Sulfate-Based Fertilizers Regulate Nutrient Uptake, Photosynthetic Gas Exchange, and Enzymatic Antioxidants to Increase Sunflower Growth and Yield Under Drought Stress

AbstractThe challenging impact of drought to agricultural productivity requires the adoption of mitigation strategies with a better understanding of underlying mechanisms responsible for drought tolerance. The present study aimed at investigating the effects of sulfur-based fertilizers on mitigation of drought stress in sunflower. Sulfate-containing fertilizers, viz., ammonium sulfate, zinc sulfate, magnesium sulfate, potassium sulfate, and gypsum, were initially evaluated at two different rates (10 and 20 mg kg−1 soil equivalent to 20 and 40 kg ha−1, respectively) for nutrient uptake and growth-promoting traits in sunflower seedlings (cv. Hysun-33). The best performing fertilizer (gypsum) was then selected to evaluate the response of sunflower under drought stress imposed at flowering stage for three weeks (25–30% water holding capacity). Results indicated significant amelioration of drought stress with higher activity of photosynthetic apparatus, upregulation of antioxidative enzymes, and increased achene yield by gypsum application. In comparison to control, gypsum-treated plants (20 mg kg−1 soil) exhibited higher water status (32%), leaf photosynthetic rate (29%), transpiration rate (67%), and stomatal conductance (118%) under drought stress. The antioxidant enzyme activities of catalase, guaiacol peroxidase, and superoxide dismutase were also increased by 67%, 62%, and 126%, respectively, resulting in higher achene yield (19%) under water-deficit conditions. This study indicates that the application of sulfur-based fertilizers (gypsum) can be used to induce drought tolerance and obtain high sunflower yields under drought stress, and furthermore, it is a cost-effective strategy resulting in high benefit–cost ratio with respect to no gypsum application.

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Overexpression of AtDREB1 and BcZAT12 Genes Confers Drought Tolerance by Reducing Oxidative Stress in Double Transgenic Tomato (Solanum Lycopersicum Mill.)

10.21203/rs.3.rs-378161/v1 ◽

2021 ◽

Author(s):

Ram Krishna ◽

Waquar Akhter Ansari ◽

Durgesh Kumar Jaiswal ◽

Ram Prasad ◽

JAY PRAKASH VERMA ◽

...

Keyword(s):

Antioxidant Enzymes ◽

Drought Stress ◽

Drought Tolerance ◽

Yield Potential ◽

Monodehydroascorbate Reductase ◽

Guaiacol Peroxidase ◽

Enzymatic Antioxidants ◽

Tomato Plants ◽

Element Binding Protein ◽

Responsive Element

Abstract A large number of genes has been targeted at the molecular level and transferred in tomato varieties from different sources for drought stress tolerance. Developed single transgenic (ST) plants exhibited better yield under drought stress, although the yield was comparatively lower and the plant growth was reduced. Hence, double transgenic plants were developed to improve yield potential without compromising drought tolerance; for this Dehydration Responsive Element Binding protein 1A (AtDREB1A) and Brassica carinata Zinc finger proteins (BcZAT12) genes were stacked. Developed double transgenic (DT) tomato plants by co-over expressing of both the genes exhibited more enzymatic and non-enzymatic antioxidative activities than control. Double transgenic (DZ1-DZ5) tomato lines, co-overexpressing AtDREB1A and BcZAT12 showed enhanced drought tolerance than their counterpart and wild type (WT) plants at 0, 07, 14, and 21 days of water deficit (DWD), respectively. DT plants showed increased activity of antioxidant enzymes, like catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), monodehydroascorbate reductase (MDHAR) and guaiacol peroxidase (POD) and accumulation of non-enzymatic antioxidants like ascorbic acid, glutathione as compared to ST and WT. Additionally, the transcript analysis of antioxidant enzymes revealed the level of gene expression in DT tomato plants. In the present study, co-overexpression of AtDREB1A and BcZAT12 genes in tomato showed superior drought tolerance as compared to ST and WT by elevating activity and quantity of enzymatic and non-enzymatic antioxidants. This is the primary report in tomato, which forms the basis for a multigene transgenic approach to cope with drought stress.

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Research Progress and Perspective on Drought Stress in Legumes: A Review

International Journal of Molecular Sciences ◽

10.3390/ijms20102541 ◽

2019 ◽

Vol 20 (10) ◽

pp. 2541 ◽

Cited By ~ 29

Author(s):

Muhammad Nadeem ◽

Jiajia Li ◽

Muhammad Yahya ◽

Alam Sher ◽

Chuanxi Ma ◽

...

Keyword(s):

Water Stress ◽

Drought Stress ◽

Nutrient Uptake ◽

Nutrient Management ◽

Growth Parameters ◽

Photosynthetic Apparatus ◽

Net Photosynthesis ◽

Research Progress ◽

Drought Tolerant ◽

The Impact

Climate change, food shortage, water scarcity, and population growth are some of the threatening challenges being faced in today’s world. Drought stress (DS) poses a constant challenge for agricultural crops and has been considered a severe constraint for global agricultural productivity; its intensity and severity are predicted to increase in the near future. Legumes demonstrate high sensitivity to DS, especially at vegetative and reproductive stages. They are mostly grown in the dry areas and are moderately drought tolerant, but severe DS leads to remarkable production losses. The most prominent effects of DS are reduced germination, stunted growth, serious damage to the photosynthetic apparatus, decrease in net photosynthesis, and a reduction in nutrient uptake. To curb the catastrophic effect of DS in legumes, it is imperative to understand its effects, mechanisms, and the agronomic and genetic basis of drought for sustainable management. This review highlights the impact of DS on legumes, mechanisms, and proposes appropriate management approaches to alleviate the severity of water stress. In our discussion, we outline the influence of water stress on physiological aspects (such as germination, photosynthesis, water and nutrient uptake), growth parameters and yield. Additionally, mechanisms, various management strategies, for instance, agronomic practices (planting time and geometry, nutrient management), plant growth-promoting Rhizobacteria and arbuscular mycorrhizal fungal inoculation, quantitative trait loci (QTLs), functional genomics and advanced strategies (CRISPR-Cas9) are also critically discussed. We propose that the integration of several approaches such as agronomic and biotechnological strategies as well as advanced genome editing tools is needed to develop drought-tolerant legume cultivars.

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Exogenous Melatonin Modulates the Physiological and Biochemical Mechanisms of Drought Tolerance in Tartary Buckwheat (Fagopyrum tataricum (L.) Gaertn)

Molecules ◽

10.3390/molecules25122828 ◽

2020 ◽

Vol 25 (12) ◽

pp. 2828

Author(s):

Md. Shakhawat Hossain ◽

Jing Li ◽

Ashim Sikdar ◽

Mirza Hasanuzzaman ◽

Ferdinand Uzizerimana ◽

...

Keyword(s):

Drought Stress ◽

Plant Growth ◽

Sugar Content ◽

Soluble Sugar ◽

Growth And Yield ◽

Tartary Buckwheat ◽

Arid Zones ◽

Enzymatic Antioxidants ◽

Fagopyrum Tataricum ◽

Exogenous Melatonin

Tartary buckwheat is one of the nutritious minor cereals and is grown in high-cold mountainous areas of arid and semi-arid zones where drought is a common phenomenon, potentially reducing the growth and yield. Melatonin, which is an amphiphilic low molecular weight compound, has been proven to exert significant effects in plants, under abiotic stresses, but its role in the Tartary buckwheat under drought stress remains unexplored. We evaluated the influence of melatonin supplementation on plant morphology and different physiological activities, to enhance tolerance to posed drought stress by scavenging reactive oxygen species (ROS) and alleviating lipid peroxidation. Drought stress decreased the plant growth and biomass production compared to the control. Drought also decreased Chl a, b, and the Fv/Fm ratio by 54%, 70%, and 8%, respectively, which was associated with the disorganized stomatal properties. Under drought stress, H2O2, O2•−, and malondialdehyde (MDA) contents increased by 2.30, 2.43, and 2.22-folds, respectively, which caused oxidative stress. In contrast, proline and soluble sugar content were increased by 84% and 39%, respectively. However, exogenous melatonin (100 µM) could improve plant growth by preventing ROS-induced oxidative damage by increasing photosynthesis, enzymatic antioxidants (superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase), secondary metabolites like phenylalanine ammonialyase, phenolics, and flavonoids, total antioxidant scavenging (free radical DPPH scavenging), and maintaining relative water content and osmoregulation substances under water stress. Therefore, our study suggested that exogenous melatonin could accelerate drought resistance by enhancing photosynthesis and antioxidant defense in Tartary buckwheat plants.

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Effects of exogenous abscisic acid on foliar anthocyanin accumulation and drought tolerance in purple rice

Biologia ◽

10.1515/biolog-2015-0107 ◽

2015 ◽

Vol 70 (7) ◽

Cited By ~ 3

Author(s):

Parinyaphorn Ploenlap ◽

Wattana Pattanagul

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Reproductive Organs ◽

Antioxidant Enzyme Activities ◽

Rice Cultivars ◽

Anthocyanin Accumulation ◽

Exogenous Aba ◽

Antioxidant Mechanism ◽

Effects Of Drought ◽

Dpph Scavenging

AbstractThe effects of drought and exogenous ABA on foliar anthocyanin accumulation and its role in drought tolerance were studied in two purple rice cultivars GS. No. 00621 and GS. No. 21427. The seedlings were grown for 14 days and separated into four groups including control (well-watered), drought (withholding water), ABA (foliar sprayed with 20 mg L−1 ABA and well-watered), ABA and drought (foliar sprayed with 20 mg L−1 ABA and withholding water). Drought was imposed by withholding water for 7 days. The results showed that drought significantly reduced root and shoot growth in GS. No. 00621, while had little effect on GS. No. 21427. Drought stress also induced anthocyanin overaccumulation in GS. No. 21427, whereas its content was reduced in GS. No. 00621. Exogenous ABA had no effect on anthocyanin in both wellwatered and drought conditions in both cultivars. Higher anthocyanin in GS. No. 21427 was coincided with higher DPPH scavenging ability, antioxidant enzyme activities as well as higher relative water content. It is, therefore, concluded that drought-induced anthocyanin overaccumulation may be different between purple rice cultivars and anthocyanin is beneficial for the response to drought stress by protecting plant antioxidant mechanism. Unlike anthocyanin in plant reproductive organs, exogenous ABA has no effect on foliar anthocyanin accumulation in purple rice. It is possible that anthocyanin accumulation in leaf and reproductive organs may be regulated differently or triggered by different mechanisms.

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Exogenous Application of Melatonin Improves Drought Tolerance in Coffee by Regulating Photosynthetic Efficiency and Oxidative Damage

Journal of the American Society for Horticultural Science ◽

10.21273/jashs04964-20 ◽

2021 ◽

Vol 146 (1) ◽

pp. 24-32

Author(s):

Sylvia Cherono ◽

Charmaine Ntini ◽

Misganaw Wassie ◽

Mohammad Dulal Mollah ◽

Mohammad A. Belal ◽

...

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Oxidative Damage ◽

Photosynthetic Efficiency ◽

Crop Yields ◽

Foliar Spray ◽

Chlorophyll Degradation ◽

Guaiacol Peroxidase ◽

Protective Agent ◽

Exogenous Application

The protective role of melatonin in plants under abiotic stress has been reported, but little information is available on its mitigation effect on coffee (Coffea arabica) plants. The objective of this study was to determine the effect of exogenous application of 100 µM melatonin in coffee leaves under 3 months of drought stress treatment. Melatonin was found to alleviate the drought-induced damage in coffee through reducing the rate of chlorophyll degradation, electrolyte leakage, malonaldehyde content, and activating various antioxidant enzymes, such as catalase, guaiacol peroxidase, and superoxide dismutase. Melatonin application suppressed the expression of chlorophyll degradation gene PAO encoding pheophorbide a oxygenase, and upregulated the expression of photosynthetic gene RBCS2 encoding ribulose-1,5-bisphosphate oxygenase (Rubisco) protein, and a drought-related gene AREB encoding abscisic acid-responsive element binding protein. The photosynthetic efficiency of photosystem II under dark adaptation was also improved upon melatonin application in drought-stressed plants. Our results showed that both foliar spray and direct soil application of melatonin could improve drought tolerance by regulating photosynthetic efficiency and oxidative damage in C. arabica seedlings. This study provides insights in application of melatonin as a protective agent against drought stress in improvement of crop yields.

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Physiological and Proteomic Analysis Revealed the Response Mechanisms of two Different Grought-resistant Maize Varieties

10.21203/rs.3.rs-630007/v1 ◽

2021 ◽

Author(s):

Hongjie Li ◽

Mei Yang ◽

Chengfeng Zhao ◽

Yifan Wang ◽

Renhe Zhang

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Stress Responses ◽

Molecular Chaperones ◽

Electron Flow ◽

Photochemical Efficiency ◽

Growth And Yield ◽

Protective Mechanism ◽

Drought Tolerant ◽

Maize Varieties

Abstract Background: Drought stress seriously limits the seedling growth and yield of maize. Despite previous studies on drought resistance mechanisms by which maize cope with water deficient, the link between physiological and molecular variations are largely unknown. To reveal the complex regulatory mechanisms, comparative physiology and proteomic analyses were conducted to investigate the stress responses of two maize cultivars with contrasting tolerance to drought stress. Results: Physiological results showed that SD609 (drought-tolerant) maintains higher photochemical efficiency by enhancing CEF (cyclic electron flow) protective mechanism and antioxidative enzymes activities. Proteomics analysis revealed a total of 198 and 102 proteins were differentially expressed in SD609 and SD902, respectively. Further enrichment analysis indicated that drought-tolerant ‘SD609’ increased the expression of proteins related to photosynthesis, antioxidants/detoxifying enzymes, molecular chaperones and metabolic enzymes. The up-regulation proteins related to PSII repair and photoprotection mechanisms resulted in more efficient photochemical capacity in tolerant variety under moderate drought. However, the drought-sensitive ‘SD902’ only induced molecular chaperones and sucrose synthesis pathways, and failed to protect the impaired photosystem. Further analysis indicated that proteins related to the electron transport chain, redox homeostasis and heat shock proteins (HSPs) could be important in protecting plants from drought stress. Conclusions: Our experiments explored the mechanism of drought tolerance, and obtained detailed information about the interconnection of physiological research and protein research. In summary, our findings could provide new clues into further understanding of drought tolerance mechanisms in maize.

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Pengaruh biostimulan terhadap toleransi kekeringan dan pertumbuhan tanaman tebu varietas Kidang Kencana di rumah kaca (Effect of biostimulants on drought tolerance and growth of sugarcane var. Kidang Kencana at green house)

E-Journal Menara Perkebunan ◽

10.22302/iribb.jur.mp.v1i1.287 ◽

2018 ◽

Vol 86 (1) ◽

Author(s):

Dian Mutiara AMANAH ◽

Soekarno Mismana PUTRA

Keyword(s):

Drought Stress ◽

Humic Acid ◽

Drought Tolerance ◽

Plant Height ◽

Vegetative Growth ◽

Sugar Yield ◽

Stress Conditions ◽

Growth And Yield ◽

Segment Number ◽

Increasing Demand

Increasing productivity and sugar yield of sugarcane are required to meet the increasing demand for sugar. Biostimulants application is one of the effort to increase the productivity and rendement of sugar, especially at drought stress conditions. The purpose of this study was to determine the effect of biostimulants on the performance of sugarcane var. Kidang Kencana known susceptible to drought stress. The research was conducted in the greenhouse with several biostimulant treatments i.e. P0: Control, P1: Citorin-R, P2: Citorin-R and Citorin-S (1x spray) P3: Citorin-R and Citorin -S (2x spray), P4: Citorin-R, Citorin-S (1x spray) and Humic Acid, P5: Citorin-R, Citorin-S (1x spray), Humic Acid and Mycorrhiza, P6: Citorin-R, Citorin-S (2x spray), Humic Acid and Mycorrhiza. All treatments were subjected with drought stress started from 4 months after planting. The biostimulant treatments resulted in better growth and yield on treated-biostimulan compared to these of control. The best treatment for the vegetative growth and the productive parameters was P6. The plant height, stems diameter, segment number, weight, and sap volume at P6 were respectively 32.2%, 5.5%, 24.0%, 53.2% and 44.7% higher than the control. The best treatment for the sugar yield was P5 and the productivity parameters was P6 respectively, 42.5% and 70.5% higher than the control. The best treatments contained Citorin biostimulant. Humic Acid and Mycorrhiza which increased growth and sugar yield of Kidang Kencana sugarcane at drought stress conditions.[Keywords: drought stress Kidang Kencana variety, plant biostimulant, productivity, sugar yield]. AbstrakPeningkatan produktivitas dan rendemen gula tanaman tebu diperlukan untuk memenuhi kebutuhan gula yang terus meningkat. Aplikasi biostimulan merupakan salah satu upaya untuk meningkatkan produktivitas dan rendemen gula khususnya pada kondisi tercekam kekeringan. Tujuan dari penelitian ini adalah untuk mengetahui pengaruh pemberian beberapa produk biostimulan terhadap produktivitas tanaman tebu varietas Kidang Kencana yang rentan cekaman kekeringan. Penelitian dilakukan di rumah kaca dengan perlakuan beberapa perlakuan biostimulan pada tanaman tebu, yaitu P0: Kontrol, P1: Citorin-R, P2: Citorin-R dan Citorin-S (1x semprot) P3: Citorin-R dan Citorin-S (2x semprot), P4: Citorin-R, Citorin-S (1x semprot) dan Asam Humat, P5: Citorin-R, Citorin-S (1x semprot), Asam Humat dan Mikoriza, P6: Citorin-R, Citorin-S (2x semprot), Asam Humat dan Mikoriza. Seluruh perlakuan diberi kondisi cekaman kekeringan pada 4 bulan setelah tanam. Perlakuan biostimulan memberikan pengaruh serta hasil yang lebih baik dibandingkan dengan kontrol baik fase vegetatif maupun produktif. Perlakuan terbaik selama fase vegetatif hingga 5 bulan setelah tanam adalah P6. Tinggi batang panen, diameter batang panen, jumlah ruas batang, bobot batang dan volume nira pada P6 meningkat 32,2%, 5,5%, 24,0%, 53,2% dan 44,7% lebih tinggi dibandingkan dengan kontrol. Perlakuan terbaik untuk parameter rendemen gula adalah P5 dan produktivitas gula adalah P6, masing-masing 42,5% dan 70,5% lebih tinggi dibandingkan kontrol. Perlakuan terbaik tersebut mengandung komponen biostimulan yaitu Citorin, Asam Humat dan Mikoriza yang dapat meningkatkan pertumbuhan dan rendemen gula tanaman tebu Kidang Kencana pada kondisi cekaman kekeringan. [Kata kunci: cekaman kekeringan, varietas Kidang Kencana, biostimulan tanaman, produktivitas, rendemen gula].

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Drought Effects on Growth, Water Content, and Organic Osmoprotectants in Promising Almond Genotypes with Different Drought Tolerance

10.21203/rs.3.rs-206134/v1 ◽

2021 ◽

Author(s):

Shabnam Gohari ◽

Ali Imani ◽

AliReza Talaei ◽

Vahid Abdossi ◽

Mohamad Reza Asghari

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Water Content ◽

Light Stress ◽

Stress Conditions ◽

Growth And Yield ◽

Leaf Water Content ◽

Severe Stress ◽

Drought Adaptation ◽

Genotype A

Abstract Background Almonds ( Prunus amygdalus Batsch, syn. P. dulcis (Mill.) DA Webb) is a valuable nut crops species that is widely is cultivated in arid and semi-arid regions of Iran, due to drought tolerance and dehydration under drought stress. Almonds show physiological adaptations for survival in drought stress conditions, but the degree Drought adaptation varies between cultivars. However, to date, its morphological and physiological responses to drought, and the underlying mechanisms are not well understood. This study was aimed to investigate the morphological and physiological changes of almond genotypes under drought stress. almond genotypes were planted in pots and subjected to four levels of soil water treatments: above 80% (control), 60% (light stress), and 40% (severe stress) of field capacity. Results Within the total stress period (0–30 days), almond genotypes grew rapidly in the light stress, whereas severe stress had a negative impact on growth. So that, in this study, 10 selected almond genotypes using some morphological traits such as: plant height, trunk diameter at the top of the graft, new branch growth length, leaf yellowness and some physiological indicators under drought stress conditions such as Chlorophyll index was evaluated based on SPAD criterion, relative leaf water content, measurement of chlorophyll fluorescence and Organic Osmoprotectants to identify drought-resistant and sensitive genotypes under drought stress conditions. Among the selected genotypes studied, genotype A-7-100 was the most resistant and genotype A-124-1 was the most sensitive to drought stress. Conclusions Our results show that almond genotypes adapt to drought mainly by avoidance mechanisms, and its morphological and physiological characteristics are inhibited under severe stress, However, the degree of drought adaptation varies between different cultivars. These findings might help limited water resources to be fully used for increased the percentage of kernel and finally increased the growth and yield of plants under water stress.

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Transcriptome Analysis Revealed GhWOX4 Intercedes Myriad Regulatory Pathways to Modulate Drought Tolerance and Vascular Growth in Cotton

International Journal of Molecular Sciences ◽

10.3390/ijms22020898 ◽

2021 ◽

Vol 22 (2) ◽

pp. 898

Author(s):

Muhammad Sajjad ◽

Xi Wei ◽

Lisen Liu ◽

Fuguang Li ◽

Xiaoyang Ge

Keyword(s):

Transcription Factors ◽

Drought Stress ◽

Drought Tolerance ◽

Plant Growth ◽

Growth And Development ◽

Differentially Expressed ◽

Growth And Yield ◽

Regulatory Pathways ◽

Vascular Growth

Cotton is a paramount cash crop around the globe. Among all abiotic stresses, drought is a leading cause of cotton growth and yield loss. However, the molecular link between drought stress and vascular growth and development is relatively uncharted. Here, we validated a crucial role of GhWOX4, a transcription factor, modulating drought stress with that of vasculature growth in cotton. Knock-down of GhWOX4 decreased the stem width and severely compromised vascular growth and drought tolerance. Conversely, ectopic expression of GhWOX4 in Arabidopsis enhanced the tolerance to drought stress. Comparative RNAseq analysis revealed auxin responsive protein (AUX/IAA), abscisic acid (ABA), and ethylene were significantly induced. Additionally, MYC-bHLH, WRKY, MYB, homeodomain, and heat-shock transcription factors (HSF) were differentially expressed in control plants as compared to GhWOX4-silenced plants. The promotor zone of GhWOX4 was found congested with plant growth, light, and stress response related cis-elements. differentially expressed genes (DEGs) related to stress, water deprivation, and desiccation response were repressed in drought treated GhWOX4-virus-induced gene silencing (VIGS) plants as compared to control. Gene ontology (GO) functions related to cell proliferation, light response, fluid transport, and flavonoid biosynthesis were over-induced in TRV: 156-0 h/TRV: 156-1 h (control) in comparison to TRV: VIGS-0 h/TRV: VIGS-1 h (GhWOX4-silenced) plants. This study improves our context for elucidating the pivotal role of GhWOX4 transcription factors (TF), which mediates drought tolerance, plays a decisive role in plant growth and development, and is likely involved in different regulatory pathways in cotton.

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α-Tocopherol Foliar Spray and Translocation Mediates Growth, Photosynthetic Pigments, Nutrient Uptake, and Oxidative Defense in Maize (Zea mays L.) under Drought Stress

Agronomy ◽

10.3390/agronomy10091235 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1235

Author(s):

Qasim Ali ◽

Muhammad Tariq Javed ◽

Muhammad Zulqurnain Haider ◽

Noman Habib ◽

Muhammad Rizwan ◽

...

Keyword(s):

Lipid Peroxidation ◽

Water Stress ◽

Drought Tolerance ◽

Nutrient Uptake ◽

Defense Mechanism ◽

Foliar Application ◽

Photosynthetic Pigment ◽

Foliar Spray ◽

Enzymatic Antioxidants ◽

Maize Cultivars

A pot experiment was conducted to assess the induction of drought tolerance in maize by foliar-applied α-tocopherol at early growth stage. Experiment was comprised two maize cultivars (Agaiti-2002 and EV-1098), two water stress levels (70% and 100% field capacity), and two α-tocopherol levels (0 mmol and 50 mmol) as foliar spray. Experiment was arranged in a completely randomized design in factorial arrangement with three replications of each treatment. α-tocopherol was applied foliary at the early vegetative stage. Water stress reduced the growth of maize plants with an increase in lipid peroxidation in both maize cultivars. Contents of non-enzymatic antioxidants and activities of antioxidant enzymes increased in studied plant parts under drought, while the nutrient uptake was decreased. Foliary-applied α-tocopherol improved the growth of both maize cultivars, associated with improvements in photosynthetic pigment, water relations, antioxidative mechanism, and better nutrient acquisition in root and shoot along with tocopherol contents and a decrease in lipid peroxidation. Furthermore, the increase of tocopherol levels in roots after α-Toc foliar application confers its basipetal translocation. In conclusion, the findings confer the role of foliar-applied α-tocopherol in the induction of drought tolerance of maize associated with tissue specific improvements in antioxidative defense mechanism through its translocation.

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