微生物共生对拟南芥抗干旱发育的基因表达调控

Microbial symbiosis is an important way for plant to adapt to the environment. Microorganisms enhance plant tolerance to adversity by participating in / regulating host gene expression. Our previous study has found that inoculating endophytic bacteria which was isolated from the desert plant Lepidium perfoliatum L. could increase the number of seed pods, the number of seeds and seed weight of Arabidopsis. Under drought stress condition, inoculating endophytic bacteria could also increase the number of seed pods and yield. Besides, inoculating endophytic bacteria make flower earlier 2-4 days but did not affect the germination rate of the next generation. In order to study the genetic regulation of symbiotic microbes to Arabidopsis, this study were carrying out by inoculating effective isolates to Arabidopsis seedlings, detecting the biological response of Arabidopsis to exogenous microorganisms by traditional techniques under non-stressed and drought-stressed conditions, analyzing the genes involved in plant stress tolerance with endophytic bacteria by transcriptome analysis, detecting the expression level of key genes with quantitative PCR. The mechanism of symbiotic microorganisms on the growth and development of model plants under drought condition was explored in molecular level. This study will provide the basis for enriching the biological theory, exploiting microbial resources and developing reversible agriculture.

植物与微生物共生是植物适应环境的重要方式，微生物通过参与/调节宿主基因表达增强其逆境耐受性。前期研究发现接种分离自荒漠短命植物抱茎独行菜的内生细菌的培养物可增加拟南芥每株果荚数、种子数、种子重量。在干旱胁迫下，接种内生细菌的植株的每果荚种子数，每株果荚数及产量比未接种的对照组多，成熟期则缩短2-4天但不影响子代萌发率。为了研究共生微生物在干旱胁迫下对拟南芥基因表达的调控，本项目以具有显著促生效果的菌株接种拟南芥幼苗，以传统技术检测干旱胁迫下拟南芥对外源微生物的生物学响应，以转录组分析微生物对拟南芥抗逆与发育的基因调控，以定量PCR检测关键基因的表达，从分子水平探索干旱条件下共生微生物对模式植物生长发育的调控机制，为丰富生物学理论、开发微生物资源和发展抗逆农业提供依据。

植物与微生物共生是植物适应环境的重要方式，微生物通过参与/调节宿主基因表达增强其逆境耐受性。研究中我们将从荒漠短命植物抱茎独行菜中分离得到的60多株细菌分别接种模式植物拟南芥，观察在正常和干旱胁迫情况下，接种组在抽薹、株高、叶片叶绿素含量、相对含水量、种子产量等的变化。结果表明，在正常和干旱胁迫下，接种组在抽薹、株高、叶绿素含量、相对含水量、种子产量等比对照组高，但只有部分分离株在叶绿素含量、相对含水量、种子产量等方面表现差异显著，其余皆表现差异不显著。我们拟将对接种菌明显积极响应的拟南芥，进行转录组测序，进而分析共生与生长发育、抗旱等基因调控关系，以筛选共调控基因并分析调控因子，从分子水平探索正常及干旱条件下共生微生物对模式植物生长发育的调控机制，为丰富生物学理论、开发微生物资源和发展抗逆农业提供依据。