Abstract
Phytophthora root rot of avocado and Persea indica caused by Phytophthora cinnamomi was controlled by spraying or drenching with phosphorous acid Dartiallv neutralised with potassium hydroxide, or with phosethyl Al. Phosphoric acid drenches increased phytophthora root rot in avocado, whereas dolomitic limestone, gypsum or diammonium phosphate did not affect disease incidence. A twenty per cent solution of partially neutralised phosphorous acid when injected into the trunks of seven-year-old trees affected by phytophthora root rot permitted rapid recovery of trees over a 12 month period. Injections with phosethyl Al (Experimental formulation 2008), and a ten per cent solution of phosphorous acid, and soil applications of metalaxyl gave slower remission of disease symptoms.
This is a preview of subscription content, access via your institution.
References
Adams, F. and Conrad, J.P. (1953) — Transition of phosphite to phosphate in soils. Soil Science 75: 361–371.
Allen, J.E. (1969) — The preparation of agricultural samples for analysis by atomic absorption spectroscopy. Varian Aerograph pp. 1–9, Varian Tectron, U.S.A.
Broadbent, P. and Baker, K.F. (1974) — Behaviour of Phytophthora cinnamomi in soils suppressive and conducive to root rot. Australian Journal of Agricultural Research 25: 121–137.
Buitendag, C.H. and Bronkhorst, C.J. (1980) — Injection of insecticides into tree trunks — a possible new method for the control of citrus pests. Citrus and Sub-tropical Fruit Journal 556: 5–7.
Darvas, J.M. (1984) — Zinc supplemented to avocado trees in conjunction with root rot control injections. South African Avocado Growers’ Association Yearbook 7: 79.
Darvas, J.M., Toerien, J.C. and Milne, D.L. (1983) — Injection of established avocado trees for the effective control of Phytophthora root rot. Citrus and Sub-tropical Fruit Journal 591: 7–10.
Darvas, J.M., Toerien, J.C. and Milne, D.L. (1984) — Control of avocado root rot by trunk injection with phosethyl-Al. Plant Disease 68: 691–693.
Fenn, M.E. and Coffey, M.D. (1984) — Studies on the in vitro and in vivo antifungal activity of fosetyl-Al and phosphorous acid. Phytopathology 74: 606–611.
Lee, B.S. and Zentmyer, G.A. (1982) — Influence of calcium nitrate and ammonium sulphate on Phytophthora root rot of Persea indica. Phytopathology 72: 1558–1564.
Marks, G.C., Kassaby, F.Y. and Fagg, P.C. (1975) — Die-back tolerance in eucalypt species in relation to fertilization and soil populations of Phytophthora cinnamomi. Australian Journal of Botany 21: 53–65.
Pegg, K.G., Forsberg, L.I. and Whiley, A.W. (1982) — Avocado root rot. Queensland Agricultural Journal 108: 162–168.
Synman, C.P. and Darvas, J.M. (1982) — Die uitwerking van kalsium op wortelorot by avokadi. South African Avocado Growers’ Association Yearbook 5: 80–84.
Trochoulias, T. (1982) — Soil management trial, Alstonville. In: Proceedings Avocado Fieid Days, Australian Avocado Growers’ Federation, Alstonville pp. 11-13.
Whiley, A.W., Carseldine, M.L., Saranah, J.B. and Coey, R.G. (1985) — Growth patterns and seasonal changes in concentration of major nutrients in leaves of two cultivars of avocado (Persea americana Mill.). Scienta Horticulture. In press.
Whiley, A.W., Pegg, K.G., Saranah, J.B. and Forsberg, L.I. (1985) — The control of Phytophthora root rot of avocado with fungicides and the effect of this disease on water relations, yeild and ring neck. Australian Journal of Experimental Agriculture and Animal Husbandry. In press.
Williams, D.J., Beach, B.G.W., Horriere, D. and Marechal, G. (1977) — L.S. 74–783, a new systemic fungicide with activity against phycomycete diseases, pages 565–573 in: Proceedings British Crop Protection Conference, Pest and Diseases, 21–24 November 1977. Brighton, England 1045 pp.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Pegg, K.G., Whiley, A.W., Saranah, J.B. et al. Control of phytophthora root rot of avocado with phosphorus acid. Australasian Plant Pathology 14, 25–29 (1985). https://doi.org/10.1071/APP9850025
Issue Date:
DOI: https://doi.org/10.1071/APP9850025
Keywords
- Phosphorous Acid
- Australasian Plant Pathology
- Metalaxyl
- Zinc Sulphate
- Diammonium Phosphate