Promotion of growth and phytoextraction of cadmium and lead in Solanum nigrum L. mediated by plant-growth-promoting rhizobacteria
Promotion of growth and phytoextraction of cadmium and lead in Solanum nigrum L. mediated by plant-growth-promoting rhizobacteria
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DOI：
10.1016/j.ecoenv.2020.111333
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发表时间：
2020-12-01
影响因子：
6.8
通讯作者：
Xia, Yan
中科院分区：
文献类型：
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作者：
He, Xiaoman;Xu, Mingjing;Xia, Yan
植物根际促生菌（PGPR）是一类特殊的微生物，通过与植物根系的相互作用，促进植物生长，提高植物对金属胁迫的耐受性。评价了植物修复与镉积累植物龙葵（Solanum nigrum L.）和两种耐镉和铅的细菌分离物。为了了解PGPR与其宿主植物之间的相互作用，我们于2018年6月在南京农业大学（中国江苏省）进行了接种处理的温室实验。从重金属污染土壤中分离到两株具有不同促生特性的抗Cd和Pb的PGPR。经16 S rRNA序列分析表明，这两株菌均为芽孢杆菌属，分别命名为QX 8和QX 13。盆栽试验表明，接种能改善根际土壤环境，促进植物对铁、磷的吸收。接种QX 8和QX 13后，Cd和Pb污染土壤中植株地上部和根系的干重分别增加了1.36和1.7倍，地上部Cd和Pb含量分别增加了1.28-1.81倍和1.08-1.55倍。我们还检测到增加23%和22%的根际土壤酸性磷酸酶活性接种QX 8和QX 13，分别。然而，我们没有检测到接种和未接种处理的植物中的Cd和Pb的浓度和根际土壤中有效态Cd和Pb含量的显着差异。研究表明，PGPR辅助植物修复技术具有提高植物修复效率、改善土壤质量的潜力，是一种很有前途的重金属污染土壤修复技术。
Plant growth-promoting rhizobacteria (PGPR) are a specific category of microbes that improve plant growth and promote greater tolerance to metal stress through their interactions with plant roots. We evaluated the effects of phytoremediation combining the cadmium accumulator Solanum nigrum L. and two Cd- and Pb-resistant bacteria isolates. To understand the interaction between PGPR and their host plant, we conducted greenhouse experiments with inoculation treatments at Nanjing Agricultural University (Jiangsu Province, China), in June 2018. Two Cd- and Pb-resistant PGPR with various growth-promoting properties were isolated from heavy metal-contaminated soil. 16S rRNA analyses indicated that the two isolates were Bacillus genus, and they were named QX8 and QX13. Pot experiments demonstrated that inoculation may improve the rhizosphere soil environment and promote absorption of Fe and P by plants. Inoculation with QX8 and QX13 also enhanced the dry weight of shoots (1.36- and 1.7-fold, respectively) and roots (1.42- and 1.96-fold) of plants growing in Cd- and Pb-contaminated soil, and significantly increased total Cd (1.28-1.81 fold) and Pb (1.08-1.55 fold) content in aerial organs, compared to non-inoculated controls. We also detected increases of 23% and 22% in the acid phosphatase activity of rhizosphere soils inoculated with QX8 and QX13, respectively. However, we did not detect significant differences between inoculated and non-inoculated treatments in Cd and Pb concentrations in plants and available Cd and Pb content in rhizosphere soils. We demonstrated that PGPR-assisted phytoremediation is a promising technique for remediating heavy metal-contaminated soils, with the potential to enhance phytoremediation efficiency and improve soil quality.