Chrysanthemum Chlorotic Mottle Viroid Research Articles

Chlorosis in healthy and viroid-infected plants exposed to the steam additive diethylaminoethanol

Diethylaminoethanol (DAE), a neutralizing amine used to prevent corrosion of steam condensate lines, was found to cause chlorosis in young leaves of chrysanthemum, tomato, corn and bean. Sensitivity of corn and chrysanthemum to DAE was cultivar-dependent; chrysanthemum cultivar ‘Indianapolis White’ was sensitive to low concentrations of DAE, while ‘Bonnie Jean’, ‘Velvet Ridge’ and ‘Mistletoe’ were less so, and corn ‘3XD50’ was sensitive to DAE while ‘Ohio 28’ was not. The presence of latent chrysanthemum chlorotic mottle viroid (ChCMV-L) increased the sensitivity of ‘Bonnie Jean’ and ‘Velvet Ridge’ to DAE. Infection of tomatoes with mild or severe strains of potato spindle tuber viroid (PSTV) resulted in increased sensitivity to DAE under conditions of environmental stress. Leaves of chrysanthemum exhibiting DAE-induced chlorosis contained higher, but nontoxic, levels of iron and other minerals than those from non-DAE-treated plants. The importance of the presence of DAE in steam-treated growth media and steam-generated humidity is discussed.

The slab gel electrophoretic assay for detection and investigation of chrysanthemum chlorotic mottle viroid (CChMV) in infected plants

The slab gel electrophoretic assay for detection and investigation of chrysanthemum chlorotic mottle viroid (CChMV) in infected plants

Cross protection among four viroids

Cross-protection tests were performed on tomato and/or chrysanthemum plants with a severe strain (PS) of potato spindle tuber viroid (PSTV), a mild strain of PSTV (PM), citrus exocortis viroid (CEV), chrysanthemum stunt viroid (CSV), and chrysanthemum chlorotic mottle viroid (ChCMV). The identities of all viroids used, except ChCMV, were confirmed by fingerprinting the purified 125I-labeled RNAs. On tomato plants, PS and CEV caused identical, severe symptoms; PM caused mild symptoms; CSV replicated without causing symptoms; and replication of ChCMV could not be detected. Each viroid produced distinctive symptoms on chrysanthemum plants. On tomato, PM protected against the expression of symptoms by PS and CEV. On chrysanthemum, CSV, PM, and PS protected against CEV, but ChCMV did not protect against PS, CEV, or CSV; and PS failed to protect against ChCMV. In two cases of cross-protection, bioassays indicated that both the protecting and the challenge viroids had replicated. Thus, despite their different fingerprints (and hence RNA sequences), CEV, CSV, and two strains of PSTV affect a common biological process not affected by ChCMV.

Detection of a Latent Infectious Agent That Protects Against Infection by Chrysanthemum Chlorotic Mottle Viroid

Detection of a Latent Infectious Agent That Protects Against Infection by Chrysanthemum Chlorotic Mottle Viroid