Witzell Johanna, Sunnerstam Caroline, Hansson Tobias
Department of Forestry and Wood Technology, Linnaeus University, Georg Lückligs väg 1, 35195 Växjö, Sweden.
J Fungi (Basel). 2023 Feb 24;9(3):297. doi: 10.3390/jof9030297.
Dutch elm disease (DED) is causing extensive mortality of ecologically and culturally valuable elm trees ( spp.). Treatment of elms with the biological vaccine Dutch Trig has been found to provide effective protection against DED by stimulating the defensive mechanisms of the trees. We hypothesized that the same mechanisms could also affect non-target organisms associated with elms. We explored the possible effects of vaccination on epiphytes (mainly lichens) and fungal endophytes living in the bark and young xylem of treated elms. Epiphyte cover percentage was assessed visually using a grid placed on the trunks, and a culture-based approach was used to study endophytes. Epiphyte cover was lower on the trunks of vaccinated trees as compared with unvaccinated trees, but the difference was not statistically significant. The presence of slow-growing and uncommon endophytes seemed to be reduced in continuously vaccinated elms; however, the highest endophyte diversity was found in elms four years after cessation of the vaccination treatments. Our findings suggest that although vaccination may shape epiphyte and endophyte communities in elms, its impacts are not straightforward. More detailed studies are, therefore, needed to inform the sustainable application of the vaccine as a part of the integrated management of DED.
荷兰榆树病（DED）正在导致具有生态和文化价值的榆树（榆属树种）大量死亡。已发现用生物疫苗荷兰三角剂处理榆树可通过刺激树木的防御机制来有效预防荷兰榆树病。我们推测相同的机制也可能影响与榆树相关的非靶标生物。我们探究了接种疫苗对生活在经处理榆树树皮和幼嫩木质部中的附生植物（主要是地衣）和真菌内生菌的可能影响。使用放置在树干上的网格目视评估附生植物的覆盖百分比，并采用基于培养的方法研究内生菌。与未接种疫苗的树木相比，接种疫苗树木树干上的附生植物覆盖度较低，但差异无统计学意义。在持续接种疫苗的榆树中，生长缓慢且不常见的内生菌的存在似乎有所减少；然而，在停止疫苗接种处理四年后的榆树中发现了最高的内生菌多样性。我们的研究结果表明，尽管接种疫苗可能会塑造榆树中的附生植物和内生菌群落，但其影响并非直接明了。因此，需要进行更详细的研究，以便为将该疫苗作为荷兰榆树病综合管理的一部分进行可持续应用提供依据。
