Activity of ß-1,3-glucanase and ß-1,4-glucanase in two potato cultivars following challenge by the fungal pathogen Alternaria solani
Early blight of potato, caused by Alternaria solani, is a ubiquitous disease in many countries around the world. Our previous screening of several Iranian potato cultivars found that variation in resistance exists between two cultivars: ‘Diamond’ and ‘Granula’. Cultivar Diamond is more resistant to multiple isolates of A. solani when compared to cv. Granula. Furthermore, we have found that different pathogen isolates have varying degrees of infection. We monitored the activities of two pathogen-related (PR) glucanase proteins in Diamond and Granula in response to two isolates of A. solani with different degrees of virulence. ß-1,3-glucanase and ß-1,4-glucanase activities were recorded in healthy and diseased leaves of potatoes up to 10 days after inoculation. Their activities were found to be higher in diseased leaves when compared to those of uninfected leaves. Our data suggest that significantly reduced activities of theses enzymes in potato could be related to a lower degree of resistance or an increased ability of a more aggressive isolate to suppress PR protein expression.
KeywordsEarly blight Pathogen-related protein Solanum tuberosum
The authors are grateful to Dr. H. R. Etebarian (Department of Plant Protection, Aboryhan Campus, Tehran University, Tehran, Iran) for helpful suggestions. The authors also gratefully acknowledge the valuable support of Mr. M. R. Lak in the study.
- Buchel, A., & Linthorst, H. (1999). PR-1: A group of plant proteins induced upon pathogen infection. In S. Datta & S. Muthukrishnan (Eds.), Pathogenesis-related proteins in plants (pp. 21–47). Boca Raton, FL, USA: CRC Press LLC.Google Scholar
- Edreva, A. (2005). Pathogenesis-related proteins: Research progress in the last 15 years. General and Applied Plant Physiology, 31, 105–124.Google Scholar
- Gau, A. E., Koutb, M., Piotrowski, M., & Kloppstech, K. (2004). Accumulation of pathogenesis-related proteins in the apoplast of a susceptible cultivar of apple (Malus domestica cv. Elstar) after infection by Venturia inaequalis and constitutive expression of PR genes in the resistant cultivar Remo. European Journal of Plant Pathology, 110, 703–711.CrossRefGoogle Scholar
- Jeun, Y-Ch., & Buchenauer, H. (2001). Infection structures and localization of the pathogenesis-related protein AP24 in leaves of tomato plants exhibiting systemic acquired resistance against Phytophthora infestans after pre-treatment with 3-aminobutyric acid or tobacco necrosis virus. Journal of Phytopathology, 149, 141–153.CrossRefGoogle Scholar
- Lawrence, C. B., Singh, N. P., Qiu, J., Gardner, R. G., & Tuzun, S. (2000). Constitutive hydrolytic enzymes are associated with polygenic resistance of tomato to Alternaria solani and may function as an elicitor release mechanism. Physiological and Molecular Plant Pathology, 57, 211–220.CrossRefGoogle Scholar
- Littell, R. C., Milliken, G. A., Stroup, W. W., & Wolfinger, R. D. (1996). SAS® system for mixed models. Cary, NC, USA: SAS Institute Inc.Google Scholar
- Madhaiyan, M., Poonguzhali, S., Senthikumar, M., Seshadri, S., Chung, H., Yong, J., et al. (2004). Growth promotion and induction of systemic resistance in rice cultivar Co-47 (Oryza sativa) by Methylobacterium spp. Botanical Bulletin of Academia Sinica, 45, 315–324.Google Scholar
- Poupard, P., Parisi, L., Campion, C., Ziadi, S., & Simoneau, P. (2003). A wound- and ethephon-inducible PR-10 gene subclass from apple is differentially expressed during infection with a compatible and an incompatible race of Venturia inaequalis. Physiological and Molecular Plant Pathology, 62, 3–12.CrossRefGoogle Scholar
- Tonón, C., Guevara, G., Oliva, C., & Daleo, G. (2002). Isolation of a potato acidic 39 kDa β-1,3-glucanase with antifungal activity against Phytophthora infestans and analysis of its expression in potato cultivars differing in their degrees of field resistance. Journal of Phytopathology, 150, 189–195.CrossRefGoogle Scholar