Summary
An assay for resistance of onion to pink root Pyrenochaeta terrestris was developed, employing infested vermiculite medium with an adequate inoculum concentration of the fungus to minimize escapes of susceptible plants.
Plant material other than seed was used. Either root-excised 6–8 week-old seedlings or onion sets were planted in infested vermiculite, and kept for two successive 2-week periods of growth differing in light and temperature regimes. During the first phase a short-day regime of 10 h and 17±1°C was kept, under which a vigorous root system was obtained. For an additional 12–14 days under 26±1°C and 12 h light the prolific roots were then exposed to the optimal temperature for disease development.
This technique enables one to distinguish easily between susceptible Allium cepa material and a resistant line of A. fistulosum.
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References
Gorenz A. M., R. H. Larson & J. C. Walker, 1949. Factors affecting pathogenicity of pink root of onions. J. agric. Res. 78: 1–18.
Iglesias J., N. S. Urquhart & J. N. Corgan, 1980. Greenhouse and field plot technique for onion pink root screening. HortScience 15: 49 (abstr.).
Jones H. A. & B. A. Perry, 1956. Inheritance of resistance to pink root in the onions. J. Hered. 47: 33–34.
Joubert T. G., G. La & C. E. Rappard, 1970. Seed-size and vegetable crops. Fmg S. Afr. 46: 35–36.
Nichols C. G., W. H. Gabelman, R. H. Larson & J. C. Walker, 1965. The expression and inheritance of resistance to pink root in onion seedlings. Phytopathology 55: 752–756.
Rabinowitch H. D., J. Katan & J. Rotem, 1981. The response of onions to solar heating, agriculture practices and pink root disease. Scient. Hort. 15: 331–340.
Sneh B., D. Netzer & J. Krikun, 1974. Isolation and identification of Pyrenochaeta terrestris from soil on dilution plates. Phytopathology 64: 275–276.
Walker J. C., 1953. Hazards to onions in many areas. In: Plant disease; the Year Book of Agriculture 1953. U.S. Dep. Agric., Wash., D.C. pp. 431–435.
Watson R. D. 1961. Rapid identification of the onion pink root fungus. Pl. Dis. Reptr. 45: 289.
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Contribution from the Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel. No. 1022-E, 1984 series.
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Netzer, D., Rabinowitch, H.D. & Weintal, C. Greenhouse technique to evaluate onion resistance to pink root. Euphytica 34, 385–391 (1985). https://doi.org/10.1007/BF00022933
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DOI: https://doi.org/10.1007/BF00022933