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<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>Kylle Roy</dc:contributor>
  <dc:contributor>Thomas C Harrington</dc:contributor>
  <dc:contributor>Eva Brill</dc:contributor>
  <dc:contributor>Lisa M Keith</dc:contributor>
  <dc:creator>Marc A Hughes</dc:creator>
  <dc:date>2023</dc:date>
  <dc:description>&lt;div class="abstract-group"&gt;&lt;div class="article-section__content en main"&gt;&lt;p&gt;&lt;i&gt;Metrosideros polymorpha&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;(‘ōhi‘a) trees in Hawaiʻi are dying from two distinct diseases, collectively referred to as rapid ‘ōhi‘a death (ROD), caused by&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;Ceratocystis lukuohia&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;and&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;Ceratocystis huliohia&lt;/i&gt;. Boring dust (frass) released when ambrosia beetles attack and colonize infected trees has been suspected as a transmission source. We sampled ambrosia beetle frass from six locations on Hawaiʻi Island and screened samples for&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;Ceratocystis&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;DNA and fungal viability.&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;Ceratocystis&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;DNA was detected in 79% of frass samples and 61% were viable. To assess the infectivity of&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;C&lt;/i&gt;.&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;lukuohia&lt;/i&gt;-colonized frass,&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;M&lt;/i&gt;.&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;polymorpha&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;seedlings were wound-inoculated with frass in growth chamber trials. Wilt incidence was 40% in the first trial and 15% in the second. Frass particles naturally infested with&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;C&lt;/i&gt;.&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;lukuohia&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;were treated with a cytoplasmic stain and microscopically examined; thick-walled chlamydospores were found in all samples. The chlamydospores appeared to be derived from aleurioconidia.&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;Ceratocystis&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;survival in frass was assessed in a baiting experiment conducted under varying environmental regimes; viability decreased with increasing temperature, frass age and decreasing humidity. After 6 months, 90% of the samples exhibited viable&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;C&lt;/i&gt;.&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;lukuohia&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;at the lowest temperatures. Results confirmed that&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;C&lt;/i&gt;.&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;lukuohia&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;chlamydospores are the fungal inoculum within ambrosia beetle frass and can induce wilt when introduced to&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;M&lt;/i&gt;.&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;polymorpha&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;wounds. Although ambrosia beetles or other insects may serve as vectors, the present work supports the hypothesis that&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;Ceratocystis&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;species may be dispersed in frass, which can inform ongoing efforts to manage ROD across Hawaiʻi's native forests.&lt;/p&gt;&lt;/div&gt;&lt;/div&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1111/ppa.13653</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>British Society for Plant Pathology</dc:publisher>
  <dc:title>Ceratocystis lukuohia-infested ambrosia beetle frass as inoculum for Ceratocystis wilt of ʻōhiʻa (Metrosideros polymorpha)</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>