Salicylic acid and jasmonic acid signaling defense pathways reduce natural bacterial diversity on Arabidopsis thaliana
Salicylic acid and jasmonic acid signaling defense pathways reduce natural bacterial diversity on Arabidopsis thaliana
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DOI：
10.1094/mpmi-20-12-1512
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发表时间：
2007-12-01
影响因子：
3.5
通讯作者：
Bergelson, Joy
中科院分区：
文献类型：
--
作者：
Kniskern, Joel M.;Traw, M. Brian;Bergelson, Joy
陆生植物为各种各样的病原微生物和非病原微生物提供了巨大而多样的栖息地，但这些群落并没有得到很好的描述，而且对植物防御对自然界微生物群落的影响知之甚少。我们设计了一个田间实验，以确定两种植物防御信号通路的变化如何影响拟南芥天然内生和附生细菌群落的大小、多样性和组成。为此，我们在美国密歇根州西南部的一个种群中提供了这些细菌群落的初步特征，并在水杨酸（SA）和茉莉酸（JA）信号防御途径缺乏的拟南芥突变体、对照和人工提高防御水平的植物中比较了这两个群落。我们鉴定了30个不同的细菌类群，它们在菌落形态和16S rRNA序列上存在差异。我们发现，诱导sa介导的防御降低了内生细菌群落多样性，而缺乏ja介导的防御的植物则经历了更大的附生细菌多样性。群落总规模与多样性呈显著正相关，表明相对易感植物的细菌多样性较高。本实验为拟南芥上的细菌生态学提供了新的信息，并证明了两种特定植物信号防御途径的变化可以影响植物上的细菌多样性。
Terrestrial plants serve as large and diverse habitats for a wide range of pathogenic and nonpathogenic microbes, yet these communities are not well described and little is known about the effects of plant defense on microbial communities in nature. We designed a field experiment to determine how variation in two plant defense signaling pathways affects the size, diversity, and composition of the natural endophytic and epiphytic bacterial communities of Arabidopsis thaliana. To do this, we provide an initial characterization of these bacterial communities in one population in southwestern Michigan, United States, and we compare these two communities among A. thaliana mutants deficient in sallicylic acid (SA) and jasmonic acid (JA) signaling defense pathways, controls, and plants with artificially elevated levels of defense. We identified 30 distinct bacterial groups on A. thaliana that differ in colony morphology and 16S rRNA sequence. We show that induction of SA-mediated defenses reduced endophytic bacterial community diversity, whereas plants deficient in JA-mediated defenses experienced greater epiphytic bacterial diversity. Furthermore, there was a positive relationship between total community size and diversity, indicating that relatively susceptible plants should, in general, harbor higher bacterial diversity. This experiment provides novel information about the ecology of bacteria on A. thaliana and demonstrates that variation in two specific plant-signaling defense pathways can influence bacterial diversity on plants.