotenoids content, K concentration and K/Na ratio under various salinity levels. Among the PGPR strain, the B2 strain was more effective in the improvement of the lettuce resistance to salinity stress. Research limitations: If antioxidant compounds and enzymes were measured in this study, it would be helpful to interpret the results. Originality/Value: with regards to the useful impact of the PGPR on the lettuce plant under soil salinity, these microorganisms can be used as biofertilizer to provide nutrients and increase plant resistance to salt stress.
Plant Stress
Seyyedeh Atefeh Hosseini; Mehdi Khayyat
Abstract
Purpose: The present research was done to evaluate the responses of ‘Yusef Khani’ (Y) and ‘Malas-e-Yazdi’ (M) Iranian pomegranates to salt stress under field conditions. Research method: Treatments included different salinized water (EC=1.05 as control, 4.61 and 7.46 dS m–1) ...
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Purpose: The present research was done to evaluate the responses of ‘Yusef Khani’ (Y) and ‘Malas-e-Yazdi’ (M) Iranian pomegranates to salt stress under field conditions. Research method: Treatments included different salinized water (EC=1.05 as control, 4.61 and 7.46 dS m–1) and two commercially Iranian pomegranate varieties. Main findings: Interaction of salinity × variety showed the lowest chlorophyll (chl) and potassium (K) level, and the highest chloride (Cl) and sodium (Na) in M variety, under high level of salinity. Although the lowest non-photochemical quenching, and effective quantum yield of photochemical energy conversion in PSII observed in this variety under 7.46 dS m–1, however, basal quantum yield of non-photochemical processes in PSII increased. Accumulation of Na and Cl in leaf tissue increased with increasing salinity in both varieties. Moreover, lower accumulation of calcium (Ca), magnesium (Mg) and iron (Fe) observed in both varieties. More Na and Cl was obtained within leaves of M variety, compared with other one. We found that there were some differences between these varieties and ‘Yousef Khani’ was more tolerant to salinity compared with ‘Malas-e-Yazdi’. Limitations: It might be better to evaluate several varieties for salinity resistance, however, it was impossible to us. Originality/Value: Iran is the main source of genetic variability for pomegranate. There is a huge diversity within pomegranate germplasm that should be studied for salinity and drought resistance. Thus, here we conducted a research to find a salt resistant pomegranate.
Plant Stress
Farid Moradinezhad; Soheyla Hajizadegan; Mohammad Hassan Sayyari; Mehdi Khayyat
Abstract
Purpose: Boron toxicity is an important factor, which reduces crop productivity, quality and medicinal characteristics around the world. Research method: This research was conducted to investigate the effect of different boron (B) concentrations on growth, chemical and physiological characteristics of ...
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Purpose: Boron toxicity is an important factor, which reduces crop productivity, quality and medicinal characteristics around the world. Research method: This research was conducted to investigate the effect of different boron (B) concentrations on growth, chemical and physiological characteristics of Satureja hortensis plants under greenhouse conditions in 2016. The experiment was conducted in a glasshouse with 25±3 °C and 15±3 °C (day-night) temperatures, 60% relative humidity and 340 ppm CO2 concentration. Treatments were different B concentrations as H3BO3 that used via irrigation water including 0, 5, 10, 25 and 50 mg L–1. Main findings: Results indicated that total nitrogen, Fm, Fv, Fv/Fm, chlorophyll a, b and total, leaf number, relative water content (RWC), specific leaf weight (SLW), areal fresh and dry weights significantly decreased by B increase. On the other hand, increased B concentration in leaf was led to increasing of F0, ΦN0, proline, total carbohydrate and phenolics, specific leaf area and leaf electrolyte leakage. Limitations: No significant limitation to report. Originality/Value: It is concluded that summer savory can tolerate B concentrations up to 10 mg L–1, and leaf boron accumulation significantly inhibited, however, increased with more B concentration of root medium, which affected all physiological aspects mentioned above.
Plant Stress
Fatemeh Sheikh Abol-hasani; Parto Roshandel
Abstract
Purpose: To evaluate the effects of NaCl priming to increase salt tolerance in Dracocephalum moldavica L. an experiment was conducted as factorial based on completely randomized design at Shahrekord University. Research method: Seeds of medicinal plant D. moldavica were primed with NaCl (1 M/ for 24 ...
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Purpose: To evaluate the effects of NaCl priming to increase salt tolerance in Dracocephalum moldavica L. an experiment was conducted as factorial based on completely randomized design at Shahrekord University. Research method: Seeds of medicinal plant D. moldavica were primed with NaCl (1 M/ for 24 h/ at darkness/ under 25˚C) and then 30-day-old plants were introduced to salinity (0, 100 and 150 mM NaCl) for one month. The analyzed parameters consisted of dry weight, leaf area, total water content, leaf relative water content, electrolyte leakage, lipid peroxidation, photosynthetic pigments concentrations, total phenolic content and the activity of antioxidant enzymes. Main findings: NaCl-priming alleviated the injurious effects of salinity in the salinized plants. The biomass increased up to 64.5% and 3-fold at 100 and 150 mM NaCl, compared to exclusively salinity. Ion leakage and lipid peroxidation decreased as well. Moreover, NaCl-priming led to increase leaf area, improve water status, photosynthetic pigments content and antioxidant enzymes activities in favor of improving the biomass of salinized D. moldavica. Total phenolic content increased by salinity alone, but NaCl-priming markedly decreased it at normal condition. The pattern of polyphenols concentration and accumulation was different under NaCl-priming + salinity treatment. Limitations: No special limitations were founded. Originality/Value: Seed priming with NaCl enhanced salt tolerance in D. moldavica through improving water status and photosynthesis, protection of cellular membrane integrity and changes in antioxidant enzyme activity. Alternation in polyphenols concentration might be a signature of changes in the medicinal properties of different parts of this medicinal plant.
Plant Stress
Simeneh Tamrat Alemu; Amsalu Gobena Roro
Abstract
Purpose: herbaceous dicot plants mainly sweet potato is highly affected by UV-B and light quality based on altitude. Therefore, this study will give insights on the effect of UV-B and light quality on photosynthetic efficiency of sweet potato based on Altitude. Research method: The experimental design ...
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Purpose: herbaceous dicot plants mainly sweet potato is highly affected by UV-B and light quality based on altitude. Therefore, this study will give insights on the effect of UV-B and light quality on photosynthetic efficiency of sweet potato based on Altitude. Research method: The experimental design was laid out in split plot design with factorial arrangement. The treatments consist of +UV-B or control, UV-B exclusion, UV-B+end of day light exclusion, and the two sweet potato cultivars such as Kulfo and Hawassa-83. Main findings: highest UV-B (1693.0mw/m-2s-2) was recorded at highland (2230m.a.s.l) and the lowest (1107mw/m-2s-2) was recorded at lowland (1400m.a.s.l). The result shows that photosynthetic rate increased by 2.41% in Kulfo compared with Hawassa83 cultivar. Also altitude has a highly significant effect on photosynthetic efficiency; the highest stress level 0.68 and 0.72 was recorded at UV-B + EOD exclusion and highland. This indicate UV-B +EOD exclusion cause light quality and intensity stress at highland also UV-B was inducing high stress at highland area and affecting sweet potato productivity but exclusion increase Fv/Fm and stomata conductance it has no effect on photosynthesis and transpiration rate. Limitations: The research has a limitation due to Altitude difference it’s difficult to control factors other than UV-B and light Quality that may cause a difference. Originality/Value: This research tries to assess UV-B and end of day time light quality effects due to altitude difference and encourages new research on UV-B, its adaptation and light quality on crop productivity.
Plant Stress
Puran Bridgemohan; Majeed Mohammed; Ronell S. H. Bridgemohan; Zareef Mohammed
Abstract
Purpose: Significant research on yield improvement of wetland rice provided a greater understanding of stress physiology, but less on ecophysiology of anaerobiosis stress. This paper explores soil conditions that exist because of waterlogging and submergence, reviews the current research of the effect ...
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Purpose: Significant research on yield improvement of wetland rice provided a greater understanding of stress physiology, but less on ecophysiology of anaerobiosis stress. This paper explores soil conditions that exist because of waterlogging and submergence, reviews the current research of the effect of the ecophysiology of abiotic stress, and the plant's adaptability through its various biochemical pathways and physiological processes. Findings: Rice has morphologically avoided anoxia due to flooding and submergence ecosystems through its aerenchyma tissues that facilitate oxygen diffusion from shoot to root-tips. The plant hormone system plays a central role in the initiation and regulation of most of these adaptive responses. The biochemical responses of submerged rice are mainly mechanisms of avoiding internal anoxia as the oxygen deficit shift the energy metabolism to anaerobic, with greater activity of glycolytic pathway, fermentation enzymes, and involvement of antioxidant defense mechanisms to cope with the post hypoxia/anoxia oxidative stress. Physiological processes including aerobic respiration, photosynthesis, and phytochrome photo-equilibrium of the submerged rice shoots have evolved to adapt to waterlogging stress. Most of the post-anoxic injury is due to the generation of reactive oxygen and toxic oxidative products as acetaldehyde, hydrogen peroxide and hydroxyl radical. Limitations: This was minimal due to accessibility to the literature. Directions for future research: Future research should be directed towards rice tolerance to waterlogging as well as low water availability and salinity.
Plant Stress
Seyedeh Laleh Alavi; Nasser Abbaspour
Abstract
Purpose: Soil salinity is a prevalent abiotic stress that adversely affects crop productivity worldwide. Salinity is an environmental stress that limits growth and development in fruits and vegetables due to increasing osmotic pressure, imbalancing of nutrients and toxicity of some special ions. Tomato ...
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Purpose: Soil salinity is a prevalent abiotic stress that adversely affects crop productivity worldwide. Salinity is an environmental stress that limits growth and development in fruits and vegetables due to increasing osmotic pressure, imbalancing of nutrients and toxicity of some special ions. Tomato (Lycopersicon esculentum) is one of the most important fruits and vegetables. Research method: In this study, effect of salt stress (NaCl) on eight cultivars of tomato (king stone, Caligen, Super Strain B, Primo Early, Early Urbana VF, Early Urbana 111, Cal-j-N3 and Peto Early CH) were investigated. Plants were cultured in hydroponic conditions with five treatments of NaCl including 0, 30, 60, 90 and 120 mM. Each test has repeated three times. The growth indices, Ions, chlorophyll, soluble sugar and proline contents, were measured in roots, stems, petioles and leaves. Main findings: The results showed that, sodium and chloride contents increased in all parts of the cultivars with increasing NaCl concentration. However nitrate and potassium contents decreased. Proline and soluble sugars contents increased in leaves under salt stress too. In Primo- Early, Early Urbana 111, Cal-j-N3 and Petoearly CH, soluble sugar content increased with increasing NaCl concentration up to 90 mM. In all varieties, high salinity reduced chlorophyll a and b, total chlorophyll, carotenoids contents and growth indices. As far as the measured factors are concerned, it seems that Early Urbana VF and Super Strain B showed a high capacity to tolerate salinity stress. Limitations: No limitations were founded. Originality/Value: This is an opportunity to identify salinity-tolerant tomato cultivars that play an important role in the cultivation and production of quality crops.
