NMT历史上的今天丨AGR ECOSYST ENVIRON、Ecotoxicol Environ Saf 文章发表

2018年10月22日，福建农林大学林文雄、林生利用NMT在Agriculture, Ecosystems and Environment上发表了标题为Rhizosphere responses to environmental conditions in Radix pseudostellariae under continuous monoculture regimes的研究成果。

2018年10月22日，华中农业大学孙学成、史凯丽利用NMT在Ecotoxicology and Environmental Safety 上发表了标题为Non-invasive  microelectrode cadmium flux measurements reveal the decrease of cadmium  uptake by zinc supply in pakchoi root (Brassica chinensis L.)的研究成果。

期刊：Agriculture, Ecosystems and Environment

主题：连续单培养条件下假星豆根际对环境条件的响应

标题：Rhizosphere responses to environmental conditions in Radix pseudostellariae under continuous monoculture regimes

影响因子：3.541

检测指标：H+流速

作者：福建农林大学林文雄、林生

英文摘要

The root exudates of Radix pseudostellariae, working  as a rhizospheric intermediary between plants and microbes, can  deteriorate the microbial community in the rhizosphere in a consecutive  monoculture system.

We assessed the effects of artificially applied  R. pseudostellariae root exudates on R. pseudostellariae seedling  growth, rhizo-sphere soil microbial communities, and soil  physicochemical properties. We found that phenolic acids and or-ganic  acids acted as a driver of changes in the microbial community.  High-throughput sequencing and qRT-PCR analysis demonstrated that  treatment with phenolic acids significantly decreased the relative  abundance of Trichoderma, Penicillium, Pseudomonadales, Xanthomonadales,  and Streptomycetales.

Organic acids had a sig-nificant negative  effect on the relative abundance of Pseudomonadales and Streptomycetales  and significantly increased the abundance of Fusarium, Xanthomonadales,  Micrococcales, and Gemmatimonadales. Analysis based on the noninvasive  microtest technique indicated that root exudates increased H+ efflux and  plasma membrane H+-ATPase activity in the pathogenic fungi and decreased  them in the beneficial fungi.

These phenomena created an acidic  environment for the inhibition of beneficial bacteria and accumulation of  specialized plant pathogens. This study explains the mechanisms  underlying the shift in microflora and structural disorder caused by root  exudates in continuously monocultured R. pseudostellariae rhizosphere  soil through responses to en-vironmental conditions.

中文摘要（谷歌机翻）

在植物和微生物之间作为根际中介体工作的伪星根的根系分泌物会在连续的单培养系统中破坏根际微生物群落。

我们评估了人工施用的拟星果根分泌物对拟星果幼苗生长，根际土壤微生物群落和土壤理化特性的影响。我们发现酚酸和有机酸是微生物群落变化的驱动力。高通量测序和qRT-PCR分析表明，用酚酸处理可显着降低木霉菌，青霉菌，假单胞菌，黄单胞菌和链霉菌的相对丰度。

有机酸对假单胞菌和链霉菌的相对丰度有明显的负面影响，并显着增加了镰刀菌，黄单胞菌，微球藻和Gemmatimonadales的丰度。基于非侵入性微测试技术的分析表明，根系分泌物增加了病原真菌中的H  +流动和质膜H+ -ATPase活性，而减少了其有益真菌中的H+酶和质膜H+ -ATPase活性。

这些现象为抑制有益细菌和特殊植物病原体的积累创造了酸性环境。这项研究解释了通过对环境条件的响应，在连续单培养的假星菌根际土壤中根系分泌物引起的微孔和结构紊乱转变的潜在机制。

Fig. 7. Effect of Fusarium oxysporum on steady H+ fluxes  in R. pseudostellariae roots. CK represents roots without F. oxysporum  stimulation；F. oxysporum re-presents roots stimulated with F. oxysporum.

期刊：Ecotoxicology and Environmental Safety

主题：非侵入式微电极镉通量测量显示小菜根（甘蓝）中锌供应对镉吸收的减少

标题：Non-invasive microelectrode cadmium flux  measurements reveal the decrease of cadmium uptake by zinc supply in  pakchoi root (Brassica chinensis L.)

影响因子：3.974

检测指标：Cd2+流速

检测部位：小白菜根部（距离静止中心200um）

作者：华中农业大学孙学成、史凯丽

英文摘要

Zinc (Zn) possesses similar properties to cadmium  (Cd) and inhibits Cd uptake in plants. To get more detailed mechanisms  of Zn-inhibited Cd uptake in pakchoi, a hydroponic experiment was  conducted to investigate the effects of various Zn levels on Cd  concentrations, real time flux of Cd, expressions of genes related to Cd  uptake under Cd exposure.

The results showed that the Cd  concentrations and Cd accumulations in pakchoi root de-creased with  increasing Zn levels, which were coincident with that real time Cd influx  and net Cd influx of pakchoi root decreased with increasing Zn levels by  non-invasive micro-test technology (NMT). Additionally, the expressions  of Cd-related transporters including BcNRAMP5, BcIRT1 and BcMGT1  decreased with the increase of Zn levels under Cd exposure, especially  BcIRT1 with the highest decreased rates. Furthermore, the expressions of  these genes decreased gradually with the prolongation of Zn treated  time under Cd toxicity.

The results indicate that Zn inhibits Cd  uptake by inhibition of the expressions of Cd-related transporters,  especially BcIRT1 in pakchoi root.

中文摘要（谷歌机翻）

锌（Zn）具有与镉（Cd）相似的特性，并抑制植物中Cd的吸收。为了更详细地了解小白菜中Zn抑制Cd吸收的机理，进行了水培试验，研究了各种Zn水平对Cd浓度，Cd实时通量以及Cd暴露下与Cd吸收有关的基因表达的影响。

结果表明，通过无创微试验技术，小白菜根中的Cd浓度和Cd积累量随Zn水平的升高而降低，这与小菜根的实时Cd输入量和Cd净含量随Zn含量的增加而降低。   （NMT）。另外，随着镉暴露下锌水平的升高，包括BcNRAMP5，BcIRT1和BcMGT1在内的Cd相关转运蛋白的表达下降，尤其是下降率最高的BcIRT1。此外，随着镉对镉的毒害作用时间的延长，这些基因的表达逐渐降低。

结果表明，Zn通过抑制小白菜根中Cd相关转运蛋白特别是BcIRT1的表达来抑制Cd的吸收。

Fig. 3. Effects of Zn on net Cd2+ influxes in root of  pak-choi by Non-invasive micro-test technology. The 10 d pakchoi  seedlings treated with Zn deficiency Hoagland solution were used to  analyze the Cd influx. The Zn con-centrations of 0 (Zn 0), 1 (Zn 1), 5  (Zn 5) and 10 μM (Zn 10) represented that the concentrations of Zn were  added the basic solution containing 9 μM Cd. (A) The steady-state Cd2+  influx before and after the Zn supply into the basic solution. (B) Mean  rates of Cd2+ influx of the time in A. Each point represents the mean of  six roots from six in-dividual plants. Data are the means of 6  replicates ± standard error. Different lowercase represents significant  differences between treatments (p < 0.05).