{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,3]],"date-time":"2026-03-03T17:57:44Z","timestamp":1772560664774,"version":"3.50.1"},"reference-count":47,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,3,3]],"date-time":"2026-03-03T00:00:00Z","timestamp":1772496000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"Natural Science Foundation of China","doi-asserted-by":"publisher","award":["32472083"],"award-info":[{"award-number":["32472083"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Central Guidance Fund for Local Science and Technology Development","award":["2023ZYDF087"],"award-info":[{"award-number":["2023ZYDF087"]}]},{"name":"chief scientist innovation project of State Tobacco Monopoly Administration\/China National Tobacco Corporation","award":["702023CK0870"],"award-info":[{"award-number":["702023CK0870"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Plants"],"abstract":"<jats:p>Pine wilt disease (PWD), caused by Bursaphelenchus xylophilus, is a destructive forest disease leading to rapid mortality. Although Chongqing is a major epidemic region in China, the population genetic structure of B. xylophilus and the ecological interactions among nematode occurrence, blue stain formation, and microbial community dynamics remain insufficiently clear. This study systematically surveyed nematode incidence and performed morphological and molecular identification, revealing strong correlations between nematode presence, blue stain, and insect infestation (p &lt; 0.0001). Within Monochamus alternatus, nematodes were mainly distributed in the abdomen and thorax (p &lt; 0.0001). High-throughput sequencing showed significantly higher fungal (e.g., Leptographium) and bacterial (e.g., Burkholderia-Caballeronia-Paraburkholderia) diversity in diseased than healthy pinewood, indicating pronounced microbial shifts during disease progression. mtCOI-based genetic analyses of 162 nematodes from 11 populations revealed five haplotypes, with Hap1 shared across all populations. AMOVA indicated that over 80% of genetic variation occurred within populations, and neutrality and mismatch analyses suggested recent expansion in some populations (Beibei, Jiangbei, Rongchang). These findings clarify nematode epidemiology, microbial shifts, and genetic characteristics in Chongqing, providing a scientific basis for precise sampling, rapid detection, and integrated management of PWD, and suggest that microbial community changes may contribute to rapid pine decline.<\/jats:p>","DOI":"10.3390\/plants15050775","type":"journal-article","created":{"date-parts":[[2026,3,3]],"date-time":"2026-03-03T17:01:42Z","timestamp":1772557302000},"page":"775","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Investigation of Pine Wilt Disease in Chongqing: From Field Occurrence and Genetic Diversity to Endophytic Microbial Composition and Functional Analysis"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-7176-6625","authenticated-orcid":false,"given":"Haorong","family":"Yang","sequence":"first","affiliation":[{"name":"Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing 400716, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lan","family":"Jiang","sequence":"additional","affiliation":[{"name":"Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing 400716, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xu","family":"Hu","sequence":"additional","affiliation":[{"name":"Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing 400716, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shan","family":"Chen","sequence":"additional","affiliation":[{"name":"Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing 400716, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fan","family":"Jia","sequence":"additional","affiliation":[{"name":"Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing 400716, China"},{"name":"Agriculture Technology Extension Center of Wanrong County, Wanrong 044200, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7412-7790","authenticated-orcid":false,"given":"Guanhua","family":"Ma","sequence":"additional","affiliation":[{"name":"Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing 400716, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-9277-4694","authenticated-orcid":false,"given":"Kuo","family":"Huang","sequence":"additional","affiliation":[{"name":"College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ziqin","family":"Bai","sequence":"additional","affiliation":[{"name":"Fruit Research Institute, Guizhou Academy of Agricultural Sciences, Guiyang 550000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yang","family":"Zheng","sequence":"additional","affiliation":[{"name":"Institute of Vegetable and Flower Research, Chongqing Academy of Agricultural Sciences, Chongqing 400055, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-1859-7691","authenticated-orcid":false,"given":"Guokang","family":"Chen","sequence":"additional","affiliation":[{"name":"Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing 400716, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"198","DOI":"10.1007\/BF01086307","article-title":"Pine wilt toxin, the metabolite of a bacterium associated with a nematode","volume":"67","author":"Oku","year":"1980","journal-title":"Naturwissenschaften"},{"key":"ref_2","unstructured":"Kishi, Y. 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