01408naa a2200169 a 450000100080000000500110000800800410001910000150006024501930007526000090026852008330027765000120111065300090112265300190113165300290115077300590117916466751995-07-14       1986    bl ---       0--  u    #d1 aFLORES, R.  aDetection of citrus exocortis viroid in crude extracts by dot-blot hybridizationbConditions for reducing spurious hybridization results and for enhancing the sensitivity of the technique.  c1986  aDot-blot assays to detect citrus exocortis viroid (CEV), in clarified sap and unfractionated total nucleic acid preparations of CEV- infected Gynura aurantiaca and chrysanthemun, were impaired by the non-specific binding of the radioactive probe shown by the healty controls. This non-specific background was considerably reduced by the addition to the hybridization mixture, of the fraction of nucleic from healthy plants which are insoluble in 2 M LiCI (containing mainly the large ribosomal RNAs). Sample denaturation with formaldehyde was found to provide a high increase of hybridization, when compared with samples either denatured with formamide or directly spotted.Nitrocellulose was observed to be a better solid support than charge-modified nylon, in terms of the sensitivity of viroid detection by spot hybridization.  aviroids  acDNA  aDot-blot assay  aNucleic acid hybrization  tJournal of Virological methodsgv.13, p.161-169, 1986.