文摘
Replication and cellular movement of viroids are dependent on host plant components. Low temperatures reduce the physiological activity of host plants and thus suppress the levels of viroids. Chrysanthemum stunt viroid (CSVd) concentration was reduced in infected chrysanthemum (Chrysanthemum morifolium) plants subjected to low-temperature treatment compared with untreated plants. In this study, we investigated the distribution patterns of CSVd in the developing shoot tips of CSVd-infected chrysanthemum plants subjected to one-month, three-month, and six-month low-temperature treatment using in situ hybridization. After one month of low-temperature treatment, strong CSVd signals were detected in leaf primordia (LP) and the apical dome (AD); after three months, weak CSVd signals were detected in LP and the AD; while after six months, CSVd signals were not detected in LP or the AD, but only in tissues within the vascular bundle directly beneath viroid-free LP and AD areas. These changes in the distribution of CSVd in shoot tips subjected to low-temperature treatment might result from a reduction in viroid replication and/or the inhibition of viroid intra- and intercellular movement. Keywords Apical dome Callose deposition Chrysanthemum stunt viroid In situ hybridization Leaf primordia Shoot apical meristem