Aspects of mature plant resistance in wheat to Puccinia striiformis Westend
Aspects of mature plant resistance in wheat to Puccinia striiformis Westend
The production of wheat cultivars with durable resistance to yellow rust is a major consideration in breeding programmes. Investigation of resistance components, the growth stages at which they operate, and mechanisms of resistance may yield information which would be useful in the rapid identification of durable resistance. Several components of resistance were investigated at various growth stages in a range of wheat cultivars exhibiting mature plant resistance. Spore gemination and penetration were reduced at adult growth stages on resistant compared to susceptible cultivars, but their usefulness as resistance components is questionable. Lengths of leaves colonised from initial point inoculations showed significant varietal differences at seedling stages. Measurements of colony sizes, pustule size and density, and latent period, generally correlated well with length of leaf colonised. Measurement of colonisation by a chitin assay detected varietal differences at seedling and adult growth stages. Seedling differences correlated well with other measurements of growth at that stage. The assay showed that, relative to a susceptible cultivar, some cultivars did not show increased resistance over the period of growth from the third (seedling) leaf to the flag leaf. In the same cultivars, the amount of host cell necrosis increased over the same period. The significance of this in terms of the relation between necrosis and resistance is discussed. An attempt to detect possible production or initial presence of antifungal substances in resistant cultivars using a spore germination assay was unsuccessful due to variability of germination levels. The possibility that lignification is involved in resistance to yellow rust was investigated, but results were inconclusive, and more sensitive methods of assaying lignin may be required. (D68638/86)
University of Southampton
1984
Thomas, Jane Elizabeth
(1984)
Aspects of mature plant resistance in wheat to Puccinia striiformis Westend.
University of Southampton, Doctoral Thesis.
Record type:
Thesis
(Doctoral)
Abstract
The production of wheat cultivars with durable resistance to yellow rust is a major consideration in breeding programmes. Investigation of resistance components, the growth stages at which they operate, and mechanisms of resistance may yield information which would be useful in the rapid identification of durable resistance. Several components of resistance were investigated at various growth stages in a range of wheat cultivars exhibiting mature plant resistance. Spore gemination and penetration were reduced at adult growth stages on resistant compared to susceptible cultivars, but their usefulness as resistance components is questionable. Lengths of leaves colonised from initial point inoculations showed significant varietal differences at seedling stages. Measurements of colony sizes, pustule size and density, and latent period, generally correlated well with length of leaf colonised. Measurement of colonisation by a chitin assay detected varietal differences at seedling and adult growth stages. Seedling differences correlated well with other measurements of growth at that stage. The assay showed that, relative to a susceptible cultivar, some cultivars did not show increased resistance over the period of growth from the third (seedling) leaf to the flag leaf. In the same cultivars, the amount of host cell necrosis increased over the same period. The significance of this in terms of the relation between necrosis and resistance is discussed. An attempt to detect possible production or initial presence of antifungal substances in resistant cultivars using a spore germination assay was unsuccessful due to variability of germination levels. The possibility that lignification is involved in resistance to yellow rust was investigated, but results were inconclusive, and more sensitive methods of assaying lignin may be required. (D68638/86)
This record has no associated files available for download.
More information
Published date: 1984
Identifiers
Local EPrints ID: 461701
URI: http://eprints.soton.ac.uk/id/eprint/461701
PURE UUID: 5de848e2-c0e0-472e-be70-b4a2e24b94ee
Catalogue record
Date deposited: 04 Jul 2022 18:52
Last modified: 04 Jul 2022 18:52
Export record
Contributors
Author:
Jane Elizabeth Thomas
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics