ISSN:
1365-3059
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Psorosis, sometimes also associated with ringspot symptoms, is a widespread and damaging disease of citrus in many parts of the world including South America and the Mediterranean basin. We describe the application of RT-PCR and DAS-ELISA diagnostics to an isolate of citrus ringspot virus (CtRSV-4) and other virus isolates associated with this disease. Fragments of cDNA from bottom-component RNA of CtRSV-4 were cloned and sequenced, and PCR primers were designed, 5′ACAATAAGCAAGACAAC upstream, and 5′CCATGTCACTTCTATTC downstream. RT-PCR experiments using these primers allowed detection of CtRSV-4 in infected citrus leaves down to a tissue dilution of 1/12 800 representing 2 μg of tissue, and less sensitive detection of the related citrus psorosis-associated virus (CPsAV90-1-1) and four other psorosis isolates from Argentina and the USA. In addition, CtRSV-4 particles were partially purified from local lesions in Chenopodium quinoa, and the preparations used to raise a rabbit antiserum. The antiserum was absorbed with extracts of healthy C. quinoa leaves, and a DAS-ELISA kit was prepared and tested for detection of CtRSV-4, CPsAV90–1-1, and other psorosis isolates from Argentina, the USA, Italy and Spain. The ELISA detected CtRSV-4 down to a tissue dilution of 1/1600, and most other psorosis isolates down to dilutions of 1/200–1/800. Three of a total of 20 heterologous isolates were consistently negative. Comparison of the PCR and ELISA results suggests that both methods can be used for detection of a range of psorosis isolates, but that variation of the viruses in the field might cause problems for any one diagnostic test.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1365-3059.1997.d01-81.x
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