Effect of Plant Growth Promoting Bacteria on Growth and Biochemical Indices of Lettuce under Powdery Mildew Biotic Stress

Document Type : Research Article

Authors

• Parastoo Molaei ¹
• Fatemeh Nekounam ²

¹ Department of Horticulture, Faculty of Agriculture, University of Zanjan, Zanjan, Iran

² Department of Horticultural Science, Faculty of Agriculture, University of Zanjan, Zanjan, Iran

https://doi.org/10.22067/jhs.2022.79038.1198

Abstract

Introduction
Lettuce (Lactuca sativa L.) from the Asteraceae family is one of the most important vegetables due to its rapid growth and commercial value. Currently, the market share of organic vegetables is constantly increasing due to customer demand for safer and healthier food. Excessive use of pesticides and chemical fertilizers threatens the environment and leads to the production of unsafe food products. Therefore, it is important to find alternatives instead of using pesticides chemical methods to manage powdery mildew. Generally, biotic and abiotic stresses are among the factors that have a destructive effect on growth and development, performance, and production of plant biomass. Fungicides can be the most effective method of controlling the powdery mildew disease, but this pathogen can develop resistance to fungicides. Rhizosphere bacteria are among the living agents that, by producing some allelochemicals, cause the dissolution of soil nutrients, increase the availability of nutrients, and induce plant resistance to biotic and abiotic stresses. In addition, they enhance host plant growth through an indirect mechanism, including the inhibition of disease-causing pathogens by releasing some allelochemical substances. The biological control of powdery mildew disease with the use of rhizospheric bacteria in lettuce and zucchini has been reported.
 
Material and Methods
To evaluate the biological control of powdery mildew fungus with plant growth promoting rhizobacteria (PGPR) and effects on yield and quality of New Red Fire greenhouse lettuce, an experiment was carried out in a completely randomized design with three replications in the Research greenhouse of University of Zanjan during 2020. Experiment treatments consisted of five levels of PGPR (Pseudomonas vancouverensis- VPM, Pseudomonas Koreensis- KPM, Pantoea agglomerans- PAPM, Pseudomonas putida- PPM, and one level of combined bacteria (Pantoea agglomerans+ Pseudomonas Koreensis+ Pseudomonas putida+ Pseudomonas vancouverensis- MBPM, one level of chemical fertilizer 100% N, P and, K according to soil test results- NPK, and two control treatment without powdery mildew condition (C) and under powdery mildew conditions (CPM).
The “New Red Fire” lettuce seeds were surface sterilized with 0.5% (v/v) sodium hypochlorite for 10 min and germinated at 20ºC. After germination, seedlings with similar size were transplanted into pots. Plants were grown under greenhouse condition with 60/70 % (day/night) relative humidity, 15/18 °C (day/night) temperature. Inoculation of pathogenic fungi was done 40 days after seed germination. Plants were harvested after 75 days. The chlorosis and necrosis spots number on each plant, plant fresh weight, plant dry weight, leaf number, total chlorophyll, total phenol and flavonoids contents, antioxidant activity, anthocyanin content, and catalase and peroxidase enzyme activity were measured.
 
Results
The results showed that the application of potassium and phosphorus solubilizing bacteria and NPK fertilizer significantly increased plant growth compared to control plants under the stress of powdery mildew fungus. The highest plant fresh weight, percentage of plant dry weight, and leaf number were obtained with the application of combined potassium and phosphorus solubilizing bacteria treatment and 100% N fertilizer under the biostress. The maximum total chlorophyll was obtained with the application of Pseudomonas koreensis and Pantoea agglomerans bacteria. 100% reduction of necrosis spots was obtained by using the Pantoea agglomerans bacteria. The maximum of chlorosis spots (increase of 55.8%) and necrosis spots (an increase of 88.8%), total phenol (an increase of 52%), total flavonoids (an increase of 39.3%), catalase (an increase of 28.4%) and peroxidase enzymes activity (49.1%) were obtained with application of NPK fertilizer. No significant effect on antioxidant activity was observed with the application of chemical fertilizer and rhizosphere bacteria under the Biostress. The maximum anthocyanin contents were obtained with the application of Pseudomonas koreensis.
 
Conclusion
According to the results, the application of NPK chemical fertilizer and seed pretreatment of lettuce with PGPR increased the value of antioxidant compounds including total phenol, flavonoid, and anthocyanin contents and catalase and peroxidase enzymes activity under powdery mildew conditions. Inoculation of lettuce seeds with PGPR, in addition to improve plant growth under biological stress conditions, increased anthocyanin contents and induced the resistance of lettuce plants to powdery mildew. Seed pretreatment with PGPR reduced chlorosis and necrosis spots in leaves. Therefore, pretreatment of lettuce seeds with PGPR instead of chemical compounds (fertilizers, pesticides and plant growth regulators) is recommended to improve the yield and quality of lettuce under powdery mildew conditions.

Keywords

• Anthocyanin
• Biological control
• Biostress
• Necrotic spots
• Powdery mildew

Main Subjects

• Growing vegetables

©2022 The author(s). This is an open access article distributed under Creative Commons Attribution 4.0 International License (CC BY 4.0), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source.

References

1- Ahemad, M., & Kibret, M. (2014). Mechanisms and application s of plant growth promoting rhizobacteri a: Current perspective. Journal of King Saud University Science, 26, 1-20. https://doi.org/10.1016/j.jksus.2013.05.001

2- Arnon, A.N. (1967). Method of extraction of chlorophyll in the plants. Agronomy Journal, 23, 112-121.

3- Babu, S., Prasanna, R., Bidyarani, N., Nain, L., & Shivay, Y.S. (2015). Synergistic action of PGP agents and Rhizobium spp. for improved plant growth, nutrient mobilization and yields in different leguminous crops. Biocatal Agric Biotechnol, 4, 456-464. https://doi.org/10.1016/j.bcab.2015.09.004

4- Bahrami, N., Jalali, M., & Zare, A.K. (2020). The effect of various sources of iron on the nitrate accumulation in lettuce (Lactuca sativa L.). Iranian Journal of Soil and Water Research, 51, 2953-2963. (In Persian with English abstract). https://doi.org/10.22059/ijswr.2020.306193.668669

5- Basu, S., Roychoudhury, A., Saha, P.P., & Sengupta, D.N. (2010). Differential antioxidative responses of indica rice cultivars to drought stress. Plant Growth Regulation, 60, 51-59. https://doi.org/10.1007/s10725-009-9418-4 

6- Cappellari, L.D.R., Santoro, M.V., Nievas, F., Giordano, W., & Banchio, E. (2013). Increase of secondary metabolite content in marigold by inoculation with plant growth-promoting rhizobacteria. Applied Soil Ecology, 70, 16-22. https://doi.org/10.1016/j.apsoil.2013.04.001

7- Cézard, C., Farvacques, N., & Sonnet, P. (2015). Chemistry and biology of pyoverdines, Pseudomonas primary siderophores. Current Medicinal Chemistry, 22, 165-186. https://doi.org/10.2174/0929867321666141011194624

8- Chang, C., Yang, M., Wen, H., & Chern, J. (2002). Estimation of total flavonoid content in propolis by two complementary colorimetric methods. Journal of Food and Drug Analysis, 10, 178-182. https://doi.org/10.38212/2224-6614.2748

9- Chen, Y., Cao, S., Chai, Y., Clardy, J., Kolter, R., Gue, J., & Losick, R. (2012). A Bacillus subtilis sensor kinase involved in triggering biofilm formation on the roots of tomato plants. Molecular Microbiology, 85, 418-430. https://doi.org/10.1111/j.1365-2958.2012.08109.x

10- Chithrashree, C., & Srinivas, C. (2012). Role of antioxidant scavenging enzymes and extracellular polysaccharide in pathogenicity of rice bacterial blight pathogen Xanthomonas oryzae pv. Oryzae. African Journal of Biotechnology, 11, 13186-13193. https://doi.org/10.5897/AJB12.1670

11- Demiray, S., Pintado, M.E., & Castro, P.M.L. (2009). Evaluation of phenolic profiles and antioxidant activities of Turkish medicinal plants: Tilia argentea, Crataegi folium leaves and Polygonum bistorta roots. World Academy of Science Engineering and Technology, 54, 312-317. https://doi.org/10.5281/zenodo.1075066

12- Derikvand, F., Bazgir, E., Darvishnia, M., & Mirzaei Najafgholi, H. (2020). A study on the changes of some enzymes related to antioxidant defense system in common bean against Xanthomonas axonopodis pv. Phaseoli. Nova Biologica Reperta, 6, 424-434. (In Persian with English abstract). https://doi.org/10.29252/nbr.6.4.424

13-Dinesh, R., Anandaraj, M., Kumar, A., Bini, Y.K., Subila, K.P., & Aravind, R. (2015). Isolation, characterization, and evaluation of multi-trait plant growth promoting rhizobacteria for their growth promoting and disease suppressing effects on ginger. Microbiological Research, 173, 34-43. https://doi.org/10.1016/j.micres.2015.01.014

14- Farahani, A.S., & Taghavi, M. (2016). Changes of antioxidant enzymes of mung bean [Vigna radiata (L.) R. Wilczek] in response to host and non -host bacterial pathogens. Journal of Plant Protection Research, 56, 95-99. https://doi.org/10.1515/jppr-2016-0016

15- Fernandez, O., Theocharis, A., Bordiec, S., Feil, R., Jacquens, L., & Clement, C. (2012). Burkholderia phytofirmans PsJN acclimates grapevine to cold by modulating carbohydrate metabolism. Molecular Plant-Microbe Interactions, 25, 496-504. https://doi.org/10.1094/MPMI-09-11-0245

16- Glick, B.R. (2012). Plant growth-promoting bacteria: mechanisms and applications. Hindawi Publishing Corporation Scientifica. https://doi.org/10.6064/2012/963401

17- Itako, A.T., Tolentino Júnior, J.B., Júnior, S., Soman, J.M., & Maringoni, A.C. (2015). Chemical products induce resistance to Xanthomonas perforans in tomato. Brazilian Journal of Microbiology, 46, 701-706. https://doi.org/10.1590/S1517-838246320140177

18- Jamali Zavareh, A.H., Sharifi Tehrani, A., Hejarood, GH.A., Zad, S.J., Mohammadi, M., & Talebi Jahromi, K.J. (2004). An investigation of the effectiveness of acibenzolar S methyl for the control of cucumber powdery mildew. Iranian Journal of Agriculture Science, 35, 2. (In Persian with English abstract)

19- Jayaprakashvel, M., & Mathivanan, N. (2011). Management of plant diseases by microbial metabolites. In, Maheshwari DK (ed) Bacteria in agrobiology, plant nutrient management. Springer Berlin Heidelberg, 237-265.

20- Kara, M., & Mishra, E. (1976). Catalse, peroxidase and polyphenol oxidase activities rice leaf senescence. Plant Physiology, 57, 315-319. https://doi.org/10.1104/pp.57.2.315

21- Koc, E., İslek, C., & Üstun, A.S. (2010). Effect of cold on protein, proline, phenolic compounds and chlorophyll content of two pepper (Capsicum annuum L.) varieties. Gazi University Journal of Science, 23, 1-6.

22- Kumar, M., Mishra, S., Dixit, V., Kumar, M., Agarwal, L., Singh Chauhan, P., & Shekhar Nautiyal, C. (2015). Synergistic effect of Pseudomonas putida and Bacillus amyloliquefaciens ameliorates drought stress in chickpea (Cicer arietinum L.). Plant Signaling and Behavior, 11, e1071004. https://doi.org/10.1080/15592324.2015.1071004

23- Lindenthal, M., Steiner, U., Dehne, H.W., & Oerke, E.C. (2005). Effect of downy mildew development on transpiration of cucumber leaves visualized by digital infrared thermography. Phytopathology, 95, 233-240. https://doi.org/10.1094/PHYTO-95-0233

24- Liu, F., Zhuge, Y.Y., Yang, C.Y., Jin, S.X., Chen, J., Li, H., & Dai, G.H. (2010). Control effects of some plant extracts against cucumber powdery mildew (Sphaerotheca fuliginea) and their Stability Study. Europ, Journal of Horticultural Science, 75, 147-152. https://doi.org/10.2307/24127045

25- Mahfouz, S.A., & Sharaf- Eldin, A. (2007). Effect of mineral vs. biofertilizer on growth, yield and essential oil content of fennel (Foeniculum vulgare Mill.). International Agrophysics, 2, 361-366. https://doi.org/10.1055/s-2007-987419

26- Mampholo, B.M., Maboko, M.M., Soundy, P., & Sivakumar, D. (2016). Phytochemicals and overall quality of leafy lettuce (Lactuca sativa L.) varieties grown in closed hydroponic system. Journal of Food Quality, 39, 805-815. https://doi.org/10.1111/jfq.12234

27- Martins, S.J., Medeiros, F.H.V., Souza, R.M., & Resende, M.L.V. (2013). Biological control of bacterial wilt of common bean by plant growth-promoting rhizobacteria. Biological Control, 66, 65-71. https://doi.org/10.1016/j.biocontrol.2013.03.009

28- McGrath, M.T. (2017). Vegetable crops: powdery mildew of Cucurbits, Cooperative extension. https://vegetablemdonline.ppath.cornell.edu/fact sheets/Cucurbits_PM.htm

29- Miliauskas, G., Venskutonis, P.R., & Vanbeek, T.A. (2004). Screening of radical scavenging activity of some medicinal and aromatic plant extracts. Food Chemistry, 85, 231-237. https://doi.org/10.1016/j.foodchem.2003.05.007

30- Molaei, P., Barzegar, T., Baba Akbari Sari, M., Nekounam, F., & Ghahremani, Z. (2023). The effect of bio and chemical fertilizers on yield and quality of lettuce (Lactuca sativa cv. New Red Fire). Journal of Horticultural Science, 37(3), 685-697. (In Persian with English abstract). https://doi.org/10.22067/jhs.2022.76893.1175

31- Narendra Babu, A., Jogaiah, S., Ito, S., Kestur Nagaraj, A., & Tran, L.S.P. (2015). Improvement of growth, fruit weight and early blight disease protection of tomato plants by rhizosphere bacteria is correlated with their beneficial traits and induced biosynthesis of antioxidant peroxidase and polyphenol oxidase. Journal of Plant Sciences, 231, 62-73. https://doi.org/10.1016/j.plantsci.2014.11.006

32- Radhakrishnan, R., Hashem, A., & Abd-Allah, E.F. (2017). Bacillus: a biological tool for crop improvement through bio- molecular changes in adverse environments. Frontiers in Physiology, 8, 667. https://doi.org/10.3389/fphys.2017.00667

33- Saharan, B.S., & Nehra, V. (2011). Plant growth promoting rhizobacteria. Life Sciences and Medicine Research, 21, 1-30.

34- Saraf, M., Pandya, U., & Thakkar, A. (2014). Role of allelochemicals in plant growth promoting rhizobacteria for biocontrol of phytopathogens. Microbiological Research, 169, 18-29. https://doi.org/10.1016/j.micres.2013.08.009

35- Shariatifar, N., Kamakar, A., Shams Ardakani, M.R., Misaghi, A., Jamshidi, A.H., & Khaniki, J. (2012). Quantitative and qualitative study of phenilic compounds and antioxidant activity of plant pulicaria gnaphalodes. Journal of Gonabad University of Medical Sciences, 18, 35-42. (In Persian with English abstract)

36- Singla, J., & Krattinger, S.G. (2016). Biotic stress resistance genes in wheat. In: Wrigley, C.W., Faubion, J., Corke, H., Seetharaman, K. (Eds.). Encyclopedia of Food Grains Elsevier Oxford, 388-392. https://doi.org/10.1016/B978-0-12-394437-5.00229-1

37- Singleton, V.L., & Rossi J.A. (1965). Colorimetry of total phenolics with phosphomolybdic-phosphotungstic acid reagents. American journal of Enology and Viticulture, 16(3), 144-158.‏ https://doi.org/10.5344/ajev.1965.16.3.144

38- Sirous, A., & Jamali Zavareh, A.H. (2014). Effectiveness of celery leaf extract on the induction of resistance against cucumber powdery mildew. Iranian Journal of Plant Pathology, 50(2), 151-161. (In Persian with English abstract)

39- Spaepen, S., & Vanderleyden, J. (2011). Auxin and plant-microbe interactions, Cold Spring Harb Perspect Biol. https://doi.org/10.1101/cshperspect.a001438

40- Taiz, L., & Zeiger, E. (2010). Plant Physiology (5th ed.), Sinauer Associates, Inc., Sunderland.

41- Turan, M., Ekinci, M., Yildirim, E., Güneş, A., Karagöz, K., Kotan, R., & Dursun, A. (2014). Plant growth-promoting rhizobacteria improved growth, nutrient, and hormone content of cabbage (Brassica oleracea) seedlings. Turkish Journal of Agriculture and Forestry, 38, 327-333. https://doi.org/10.3906/tar-1308-62

42- Vlot, A.C., Dempsey, D.A., & Klessig, D.F. (2009). Salicylic acid, a multifaceted hormone to combat disease. Annual Review of Phytopathology, 47, 177-206. https://doi.org/10.1146/annurev.phyto.050908.135202

43- Vurukonda, S.S.K.P., Vardharajula, S., Shrivastava, M., & SkZ, A. (2015). Enhancement of drought stress tolerance in crops by plant growth promoting rhizobacteria. Microbiological Research, 184, 13-24. https://doi.org/10.1016/j.micres.2015.12.003

44- Wagner, G.J. (1979). Content and vacuole/ extra vacuole distribution of neutral sugars, free amino acids and anthocyanins in protoplasts. Plant Physiology, 64, 88-93. https://doi.org/10.1104/pp.64.1.88

45- Zhang, H., Murzello, C., Sun, Y., Kim, X., Mi, S.R., Jeter, R.M., Zak, J.C., Scot Dowd, E., & Pare, P.W. (2010). Choline and osmotic-stress tolerance induced in Arabidopsis by the soil microbe Bacillus subtilis (GB03). Molecular Plant-Microbe Interactions, 23, 1097-1104. https://doi.org/10.1094/MPMI-23-8-1097

46- Zhang, K.M., Yu, H.J., Shi, K., Zhou, Y.H., Yu, J.Q., & Xia, X.J. (2010). Photoprotective roles of anthocyanins in Begonia semperflorens. Plant Science, 179, 202-208. https://doi.org/10.1016/j.plantsci.2010.05.006

47- Zhu, J.H., Dong, K., Yang, Z.X., & Dong, Y. (2017). Advances in the mechanism of crop disease control by intercropping. Chin Journal of Ecology, 36, 1117-1126. https://doi.org/10.13292/j.1000-4890.201704.016