Department of Plant Pathology and Weed Research, Agricultural Research Organization, Volcani Institute, Rishon LeZion, Israel.
The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel.
Phytopathology. 2022 Nov;112(11):2296-2309. doi: 10.1094/PHYTO-03-22-0105-R. Epub 2022 Nov 30.
Diseases caused by the insect-transmitted bacterium have been reported in the Americas since the 19th century, causing diseases such as Pierce's disease of grapevine, almond leaf scorch (ALS), and citrus variegated chlorosis. In the last decade was reported from different parts of the world, most notably from southern Italy, infecting olives. In 2017, was reported to be associated with ALS symptoms in Israel. Here, we investigated the causal agent of ALS in Israel, its genetic diversity, and host range, and we characterized the temporal and spatial distribution of the disease. subsp. sequence type 1 was isolated from symptomatic almond trees and was used to infect almond and grapevine by mechanical inoculation. The pathogen, however, did not infect olive, peach, cherry, plum, nectarine, clementine, and grapefruit plants. Genomic analysis of local isolates revealed that the local population is derived from a single introduction and that they are closely related to strains from grapevines in California. Distribution analyses revealed that ALS did not expand from 2017 to 2019; however, since 2020, newly symptomatic trees appeared in the tested orchards. Symptomatic trees were located primarily in clusters, and symptoms tended to spread within rows. Our study confirms that is the causal agent of ALS in Israel and describes its genetic and host range characteristics. Although there is no clear evidence yet for the identity of the vectors in Israel, ALS spread continues to threat the almond and grapevine industries in Israel.
自 19 世纪以来，美洲就有昆虫传播细菌引起的疾病报告，这些疾病包括葡萄藤皮尔氏病、杏仁叶枯病 (ALS) 和柑橘斑驳黄化病。在过去十年中，该病已在世界不同地区报告，最著名的是意大利南部，感染橄榄树。2017 年，该病与以色列的 ALS 症状有关。在这里，我们研究了以色列 ALS 的病原体、其遗传多样性和宿主范围，并对该病的时空分布进行了特征描述。从症状性杏仁树上分离出的亚种 1 型被用作机械接种感染杏仁和葡萄的病原体。然而，该病原体不会感染橄榄、桃、樱桃、李、油桃、克莱门氏小柑橘和葡萄柚植物。对当地分离株的基因组分析表明，当地种群源自单一传入，与加利福尼亚葡萄藤上的菌株密切相关。分布分析表明，ALS 并未从 2017 年扩展到 2019 年；然而，自 2020 年以来，在测试的果园中出现了新的症状性树木。症状性树木主要位于簇中，症状在行间有扩散趋势。我们的研究证实，是以色列 ALS 的病原体，并描述了其遗传和宿主范围特征。尽管目前尚无以色列传播媒介身份的明确证据，但 ALS 的传播仍在继续威胁着以色列的杏仁和葡萄产业。
