Chrysanthemum Stunt Viroid

Abstract

The chrysanthemum stunt viroid (CSVd) is a small, single-stranded, infectious RNA forming a circular secondary structure, which belongs to the Pospiviroidae family and mainly infects certain species and cultivars of Compositae and Solanaceae. The effects on cultivated chrysanthemum are severe, including stunting of plant height, reduced flower size, and flower color bleaching. However, the expression of the symptoms depends on the chrysanthemum cultivars. CSVd is known to be readily transmitted by sap, but the infection rate and incubation period were observed to differ according to the varieties. Some CSVd-resistant cultivars have also been reported and the resistance is heritable in crosses between a CSVd-resistant chrysanthemum cultivar and CSVd-susceptible cultivars.

Invasion of shoot apical meristems by Chrysanthemum stunt viroid differs among Argyranthemum cultivars

“…CSVd has been included in the EPPO A2 list of quarantine pathogens ( OEPP/EPPO, 2014 ). CSVd infection causes various adverse effects on diseased Chrysanthemum plants including stunted growth, short internodes, poor root development, reduced flower size, and flower color bleaching, consequently resulting in the production of unmarketable plants and low yield of flowers ( Horst et al, 1977 ; Chung et al, 2001 ; Jeon et al, 2012 ; Matsushita, 2013 ; Savitri et al, 2013 ). Symptoms such as yellow deformed leaves with terminal necrosis, flower distortion, or leaf necrosis were observed on CSVd-infected Argyranthemum ‘Butterfly’ plants ( Marais et al, 2011 ).…”

Chrysanthemum Stunt Viroid Resistance in Chrysanthemum

“…One such disease is chrysanthemum stunt, incited by chrysanthemum stunt viroid (CSVd) [1,2,3]. Symptoms of a CSVd infection include stunting, spotted leaves, poor rooting, flower color change, and disturbance of photoperiodic responses related to flowering initiation [4,5,6,7,8,9]. The CSVd is a member of the genus Pospiviroid, within the family Pospiviroidae, which has a central conserved region and replicates and accumulates in the nuclei [10].…”

“…Recently, several studies have demonstrated the existence of resistance in commercial cultivars in Japan [21,22,23,24,25]. Since CSVd and infected plants are widely distributed, and a symptomless alternative host could be the source of the disease [8,26], chrysanthemum production has always been adversely affected by CSVd contamination. Consequently, CSVd resistance, which could withstand unforeseen contamination, would be a desirable trait.…”

Low Temperature Treatment Affects Concentration and Distribution of Chrysanthemum Stunt Viroid in Argyranthemum

“…Chrysanthemum stunt viroid (CSVd), a member of the family Pospiviroidae ( Bouwen and van Zaayen, 2003 ), can attack several ornamental crops, including Chrysanthemum ( Bouwen and van Zaayen, 2003 ), Argyranthemum ( Zhang et al, 2015 ), Dahlia ( Nakashima et al, 2007 ), and Petunia ( Verhoeven et al, 1998 ). Infection by CSVd can result in unmarketable plants and low yield of flowers ( Marais et al, 2011 ; Jeon et al, 2012 ; Matsushita, 2013 ; Savitri et al, 2013 ; Zhang et al, 2015 ), and possibly to considerable losses. CSVd is also listed as one of the quarantine pathogens in the European Union’s Plant Health Directive (2000/29/EC) ( Cho et al, 2013 ).…”