Alleviation of Phytophthora capsici-induced oxidatıve stress by foliarly applied proline in Capsicum annuum L.


  • Esra Koç Ankara University, Faculty of Science, Department of Biology


antioxidants, Capsicum annuum, Phytophthora root rot, proline, oxidative stress tolerance


Phytophthora capsici is a highly destructive pathogen of pepper. To examine whether proline modifies the levels of plant defense compounds produced in response to P. capsici-induced stress, pepper seedlings were infected with P. capsici-22 in the presence of proline (1 mM, 10 mM) or in its absence. Proline was sprayed on the leaves of CM-334 and Kekova pepper cultivars prior to inoculation. CM-334 was more resistant to P. capsici-22, while the Kekova cultivar exhibited a sensitive reaction. P. capsici-22 increased the total phenolic compound and H2O2 levels, as well as phenylalanine ammonia-lyase, polyphenol oxidase and peroxidase activities in pepper seedlings. The application of exogenous proline further increased the activities of phenylalanine ammonia-lyase, polyphenol oxidase and peroxidase, as well as the total levels of phenolic compounds and the fresh and dry weights of the plants on the 5th and 7th days post treatment. After proline application, the highest catalase activity was found in both cultivars on the 5th day of the 10 mM proline + P. capsici application. On all days of the experiment, the applications caused a decrease in disease severity, necrosis length and H2O2 levels in both cultivars. In addition, proline decreased the colony growth of P. capsici and the number of zoospores. This finding indicates that enzymes and total phenolic compound levels protect the pepper seedlings against stress-related damage. Moreover, proline has the potential to directly scavenge free radicals and promote enzyme activity in pepper seedlings under P. capsici stress. These results suggest that foliar application of proline is an effective way to improve the stress tolerance of pepper to P. capsici.

Received: July 14, 2016; Revised: October 22, 2016; Accepted: December 1, 2016; Published online: December 15, 2016

How to cite this article: Koç E. Alleviation of Phytophthora capsici-induced oxidatıve stress by foliarly applied proline in Capsicum annuum L. Arch Biol Sci. 2017;69(4):733-42.


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Kim D, Lee JH, Choi W. Analysis of genes expressed during pepper-Phytophthora capsici interaction using EST Technology. J Life Sci. 2014;24(11):1187-92.

Leonian LH. Stem and fruit blight of peppers caused by Phytophthora capsici sp. Nov. Phytopathol. 1922;12:401-8.

Kamoun S, Furzer O, Jones JD, Judelson HS, Ali GS, Dalio RJ, Roy SG. The top 10 oomycete pathogens in molecular plant pathology. Mol Plant Pathol. 2015;16:413-4.

Sun WX, Jia YJ, O’Neil NR, Feng BZ, Zhang XG. Genetic diversity in Phytophthora capsici from eastern China. Can J Plant Pathol. 2008;30:414-24.

Abak KA, Pitrat M. A study on resistance to root rot disease (Phytophthora capsici Leon.) in peppers. AUAF annual. 1980;933-47.

Garcia AC, Arispuro HE, Tellez MAM. Cell metabolism – cell homeostasis and response. In: Paula B, editor. Oligoglucan elicitor effects during plant oxidative stress. Rijeka, Croatia: Intech; 2012. p. 1-12.

Hayat S, Hayat Q, Alyemeni MN, Wani AS, Pichel J, Ahmed A (2012) Role of proline under changing environments. Plant Sign Behav. 2012;7(11):1456-66.

Shao H, Chu L, Shao M, Jaleel CA, Hong-mei M. Higher plant antioxidants and redox signaling under environmental stresses. C R Biol. 2008;331:433-41.

Ali Q, Anwar F, Ashraf M, Saari N, Perveen R. Ameliorating effects of exogenously applied proline on seed composition, seed oil quality and oil antioxidant activity of maize (Zea mays L.) under drought stress. Int J Mol Sci. 2013;14:818-35.

Pochard E, Molat M, Dominquez J. Etude de deux nouvelles sources de resistance a Phytophthora capsici Leon. Chezle piment: confirmation de l’existence de trois composantes distinctes dans la resistance. Agronomie. 1983;3:333-42.

Jones DR, Unwin CH, Ward EWB. Capsidiol induction in pepper fruit during interactions with Phytophthora capsici and Monilinia fructicola. Phytopathol. 1975;65:1417-9.

Jones DR, Graham WG, Ward EWB. Ultrastructural changes in pepper cells in a compatible interaction with Phytophthora capsici. Phytopathol. 1974;1084-90.

Koç E, Üstün AS, İşlek C, Arıcı YK. Defence responses in leaves of resistant and susceptible pepper cultivars infected with different inoculum concentrations of Phytophthora capsici Leon. Sci Horticul. 2011;128(4):434-42.

Kim YJ, Hwang BK, Park KW. Expression of age-related resistance in pepper plants infected with P. capsici. Plant Dis. 1989;73:745-7.

Ochoa-Alejo N., Salgado Garcilia R. Phenylalanine ammonia-lyase activity and capsaicin-precursor compounds in p-fluorophenylalanine-resistant and sensitive variant cells of chili pepper (Capsicum annuum). Physiol Plant. 1992;85:173-9.

Ochoa-Alejo N, Gómez-Peralta JE. Activity of enzymes involved in capsaicin biosynthesis in callus tissue and fruits of chili pepper (Capsicum annuum L.). J Plant Physiol. 1993;141(2):147-52.

Zheng HZ, Cui CL, Zhang YT, Dan W, Yu J, Yong KK. Active changes of lignification-related enzymes in pepper response to Glomus intraradices and/or Phytophthora capsici. J Zhejiang Univ SCI. 2005;6(8):778-6.

Lin CC, Kao CH. Abscisic acid induced changes in cell wall peroxidase activity and hydrogen peroxide level in roots of rice seedlings. Plant Sci. 2001;160(2):323-9.

Aebi H. Catalase in vitro. Methods Enzymol. 1984; 105:121-6.

Gayosa C, Pomar F, Merino F, Bernal MA. Oxidative metabolism and phenolic compounds in Capsicum annuum L. var. annuum infected by Phytophthora capsici Leon. Sci Hortic. 2004;102:1-13.

Singleton VL, Orthofer R, Lamuela-Raventos RM. Analysis of total phenols and other oxidation substrates and antioxidants by means of Folin–Ciocalteu reagent. Methods Enzymol.1999; 299:152-78.

Velikova V, Yordanov I, Edreva A. Oxidative stress and some antioxidant systems in acid rain treated bean plants. Protective role of exogenous polyamines. Plant Sci. 2000;151:59-66.

Sharma P, Jha AB, Dubey RS, Pesserakli M. Reactive oxygen species, oxidative damage, and antioxidative defense mechanism in plants under stressful conditions. J Bot. 2012;1-26.

Ahmed CB, Rouina BB, Sensoy S, Boukhriss M, Abdullah FB. Exogenous proline effects on photosynthetic performance and antioxidant defense system of young olive tree. J Agric Food Chem. 2010;58(7):4216-22.

Rady MM, Taha RS, Mahdi AHA. Proline enhances growth, productivity and anatomy of two varieties of Lupinus termis L. grown under salt stress. S Afr J Bot. 2016;102:221-7.

Mandal S, Acharya P, Kar I. Reactive oxygen species signalling in eggplant in response to Ralstonia solanacearum infection. J Plant Pathol. 2014;96(3):525-34.

Sharma P, Dubey RS. Modulation of nitrate reductase activity in rice seedlings under aluminium toxicity and water stress: role of osmolytes as enzyme protectant. J Plant Physiol. 2005; 162:854-64.

Islam MM. Exogenous proline and glycinebetaine increase antioxidant enzyme activities and confer tolerance to cadmium stress in cultured tobacco cells. J Plant Physiol. 2009;166:1587-97.

Reddy PS, Jogeswar G, Rasineni GK, Maheswari M, Reddy AR, Varshney RK, Kishor PBV. Proline over-accumulation alleviates salt stress and protects photosynthetic and antioxidant enzyme activities in transgenic sorghum [Sorghum bicolor (L.) Moench]. Plant Physiol Biochem. 2015;94:104-13.

Moschou PN, Wu J, Cona A, Tavladorki P, Angelini R. The polyamines and their catabolic products are significant players in the turnover of nitrogenous molecules in plants. J Exp Bot. 2012;63(14):5003-15.

Kahlaoui B, Hachicha M, Teixeira J, Misle E, Fidalgo F, Hanchi B. Response of two tomato cultivars to field-applied proline and salt stress. J Stress Physiol Biochem. 2013;9(3):357-65.

El-Naggar HM. 2012. Phenylalanine ammonia-lyase (PAL) gene activity in response to proline and tyrosine in rosemary callus culture African J Biotech. 2012;11(1):159-63.

Nounjan N, Nghia PT, Theerakulpisut P. Exogenous proline and trehalose promote recovery of rice seedlings from salt-stress and differentially modulate antioxidant enzymes and expression of related genes. J Plant Physiol. 2012;169(6):596-604.

Ali Q, Anwar F, Ashraf M, Saari N, Perveen R. Ameliorating effects of exogenously applied proline on seed composition, seed oil quality and oil antioxidant activity of maize (Zea mays L.) under drought stress. Int J Mol Sci. 2013;14:818-35.




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Koç E. Alleviation of Phytophthora capsici-induced oxidatıve stress by foliarly applied proline in Capsicum annuum L. Arch Biol Sci [Internet]. 2017Oct.18 [cited 2022Aug.18];69(4):733-42. Available from: