生物炭对非常规水源灌溉下土壤-作物病原菌的影响

Effects of biochar supplementation on the behavior of pathogens in soil-plant System under unconventional water resources irrigation

采用根箱实验,基于定量PCR技术研究非常规水源(再生水和养殖废水)灌溉及生物炭添加后根际土、非根际土及玉米根部病原菌的赋存情况.结果发现,灌溉时间、土壤类型可显著影响土壤中病原菌的整体分布.相较于蒸馏水灌溉下根际土、非根际土的单个病原菌,再生水灌溉下病原菌变化为-0.74-0.17个数量级,养殖废水灌溉下为-0.14-0.60个数量级.生物炭对土壤中病原菌的影响因灌溉水源、灌溉时间而改变,可使再生水及养殖废水灌溉下病原菌检出量最高降低0.35、0.39个数量级.但再生水及养殖废水灌溉可使玉米根部病原菌检出量最高增加1.17、2.20个数量级,生物炭又使非常规水源灌溉下其检出量最高增加0.60、1.08个数量级,带来潜在的健康风险.

In the present study,the experiments were conducted in greenhouse rhizoboxes,to evaluate the overall pathogen status in rhizosphere and bulk soil,and the root endosphere of maize after unconventional water resources irrigation(reclaimed water and piggery wastewater)and biochar supplementation using quantitative PCR method.The results showed that the irrigation time and soil type could significantly influence the collected soil samples.Compared with individual pathogen in rhizosphere and bulk soil under distilled water irrigation,the variation caused by reclaimed water irrigation was-0.74-0.17orders,and the value was-0.14-0.60 orders caused by piggery wastewater irrigation.The effects of biochar supplementation varied with irrigation resources and time,with the maximum reduction values were 0.35,0.39 orders under the irrigation of reclaimed water and piggery wastewater.In addition,reclaimed water and piggery wastewater irrigation could increase pathogens in maize root by up to 1.17,2.20 orders,and biochar supplementation increased them by up to 0.60,1.08 orders,leading to potential health risks.