Improved grain yield and lowered arsenic accumulation in rice plants by inoculation with arsenite-oxidizing Achromobacter xylosoxidans GD03
Improved grain yield and lowered arsenic accumulation in rice plants by inoculation with arsenite-oxidizing Achromobacter xylosoxidans GD03
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通过接种亚砷酸氧化木糖氧化无色杆菌 GD03 提高水稻产量并降低砷积累
DOI：
10.1016/j.ecoenv.2020.111229
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发表时间：
2020
影响因子：
6.8
通讯作者：
Yang GuiDi
中科院分区：
文献类型：
--
作者：
Wang KaiTeng;Li YuanPing;Wu YongChen;Qiu ZongQing;Ding ZhenXi;Wang XingJu;Chen Wei;Wang RenJie;Fu FengFu;Rensing Christopher;Yang GuiDi
亚砷酸盐是水稻淹水土壤中的主要砷种，亚砷酸盐在水稻颗粒中的生物积累已成为许多亚洲国家面临的主要问题。通过加速亚砷酸盐氧化来降低水稻植株和谷物中的亚砷酸盐水平，是帮助依赖大米消费的人群减少体内砷暴露水平的一种潜在策略。本研究分离到一株具有高亚砷酸氧化能力和促进植物生长特性的无色杆菌（Achromobacter xylosoxidansGD03）。我们观察到接触亚砷酸盐可以促进tea。木糖氧化物使gd03分泌吲哚-3-乙酸，从而促进水稻生长。籼稻品种光优明118 （GYM118）盆栽试验表明：接种水田土（4.5 ~ 180 × 108CFU GD03/kg土）显著加速了淹水土壤中亚砷酸盐的氧化。在原生菌群存在的情况下，接种GD03菌株的籼稻GYM118全生育期日砷氧化速率是未接种GD03菌株的1.5 ~ 3.3倍。使籼稻GYM118茎、叶、糠和籽粒亚砷酸盐浓度分别降低34-69%、43-74%、24-76%和35-57%，籽粒产量提高59-96%。水稻土接种剂量为40.0 mL/kg。木糖氧化物GD03对籼稻GYM118各器官的As（III）浓度最低，仅相当于未接种GD03组的24-50%。结果表明，高亚砷氧化菌在与原生菌群竞争时，可加速水稻土的亚砷氧化，从而降低砷毒性和生物可利用性土壤砷。
Arsenite is the predominant arsenic species in flooded paddy soil, and arsenite bioaccumulation in rice grains has been identified as a major problem in many Asian countries. Lowering arsenite level in rice plants and grain via accelerating arsenite oxidation is a potential strategy to help populations, who depended on rice consumption, to reduce the internal exposure level of arsenic. We herein isolated a strain,Achromobacter xylosoxidansGD03, with the high arsenite-oxidizing ability and plant growth-promoting traits. We observed that arsenite exposure could promoteA. xylosoxidansGD03 to excrete indole-3-acetic acid and thus promoted rice growth. The pot culture experiments of Indica rice cultivar Guang You Ming 118 (GYM118) demonstrated thatA. xylosoxidansGD03 inoculation of paddy soil (4.5–180 × 108CFU GD03/kg soil) significantly accelerated arsenite oxidation in flooded soil. The daily arsenic oxidation rate with GD03 inoculation was 1.5–3.3 times as that without strain GD03 inoculation within the whole growth period of Indica GYM118 in the presence of the native microflora. It thus led to a 34–69%, 43–74%, 24–76% and 35–57% decrease in arsenite concentration of the stems, leaves, bran and grain of Indica GYM118 respectively and a 59–96% increase in rice grain yield. The paddy soil inoculated with 40.0 mL/kg ofA. xylosoxidansGD03 resulted in a lowest As(III) concentrations in all rice organs of Indica GYM118, which equivalent to only 24–50% of the As(III) concentrations in the group without GD03 inoculation. The results highlight that a highly arsenite-oxidizing bacterium could accelerate arsenite oxidation of paddy soil when facing competition with the native microflora, thus decrease arsenic toxicity and bioavailable soil arsenic.