Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/15/2006
Publication Date: 6/22/2006
Citation: Eid, S., Abou-Jawdah, Y., El-Mohtar, C., Sobh, H., Havey, M.J. 2006. Screening cucumber accessions for resistance to cucurbit yellow stunting disorder virus [abstract]. Proceedings of the 12th Mediterranean Phytopathological Congress. p. 115 Interpretive Summary:
Technical Abstract: Cucurbit yellow stunting disorder virus (CYSDV) is the major virus disease of greenhouse-grown cucumbers. CYSDV is transmitted to cucurbit crops by the whitefly Bemisis tabaci, causing between 30 and 50% yield losses. It was reported in several countries in the Mediterranean basin, Portugal, Morocco and the United States. Development of resistant cultivars represents an economically and environmentally sound approach to management of this disease. Over hundred cucumber accessions were evaluated for resistance to CYSDV under controlled inoculation conditions. Whiteflies were reared on broccoli and then allowed an acquisition access feeding period of two days and an inoculation access feeding period of two to four days. About 40- 50 whiteflies were used per seedling at the first true leaf stage. The experiment was conducted over three growing seasons. Only tolerant accessions and the susceptible controls were included during the second and third growing seasons. ELISA tests, using antibodies produced against the recombinant CYSDV- coat protein, were performed 18 weeks after inoculation to compare relative virus concentrations between selected tolerant accessions and the susceptible controls. A few accessions including PIs 293432, 605923, and Ames 13334 showed some tolerance to the disease expressed as delayed symptom expression, milder symptoms, and a lower percentage of infected plants as compared to susceptible cucumbers. Serological tests showed that none of these accessions were immune to CYSDV, and that virus concentrations in the middle leaves of the tolerant accessions were significantly lower than those of the susceptibles. These CYSDV-tolerant accessions may be included in breeding programs. However, it is first preferred to study the mode of inheritance of CYSDV tolerance in these accessions.