Co-Infection of Tobacco Rattle and Cycas Necrotic Stunt Viruses in : Detection Strategies, Potential Origins of Infection, and Implications for Germplasm Conservation.

Increasing reports of tobacco rattle virus (TRV) and cycas necrotic stunt virus (CNSV) in herbaceous worldwide highlight the importance of conserving the genetic resources of this economically important ornamental and medicinal crop. The unknown origin(s) of infection, differential susceptibility of peony cultivars to these viruses, and elusive disease phenotypes for CNSV in peonies make early detection and management challenging. Here, we report the presence of TRV and CNSV in plants of the University of Michigan living peony collection in the United States and a molecular characterization of their strains.

Population genetics of cycas necrotic stunt virus and the development of multiplex RT-PCR diagnostics.

Cycas necrotic stunt virus (CNSV) has an extensive host range and is detected in an accelerated pace around the globe in several agricultural crops. One of the plant species affected is peony (Paeonia lactiflora Pall.).

The population structure of the secovirid lychnis mottle virus based on the RNA2 coding sequences.

Lychnis mottle virus (LycMoV), family Secoviridae, is one of several viruses recently detected in peony. Given the high prevalence of the virus in the more than 300 samples tested, the population structure of the virus was studied using 48 isolates representing at least 20 cultivars and collected from major producing and propagating states in the United States. The homogeneity of the United States population, based on data from the RNA2 coding region, along with phylogenetic analyses of all publicly available sequences point to the dissemination of the virus through propagation material rather that active vector-mediated transmission.

Naturally occurring neuronal NO-synthase inactivators found in Nicotiana tabacum (Solanaceae) and other plants.

NO-synthase (NOS) is a heme-containing enzyme that catalyzes the oxidation of L-arginine to nitric oxide, an important cellular signaling molecule. Recently, it was found that aqueous extracts of tobacco cigarettes cause the inactivation of the neuronal isoform of NOS (nNOS) and that this may explain some of the toxicological effects of smoking. Although the exact identity of the chemical inactivator(s) is not known, we wondered if extracts prepared from other plants, including those closely related to tobacco, Nicotiana tabacum (Solanaceae), would similarly inactivate nNOS.