产碱菌Alcaligenes sp. qz-1对铬污染土壤中玉米生长和铬累积的影响研究

Effects of chromium(Ⅵ) tolerant bacteria Alcaligenes sp. qz-1 on growth and uptake of chromium(Ⅵ) in Maize Zea mays L.

通过盆栽试验研究了铬(Cr_2O_7^(2-))污染土壤中接种铬耐受细菌Alcaligenes sp. qz-1对玉米株高、茎粗、叶绿素含量、地上部分和地下部分干重以及铬含量的影响。结果表明,在重金属铬(Cr_2O_7^(2-))胁迫(50 mg·kg^(–1),100 mg·kg^(–1))下,玉米生长显著受到抑制(P<0.05)。与对照相比,株高分别减少9.92%和18.97%,茎粗分别降低了13.36%和14.24%,叶绿素含量分别降低了10.46%和13.25%。接种Alcaligenes sp. qz-1,可以显著缓解重金属胁迫对玉米生长的不利影响(P<0.05)。铬(Cr_2O_7^(2-))胁迫(50 mg·kg^(–1),100 mg·kg^(–1))下,接种Alcaligenes sp. qz-1的植株与未接种的玉米植株相比,株高分别增加了6.36%和10.91%,茎粗分别增加了10.17%和8.01%,叶绿素含量分别提高了9.16%和2.64%。同时,接种Alcaligenes sp. qz-1,可显著提高玉米(尤其是根系部分)对土壤铬的吸收量,吸收总量较未接种的增加13.9%—36.9%。综上所述,接种Alcaligenes sp. qz-1改善了铬(Cr_2O_7^(2-))胁迫下玉米生长特性,增加了玉米根部对铬(Cr_2O_7^(2-))的吸收,降低了铬(Cr_2O_7^(2-))对玉米的毒害,为该菌株进一步应用农田重金属污染进行治理提供一定理论依据和实践指导。

This paper studied the effects of inoculating chromium（Cr2O7^2-） tolerant bacteria Alcaligenes sp. qz-1 on the height, stem diameter, chlorophyll content, aerial part, underground dry weight as well as chromium contents in different parts of maize based on the pot experiments. The results showed that the growth of maize was inhibited under heavy metal chromium（Cr2O7^2-） stress（50 mg·kg^-1 and 100 mg·kg^-1）, the plant height was decreased by 9.92% and 18.97%, stem diameter was reduced by 13.36% and 14.24%, and chlorophyll content was reduced by 10.46% and 13.25% respectively. However, inoculation of Alcaligenes sp. qz-1 could significantly alleviate the adverse effects of heavy metal stress on Maize growth. Under heavy metal chromium（Cr2O7^2-） stress（50 mg·kg^-1 and 100 mg·kg^-1）, height of maize plants inoculated with Alcaligenes sp. qz-1 was increased by 6.36% and 10.91%, stem diameter was increased by 10.17% and 8.01%, and chlorophyll content was increased by 9.16% and 2.64% respectively when comparing with non-inoculated maize plants. At the same time, inoculation with Alcaligenes sp. qz-1 could obviously increase the uptake of chromium（Cr2O7^2-） by maize, and the total uptake increased by 13.9%-36.9% compared with non-inoculated plants. In summary, inoculation of Alcaligenes sp. qz-1 improved the growth characteristics of maize under the heavy metal chromium（Cr2O7^2-） stress, increased the uptake of chromium（Cr2O7^2-） in maize roots, and reduced the toxicity of chromium（Cr2O7^2-） to Maize. This study will provide theoretical basis and practical guidance for further application of Alcaligenes sp. qz-1 in heavy metal pollution in farmland.