Kong Ping, Sharifi Melissa, Bordas Adria, Hong Chuanxue
Virginia Tech, Hampton Roads Agricultural Research and Extension Center, 1444 Diamond Springs Road, Virginia Beach, VA 23455, USA.
The Colonial Williamsburg Foundation, P.O. Box 1776, Williamsburg, VA 23185, USA.
Plants (Basel). 2021 Oct 21;10(11):2244. doi: 10.3390/plants10112244.
Isolated boxwood endophytes have been demonstrated to effectively protect boxwood plants from infection by (). However, the roles of endophytes as communities in plant defense are not clear. Here, we demonstrated differential tolerance to of English boxwood ( 'Suffruticosa'), an iconic landscape plant and generally regarded as highly susceptible, and its link to endophyte complexity. Fifteen boxwood twig samples were collected in triplicates from three historic gardens-Colonial Williamsburg, George Washington's Mount Vernon and River Farm, and Virginia Tech's research farm in Virginia Beach in the summer and fall of 2019. A portion of individual samples was inoculated with under controlled conditions. Significant differences in disease severity were observed among samples but not between the two seasons. Examining the endophyte cultures of the summer samples revealed that bacterial and fungal abundance was negatively and positively correlated with the disease severity. Nanopore metagenomics analysis on genomic DNA of the tolerant and susceptible group representatives confirmed the associations. Specifically, tolerant English boxwood plants had an endophyte community dominated by and , while susceptible ones had a distinct endophyte community dominated by , , and diverse fungi. These findings may lead to boxwood health management innovations-devising and utilizing cultural practices to manipulate and increase the abundance and performance of beneficial endophytes for enhanced boxwood resistance to .
已证明分离出的黄杨内生菌能有效保护黄杨植物免受（）感染。然而，内生菌作为群落在植物防御中的作用尚不清楚。在这里，我们展示了英国黄杨（‘Suffruticosa’），一种标志性的园林植物，通常被认为高度易感，对（）的不同耐受性，以及它与内生菌复杂性的联系。2019年夏秋两季，从三个历史花园——殖民地威廉斯堡、乔治·华盛顿的弗农山庄和河畔农场以及弗吉尼亚理工大学位于弗吉尼亚海滩的研究农场，采集了15份黄杨嫩枝样本，每份样本采集三份。在受控条件下，将一部分单个样本接种（）。样本之间观察到疾病严重程度存在显著差异，但两个季节之间没有差异。对夏季样本的内生菌培养物进行检查发现，细菌和真菌的丰度与疾病严重程度呈负相关和正相关。对耐受性和易感性组代表的基因组DNA进行纳米孔宏基因组学分析证实了这些关联。具体而言，耐受性英国黄杨植物的内生菌群落以（）和（）为主，而易感植物有一个以（）、（）和多种真菌为主的独特内生菌群落。这些发现可能会带来黄杨健康管理方面的创新——设计和利用栽培措施来操纵和增加有益内生菌的丰度和性能，以增强黄杨对（）的抗性。
