<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">T. Jung</style></author><author><style face="normal" font="default" size="100%">Blaschke, H.</style></author><author><style face="normal" font="default" size="100%">W. Oßwald</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Involvement of soilborne Phytophthora species in Central European oak decline and the effect of site factors on the disease</style></title><secondary-title><style face="normal" font="default" size="100%">Plant Pathology</style></secondary-title><short-title><style face="normal" font="default" size="100%">Plant Pathology</style></short-title></titles><dates><year><style  face="normal" font="default" size="100%">2000</style></year><pub-dates><date><style  face="normal" font="default" size="100%">12/2000</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">49</style></volume><pages><style face="normal" font="default" size="100%">706 - 718</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;A survey was made on the occurrence of soilborne &lt;em&gt;Phytophthora&lt;/em&gt; species in 35 oak stands on a range of geologically different sites in Bavaria. The most widespread species were &lt;em&gt;P. quercina&lt;/em&gt;, &lt;em&gt;P. cambivora&lt;/em&gt; and &lt;em&gt;P. citricola&lt;/em&gt;. Seven other &lt;em&gt;Phytophthora&lt;/em&gt; species were isolated infrequently. The fine root systems of 106 healthy and 111 declining mature trees of &lt;em&gt;Quercus robur&lt;/em&gt; and &lt;em&gt;Q. petraea&lt;/em&gt; were intensively investigated. The results indicate that, depending on the site conditions, at least two different complex diseases are referred to under the name ‘oak decline’. On sites with a mean soil pH (CaCl&lt;sub&gt;2&lt;/sub&gt;) 3·5 and sandy-loamy to clayey soil texture &lt;em&gt;Phytophthora&lt;/em&gt; spp. were commonly isolated from rhizosphere soil, and highly significant correlations existed between crown transparency and various root parameters. Oaks with &lt;em&gt;P. quercina&lt;/em&gt; or other &lt;em&gt;Phytophthora&lt;/em&gt; spp. in their rhizosphere had markedly higher levels of fine root damage than oaks without &lt;em&gt;Phytophthora&lt;/em&gt; spp., and were subject to a relative risk of severe crown symptoms of 2·1 and 2·8, respectively. In contrast, in stands with sandy to sandy-loamy soils and a mean soil pH&amp;nbsp; 3·9, &lt;em&gt;Phytophthora&lt;/em&gt; spp. were not found. In these stands, correlations between crown transparency and various root parameters were either less significant or not significant. It is concluded that &lt;em&gt;Phytophthora&lt;/em&gt; species are strongly involved in oak decline on sandy-loamy to clayey sites with a mean soil-pH (CaCl&lt;sub&gt;2&lt;/sub&gt;).&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue></record></records></xml>