Distribution ofPotato spindle tuber viroidin New Zealand glasshouse crops of capsicum and tomato

Abstract

An initial investigation of Potato spindle tuber viroid (PSTVd) in capsicum revealed the presence of the viroid at two sites in the Auckland area. Subsequently, a delimiting survey of PSTVd was conducted in glasshouse capsicum and tomato crops in New Zealand from April to June 2002. The viroid was not detected in any of the 59 tomato sites surveyed. PSTVd was found at a further three of 41 capsicum sites surveyed in the Auckland region. Prior to the delimiting survey, three tomato sites where PSTVd was detected in April 2001 were visited and PSTVd was still present in tomato plants at one of these sites. Seeds and flesh from fruit of diseased capsicum and tomato plants tested PSTVd positive at two sites prior to the delimiting survey. The viroid was not detected in 8-, 16- and 27-week-old seedlings grown from seeds of infected capsicum and tomato crops. The PSTVd isolate from capsicum had 100% nucleotide identity to a tomato isolate from New Zealand (GenBank accession AF369530), 98.3% to a tomato isolate from the Netherlands (GenBank accession XI7268) and 96.3% to a Solanurn isolate from Australia (GenBank accession U51895). As PSTVd has never been reported in New Zealand before, capsicum and tomato seeds are considered to be the most likely source of PSTVd infection.