Detection and Management of Downy Mildew in Rose Rootstock

Plant Disease
B J AegerterR M Davis

Abstract

A technique utilizing the polymerase chain reaction (PCR) was developed to investigate the occurrence and location of Peronospora sparsain dormant, woody rose tissues. PCR primers were designed to amplify the internal transcribed spacer region of the ribosomal DNA of the pathogen. Inhibition of the reaction by plant compounds was minimized by optimizing the reagents used in the extraction of DNA from roses and in the amplification reaction. The PCR assay was capable of detecting as little as 2 pg of DNA from P. sparsa against a background of 4 ng of DNA from rose cane cortex. With this method, DNA of P. sparsa was detected in the cortex of stem and root tissues of symptomatic plants. Pathogen DNA also was detected in the cortex of crown tissues of asymptomatic mother plants used as a source of propagation materials. Epifluorescent and differential interference contrast microscopy were used to confirm the presence of abundant hyphae and oospores within the stem cortex of infected canes. Preplant treatments of dormant rootstock cuttings in fungicides or hot water were evaluated during natural outbreaks of the disease in commercial rose nurseries. In three trials conducted over 2 years, a 10-min preplant dip in the systemic fungic...Continue Reading

References

Jul 11, 1995·Nucleic Acids Research·S H De BoerS Chittaranjan

❮ Previous
Next ❯

Related Concepts

Related Feeds

Antifungals

An antifungal, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis, cryptococcal meningitis, and others. Discover the latest research on antifungals here.