Plant tissues host complex fungal and bacterial communities, and their composition is determined by host traits such as tissue age, plant genotype and environmental conditions. Despite the importance of bark as a possible reservoir of plant pathogenic microorganisms, little is known about the associated microbial communities. In this work, we evaluated the composition of fungal and bacterial communities in the pear (Abate and Williams cultivars) and apple (Golden Delicious and Gala cultivars) bark of three/four-year-old shoots (old bark) or one-year-old shoots (young bark), using a meta-barcoding approach. The results showed that both fungal and bacterial communities are dominated by genera with ubiquitous attitudes, such as Aureobasidium, Cryptococcus, Deinococcus and Hymenobacter, indicating intense microbial migration to surrounding environments. The shoot age, plant species and plant cultivar influenced the composition of bark fungal and bacterial communities. In particular, bark communities included potential biocontrol agents that could maintain an equilibrium with potential plant pathogens. The abundance of fungal (e.g. Alternaria, Penicillium, Rosellinia, Stemphylium and Taphrina) and bacterial (e.g. Curtobacterium and Pseudomonas) plant pathogens was affected by bark age and host genotype, as well as those of fungal genera (e.g. Arthrinium, Aureobasidium, Rhodotorula, Sporobolomyces) and bacterial genera (e.g. Bacillus, Brevibacillus, Methylobacterium, Sphingomonas and Stenotrophomonas) with possible biocontrol and plant growth promotion properties.

植物组织具有复杂的真菌和细菌群落，其组成取决于宿主的性状，例如组织年龄，植物基因型和环境条件。尽管树皮作为植物病原性微生物的可能贮藏库的重要性，但对相关的微生物群落知之甚少。在这项工作中，我们评估了三岁或四岁新芽（旧树皮）或一年新芽的梨（Abate和Williams品种）和苹果（金冠和Gala品种）树皮中真菌和细菌群落的组成。使用元条形码方法处理旧芽（年轻的树皮）。结果表明，真菌和细菌群落都以普遍存在的态度为主，如金黄色杆菌属，隐球菌，灭球菌。和处女膜，表明微生物向周围环境强烈迁移。芽龄，植物种类和植物品种影响树皮真菌和细菌群落的组成。特别是，树皮群落包括可能与潜在植物病原体保持平衡的潜在生物防治剂。真菌的丰度（如赤，青，Rosellinia，匍柄和Taphrina）和细菌（如Curtobacterium属和假单胞菌（例如）植物病原体是受树皮年龄和主机基因型，以及那些真菌属的节菱，出芽短梗，红酵母，掷孢酵母）和细菌属（如芽孢杆菌，短短芽孢，Methylobacterium，鞘氨醇及嗜）与可能的生物防治和促进植物生长的特性。