Necrotic disorder of freesia (Freesia refracta hyb., Family Iridaceae) was first described in The Netherlands before 1970. In following years, the disorder was widely reported in other European countries including Northern Italy. Very recently, the same necrotic disease was also detected in Virginia (United States), New Zealand, Bulgaria and South Korea. Presence of the Ophiovirus Freesia sneak virus (FreSV) has been widely associated with the necrotic disease in every case but some uncertainty remains. The freesia leaf necrosis complex has been shown to be soil-borne, transmitted by Olpidium brassicae, but other infectious agents could be naturally transmitted by the same vector, thickening the plot about the disease causal agent. Freesia plants showing necrotic disease, collected in Northern Italy during the 2011-2012 growing season were used for virus purification procedures. The product obtained was used for total RNA extraction and for TEM visualization. Several differently shaped virus particles were visualized in the mixture and total RNA has been used for sequence-independent amplification for the identification of known and unknown RNA viruses infecting diseased freesia. Some significant results will be discussed.
The necrotic disease of freesia and viruses involved.
Vaira AM;Carra A;Vallino M;Lenzi R;
2014
Abstract
Necrotic disorder of freesia (Freesia refracta hyb., Family Iridaceae) was first described in The Netherlands before 1970. In following years, the disorder was widely reported in other European countries including Northern Italy. Very recently, the same necrotic disease was also detected in Virginia (United States), New Zealand, Bulgaria and South Korea. Presence of the Ophiovirus Freesia sneak virus (FreSV) has been widely associated with the necrotic disease in every case but some uncertainty remains. The freesia leaf necrosis complex has been shown to be soil-borne, transmitted by Olpidium brassicae, but other infectious agents could be naturally transmitted by the same vector, thickening the plot about the disease causal agent. Freesia plants showing necrotic disease, collected in Northern Italy during the 2011-2012 growing season were used for virus purification procedures. The product obtained was used for total RNA extraction and for TEM visualization. Several differently shaped virus particles were visualized in the mixture and total RNA has been used for sequence-independent amplification for the identification of known and unknown RNA viruses infecting diseased freesia. Some significant results will be discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
