‘Garnem’ and Myrobalan ‘P.2175’: Two Different Drought Responses and Their Implications in Drought Tolerance

One of the challenges in rootstock breeding programs is the combination of tolerances to different abiotic stresses in new interspecific hybrids adapted to a wide range of environmental conditions. In this work, two Prunus L. rootstocks: Myrobalan ‘P.2175’ (P. cerasifera Ehrh.) and the almond × peach hybrid ‘Garnem’ (P. amygdalus Batsch × P. persica (L.) Batsch) were subjected to drought during 24 h to understand their drought response mechanisms. The study was conducted monitoring leaf water potential (LWP), stomatal conductance (gs), relative water content (RWC), and electrolyte leakage (EL); as well as the abscisic acid (ABA) content in roots. The relative expression of five drought-relative genes was also studied. The obtained results allowed examining the drought tolerance potential of ‘Garnem’ and Myrobalan ‘P.2175’, demonstrating the great potential of ‘Garnem’ as drought tolerance source in future selections in breeding. Furthermore, based on the obtained data, the transcription factor Myb25-like could be a good biomarker of drought sensitivity for use in Prunus rootstock breeding programs.

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Effect of PEG mediated water stress on solute accumulation, relative water content, biomass and antioxidant enzymes in rice

Indian Journal of Agricultural Research ◽

10.18805/ijare.v0iof.3759 ◽

2016 ◽

Author(s):

Ramadevi Kundur ◽

Papi Reddy Reddy T. ◽

Manohar Rao.T.

Keyword(s):

Antioxidant Enzymes ◽

Water Stress ◽

Drought Tolerance ◽

Water Content ◽

Relative Water Content ◽

Root Biomass ◽

Proline Accumulation ◽

Rice Varieties ◽

Breeding Programs ◽

Relative Water

In rice, several cultivated and upland varieties need to be assessed and analyzed for drought tolerance traits which could be used in screening and breeding programs for drought tolerance. Hence, the objectives of this study were to investigate the effects of water deficits in two rice cultivars and thereby analyze the role of several physiological traits useful in rice breeding programs for drought tolerance. The rice varieties Tellahamsa (TH) and N22 were screened for tolerance to drought. A comparative study was done subjecting them to PEG mediated water stress. Accumulation of solutes, i.e., proline, total free aminoacids and sugars; biomass production, Relative Water Content (RWC) and the levels of antioxidant enzymes, viz., Catalase (CAT), Ascorbate Peroxidase (APX), Glutathione Reductase(GR), and Superoxide Dismutase(SOD) were analyzed in response to water stress. Maximum proline accumulation was seen within 24hrs of stress, after 10 days TH decreased its proline to one-third, whereas in N22 doubled. Although amino acids doubled within 24hrs, gradually they depleted in N22. This may be due to conversion of aminoacids into proline which could be the most compatible solute. Sugars increased within 24hrs, but were depleted in 10days in both. In TH, the shoot and root biomass decreased, whereas in N22 there was a significant increase in root biomass. Shoot and root RWC of N22 was higher than TH under stress. GR increased in both TH and N22, APX and SOD increased only in N22. Proline accumulation, increase of root biomass and antioxidant enzymes such as APX or SOD during water stress are contributing to drought tolerance and could be used in screening for drought tolerance.

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The NAC-type transcription factor CaNAC46 regulates the salt and drought tolerance of transgenic Arabidopsis thaliana

BMC Plant Biology ◽

10.1186/s12870-020-02764-y ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Jing Ma ◽

Li-yue Wang ◽

Jia-xi Dai ◽

Ying Wang ◽

Duo Lin

Keyword(s):

Arabidopsis Thaliana ◽

Transcription Factor ◽

Transcription Factors ◽

Drought Tolerance ◽

Abiotic Stresses ◽

Lateral Roots ◽

High Salt ◽

Wild Type ◽

Ros Scavenging ◽

Drought And Salt Stresses

Abstract Background The NAC (NAM, ATAF1/ATAF2, and CUC2) transcription factors belong to a large family of plant-specific transcription factors in monocot and dicot species. These transcription factors regulate the expression of stress tolerance-related genes that protect plants from various abiotic stresses, including drought, salinity, and low temperatures. Results In this study, we identified the CaNAC46 transcription factor gene in Capsicum annuum. Its open reading frame was revealed to comprise 921 bp, encoding a protein consisting of 306 amino acids, with an isoelectric point of 6.96. A phylogenetic analysis indicated that CaNAC46 belongs to the ATAF subfamily. The expression of CaNAC46 was induced by heat, cold, high salt, drought, abscisic acid, salicylic acid, and methyl jasmonate treatments. Thus, CaNAC46 may be important for the resistance of dry pepper to abiotic stresses. A subcellular localization analysis confirmed that CaNAC46 is localized in the nucleus. The overexpression of CaNAC46 improved the tolerance of transgenic Arabidopsis thaliana plants to drought and salt stresses. The CaNAC46-overexpressing lines had longer roots and more lateral roots than wild-type lines under prolonged drought and high salt stress conditions. Additionally, CaNAC46 affected the accumulation of reactive oxygen species (ROS). Moreover, CaNAC46 promoted the expression of SOD, POD, RD29B, RD20, LDB18, ABI, IAA4, and P5CS. The malondialdehyde contents were higher in TRV2-CaNAC46 lines than in wild-type plants in response to drought and salt stresses. Furthermore, the expression levels of stress-responsive genes, such as ABA2, P5CS, DREB, RD22, CAT, and POD, were down-regulated in TRV2-CaNAC46 plants. Conclusions Under saline and drought conditions, CaNAC46 is a positive regulator that activates ROS-scavenging enzymes and enhances root formation. The results of our study indicate CaNAC46 is a transcriptional regulator responsible for salinity and drought tolerance and suggest the abiotic stress-related gene regulatory mechanisms controlling this NAC transcription factor are conserved between A. thaliana and pepper.

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Abscisic Acid Accumulation in Relation to Drought Tolerance in Kentucky Bluegrass

HortScience ◽

10.21273/hortsci.39.5.1133 ◽

2004 ◽

Vol 39 (5) ◽

pp. 1133-1137 ◽

Cited By ~ 14

Author(s):

Zhaolong Wang ◽

Bingru Huang ◽

Stacy A. Bonos ◽

William A. Meyer

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Electrolyte Leakage ◽

Poa Pratensis ◽

Net Photosynthesis ◽

Kentucky Bluegrass ◽

Drought Duration ◽

Turf Quality ◽

Relative Water ◽

Aba Content

Drought is a major factor limiting plant growth, which has been associated with the accumulation of absicsic acid (ABA) in various species. The objective of the study was to determine the relationship between ABA accumulation and drought tolerance for kentucky bluegrass (Poa pratensis L.) during short-term drought stress. Eight kentucky bluegrass cultivars (`Midnight', `A82-204', `RSP', `Alpine', `Moonlight', `Brilliant', `Washington', and `Baruzo') were subjected to drought stress in a growth chamber. Water relations, gas exchange rate, and ABA content of leaves were determined at various times during drought stress. Turf quality decreased with drought duration for all eight cultivars. Leaf ABA content increased linearly with drought stress within 11 days of treatment; the rate of the increase was negatively related to the rate of turf quality decline. The rate of ABA accumulation during drought stress was positively correlated with the rates of decrease in turf quality (r2 = 0.6346), increase in electrolyte leakage (r2 = 0.7128), and decrease in relative water content (r2 = 0.5913). There were highly significant negative correlations between ABA content and leaf water potential (r2 = 0.9074), stomatal conductance (r2 = 0.6088), transpiration rate (r2 = 0.6581), net photosynthesis rate (r2 = 0.6956), and a positive correlation between ABA content and electrolyte leakage (r2 = 0.7287). The results indicate that drought tolerance is negatively related to ABA accumulation during shortterm drought stress. ABA accumulation in response to drought stress could be used as a metabolic factor to select for drought tolerance in kentucky bluegrass.

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Overexpression of OsERF83, a Vascular Tissue-Specific Transcription Factor Gene, Confers Drought Tolerance in Rice

International Journal of Molecular Sciences ◽

10.3390/ijms22147656 ◽

2021 ◽

Vol 22 (14) ◽

pp. 7656

Author(s):

Se Eun Jung ◽

Seung Woon Bang ◽

Sung Hwan Kim ◽

Jun Sung Seo ◽

Ho-Bin Yoon ◽

...

Keyword(s):

Transcription Factor ◽

Transcription Factors ◽

Drought Tolerance ◽

Biotic Stress ◽

Abiotic Stresses ◽

Molecular Mechanisms ◽

Vascular Tissue ◽

Photochemical Efficiency ◽

Lignin Biosynthesis ◽

Pathogenesis Related Protein

Abiotic stresses severely affect plant growth and productivity. To cope with abiotic stresses, plants have evolved tolerance mechanisms that are tightly regulated by reprogramming transcription factors (TFs). APETALA2/ethylene-responsive factor (AP2/ERF) transcription factors are known to play an important role in various abiotic stresses. However, our understanding of the molecular mechanisms remains incomplete. In this study, we identified the role of OsERF83, a member of the AP2/ERF transcription factor family, in response to drought stress. OsERF83 is a transcription factor localized to the nucleus and induced in response to various abiotic stresses, such as drought and abscisic acid (ABA). Overexpression of OsERF83 in transgenic plants (OsERF83OX) significantly increased drought tolerance, with higher photochemical efficiency in rice. OsERF83OXwas also associated with growth retardation, with reduced grain yields under normal growth conditions. OsERF83 is predominantly expressed in the vascular tissue of all organs. Transcriptome analysis revealed that OsERF83 regulates drought response genes, which are related to the transporter (OsNPF8.10, OsNPF8.17, OsLH1), lignin biosynthesis (OsLAC17, OsLAC10, CAD8D), terpenoid synthesis (OsTPS33, OsTPS14, OsTPS3), cytochrome P450 family (Oscyp71Z4, CYP76M10), and abiotic stress-related genes (OsSAP, OsLEA14, PCC13-62). OsERF83 also up-regulates biotic stress-associated genes, including pathogenesis-related protein (PR), wall-associated kinase (WAK), cellulose synthase-like protein E1 (CslE1), and LysM receptor-like kinase (RLK) genes. Our results provide new insight into the multiple roles of OsERF83 in the cross-talk between abiotic and biotic stress signaling pathways.

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An R2R3-type myeloblastosis transcription factor MYB103 is involved in phosphorus remobilization

Food Production, Processing and Nutrition ◽

10.1186/s43014-020-00038-6 ◽

2020 ◽

Vol 2 (1) ◽

Author(s):

Fangwei Yu ◽

Shenyun Wang ◽

Wei Zhang ◽

Hong Wang ◽

Li Yu ◽

...

Keyword(s):

Cell Wall ◽

Transcription Factor ◽

Abiotic Stresses ◽

Myb Transcription Factor ◽

Ethylene Signaling ◽

Biotic And Abiotic Stresses ◽

P Deficiency ◽

P Concentration ◽

Increased Sensitivity

Abstract The members of myeloblastosis transcription factor (MYB TF) family are involved in the regulation of biotic and abiotic stresses in plants. However, the role of MYB TF in phosphorus remobilization remains largely unexplored. In the present study, we show that an R2R3 type MYB transcription factor, MYB103, is involved in phosphorus (P) remobilization. MYB103 was remarkably induced by P deficiency in cabbage (Brassica oleracea var. capitata L.). As cabbage lacks the proper mutant for elucidating the mechanism of MYB103 in P deficiency, another member of the crucifer family, Arabidopsis thaliana was chosen for further study. The transcript of its homologue AtMYB103 was also elevated in response to P deficiency in A. thaliana, while disruption of AtMYB103 (myb103) exhibited increased sensitivity to P deficiency, accompanied with decreased tissue biomass and soluble P concentration. Furthermore, AtMYB103 was involved in the P reutilization from cell wall, as less P was released from the cell wall in myb103 than in wildtype, coinciding with the reduction of ethylene production. Taken together, our results uncover an important role of MYB103 in the P remobilization, presumably through ethylene signaling.

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Adaptation assessment of drought tolerance in maize populations from the Sahara in both shores of the Mediterranean Sea

Euphytica ◽

10.1007/s10681-021-02902-z ◽

2021 ◽

Vol 217 (8) ◽

Author(s):

Oula Maafi ◽

Pedro Revilla ◽

Lorena Álvarez-Iglesias ◽

Rosa Ana Malvar ◽

Abderahmane Djemel

Keyword(s):

Drought Tolerance ◽

Biomass Production ◽

Genetic Regulation ◽

Breeding Programs ◽

Favorable Alleles ◽

Maize Germplasm ◽

Maize Populations ◽

Potential Source ◽

Main Stress ◽

And Control

AbstractDrought is the main stress for agriculture, and maize (Zea mays L.) germplasm from the Sahara has been identified as potential source of drought tolerance; however, information about adaptation of semitropical maize germplasm from the Sahara to temperate areas has not been reported. Our objective was assessing the adaptation of maize germplasm from Saharan oases as sources of drought tolerance for improving yield and biomass production under drought conditions in temperate environments. A collection of maize populations from Saharan oases was evaluated under drought and control conditions in Spain and Algeria. Algerian populations were significantly different under drought for most traits, and the significant genotype × environment interactions indicated that drought tolerance is genotype-dependent, but tolerance differences among genotypes change across environments. Based on yield, the Algerian maize populations PI527474, PI527478, PI527472, PI527467, PI527470, and PI527473 would be appropriate sources of drought tolerance for temperate environments. Concerning biomass production, the most interesting populations were PI527467, PI542685, PI527478, and PI527472. These Saharan populations could provide favorable alleles for drought tolerance for temperate breeding programs, and could also be used for studying mechanisms and genetic regulation of drought tolerance.

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EMS Derived Wheat Mutant BIG8-1 (Triticum aestivum L.)—A New Drought Tolerant Mutant Wheat Line

International Journal of Molecular Sciences ◽

10.3390/ijms22105314 ◽

2021 ◽

Vol 22 (10) ◽

pp. 5314

Author(s):

Marlon-Schylor L. le Roux ◽

Nicolas Francois V. Burger ◽

Maré Vlok ◽

Karl J. Kunert ◽

Christopher A. Cullis ◽

...

Keyword(s):

Amino Acids ◽

Water Deficit ◽

Triticum Aestivum L ◽

Water Deficit Stress ◽

Drought Response ◽

Fibrous Root ◽

Wheat Varieties ◽

Breeding Programs ◽

Response Characteristics ◽

Drought Tolerant

Drought response in wheat is considered a highly complex process, since it is a multigenic trait; nevertheless, breeding programs are continuously searching for new wheat varieties with characteristics for drought tolerance. In a previous study, we demonstrated the effectiveness of a mutant known as RYNO3936 that could survive 14 days without water. In this study, we reveal another mutant known as BIG8-1 that can endure severe water deficit stress (21 days without water) with superior drought response characteristics. Phenotypically, the mutant plants had broader leaves, including a densely packed fibrous root architecture that was not visible in the WT parent plants. During mild (day 7) drought stress, the mutant could maintain its relative water content, chlorophyll content, maximum quantum yield of PSII (Fv/Fm) and stomatal conductance, with no phenotypic symptoms such as wilting or senescence despite a decrease in soil moisture content. It was only during moderate (day 14) and severe (day 21) water deficit stress that a decline in those variables was evident. Furthermore, the mutant plants also displayed a unique preservation of metabolic activity, which was confirmed by assessing the accumulation of free amino acids and increase of antioxidative enzymes (peroxidases and glutathione S-transferase). Proteome reshuffling was also observed, allowing slow degradation of essential proteins such as RuBisCO during water deficit stress. The LC-MS/MS data revealed a high abundance of proteins involved in energy and photosynthesis under well-watered conditions, particularly Serpin-Z2A and Z2B, SGT1 and Calnexin-like protein. However, after 21 days of water stress, the mutants expressed ABC transporter permeases and xylanase inhibitor protein, which are involved in the transport of amino acids and protecting cells, respectively. This study characterizes a new mutant BIG8-1 with drought-tolerant characteristics suited for breeding programs.

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Spermine: Its Emerging Role in Regulating Drought Stress Responses in Plants

Cells ◽

10.3390/cells10020261 ◽

2021 ◽

Vol 10 (2) ◽

pp. 261

Author(s):

Md. Mahadi Hasan ◽

Milan Skalicky ◽

Mohammad Shah Jahan ◽

Md. Nazmul Hossain ◽

Zunaira Anwar ◽

...

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Stress Responses ◽

Abiotic Stresses ◽

Defense Mechanisms ◽

Antioxidant Defense ◽

Severe Drought ◽

New Information ◽

Effects Of Drought

In recent years, research on spermine (Spm) has turned up a lot of new information about this essential polyamine, especially as it is able to counteract damage from abiotic stresses. Spm has been shown to protect plants from a variety of environmental insults, but whether it can prevent the adverse effects of drought has not yet been reported. Drought stress increases endogenous Spm in plants and exogenous application of Spm improves the plants’ ability to tolerate drought stress. Spm’s role in enhancing antioxidant defense mechanisms, glyoxalase systems, methylglyoxal (MG) detoxification, and creating tolerance for drought-induced oxidative stress is well documented in plants. However, the influences of enzyme activity and osmoregulation on Spm biosynthesis and metabolism are variable. Spm interacts with other molecules like nitric oxide (NO) and phytohormones such as abscisic acid, salicylic acid, brassinosteroids, and ethylene, to coordinate the reactions necessary for developing drought tolerance. This review focuses on the role of Spm in plants under severe drought stress. We have proposed models to explain how Spm interacts with existing defense mechanisms in plants to improve drought tolerance.

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