Abstract
This article is concerned with the developmental processes that prime the appressorium of Magnaporthe grisea for mechanical penetration of the host surface. Experiments have shown that melanized appressoria generate enormous turgor pressure following the accumulation of high concentrations of cytoplasmic osmolytes, and thereby deliver substantial invasive force at the tip of a slender penetration hypha. Recent molecular genetic studies provide authoritative evidence for the central role played by melanin biosynthesis in the operation of the appressorium, and still other studies have revealed the identity of some of the osmolytes responsible for turgor generation. However, our picture of appressorial function remains limited by a number of problems: the maximum level of appressorial pressure is still questionable, the metabolic source of the cytoplasmic osmolytes is a mystery, and the processes that control melanization of the appressorial wall are poorly understood. Progress toward the resolution of these issues is discussed.
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Davis, D.J., Burlak, C., Money, N.P. (2000). Biochemical and Biomechanical Aspects of Appressorial Development in Magnaporthe Grisea . In: Tharreau, D., Lebrun, M.H., Talbot, N.J., Notteghem, J.L. (eds) Advances in Rice Blast Research. Developments in Plant Pathology, vol 15. Springer, Dordrecht. https://doi.org/10.1007/978-94-015-9430-1_30
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DOI: https://doi.org/10.1007/978-94-015-9430-1_30
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