Abstract
Proliferation and collapse of subcuticular hyphae of Venturia nashicola race 1 were studied ultrastructurally, after inoculation of susceptible Japanese pear cv. Kousui, resistant Japanese pear cv. Kinchaku, resistant Asian pear strain Mamenashi 12 and nonhost European pear cv. Flemish Beauty leaves, to understand the nature of the resistance mechanism. After cuticle penetration by the pathogen, the hyphae were observed at lower frequency in epidermal pectin layers and middle lamellae of leaves of the three resistant plants than in those of susceptible ones. This result suggested that fungal growth was suppressed in the incompatible interaction between pear and V. nashicola race 1. In the pectin layers of all inoculated plants, some hyphae had modifications such as breaks in the plasmalemma with plasmolysis, necrotic cytoplasm and degraded cell walls. More hyphae had collapsed in the leaves of the three resistant plants than in those of the susceptible cv. Kousui. In collapsed hyphae, the polymerized cell walls broke into numerous fibrous and amorphous pieces, showing that the scab resistance might be associated with cell wall-degrading enzymes from pear plants.
Similar content being viewed by others
References
Abe K, Kotobuki K (1998) Polygenic inheritance of necrotic reaction to pear scab (Venturia nashicola Tanaka et Yamamoto) in Japanese pear (Pyrus pyrifolia Nakai) and Chinese pear (P. ussuriensis Maxim.). J Japan Soc Hort Sci 67:839–842
Abe K, Kurihara A (1993) Species and varietal differences in scab resistance of pear (in Japanese). J Japan Soc Hort Sci 61:789–794
Abe K, Kotobuki K, Saito T, Terai O (2000) Inheritance of resistance to pear scab from European pears to Asian pears. J Japan Soc Hort Sci 69:1–8
Buchanan BB, Gruissem W, Jones RL (2001) Cell wall fortifications and extracellular activities contribute to plant disease resistance responses. In: Buchanan BB, Gruissem W, Jones RL (eds) Biochemistry & molecular biology of plants. American Society of Plant Physiologists, Rockville, ML, USA, pp 1135–1136
Collinge DB, Slusarenko AJ (1987) Plant gene expression in response to pathogens. Plant Mol Biol 9:389–410
Collinge DB, Kragh KM, Mikkelsen JD, Nielsen KK, Rasmussen U, Vad K (1993) Plant chitinases. Plant J 3:31–40
De Lorenzo G, Ferrari S (2002) Polygalacturonase-inhibiting proteins in defense against phytopathogenic fungi. Curr Opin Plant Biol 5:295–299
Faize M, Faize L, Ishizaka M, Ishii H (2004) Expression of potential defense responses of Asian and European pears to infection with Venturia nashicola. Physiol Mol Plant Pathol 64:319–330
Faize M, Sugiyama T, Faize L, Ishii H (2003) Polygalacturonase-inhibiting protein (PGIP) from Japanese pear: possible involvement in resistance against scab. Physiol Mol Plant Pathol 63:319–327
Heath MC (2000) Nonhost resistance and nonspecific plant defenses. Curr Opin Plant Biol 3:315–319
Ishii H, Udagawa H, Nishimoto S, Tsuda T, Nakashima H (1992) Scab resistance in pear species and cultivars. Acta Phytopathol Entomol Hung 27:293–298
Ishii H, Watanabe H, Tanabe K (2002) Venturia nashicola: pathological specialization on pears and control trial with resistance inducers. Acta Hort 587:613–621
Ishii H, Yanase H (2000) Venturia nashicola, the scab fungus of Japanese and Chinese pears: a species distinct from V. pirina. Mycol Res 104:755–759
Isshiki A, Akimitsu K, Ishii H, Yamamoto H (2000) Purification of polygalacturonases produced by the pear scab pathogens, Venturia nashicola and Venturia pirina. Physiol Mol Plant Pathol 56:263–271
Mauch F, Mauch-Mani B, Boller T (1988) Antifungal hydrolases in pea tissue. II. Inhibition of fungal growth by combinations of chitinase and β-1,3-glucanase. Plant Physiol 88:936–942
Park P, Fujiwara T, Fukutomi M (1977) Application of alkaline bismuth staining solution to Japanese pear leaf and fungal cells. J Electron Microsc 26:335–337
Park P, Ishii H, Adachi Y, Kanematsu S, Ieki H, Umemoto S (2000) Infection behavior of Venturia nashicola, the cause of scab on Asian pears. Phytopathology 90:1209–1216
Tanaka S, Yamamoto S (1964) Studies on pear scab. II. Taxonomy of the causal fungus of Japanese pear scab (in Japanese). Ann Phytopathol Soc Jpn 29:128–136
Weibel ER (1979) Practical methods for biological morphometry. In: Weibel ER (eds) Stereological Method, vol 1. Academic, London, pp 1–348
Weibel ER (1980) Theoretical foundations. In: Weibel ER (eds) Stereological Method, vol 2. Academic, London, pp 1–348
Wessels JGH (1986) Cell wall synthesis in apical hyphal growth. Int Rev Cytol 104:37–79
Wessels JGH (1988) A steady state model for apical wall growth in fungi. Acta Bot Neerl 37:3–16
Acknowledgments
We are grateful to Dr. K. Ikeda (Graduate School of Science and Technology, Kobe University) for useful discussion.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Jiang, S., Park, P. & Ishii, H. Ultrastructural study on scab resistance expressed in epidermal pectin layers of pear leaves. J Gen Plant Pathol 73, 314–323 (2007). https://doi.org/10.1007/s10327-007-0034-8
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10327-007-0034-8