<?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%">Jeffers, S. N.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Enhancing detection of Phytophthora cactorum in naturally infested soil</style></title><secondary-title><style face="normal" font="default" size="100%">Phytopathology</style></secondary-title><short-title><style face="normal" font="default" size="100%">Phytopathology</style></short-title></titles><dates><year><style  face="normal" font="default" size="100%">1987</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1987</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">77</style></volume><pages><style face="normal" font="default" size="100%">1475</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Reliable methods were needed to detect &lt;em&gt;P. cactorum, &lt;/em&gt;one of the primary causal agents of &lt;em&gt;P. &lt;/em&gt;crown rot of apple trees, in its natural soil environment. Apple or pear fruits, used in a baiting bioassay, were ineffective at detecting &lt;em&gt;P. cactorum &lt;/em&gt;in naturally infested soil. Apple seedlings, cotyledons and seedling leaf pieces were successful baits, but cotyledons were the most sensitive and efficient. Completely air drying soil subsamples and then remoistening them for several days before flooding and adding plant tissue baits (extended baiting procedure) greatly enhanced detection when compared with the standard direct baiting procedure without prior manipulation of soil moisture. Bioassay incubation temp., volume of water added to remoisten air-dried soil subsamples, and incubation period following remoistening all affected detection, but the photoperiod during incubation did not. The advantages of an extended baiting bioassay with apple cotyledons were: greater sensitivity than with pear or apple fruits or by direct baiting, readily available and inexpensive baits, formation of sporangia of &lt;em&gt;P. cactorum &lt;/em&gt;directly on necrotic cotyledons, and lack of interference by contaminating &lt;em&gt;Pythium &lt;/em&gt;species. Cotyledons were also colonized by zoospores of &lt;em&gt;P. cambivora, P. citricola &lt;/em&gt;and &lt;em&gt;P. cryptogea, &lt;/em&gt;but not by those of &lt;em&gt;P. megasperma, P. syringae, P. drechsleri, &lt;/em&gt;or an unidentified &lt;em&gt;Phytophthora &lt;/em&gt;sp. The extended bioassay procedure routinely has provided a relatively rapid and efficient means of detecting &lt;em&gt;P. cactorum &lt;/em&gt;in a diversity of soils within and around New York apple orchards.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue></record></records></xml>