The Possibility of Inducing Resistance in Tomato against Rhizoctonia solani and some of its Mechanisms

Document Type : Research Article

Authors

• F. Nikraftar
• P. Taheri
• S. Tarighi

Ferdowsi University of Mashhad

10.22067/jpp.v30i3.44805

Abstract

Introduction: Tomato (Solanum lycopersicum) is one of the most important crops worldwide, which suffers from several destructive diseases. Rhizoctonia solani is a necrotrophic fungus which is known as the causal agent of tomato damping-off, seed rot, root and crown rot diseases. Control of this phytopathogenic fungus is very difficult due to its long-term survival in the soil, high level of genetic diversity in R. solani populations and the lake of complete resistance in plants to the pathogen. Although partial genetic resistance to Rhizoctonia diseases has been reported, no major gene responsible for resistance has been found so far. Most of the traditional cultivars, planted in tomato-growing areas, are susceptible to Rhizoctonia diseases. Therefore, an intensive use of other crop protection methods such as an application of chemicals or biological agent which are capable of activating plant defense responses seems to be necessary to suppress the disease damage in tomato fields. The growing concern on negative environmental effects of fungicides and the appearance of fungicide- resistant pathogens led to increased research interest in the alternative protection methods. Among these novel disease management strategies, induced resistance (IR) has emerged as a potential supplement in plant protection trials.
Materials and Methods: The cultivar CH Falat was used as a susceptible tomato genotype to R. solani. The seeds were surface sterilized with 1% sodium hypochlorite for 1min, rinsed 3 times with sterile distilled water and incubated for 5 days on a wet sterile filter paper in Petri dishes. Germinated seeds were each sown in plastic pots filled with autoclaved commercial potting soil and kept in greenhouse conditions. The tomato leaves were treated with various concentrations of thiamine, pyridoxine, and homoserine lactones and inoculated with the pathogen. Disease symptoms were evaluated at 5 days post-inoculation (dpi) and the most effective inducer of resistance at the best concentration was selected for the rest of the experiments. The role of phenolic compounds and peroxidase in thiamine-IR was investigated in our pathosystem. For phenolics measurement, leaf and stem samples (500 mg FW) were crushed into fine powder in liquid N2 with a mortar and pestle and were extracted separately in 8 ml of 80% methanol. The extracts were centrifuged at 4000 g for 5 min. To determine the number of total phenols, 50 ml of the extract was placed in microtubes containing 700 ml of distilled water and 50 ml of Folin. After 5 min, 100 ml of 20% sodium carbonate and 100 ml distilled water were added and the tube contents were mixed. Absorbance at 720 nm was determined after 60 min using a spectrophotometer. Total phenol was expressed as the milligrams per gram of tissue fresh weight. Soluble phenolic contents were calculated using a standard curve obtained with different concentrations of caffeic acid. For determining peroxidase activity, enzyme extracts (containing 30 mg of total protein) were added to 30 ml of 200 mM guaiacol and 25mM citrate phosphate (pH 5.4). To each sample, 30 ml of 30% H2O2 was added and the absorbance was measured at 470 nm using a spectrophotometer.
Results and Discussion: Disease index evaluations after various treatments revealed that thiamine 20 mM had the best effect in inducing resistance to the pathogen. This vitamin was used for treating the tomato leaves in subsequent experiments. For investigation of the role of peroxidase in thiamine- induced resistance, NaN3 was used as a specific peroxidase inhibitor and phenolic contents were measured in infected samples treated with thiamine and NaN3 at 0, 24, 48 and 72 hours after inoculation. There was a considerable difference between the phenolics level in different samples at various time points investigated in this study. The phenolics level in the samples treated with NaN3 was lower than other treatments. As a result, considering the role of peroxidase in phenolics production, the inhabitation of peroxidase activity leads to a reduction of phenolics and decrease of resistance to the pathogen in the tomato leaves treated with thiamine together with NaN3.
Conclusion: The results obtained in this study revealed the great potential of thiamine, as an environmentally safe vitamin, for induction of defense responses and partial protection of tomato plants against the destructive necrotrophic fungus R. solani AG4 HG I. It can be concluded that peroxidase and phenolics have an important role in thiamine-IR in tomato- R. solani interaction.

Keywords

• Induced resistance
• Peroxidase
• Solanum lycopersicum
• Total phenol
• Vitamin B1

20.1001.1.20084749.1395.30.3.9.3

---

References

1- Abdel- Monaim M.F. 2011. Role of riboflavin and thiamine in induced resistance against charcoal rot disease of soybean. African Journal of Biotechnology , 10: 10842-10855.

2- Ahn I. P., Kim S., and Lee Y.H. 2005. Vitamin B1 functions as an activator of plant disease resistance. Journal of Plant Physiology, 138:1505-1515.

3- Ahn I.P., Kim S., Lee, W.H., and Suh S.C. 2007. Vitamin B1-induced priming is dependent on hydrogen peroxide and the NPR1 gene in Arabidopsis. Journal of Plant Physiology, 143: 838–848.

4- Bahuguna R.N., Joshi R., Shukla A., Pandey M., and Kumar J. 2012. Thiamine primed defense provides reliable alternative to systemic fungicide carbendazim against sheath blight disease in rice (Oryza sativa L.). Plant Physiology and Biochemistry, 57: 159-167.

5- Blokhina O.B., Chirkova T.V., and Fagerstedt K.V. 2001. Anoxic stress leads to hydrogen peroxide formation in plant cells. Journal of Experimental Botany, 52, 1179–90

6- Boubakri H., Wahab M.A., Chong J., Bertsch C., Mliki A., and Gacougnolle I.S. 2012. Thiamine induced resistance to Plasmopara viticola in grapevine and elicited host defense responses, including HR like-cell death. Plant Physiology and Biochemistry, 57: 120-13.

7- Denslow Sh.A., Rueschhoff E.E., and Daub M.E. 2007. Regulation of the Arabidopsis thaliana vitamin B6 biosynthesis genes by abiotic stress. Plant Physiology and Biochemistry, 45: 152-161.

8- Djebali N., Mhadhbi H., Lafitte C., Dumas B., Esquerre-Tugaye M. T., Aouani M. E., and Jacquet C. 2011. Hydrogen peroxide scavenging mechanisms are componentsof Medicago truncatula partial resistanceto Aphanomyces euteiches. European Journal of Plant Pathology, 131: 559-571.

9- Gonzalez G., Portal Onco M.A., and Rubio SusanV. 2006. Biology and systematic of form genus Rhizoctonia. Spanish Journal of Agricultural Research, 4: 55-79.

10- Goyer A. 2010. Thiamine in plants: aspects of its metabolism and functions, Phytochemistry, 17: 1615–1624.

11- Harrison S., Curtis M., McIntyre C., Maclean D., and Manners J. 1995. Differential expression of peroxidase isogenes during the early stages of infection of the tropical forage legume Stylosanthes humilis by Colletotrichum gloeosporioides. Molecular Plant-Microbe Interaction, 8: 398-406.

12- Hung K.T., and Kao C.H. 2004. Hydrogen peroxide is necessary for abscisic acid-induced senescence of rice leaves. Journal of Plant Physiology, 161: 1347-1357.

13- Hilaire E., Young S.A., Willard L.H., McGee J.D., Sweat T., Chittoor J.M., Guikema J.A., and Leach J.E. 2001. Vascular defense responses in rice: Peroxidase accumulation in xylem parenchyma cells and xylem wall thickening. Molecular Plant-Microbe Interaction. 14: 1411-1419.

14- Jung W.J., Mabood F., Kim T.H., and Smith D.L. 2007. Induction of pathogenesis-related proteins during biocontrol of Rhizoctonia solani with Pseudomonas aureofaciens in soybean (Glycine max L. Merr.) plants. BioControl, 52: 895–904.

15- Kuramae E.E., Buzeto A.L., Ciampi M.B., and Souza N.L. 2003. Identification of Rhizoctonia solani AG 1-IB in lettuce, AG 4 HG-I in tomato and melon, and AG 4 HG-III in broccoli and spinach, in Brazil. European Journal of Plant Pathology, 109: 391–395.

16- Luzzatto T., Golan A., Yishay M., Bilkis I., Ben-Ari J., and Yedidia I. 2007. Priming of antimicrobial phenolics during induced resistance response towards Pectobacterium carotovorumin the ornamenta lmonocot calla lily. Journal Agricultural and Food Chemistry, 55: 10315–10322.

17- Matern U., and Kneusal R.E. 1998. Phenolic compounds in plant disease resistance. Phytoparasitica, 16: 153–170.

18- Nikraftar F., Taheri P., Flahati-Rastgar M., and Tarighi S. 2013. Tomato partial resistance to Rhizoctonia solani involves antioxidative defense mechanisms. Physiological and Molecular Plant Pathology 81:74–83.

19- Oñate-Sanchez L., and Vicente-Carbajosa J. 2008. DNA-free RNA isolation protocols for Arabidopsis thaliana, including seeds and siliques. BMC Research Notes, 1: 1-7.

20- Pushpalatha H.G., Mythrashree S.R., Shetty R., Geetha N.P., Sharathchandra R.G., Amruthesh K.N., and Shetty H.S. 2007. Ability of vitamins to induce downy mildew disease resistance and growth promotion in pearl millet. Crop Protection, 26: 1674–1681.

21- Pushpalatha H.G., Sudisha J., Geetha N.P., Amruthesh K.N., and Shekar Shetty H. 2011. Thiamine seed treatment enhances LOX expression, promotes growth and induces downy mildew disease resistance in pearl millet. Biologia Plantarum, 55: 522-527.

22- Rai G.K., Kumar R., Singh J., Rai P.K., and Rai S.K. 2011. Peroxidase, polyphenol oxidase activity, protein profile and phenolic content in tomato cultivars tolerant and susceptible to Fusarium oxsyporum f.sp. lycopersici. Journal of Botany, 43: 2987-2990.

23- Rajasekaran K., Cary J.W., Jacks T.J., Stromberg K.D., and Cleveland T.E. 2000. Inhibition of fungal growth in planta and in vitro by transgenic tobacco expressing a bacterial nonheme chloroperoxidase gene. Plant Cell Reports, 19:333–338

24- Sadrovi M., and Setayeshmehr F. 2008. Fungal diseases of tomato in North Khorasan province and the reaction of four commercial cultivars to their Pathogens. Journal of plant diseases,44: 255- 261. (in Persian)

25- Schikora A., Schenk S.T., Stein E., Molitor A., Zuccaro A., and Kogel K.H. 2011. N-Acyl-homoserine lactone confers resistance toward biotrophic and hemibiotrophic pathogens via altered activation of AtMPK6. Plant Physiology, 157: 1407–1418.

26- Schuhegger R., Ihring A., Gantner S., Bahnweg G., Knappe C.,Vogg G., Hutzler P., Schmid M., Breusegem F.N., Eberl L., Hartmann A., and Langebartels C. 2006. Induction of systemic resistance in tomato by N-acyl-L-homoserine lactone-producing rhizosphere bacteria. Plant, Cell and Environment, 29: 909–918.

27- Schwartz H.F., and Gent D.H. 2007. Homepage of high plains integrated pest management. Damping off and seedling blight. wiki.bugwood.org, Visited: 2007/01/04

28- Seevers P.M., Daly J.M., and Catedral F.F. 1971. The Role of Peroxidase Isozymes in Resistance to Wheat Stem Rust Disease. Journal of Plant physiology, 48: 353-360.

29- Shahbazi H., Aminian H., Sahebani N., and Halterman D. A. 2010. Biochemical Evaluation of Resistance Responses of Potato to Different Isolates of Alternaria solani. Phytopathalogy, 100: 454-459.

30- Sneh B., Burpp L., and Ogoshi A. 1991. Identification of Rhizoctonia species. APS Press, 133 Pp.

31- Taheri P., Gnanamanickam S., and Hofte M. 2007. Characterization, genetic structure, and pathogenicity of Rhizoctonia spp. associated with rice sheath diseases. Phytopathology, 97: 373–83.

32- Taheri P., and Tarighi S. 2009. A study on the effect of riboflavin as a defense activator in rice against Rhizoctonia diseases. Journal of Plant Protection, 23: 68- 80.(in Persian)

33- Taheri P., and Tarighi S. 2010. Riboflavin induces resistance in rice against Rhizoctonia solani via jasmonate-mediated priming of phenylpropanoid pathway. Journal of Plant Physiology, 167: 201–208.

34- Taheri P., and Tarighi S. 2011. A survey on basal resistance and riboflavin-induced defense responses of sugar beet against Rhizoctonia solani. Journal of Plant Physiology, 168: 1114–1122.

35- Taheri P., and Tarighi S. 2012. The Role of Pathogenesis-Related Proteins in Tomato-Rhizoctonia solani Interaction. Journal of Botany, 2012. http://dx.doi.org/10.1155/2012/37037.