Chappell Lauren H K, Barker Guy C, Clarkson John P
Warwick Crop Centre, School of Life Sciences, Wellesbourne Campus, University of Warwick, Warwick CV35 9EF, UK.
J Fungi (Basel). 2024 Dec 16;10(12):873. doi: 10.3390/jof10120873.
Parsnips () are a speciality UK crop with an economic value of at least 31M GBP annually. Currently, the major constraints to production are losses associated with root canker disease due to a range of fungal pathogens, among which is of most concern to growers. With limited research conducted on this species, this work aimed to provide a much-needed characterisation of isolates from across the UK, continental Europe, and New Zealand. Previously, up to four separate species have been proposed based on the formation of chlamydospores and host specificity: , , , and . However, spp. isolates principally from parsnip, but also from a range of other hosts, which were found to infect both parsnip roots and leaves in pathogenicity tests. In growth rate assays, isolates were found to grow at temperatures of 0-25 °C and produce both chlamydospores and ballistospores across the same range of temperatures, although chlamydospore production was found to decrease as temperature increased. Following whole genome sequencing, specific primers were designed for the molecular characterisation of the isolates using six housekeeping genes and three highly variable functional genes. Phylogenetic analysis separated isolates into two and six clades, respectively, but the grouping was not associated with hosts or locations. Based on the results of this research, there was no evidence to support more than a single species of among the isolates studied.
欧洲防风（Parsnip）是英国的特色作物，每年经济价值至少为3100万英镑。目前，生产的主要限制因素是由一系列真菌病原体引起的根溃疡病造成的损失，其中[病原体名称未给出]是种植者最关注的。由于对该物种的研究有限，这项工作旨在对来自英国、欧洲大陆和新西兰的分离株进行急需的特征描述。此前，根据厚垣孢子的形成和寄主特异性，已提出多达四种不同的[病原体名称未给出]物种：[物种名称1]、[物种名称2]、[物种名称3]和[物种名称4]。然而，[病原体名称未给出]物种的分离株主要来自欧洲防风，但也来自一系列其他寄主，在致病性试验中发现它们会感染欧洲防风的根和叶。在生长速率测定中，发现分离株在0-25°C的温度下生长，并在相同温度范围内产生厚垣孢子和掷孢子，尽管发现厚垣孢子的产生随着温度升高而减少。在全基因组测序之后，使用六个管家基因和三个高度可变的功能基因设计了用于分离株分子特征描述的特异性引物。系统发育分析分别将分离株分为两个和六个进化枝，但分组与寄主或地点无关。基于这项研究的结果，在所研究的分离株中没有证据支持存在不止一种[病原体名称未给出]。
