Abstract
This is the first report of Phytophthora megasperma Drechs. causing root rot of white clover (Tryolium repens L.) in Australia. The fungus was isolated from diseased and apparently healthy white clover roots and nodules, from a wide range of sites in northern Victoria. The morphology of the fungus is described and compared with other members of the P. megasperma complex. Pathogenicity studies showed that root rot caused by the fungus occurred more commonly on nodulated than un-nodulated plants. The fungus was frequently observed to sporulate profusely from discoloured nodules found on infected plants and this suggests that nodules may provide the site for infection.
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References
Christensen, M.J., Falloon, R.E. and Skipp, R.A. (1988) — A Petri plate technique for testing pathogenicity of fungi to seedlings and inducing fungal sporulation. Australasian Plant Pathology 17: 45–47.
Froshier, F.I. and Barnes, D.K. (1973) — Field and greenhouse selection for phytophthora root rot resistance in alfalfa. Crop Science 13: 735–738.
Hansen, E.M. and Ham, P.B. (1983) — Morphological differentiation of host-specialised groups of Phytophthora megasperma. Phytopathology 73: 129–134.
Hansen, E.M. and Maxwell, D.P. (1991) — Species of the Phytophthora megasperma complex. Mycologia 83: 376–381.
Hansen, E.M., Brasier, C.M., Shaw, D.S and Hamm, P.B. (1986) — The taxonomic structure of Phytophthora megasperma: Evidence for emerging biological species groups. Transactions of the BritishMycolologicalSociety 87: 557–573.
Heritage, A,, Castles, C.J and Pierpoint, J. (1988) — Field survey of Phytophthora root rot in commercial soybean crops of the irrigated regions of southern Australia. In Proceedings of the 5th Australian Soybean Research Workshop, Tamworth, NSW, 11–13 Oct 1988. pp. 39–42.
Hilderbrand, D.C. (1959) — A root and stalk rot of soybean caused by Phytophthora megasperma Dreschsler var. sojea. Canadian Journal of Botany 37: 927–957.
Irwin, J.A.G and Dale, J.L (1982) — Relationships between Phytophthora megaspema isolates from chickpea, lucerne and soybean. Australian Journal of Botany 30: 199–210.
Irwin, J.A.G and Jones, R.M. (1977) — The role of fungi and nematodes as factors associated with death of white clover (Trifolium repens) stolons over summer in south-eastern Queensland. Australian Journal of Experimental Agriculture and Animal Husbandry 17: 789–794.
Johnston, A. and Booth, C. (Eds) (1983) — Plant Pathologists Pocketbook. Commonwealth Mycological Institute, Kew.
Kaufman, J. J and Gerdemann, J. W. (1958) — Root and stem rot of soybeans caused by Phytophthora sojae f: sp. Phytopathology 48: 201–208.
Kuan, T.L. and Erwin, D.C. (1980) — Formae speciales differentiation of Phytophthora megasperma isolated from soybean and alfalfa. Phytopathology 70: 333–338.
Martin, F.M. (1982) — Potential productivity of irrigated pastures. In Agronomy Australia 1982. Proceedings of the Second Australian Agronomy Conference, Wagga Wagga. Australian Society of Agronomy
Mason, W., Kelly, K., Blaikie, S. and Stockdale, R. (1986) — New directions for irrigated pastures. In Dairy Production Research Report. pp. 4–21. Department of Agriculture and Rural Affairs, Victoria. Agdex 4101960.
Newhook, F.J., Waterhouse, G.M. and Stamps, D.J. (1979) — Tabular key to the species of Phytophthora DeBary. Commonwealth Mycological Institute: Mycological Paper 143: 20 pp.
Pratt, R.G. (1981) — Morphology, pathogenicity and host range of Phytophthora megaspema, P. erythroseptica and P. parasitica from arrowleaf clover. Phytopathology 71: 276–282.
Ribiero, O.K., Envin, D.C. and Khan, R.A. (1978) — High-temperature phytophthora pathogenic to roots of alfalfa. Phytopathology 68: 155–161.
Ryley, M.J., Mosetter, H.F. and Rose, J.L. (1989) — Yield losses of soybeans due to Phytophthora megasperma f: sp. glycinea. Australian Journal of AgriculturalResearch 40: 1161–69.
Skipp, R.A. and Cristensen, M.J. (1982) — Invasion of white clover roots by fungi and other soil microorganisms. III. The capacity of fungi isolated from white clover roots to invade seedling root tissue. New Zealand Journal of AgriculturalResearch 25: 97–101.
Troedson, R.J., Ryley, M.J., Byth, D.E. and Irwin, J.A.G. (1991) — Effect of phytophthora root and stem rot on the response of field-grown soybean to saturated soil culture. Australian Journal of Agricultural Research 42: 791–799.
Waterhouse, G.M. (1963) — Key to the species of Phytophthora DeBary. Commonwealth Mycological Institute: Mycological Paper 92: 22 pp.
Waterhouse, G.M. (1970) — The genus Phytophthora DeBary. Commonwealth Mycological Institute: Mycological Paper 122: 59 pp.
Waterhouse, G.M. and Waterston, J.M. (1966) — Phytophthora megasperma. In: CMI Descriptions of Pathogenic Fungi and Bacteria No. 1 15
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Williams, B.L., Pascoe, I.G. Phytophthora megasperma, a pathogen of Trifolium repens in irrigated pastures of northern Victoria. Australasian Plant Pathology 23, 88–96 (1994). https://doi.org/10.1071/APP9940088
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DOI: https://doi.org/10.1071/APP9940088