富硒芽孢杆菌对赤红壤硒转化及菜心硒吸收累积的影响

【目的】研究不同富硒芽孢杆菌对富硒赤红壤硒形态、价态转化及菜心吸收累积硒的影响，为天然富硒蔬菜生产提供理论参考。【方法】以富硒赤红壤作为供试土壤、菜心作为供试作物，以2株富硒芽孢杆菌Bacillus cereus YLB1-6和Bacillus thuringiensis TXB2-5作为供试菌株，采用盆栽试验，以无菌...

Effects of selenium-rich bacillus on selenium transformation in lateritic red soil and selenium absorption and accumulation in Chinese flowering cabbage

【Objective】To investigate the effects of different selenium（Se）-rich bacillus on Se speciation，valence transformation in Se-rich lateritic soil and Se absorption and accumulation in Chinese flowering cabbage，so as to provide reference for natural Se-rich vegetable production.【Method】 Se-rich lateritic soil was used as tested soil and the Chinese flowering cabbage test crop.Two Se-rich Bacillus，Bacillus cereus YLB1-6 and Bacillus thuringiensis TXB2-5 were used as the test strains treated with different bacteria solutions and sterile water was taken as control（CK）.Pot experiment method was adopted.Se speciation，valences and pH of the soil samples collected after harvest，biomass of plants，Se content and Se accumulation in plant were measured.【Result】 Se-rich bacillus inoculation treatments promoted the transformation of residual Se（RES-Se）to different Se speciation，but there was some difference in Se speciation transformations in the soil by different bacillus.Available Se（AVA-Se）in soil treated with YLB1-6 and TXB2-5 was significantly increased（P<0.05，the same below），and it was mainly caused by the significant increase of soluble Se6+（SOL-Se6+）and exchangeable and carbonate-bound Se2-（EX-Se2-）contents.And contents of these two Se valences were significantly higher in YLB1-6 treatment than those in TXB2-5 treatment.YLB1-6 treatment significantly increased soil pH.Different Serich bacillus treatments had different effects on the Se absorption and accumulation of Chinese flowering cabbage.Both YLB1-6 and TXB2-5 treatments could significantly increase Se content in above-ground parts of Chinese flowering cabbage；Se content in below-ground parts of Chinese flowering cabbage in YLB1-6 treatment was similar to that of control，while TXB2-5 treatment significantly increased Se content in below-ground part of Chinese flowering cabbage.YLB1-6 treatment had a stronger ability to promote Se transfer to the above-ground parts of Chinese flowering cabbage.Se-rich bacillus inoculation had no obvious effect on biomass of Chinese flowering cabbage（P>0.05）.However，as the Se-rich bacillus treatments could significantly increase the Se contents in above-ground parts of Chinese flowering cabbage，Se accumulation of above-ground parts of the vegetable was also significantly increased.【Conclusion】Se-rich bacillus improves the soil AVA-Se content and promote the Se absorption and accumulation in soil of above-ground parts of Chinese flowering cabbage.B.cereus YLB1-6 has a better effect on promoting Se absorption of above-ground parts of the plant，showing a good potential for field application.