Variation in resistance to Marssonina rosae (Lib.) Died. among different Rosa L. cultivars and species including three dogrose species (Rosa sect. Caninae)
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- 作者：B. Ulrika Carlson-Nilsson and Campbell G. Davidson
- 关键词：Blackspot ; Rosa dumalis ; R. rubiginosa ; R. villosa ; Diplocarpon rosae ; Genetic variation
- 刊名：Scientia Horticulturae
- 出版年：2006
- 出版时间：15 August 2006
- 年：2006
- 卷：109
- 期：4
- 页码：353-360
- 全文大小：192 K
文摘
Blackspot is often regarded as the most destructive disease in garden roses. Resistance to blackspot, caused by Marssonina rosae, has proved difficult to achieve in different breeding programs. In the present study, a greenhouse test where rose cuttings (5–8 months old) were infected with a polysporous suspension of Marssonina rosae was compared with an evaluation of natural infection of blackspot in a field trial with the same accessions (experiment I). Three different evaluation methods for screening for resistance to blackspot in the greenhouse were tested as well: (A) percentage of infected leaves, (B) rating from 0 to 6 considering number of spots and number of leaves/leaflets infected, (C) rating from 0 to 3 considering the total area covered by the spots (experiments IIa and b). The study included different species, cultivars and breeding lines (Rosa multiflora-hybrids). Plants representing three wild species from the section Caninae, native to Sweden, were included. The significant correlations between infection data from the three evaluation methods, respectively, and from the field trial indicated that the inoculation method used in the present study could be a useful alternative or complement to a field study. Significant correlations were found as well between the three evaluation methods, for all pairwise combinations. The evaluation method most easy to use (percentage of infected leaves with no consideration of the area of the spots) appeared to be as good as the more complicated and time consuming methods and can be recommended for a fast and easily performed test of blackspot resistance. Significant differences were found between accessions in the greenhouse tests. Three of the breeding lines together with Président de Sèze and R. carolina were completely free from infections and all R. rubiginosa-genotypes obtained mean values of less than 12 % infected leaves. The breeding lines (R. multiflora-hybrids) and the species, were less infected by blackspot than the different cultivars included. Only three of the cultivars showed less than 10 % infected leaves.