Abstract
Extracts of the brown alga, Ascophyllum nodosum, are widely used as plant biostimulants to improve growth and to impart tolerance against abiotic stresses. However, the molecular mechanisms by which A. nodosum extract (ANE) mediates stress tolerance are still largely unknown. The aim of this study was to study selected anti-stress mechanisms at the transcriptome level. We show that methanolic sub-fractions of ANE improved growth of Arabidopsis thaliana under NaCl stress; biomass increased by approximately 50% under 100 mM and 150 mM NaCl, relative to the control. Bioassay-guided fractionation revealed that the ethyl acetate sub-fraction of ANE (EAA) had the majority of stress alleviating, bioactive components. Microarray analysis showed that EAA elicited substantial changes in the global transcriptome on day 1 and day 5, after treatment. On day one, 184 genes were up-regulated while this number increased to 257 genes on day 5. On the other hand, 91 and 262 genes were down-regulated on day 1 and day 5, respectively. On day 1, 2.2% of the genes altered were abiotic stress regulated and this increased to 6% on day 5. EAA modulate the expression of number of the genes involved in stress responses, carbohydrate metabolism, and phenylpropanoid metabolism. Thus, our results suggested that bioactive components in the ethyl acetate fraction of A. nodosum induced salinity tolerance in A. thaliana by modulating the expression of a plethora of stress-responsive genes, providing a better understanding of the mechanisms through which ANE mediates tolerance by plants to salinity stress.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Abercrombie JM, Matthew DH, Ranjan P, Rao MR, Saxton AM, Yuan JS, Stewart CN (2008) Transcriptional responses of Arabidopsis thaliana plants to As (V) stress. BMC Plant Biol 8(1):87
Agarwal PK, Jha B (2010) Transcription factors in plants and ABA dependent and independent abiotic stress signalling. Biol Plant 54:201–212. https://doi.org/10.1007/s10535-010-0038-7
Agarwal PK, Shukla PS, Gupta K, Jha B (2013) Bioengineering for salinity tolerance in plants: state of the art. Mol Biotechnol 54:102–123. https://doi.org/10.1007/s12033-012-9538-3
Agarwal PK, Gupta K, Lopato S, Agarwal P (2017) Dehydration responsive element binding transcription factors and their applications for the engineering of stress tolerance. J Exp Bot 68:2135–2148
Agati G, Azzarello E, Pollastri S, Tattini M (2012) Flavonoids as antioxidants in plants: location and functional significance. Plant Sci 196:67–76. https://doi.org/10.1016/j.plantsci.2012.07.014
Al-Maskri A, Al-Kharusi L, Al-Miqbali H (2010) Effects of salinity stress on growth of lettuce (Lactuca sativa) under closed-recycle nutrient film technique. Int J Agric Biol 12:377–380
Apse MP, Aharon GS, Snedden WA, Blumwald E (1999) Salt tolerance conferred by overexpression of a vacuolar Na+/H+ antiport in Arabidopsis. Science 285:1256–1258. https://doi.org/10.1126/science.285.5431.1256
Babu RC, Zhang J, Blum A, Ho THD, Wu R, Nguyen HT (2004) HVA1, a LEA gene from barley confers dehydration tolerance in transgenic rice (Oryza sativa L.) via cell membrane protection. Plant Sci 166:855–862. https://doi.org/10.1016/j.plantsci.2003.11.023
Bañuelos MA, Garciadeblas B, Cubero B, Rodríguez-Navarro A (2002) Inventory and functional characterization of the HAK potassium transporters of rice. Plant Physiol 130:784–795. https://doi.org/10.1104/pp.007781
Battacharyya D, Babgohari MZ, Rathor P, Prithiviraj B (2015) Seaweed extracts as biostimulants in horticulture. Sci Hortic 196:39–48. https://doi.org/10.1016/j.scienta.2015.09.012
Benjamini Y, Hochberg Y (1995) Controlling the false discovery rate: a practical and powerful approach to multiple testing. J R Stat Soc 57:289–300. https://doi.org/10.2307/2346101
Blunden G, Jenkins T, Liu YW (1997) Enhanced leaf chlorophyll levels in plants treated with seaweed extract. J Appl Phycol 8:535–543. https://doi.org/10.1007/BF02186333
Boudsocq M, Droillard MJ, Barbier-Brygoo H, Laurière C (2007) Different phosphorylation mechanisms are involved in the activation of sucrose non-fermenting 1 related protein kinases 2 by osmotic stresses and abscisic acid. Plant Mol Biol 63(4):491–503
Boyer JS (1982) Plant productivity and environment. Science 218:443–448. https://doi.org/10.1126/science.218.4571.443
Candat A, Paszkiewicz G, Neveu M, Gautier R, Logan DC, Avelange-Macherel MH, Macherel D (2014) The ubiquitous distribution of late embryogenesis abundant proteins across cell compartments in Arabidopsis offers tailored protection against abiotic stress. Plant Cell 26:3148–3166
Chandran D (2015) Co-option of developmentally regulated plant SWEET transporters for pathogen nutrition and abiotic stress tolerance. IUBMB Life 67(7):461–471
Chen CN, Chu CC, Zentella R, Pan SM, Ho THD (2002) AtHVA22 gene family in Arabidopsis: phylogenetic relationship, ABA and stress regulation, and tissue-specific expression. Plant Mol Biol 49:633–644
Chen JH, Jiang HW, Hsieh EJ, Chen HY, Chien CT, Hsieh HL, Lin TP (2012) Drought and salt stress tolerance of an Arabidopsis glutathione S-transferase U17 knockout mutant are attributed to the combined effect of glutathione and abscisic acid. Plant Physiol 158(1):340–351
Chinnusamy V, Jagendorf A, Zhu JK (2005) Understanding and improving salt tolerance in plants. Crop Sci 45:437. https://doi.org/10.2135/cropsci2005.0437
Christmann A, Moes D, Himmelbach A, Yang Y, Tang Y, Grill E (2006) Integration of abscisic acid signalling into plant responses. Plant Biol 8:314–325. https://doi.org/10.1055/s-2006-924120
Coello P, Hey SJ, Halford NG (2011) The sucrose non-fermenting-1-related (SnRK) family of protein kinases: potential for manipulation to improve stress tolerance and increase yield. J Exp Bot 62:883–893
Craigie JS (2011) Seaweed extract stimuli in plant science and agriculture. J Appl Phycol 23:371–393. https://doi.org/10.1007/s10811-010-9560-4
Delauney AJ, Verma DPS (1993) Proline biosynthesis and osmoregulation in plants. Plant J 4:215–223
Dong MA, Farré EM, Thomashow MF (2011) Circadian clock-associated 1 and late elongated hypocotyl regulate expression of the C-repeat binding factor (CBF) pathway in Arabidopsis. Proc Natl Acad Sci USA 108:7241–7246. https://doi.org/10.1073/pnas.1103741108
dos Reis SP, Lima AM, de Souza CRB (2012) Recent molecular advances on downstream plant responses to abiotic stress. Int J Mol Sci 13:8628–8647. https://doi.org/10.3390/ijms13078628
Elansary HO, Yessoufou K, Abdel-Hamid AM, El-Esawi MA, Ali HM, Elshikh MS (2017) Seaweed extracts enhance Salam turfgrass performance during prolonged irrigation intervals and saline shock. Front Plant Sci 8:830. https://doi.org/10.3389/fpls.2017.00830
Fahad S, Hussain S, Matloob A, Khan FA, Khaliq A, Saud S, Hassan S, Shan D, Khan F, Ullah N, Faiq M (2015) Phytohormones and plant responses to salinity stress: a review. Plant Growth Regul 75:391–404. https://doi.org/10.1007/s10725-014-0013-y
Fan D, Hodges DM, Zhang J, Kirby CW, Ji X, Locke SJ, Critchley AT, Prithiviraj B (2011) Commercial extract of the brown seaweed Ascophyllum nodosum enhances phenolic antioxidant content of spinach (Spinacia oleracea L.) which protects Caenorhabditis elegans against oxidative and thermal stress. Food Chem 124(1):195–202
Fan D, Hodges DM, Critchley AT, Prithiviraj B (2013) A commercial extract of brown macroalga (Ascophyllum nodosum) affects yield and the nutritional quality of spinach in vitro. Commun Soil Sci Plant Anal 44(12):1873–1884
Fini A, Brunetti C, Ferdinando MD, Ferrini F, Tattini M (2011) Stress-induced flavonoid biosynthesis and the antioxidant machinery of plants. Plant Signal Behav 6:709–711
Garg R, Shankar R, Thakkar B, Kudapa H, Krishnamurthy L, Mantri N, Varshney RK, Bhatia S, Jain M (2016) Transcriptome analyses reveal genotype-and developmental stage-specific molecular responses to drought and salinity stresses in chickpea. Sci Rep 6:9228
Goñi O, Fort A, Quille P, McKeown PC, Spillane C, O’Connell S (2016) Comparative transcriptome analysis of two Ascophyllum nodosum extract biostimulants: same seaweed but different. J Agric Food Chem 64(14):2980–2989. https://doi.org/10.1021/acs.jafc.6b00621
Goñi O, Quille P, O’Connell S (2018) Ascophyllum nodosum extract biostimulants and their role in enhancing tolerance to drought stress in tomato plants. Plant Physiol Biochem. https://doi.org/10.1016/j.plaphy.2018.02.024
Goyal K, Walton LJ, Tunnacliffe A (2005) LEA proteins prevent protein aggregation due to water stress. Biochem J 388:151–157. https://doi.org/10.1042/BJ20041931
Gupta AK, Kaur N (2005) Sugar signalling and gene expression in relation to carbohydrate metabolism under abiotic stresses in plants. J Biosci 30:761–776
He ZH, He D, Kohorn BD (1998) Requirement for the induced expression of a cell wall associated receptor kinase for survival during the pathogen response. Plant J 14:55–63. https://doi.org/10.1046/j.1365-313X.1998.00092.x
Hirayama T, Shinozaki K (2007) Perception and transduction of abscisic acid signals: keys to the function of the versatile plant hormone ABA. Trends Plant Sci 12(8):343–351
Hotta CT, Gardner MJ, Hubbard KE, Baek SJ, Dalchau N, Suhita D, Dodd AN, Webb AA (2007) Modulation of environmental responses of plants by circadian clocks. Plant Cell Environ 30:333–349
Hundertmark M, Hincha DK (2008) LEA (late embryogenesis abundant) proteins and their encoding genes in Arabidopsis thaliana. BMC Genom 9:118–139
Hwang SM, Kim DW, Woo MS, Jeong HS, Son YS, Akhter S, Choi GJ, Bahk JD (2014) Functional characterization of Arabidopsis HsfA6a as a heat-shock transcription factor under high salinity and dehydration conditions. Plant Cell Environ 37:1202–1222
Ishitani M, Majumder AL, Bornhouser A, Michalowski CB, Jensen RG, Bohnert HJ (1996) Coordinate transcriptional induction of myo-inositol metabolism during environmental stress. Plant J 9:537–548. https://doi.org/10.1046/j.1365-313X.1996.09040537.x
Jithesh MN, Wally OSD, Manfield I, Critchley AT, Hiltz D, Prithiviraj B (2012) Analysis of seaweed extract-induced transcriptome leads to identification of a negative regulator of salt tolerance in Arabidopsis. Hortic Sci 47:704–709
Khan W, Rayirath UP, Subramanian S, Jithesh MN, Rayorath P, Hodges DM et al (2009) Seaweed extracts as biostimulants of plant growth and development. J Plant Growth Regul 28:386–399. https://doi.org/10.1007/s00344-009-9103-x
Kumari M, Taylor GJ, Deyholos MK (2008) Transcriptomic responses to aluminum stress in roots of Arabidopsis thaliana. Mol Genet Genomics 279(4):339. https://doi.org/10.1007/s00438-007-0316-z
Kunkel BN, Brooks DM (2002) Cross talk between signaling pathways in pathogen defense. Curr Opin Plant Biol 5:325–331. https://doi.org/10.1016/S1369-5266(02)00275-3
Kyung JK, Yeon OK, Kang H (2005) Characterization of transgenic Arabidopsis plants overexpressing GR-RBP4 under high salinity, dehydration, or cold stress. J Exp Bot 56:3007–3016. https://doi.org/10.1093/jxb/eri298
Lai AG, Doherty CJ, Mueller-Roeber B, Kay SA, Schippers JH, Dijkwel PP (2012) CIRCADIAN CLOCK-ASSOCIATED 1 regulates ROS homeostasis and oxidative stress response. Proc Natl Acad Sci USA 109:17129–17134
Lang V, Palva ET (1992) The expression of a rab-related gene, rab18, is induced by abscisic acid during the cold acclimation process of Arabidopsis thaliana (L.) Heynh. Plant Mol Biol 20:951–962. https://doi.org/10.1007/BF00027165
Le Gall H, Philippe F, Domon JM, Gillet F, Pelloux J, Rayon C (2015) Cell wall metabolism in response to abiotic stress. Plants 4:112–166. https://doi.org/10.3390/plants4010112
Leyva-Gonzalez MA, Ibarra-Laclette E, Cruz-Ramirez A, Herrera-Estrella L (2012) Functional and transcriptome analysis 696 reveals an acclimatization strategy for abiotic stress tolerance mediated by Arabidopsis NF-YA family members. PLoS ONE 7:e48138
Livak KJ, Schmittgen TD (2001) Analysis of relative gene expression data using real-time quantitative PCR and the 2–∆∆CT method. Methods 25:402–408. https://doi.org/10.1006/meth.2001.1262
Lola-Luz T, Hennequart F, Gaffney M (2013) Enhancement of phenolic and flavonoid compounds in cabbage (Brassica oleraceae) following application of commercial seaweed extracts of the brown seaweed (Ascophyllum nodosum). Agric Food Sci 22(2):288–295
Loreti E, Povero G, Novi G, Solfanelli C, Alpi A, Perata P (2008) Gibberellins, jasmonate and abscisic acid modulate the sucrose-induced expression of anthocyanin biosynthetic genes in Arabidopsis. New Phytol 179:1004–1016
Mittler R, Vanderauwera S, Gollery M, Van Breusegem F (2004) Reactive oxygen gene network of plants. Trends Plant Sci 9:490–498. https://doi.org/10.1016/j.tplants.2004.08.009
Murashige T, Skoog F (1962) A revised medium for rapid growth and bio assays with tobacco tissue cultures. Physiol Plant 15:473–497. https://doi.org/10.1111/j.1399-3054.1962.tb08052.x
Nair P, Kandasamy S, Zhang J, Ji X, Kirby C, Benkel B et al (2012) Transcriptional and metabolomic analysis of Ascophyllum nodosum mediated freezing tolerance in Arabidopsis thaliana. BMC Genom 13:643. https://doi.org/10.1186/1471-2164-13-643
Negrão S, Schmöckel SM, Tester M (2017) Evaluating physiological responses of plants to salinity stress. Ann Bot 119(1):1–11. https://doi.org/10.1093/aob/mcw191
Oh SJ, Song SI, Kim YS, Jang HJ, Kim SY, Kim M et al (2005) Arabidopsis CBF3/DREB1A and ABF3 in transgenic rice increased tolerance to abiotic stress without stunting growth. Plant Physiol 138:341–351. https://doi.org/10.1104/pp.104.059147
Peng Z, Lu Q, Verma DP (1996) Reciprocal regulation of ∆ 1-pyrroline-5-carboxylate synthetase and proline dehydrogenase genes controls proline levels during and after osmotic stress in plants. Mol Genet Genomics 253:334–341
Rayirath P, Benkel B, Hodges DM, Allan-Wojtas P, MacKinnon S, Critchley AT et al (2009) Lipophilic components of the brown seaweed, Ascophyllum nodosum, enhance freezing tolerance in Arabidopsis thaliana. Planta 230:135–147. https://doi.org/10.1007/s00425-009-0920-8
Rayorath P, Jithesh MN, Farid A, Khan W, Palanisamy R, Hankins SD et al (2008) Rapid bioassays to evaluate the plant growth promoting activity of Ascophyllum nodosum (L.) Le Jol. using a model plant, Arabidopsis thaliana (L.) Heynh. J Appl Phycol 20:423–429. https://doi.org/10.1007/s10811-007-9280-6
Rengasamy KR, Kulkarni MG, Stirk WA, Van Staden J (2015) Eckol-a new plant growth stimulant from the brown seaweed Ecklonia maxima. J Appl Phycol 27:581–587
Reymond P, Weber H, Damond M, Farmer EE (2000) Differential gene expression in response to mechanical wounding and insect feeding in Arabidopsis. Plant Cell 12:707–720
Rosa M, Prado C, Podazza G, Interdonato R, González JA, Hilal M, Prado FE (2009) Soluble sugars: metabolism, sensing and abiotic stress: a complex network in the life of plants. Plant Signal Behav 4(5):388–393
Roxas VP, Lodhi SA, Garrett DK, Mahan JR, Allen RD (2000) Stress tolerance in transgenic tobacco seedlings that overexpress glutathione S-transferase/glutathione peroxidase. Plant Cell Physiol 41:1229–1234. https://doi.org/10.1093/pcp/pcd051
Schenk PM, Kazan K, Wilson I, Anderson JP, Richmond T, Somerville SC, Manners JM (2000) Coordinated plant defense responses in Arabidopsis revealed by microarray analysis. Proc Natl Acad Sci USA 97:11655–11660. https://doi.org/10.1073/pnas.97.21.11655
Seki M, Narusaka M, Ishida J, Nanjo T, Fujita M, Oono Y, Kamiya A, Nakajima M, Enju A, Sakurai T, Satou M (2002) Monitoring the expression profiles of 7000 Arabidopsis genes under drought, cold and high-salinity stresses using a full-length cDNA microarray. Plant J 31(3):279–292. https://doi.org/10.1046/j.1365-313X.2002.01359.x
Seo HS, Song JT, Cheong JJ, Lee YH, Lee YW, Hwang I et al (2001) Jasmonic acid carboxyl methyltransferase: a key enzyme for jasmonate-regulated plant responses. Proc Natl Acad Sci USA 98:4788–4793. https://doi.org/10.1073/pnas.081557298
Seo PJ, Park JM, Kang SK, Kim SG, Park CM (2011) An Arabidopsis senescence-associated protein SAG29 regulates cell viability under high salinity. Planta 233:189–200
Shi H, Ishitani M, Kim C, Zhu JK (2000) The Arabidopsis thaliana salt tolerance gene SOS1 encodes a putative Na+/H+ antiporter. Proc Natl Acad Sci USA 97:6896–6901. https://doi.org/10.1073/pnas.120170197
Shinozaki K, Yamaguchi-Shinozaki K (2000) Molecular responses to dehydration and low temperature: differences and cross-talk between two stress signaling pathways. Curr Opin Plant Biol 3:217–223
Shukla PS, Shotton K, Norman E, Neily W, Critchley AT, Prithiviraj B (2018) Seaweed extract improve drought tolerance of soybean by regulating stress-response genes. AoB Plants. https://doi.org/10.1093/aobpla/plx051
Subramanian S, Sangha JS, Gray BA, Singh RP, Hiltz D, Critchley AT et al (2011) Extracts of the marine brown macroalga, Ascophyllum nodosum, induce jasmonic acid dependent systemic resistance in Arabidopsis thaliana. against Pseudomonas syringae pv. tomato DC3000 and Sclerotinia sclerotiorum. Eur J Plant Pathol 131:237–248. https://doi.org/10.1007/s10658-011-9802-6
Swidzinski JA, Sweetlove LJ, Leaver CJ (2002) A custom microarray analysis of gene expression during programmed cell death in Arabidopsis thaliana. Plant J 30(4):431–446. https://doi.org/10.1046/j.1365-313X.2002.01301.x
Szabolcs I (1994) Soils and salinisation. In: Pessarakali M (ed) Handbook of plant and crop stress. Marcel Dekker, New York, pp 3–11
Taji T, Seki M, Satou M, Sakurai T, Kobayashi M, Ishiyama K et al (2004) Comparative genomics in salt tolerance between Arabidopsis and Arabidopsis-related halophyte salt cress using Arabidopsis microarray. Plant Physiol 135:1697–1709. https://doi.org/10.1104/pp.104.039909
Thalmann M, Santelia D (2017) Starch as a determinant of plant fitness under abiotic stress. New Phytol 214:943–951
Urano K, Maruyama K, Ogata Y, Morishita Y, Takeda M, Sakurai N, Suzuki H, Saito K, Shibata D, Kobayashi M, Yamaguchi-Shinozaki K (2009) Characterization of the ABA-regulated global responses to dehydration in Arabidopsis by metabolomics. Plant J 57(6):1065–1078
Valliyodan B, Nguyen HT (2006) Understanding regulatory networks and engineering for enhanced drought tolerance in plants. Curr Opin Plant Biol 9(2):189–195
Van Oosten MJ, Pepe O, De Pascale S, Silletti S, Maggio A (2017) The role of biostimulants and bioeffectors as alleviators of abiotic stress in crop plants. Chem Biol Technol Agric 4:5. https://doi.org/10.1186/s40538-017-0089-5
Verslues PE, Agarwal M, Katiyar-Agarwal S, Zhu J, Zhu JK (2006) Methods and concepts in quantifying resistance to drought, salt and freezing, abiotic stresses that affect plant water status. Plant J 45:523–539. https://doi.org/10.1111/j.1365-313X.2005.02593.x
Wally OSD, Critchley AT, Hiltz D, Craigie JS, Han X, Zaharia LI et al (2013) Regulation of phytohormone biosynthesis and accumulation in Arabidopsis following treatment with commercial extract from the marine macroalga Ascophyllum nodosum. J Plant Growth Regul 32:324–339. https://doi.org/10.1007/s00344-012-9301-9
Wang X (2005) Regulatory functions of phospholipase D and phosphatidic acid in plant growth, development, and stress responses. Plant Physiol 139(2):566–573
Wise MJ, Tunnacliffe A (2004) POPP the question: what do LEA proteins do? Trends Plant Sci 9:13–17. https://doi.org/10.1016/j.tplants.2003.10.012
Wright GW, Simon RM (2003) A random variance model for detection of differential gene expression in small microarray experiments. Bioinformatics 19:2448–2455. https://doi.org/10.1093/bioinformatics/btg345
Yadav NS, Shukla PS, Jha A, Agarwal PK, Jha B (2012) The SbSOS1 gene from the extreme halophyte Salicornia brachiata enhances Na+ loading in xylem and confers salt tolerance in transgenic tobacco. BMC Plant Biol 12:188. https://doi.org/10.1186/1471-2229-12-188
Yamaguchi-shinozakiaib K, Shinozaki K (1994) A nove1 cis-acting element in an Arabidopsis genes involved in responsiveness to drought, low temperature, or high-salt stress. Plant Cell 6:251–264. https://doi.org/10.1105/tpc.6.2.251
Zhang X, Ervin EH (2004) Cytokinin-containing seaweed and humic acid extracts associated with creeping bentgrass leaf cytokinins and drought resistance. Crop Sci 44:1737–1745. https://doi.org/10.2135/cropsci2004.1737
Zhang X, Schmidt RE (1999) Antioxidant response to hormone-containing product in Kentucky bluegrass subjected to drought. Crop Sci 39:545–551
Zhu JK (2003) Regulation of ion homeostasis under salt stress. Curr Opin Plant Biol 6:441–445. https://doi.org/10.1016/S1369-5266(03)00085-2
Acknowledgements
Authors are grateful for the valuable suggestions of Dr. Dhirti Battacharya and Emily Mantin for reading the manuscript. The work reported in this paper was partly funded by Atlantic Innovation Fund program of Atlantic Canada Opportunities Agency and Acadian Seaplants Limited.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of interest
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be considered as a potential conflict of interest. Authors declare no conflict of interest, financial or non-financial.
Electronic supplementary material
Below is the link to the electronic supplementary material.
Fig. S1
Methanolic extract of A. nodosum (MEA) impart protection against salinity stress. Two-week-old Arabidopsis were subjected to two different concentrations 100 and 150 mM NaCl. (A) Leaf Area (sq cm), (B) Plant Height (cm), (C) Leaf Number and (D) Fresh weight (mg). Fig. S2 Growth parameters of A. thaliana in the presence of salinity supplemented with different organic sub-fraction of A. nodosum (ANE): (A) Plant Height (cm) (B) Fresh weight (mg) (C) Leaf Number and (D) Leaf Area (sq cm) of Arabidopsis. Experiments without the NaCl treatments and quantification performed with or without the different sub-fraction treatment served as a control. Fig. S3 Relative root growth of Arabidopsis with different concentrations of EAA under salt stress. Relative root length of Arabidopsis upon treatment with different concentrations of EAA (0.1, 0.25, 0.5, 1.0 g L-1 equivalents of seaweed extract). The average root length (from 30 seedlings) was measured after 3 days of transferring to ½ MS plates supplemented with different concentrations of EAA under NaCl stress (100mM). Fig. S4 Salt stress sensitivity of wild-type (Col-0), sos mutants grown on vertical plates. Four-day-old seedlings of WT, cat2hp1, cat2hp2, sos1, sos2, sos3 were transferred from MS medium (1/2 x) to MS media containing 0 mM NaCl (A), 75 mM NaCl (B) or 75 mM NaCl supplemented with EAA (C). Seedlings were allowed to grow for 5 d. Fig. S5 Comparison of level of gene expression between EAA (A, B) and MEA (C, D) treatments. The relation between the 1.5-fold difference and statistical significance using t test are presented by volcano plots in EAA and MEA treatments at day 1 and day 5 post treatments. Fig. S6 Heat map representing the clustering of differentially expressed genes on day1 and day 5 of the application of EAA in the presence of 150 mM NaCl. The fold change expression data represented in this figure is obtained from three replicates. Color scale represents the normalized fold induction is presented in the figure: green represents high expression and red represents low expression. Fig. S7 Heat map representing the clustering of differentially expressed genes on day1 and day 5 of the application of MEA in the presence of 150 mM NaCl. The fold change expression data represented in this figure is obtained from three replicates. Color scale represents the normalized fold induction is presented in the figure: green represents high expression and red represents low expression. Fig. S8 MIPS classification of genes regulated by EAA treatments. Functional Classification (FunCat) of genes performed based on MIPS (http://bbc.botany.utoronto.ca/ntools/cgi-in/ntools_classification_superviewer.cgi) was used to analyze the GO categories of differentially regulated genes increased by EAA (A, B) and decreased by the treatment (C, D) over two days (day 1 and day 5). Figure shows the results of normalizing the frequency for the number of gene in each category to the frequency of the number of genes in each category present on the ATH1 gene chip. IDs falling into classification categories other than unclassified and classification not yet clear-cut were removed from these categories. (PDF 332 KB)
Rights and permissions
About this article
Cite this article
Jithesh, M.N., Shukla, P.S., Kant, P. et al. Physiological and Transcriptomics Analyses Reveal that Ascophyllum nodosum Extracts Induce Salinity Tolerance in Arabidopsis by Regulating the Expression of Stress Responsive Genes. J Plant Growth Regul 38, 463–478 (2019). https://doi.org/10.1007/s00344-018-9861-4
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00344-018-9861-4