Dees Merete Wiken, Lysøe Erik, Nordskog Berit, Brurberg May Bente
Bioforsk-Norwegian Institute for Agricultural and Environmental Research, Ås, Norway
Bioforsk-Norwegian Institute for Agricultural and Environmental Research, Ås, Norway.
Appl Environ Microbiol. 2015 Feb;81(4):1530-9. doi: 10.1128/AEM.03470-14. Epub 2014 Dec 19.
The phyllosphere is colonized by a wide variety of bacteria and fungi; it harbors epiphytes, as well as plant-pathogenic bacteria and even human pathogens. However, little is known about how the bacterial community composition on leafy greens develops over time. The bacterial community of the leafy-green phyllosphere obtained from two plantings of rocket salad (Diplotaxis tenuifolia) and three plantings of lettuce (Lactuca sativa) at two farms in Norway were profiled by an Illumina MiSeq-based approach. We found that the bacterial richness of the L. sativa samples was significantly greater shortly (3 weeks) after planting than at harvest (5 to 7 weeks after planting) for plantings 1 and 3 at both farms. For the second planting, the bacterial diversity remained consistent at the two sites. This suggests that the effect on bacterial colonization of leaves, at least in part must, be seasonally driven rather than driven solely by leaf maturity. The distribution of phyllosphere communities varied between D. tenuifolia and L. sativa at harvest. The variability between these species at the same location suggests that the leaf-dwelling bacteria are not only passive inhabitants but interact with the host, which shapes niches favoring the growth of particular taxa. This work contributes to our understanding of host plant-specific microbial community structures and shows how these communities change throughout plant development.
叶际被各种各样的细菌和真菌所占据；它包含附生植物，以及植物致病细菌甚至人类病原体。然而，关于绿叶蔬菜上的细菌群落组成如何随时间发展，我们知之甚少。通过基于Illumina MiSeq的方法，对从挪威两个农场的两次火箭沙拉（细叶双行芥）种植和三次生菜（生菜）种植中获得的绿叶蔬菜叶际细菌群落进行了分析。我们发现，对于两个农场的第1次和第3次种植，在种植后不久（3周），生菜样本的细菌丰富度显著高于收获时（种植后5至7周）。对于第二次种植，两个地点的细菌多样性保持一致。这表明，对叶片细菌定殖的影响，至少部分必须是受季节驱动，而不是仅由叶片成熟度驱动。收获时，细叶双行芥和生菜的叶际群落分布有所不同。同一地点这些物种之间的变异性表明，叶片上的细菌不仅是被动的居住者，而且与宿主相互作用，从而形成有利于特定分类群生长的生态位。这项工作有助于我们理解宿主植物特异性微生物群落结构，并展示了这些群落在植物发育过程中的变化。
