Schloter M, Winkler J B, Aneja M, Koch N, Fleischmann F, Pritsch K, Heller W, Stich S, Grams T E E, Göttlein A, Matyssek R, Munch J C
Institute of Soil Ecology, GSF--National Research Center for Environment and Health, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
Plant Biol (Stuttg). 2005 Nov;7(6):728-36. doi: 10.1055/s-2005-872987.
Plant growth largely depends on microbial community structure and function in the rhizosphere. In turn, microbial communities in the rhizosphere rely on carbohydrates provided by the host plant. This paper presents the first study on ozone effects in the plant-rhizosphere-bulk soil system of 4-year-old beech trees using outdoor lysimeters as a research platform. The lysimeters were filled with homogenized soil from the corresponding horizons of a forest site, thus minimizing field heterogeneity. Four lysimeters were treated with ambient ozone (1 x O3) and four with double ambient ozone concentrations (2 x O3; restricted to 150 ppb). In contrast to senescence, which was almost unaffected by ozone treatment, both the photochemical quantum yield of photosystem II (PSII) and leaf gas exchange were reduced (11 - 45 %) under the elevated O3 regime. However, due to large variation between the plants, no statistically significant O3 effect was found. Even though the amount of primary metabolites, such as sugar and starch, was not influenced by elevated O3 concentrations, the reduced photosynthetic performance was reflected in leaf biochemistry in the form of a reduction in soluble phenolic metabolites. The rhizosphere microbial community also responded to the O3 treatment. Both community structure and function were affected, with a tendency towards a lower diversity and a significant reduction in the potential nutrient turnover. In contrast, litter degradation was unaffected by the fumigation, indicating that in situ microbial functionality of the bulk soil did not change.
植物生长很大程度上取决于根际微生物群落的结构和功能。反过来，根际微生物群落依赖于宿主植物提供的碳水化合物。本文以室外蒸渗仪为研究平台，首次对4年生山毛榉树的植物-根际-大土壤系统中的臭氧效应进行了研究。蒸渗仪中填充了来自森林场地相应土层的均质土壤，从而将田间异质性降至最低。四个蒸渗仪用环境臭氧（1倍O3）处理，四个用两倍环境臭氧浓度（2倍O3；限制在150 ppb）处理。与衰老几乎不受臭氧处理影响不同，在高O3条件下，光系统II（PSII）的光化学量子产率和叶片气体交换均降低（11%-45%）。然而，由于植物之间差异较大，未发现臭氧有统计学显著影响。尽管糖和淀粉等初级代谢产物的量不受高O3浓度影响，但光合性能的降低以可溶性酚类代谢产物减少的形式反映在叶片生物化学中。根际微生物群落也对臭氧处理有反应。群落结构和功能均受到影响，有多样性降低的趋势，潜在养分周转率显著降低。相比之下，凋落物降解不受熏蒸影响，表明大土壤的原位微生物功能没有变化。
