Is seaweed extract an elicitor compound? Changing  proline content in drought-stressed bean plants

Abiotic stresses negatively affect crop development and yield. However, the use of seaweed extracts can alleviate production losses through improvement of the antioxidant system and synthesis of compatible osmolytes. The aim of this study was to assess the effects of Ascophyllum nodosum extract on antioxidant response and yield of common bean plants (Phaseolus vulgaris) under drought stress. Therefore, two methods of application (foliar spray and soil irrigation) and two doses (5 and 10 mL L-1) were tested, whereas untreated plants were used as control. There were no significant differences in malondialdehyde and hydrogen peroxide contents among treatments, indicating that application of seaweed extract did not change the oxidative status in treated plants when compared to the control ones. On the other hand, the use of seaweed extract increased proline content even prior to drought stress (46.3 to 145.4% when compared to the control), and this increment remained until the 10th day of stress (from 60.1 to 201.7% over the reference plants), supporting early evidences that A. nodosum extract is a plant elicitor. The yield parameters were not affected by the extract, probably due to the severe drought stress which plants were submitted. The results suggest that A. nodosum extract affects proline metabolism in Phaseolus vulgaris plants, making the synthesis of this osmolyte more responsive to drought stress because seaweed-treated plants presented a higher proline content than the control ones during the exposure to water deficit.

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Applications of a Commercial Extract of the Brown Seaweed Ascophyllum nodosum Increases Drought Tolerance in Container-grown ‘Hamlin’ Sweet Orange Nursery Trees

HortScience ◽

10.21273/hortsci.46.4.577 ◽

2011 ◽

Vol 46 (4) ◽

pp. 577-582 ◽

Cited By ~ 38

Author(s):

Timothy M. Spann ◽

Holly A. Little

Keyword(s):

Drought Stress ◽

Sweet Orange ◽

Foliar Spray ◽

Brown Seaweed ◽

Ascophyllum Nodosum ◽

Seaweed Extract ◽

Plant Water ◽

Stem Water Potential ◽

Soil Drench ◽

Commercial Extract

‘Hamlin’ sweet orange trees on ‘Carrizo’ citrange and ‘Swingle’ citrumelo rootstocks were treated weekly with a commercial extract of the brown seaweed Ascophyllum nodosum at 5 and 10 mL·L−1 as either a soil drench or foliar spray. Half of the trees in each treatment were subjected to drought stress [irrigated at 50% of evapotranspiration (ET)], whereas the other half remained fully irrigated (100% ET). Drought stress reduced shoot growth and leaf photosynthesis but increased root and total plant growth relative to the amount of water applied, thus increasing whole plant water use efficiency. Trees treated with seaweed extract and drought-stressed had significantly more total growth than untreated drought-stressed trees for both rootstocks. The maintenance of growth by the seaweed extract under drought stress conditions was unrelated to photosynthesis. However, the seaweed extract treatment did have a significant effect on plant water relations. Soil drench-treated trees had more growth and higher stem water potential than foliar-treated or control trees after 8 weeks of drought stress. These results indicate that seaweed extract may be a useful tool for improving drought stress tolerance of container-grown citrus trees.

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Melatonin Promotes SGT1-Involved Signals to Ameliorate Drought Stress Adaption in Rice

International Journal of Molecular Sciences ◽

10.3390/ijms23020599 ◽

2022 ◽

Vol 23 (2) ◽

pp. 599

Author(s):

Ruiqing Li ◽

Ruifang Yang ◽

Wenyin Zheng ◽

Liquan Wu ◽

Can Zhang ◽

...

Keyword(s):

Drought Stress ◽

Antioxidant System ◽

Survival Rates ◽

Foliar Spray ◽

Underlying Mechanism ◽

Severe Drought ◽

Environmental Threats ◽

Expression Of Genes ◽

Osmotic Balance ◽

Agriculture And Food

Drought has become one of the environmental threats to agriculture and food security. Applications of melatonin (MT) serve as an effective way to alleviate drought stress, but the underlying mechanism remains poorly understood. Here, we found that foliar spray of 100-µM MT greatly mitigated the severe drought stress-induced damages in rice seedlings, including improved survival rates, enhanced antioxidant system, and adjusted osmotic balance. However, mutation of the suppressor of the G2 allele of skp1 (OsSGT1) and ABSCISIC ACID INSENSITIVE 5 (OsABI5) abolished the effects of MT. Furthermore, the upregulated expression of OsABI5 was detected in wild type (WT) under drought stress, irrespective of MT treatment, whereas OsABI5 was significantly downregulated in sgt1 and sgt1abi5 mutants. In contrast, no change of the OsSGT1 expression level was detected in abi5. Moreover, mutation of OsSGT1 and OsABI5 significantly suppressed the expression of genes associated with the antioxidant system. These results suggested that the functions of OsSGT1 in the MT-mediated alleviation of drought stress were associated with the ABI5-mediated signals. Collectively, we demonstrated that OsSGT1 was involved in the drought response of rice and that melatonin promoted SGT1-involved signals to ameliorate drought stress adaption.

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Alleviation of adverse effects of drought stress on common bean (Phaseolus vulgaris L.) by exogenous application of hydrogen peroxide

Bangladesh Journal of Botany ◽

10.3329/bjb.v40i1.8001 ◽

1970 ◽

Vol 40 (1) ◽

pp. 75-83 ◽

Cited By ~ 16

Author(s):

Salwa Mohamed Abass ◽

Heba Ibrahim Mohamed

Keyword(s):

Hydrogen Peroxide ◽

Drought Stress ◽

Phaseolus Vulgaris ◽

Common Bean ◽

Growth Parameters ◽

Compatible Solutes ◽

Seed Pretreatment ◽

Bean Plants ◽

Effects Of Drought ◽

Common Bean Plants

Effects of seed pretreatment by hydrogen peroxide (H2O2) on drought tolerance in common bean plants (Phaseolus vulgaris L.) were studied. Drought stress caused highly significant decrease in growth parameters, photosynthetic pigments, total carbohydrates and phytohormones. An increase drought stress caused highly significant increase in compatible solutes and polyamine contents as antioxidants and ABA contents in shoots of common bean plants. H2O2-pretreatment of seeds enhanced all the above parameters than the waterpretreated seeds (control) under drought condition. Results suggested that H2O2, a stress signal could trigger the activation of antioxidants in seeds which persists in the plants to alleviate the oxidative damage leading to improvements in physiological attributes for the plants growth under drought. Key words: Drought; Phaseolus vulgaris; Common bean; Advanced effect; Hydrogen peroxide DOI: http://dx.doi.org/10.3329/bjb.v40i1.8001 Bangladesh J. Bot. 40(1): 75-83, 2011 (June)

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Foliar Sprayed Green Zinc Oxide Nanoparticles Mitigate Drought-Induced Oxidative Stress in Tomato

Plants ◽

10.3390/plants10112400 ◽

2021 ◽

Vol 10 (11) ◽

pp. 2400

Author(s):

Manal El-Zohri ◽

Naseem A. Al-Wadaani ◽

Sameera O. Bafeel

Keyword(s):

Oxidative Stress ◽

Zinc Oxide ◽

Drought Stress ◽

Zinc Oxide Nanoparticles ◽

Foliar Spray ◽

Oxide Nanoparticles ◽

Severe Drought ◽

Zno Nps ◽

Drought Conditions ◽

Tomato Growth

This study explored the effectiveness of green zinc oxide nanoparticles (ZnO-NPs) foliar spray on tomato growth and oxidative stress relief under drought conditions. Tomato plant subjected to four water regimes (100, 75, 50, and 25% FC), and in the same while seedlings were sprayed with 25, 50, and 100 mg/L green ZnO-NPs. The results showed that tomato growth parameters reduced significantly by increasing drought stress levels, while ZnO-NPs enhanced plant growth under all studied drought levels. Out of three ZnO-NPs concentrations tested, 25 and 50 mg/L ZnO-NPs proved to be the optimum treatments for alleviating drought stress. They increased shoot and root biomass compared to untreated controls. Application of 25 and 50 mg/L ZnO-NPs enhanced shoot dry weight by about 2–2.5-fold, respectively, under severe drought conditions (25%) compared to ZnO-NPs untreated plants. The application of 25 and 50 mg/L green ZnO-NPs decreased the drought-induced oxidative stress as indicated by the reduction in malondialdehyde and hydrogen peroxide concentrations compared to untreated controls. While 100 mg/L ZnO-NPs further increased oxidative stress. The beneficial effects of ZnO-NPs were evident in the plants’ defensive state, in which the concentration of ascorbic acid, free phenols, and the activity of superoxide dismutase, catalase, and ascorbate peroxidase were maintained at higher levels compared to NPs-untreated plants. At severe drought conditions, 25 mg/L ZnO-NPs induced SOD, CAT, and APX activity by about 3.99-, 3.23-, and 2.82-fold of their corresponding controls, respectively. Likewise, at 25% FC, SOD, CAT, and APX activity increased with 50 mg/L ZnO-NPs by about 4.58-, 3.57-, and 3.25-fold consecutively compared with their respective controls. Therefore, foliar use of green ZnO-NPs at lower concentrations might be suggested as an efficient way for enhancing tomato tolerance to drought stress.

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Influence of Storage Temperature and Duration of Tomato Leaf Samples on Proline Content

European Scientific Journal ESJ ◽

10.19044/esj.2017.v13n6p116 ◽

2017 ◽

Vol 13 (6) ◽

pp. 116

Author(s):

Mohammad H. Brake ◽

Hassan R. Hamasha ◽

Hussein M. Migdadi ◽

Ashraf O. Khashroum ◽

Moath Al-Gharaibeh ◽

...

Keyword(s):

Drought Stress ◽

Agricultural Development ◽

Storage Temperature ◽

Field Method ◽

Economic Benefits ◽

Proline Content ◽

Severe Drought ◽

Agricultural Crop ◽

Free Proline ◽

The Impact

In arid and semi-arid countries such as Jordan, shortage in water sources might affect agricultural development and reduces the effectiveness of economic benefits of most crops planted in such areas. Tomato is an important agricultural crop and faces severe drought stress due to climate changes, therefore, measurement of proline accumulation in plant tissues is used as an indicator for drought stress tolerance. This research was conducted at Jarash University Campus in northern Jordan. A field experiment was carried out to investigate the impact of different storage temperature (+4ºC, - 20ºC and -80ºC) and different storage durations (0, 3, 6 and 11 weeks) on proline content in five different Jordanian tomato landraces. Results indicated that the average free proline content for samples tested directly after leaves collection was 7.1 µmol/g. Proline content in leaves stored at +4 ºC for 3, 6, and 11 weeks was 4.8, 1.8, and 1.1µmol/g, respectively, while for -20ºC was 11.8, 7.9, and 9.5 µmol/g for samples stored for 3, 6, 11 weeks respectively. In contrast the highest values for these parameters were obtained from samples stored at -80ºC, the average measured values of free proline content were 9.5, 7.8, and 12.9 µmol/g at 3, 6, and 11 weeks of storage, respectively. Based on the results obtained by this research, it is recommended to measure proline content directly after leaves collection. However, for large number of samples, keeping the samples at -20ºC not longer than six weeks could be a solution. Finally, we highly recommend the development of in-field method for measurement of free proline content.

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ASCOPHYLLUM NODOSUM SEAWEED EXTRACT EFFECT ON DROUGHT STRESS IN BEAN PLANTS

17th International Multidisciplinary Scientific GeoConference SGEM2017, Nano, Bio and Green � Technologies for a Sustainable Future ◽

10.5593/sgem2017h/63/s25.017 ◽

2017 ◽

Author(s):

Monica Popescu

Keyword(s):

Drought Stress ◽

Ascophyllum Nodosum ◽

Seaweed Extract ◽

Bean Plants

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Different Drought-Tolerant Mechanisms in Quinoa (Chenopodium quinoa Willd) and Djulis (Chenopodium formosanum Koidz.) Based on Physiological Analysis

Plants ◽

10.3390/plants10112279 ◽

2021 ◽

Vol 10 (11) ◽

pp. 2279

Author(s):

Pin-Hua Lin ◽

Yun-Yang Chao

Keyword(s):

Drought Stress ◽

Water Content ◽

Sugar Content ◽

Soluble Sugar ◽

Soluble Sugars ◽

Chenopodium Quinoa ◽

Proline Content ◽

Severe Drought ◽

Drought Treatment ◽

Total Soluble Sugar

The purpose of this experiment is to study the effects of treatment with 90% (28.5% volumetric water content (VWC)), 75% (24% VWC), 50% (16% VWC), and 25% (8% VWC) of water requirements on the growth of two djulis (Chenopodium formosana Koidz) varieties (red: RP and yellow: OR) and one quinoa (Chenopodium quinoa Willd) varieties (PI). The results showed that drought stress (8% VWC) significantly reduced plant growth and relative water content, and increased H2O2 and MDA content in C. formosana and C. quinoa. The most significant increase in these parameters was detected in the OR variety. The antioxidant enzymes, such as SOD, APX, and GR activities of PI variety under drought treatment (8% VWC), are significantly increased, while GR activity of C. formosana also increased significantly. Additionally, C. formosana and PI variety remained at a stable AsA/DHA ratio, but the GSH/GSSG ratio decreased during drought treatment. Moreover, drought stress increased total soluble sugars and proline content in the PI variety. However, C. formosana proline content was extremely significantly enhanced, and only the OR variety increased the total soluble sugar content at the same time during the vegetative growth period. In summary, C. formosana and C. quinoa have different drought tolerance mechanisms to adapt to being cultivated and produced under severe drought conditions.

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Early assessment of drought tolerance in oil palm D × P progenies using growth and physiological characters in seedling stage

Plant Genetic Resources ◽

10.1017/s1479262118000151 ◽

2018 ◽

Vol 16 (6) ◽

pp. 544-554 ◽

Cited By ~ 1

Author(s):

Saowapa Duangpan ◽

Pimchanok Buapet ◽

Satanan Sujitto ◽

Theera Eksomtramage

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Oil Palm ◽

Growth Traits ◽

Proline Content ◽

Rapid Screening ◽

Tolerance Index ◽

Severe Drought ◽

Early Assessment ◽

Moderate Drought

AbstractDrought is a major constraint to oil palm plantation in many regions relying on rainfall. One strategy to overcome this problem is to develop drought-tolerant cultivars through screening and selection. Drought tolerance assessment based on growth and physiological traits provides an alternative approach for rapid screening especially in tree crops. The aims of this study were to determine the contribution of some growth and physiological parameters to drought response variation in oil palm seedling and to use those parameters to evaluate relative drought stress tolerance in tenera oil palm progenies. Eight D × P progenies were grown under well-watered, moderate and severe stressed conditions for a total of 6 months. Data on growth traits, maximum quantum yield (Fv/Fm), SPAD value and proline content were recorded. Principal component analysis (PCA) on studied traits revealed that PC1 and PC2 explained 74.57 and 76.80% of total variance in moderate and severe drought treatments, respectively. Major contributions towards the variation of control and drought-treated plants were identified and appeared to be growth traits in moderate drought stress and growth trait plus proline content in severe drought stress. According to drought tolerance index, PCA analysis and ranking method using integrated PCA values, PSU-106 and PSU-206 were identified to be relatively high tolerant to severe drought stress, while PSU-106, PSU-128, PSU-206 and PSU-208 were tolerant to moderate drought stress. Field validation of D × P progenies selected as drought tolerance is recommended to establish this indirect selection approach in oil palm breeding programme.

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