金霉素添加对有机培肥土壤中磷循环微生物介导的磷素转化和有效性的影响  

Effects of chlortetracycline addition on phosphorus transformation and availability mediated by phosphorus cycling microorganisms in soil applied with organic fertilizer

作　　者：尹江琴 李佳颖 刘顺莉 谢小雨 陈新平 郎明 YIN Jiangqin;LI Jiaying;LIU Shunli;XIE Xiaoyu;CHEN Xinping;LANG Ming(Chongqing Key Laboratory of Efficient Utilization of Soil and Fertilizer Resources,College of Resources and Environment,Southwest University,Chongqing 400715,China;Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin,Southwest University,Chongqing 400715,China;Key laboratory of Low-carbon Green Agriculture in Southwestern,Southwest University,Chongqing 400715,China;Academy of Agricultural Sciences,Southwest University,Chongqing 400715,China)

机构地区：[1]西南大学资源环境学院,重庆市土肥资源高效利用重点实验室,重庆400715 [2]西南大学,长江经济带农业绿色发展研究中心,重庆400715 [3]西南大学,西南山地绿色低碳重点实验室,重庆400715 [4]西南大学,农业科学研究院,重庆400715

出　　处：《微生物学报》2024年第10期3980-3997,共18页Acta Microbiologica Sinica

基　　金：国家自然科学基金区域联合基金(U20A2047);国家自然科学基金(32272800,32002126);重庆市自然科学基金面上项目(CSTB2023NSCQ-MSX0507)。

摘　　要：【目的】探究不同浓度金霉素的添加对有机培肥土壤中参与无机磷溶解和有机磷矿化微生物群落特征及其介导的土壤磷素转化和有效性机制的影响。【方法】选取重庆市潼南区紫色土为基质土进行盆栽试验,外源添加有机肥(鸡粪),设置3个浓度的金霉素处理:不添加金霉素(0.0 mg/kg,No-CTC),低浓度金霉素(0.1 mg/kg,Low-CTC),高浓度金霉素(4.0 mg/kg,High-CTC)处理,在辣椒(‘辛香8号’)种植后第7天和第30天采集土样,利用Real-time qPCR、Illumina MiSeq高通量测序技术,结合基于生物有效性磷组分(biologically based phosphorus,BBP)的磷分级等方法,探究不同浓度金霉素添加对无机磷溶解和有机磷矿化关键基因(分别为pqqC和phoD基因)细菌的群落特征及其介导的土壤磷素转化机制的影响。【结果】在第7天仅高浓度金霉素处理增加了土壤Citrate-P和Enzyme-P含量,相对于未添加金霉素分别增加了8.2%和44.0%;高、低浓度金霉素处理在第30天均增加了Enzyme-P含量,相较于未添加金霉素处理分别增加了65.6%和44.0%。金霉素抑制了土壤碱性磷酸酶(alkaline phosphatase,ALP)活性,显著影响了含pqqC和phoD基因细菌的群落结构。基于Mantel检验结果表明,第7天Citrate-P与含pqqC基因的优势物种假单胞菌属(Pseudomonas)、地嗜皮菌属(Geodermatophilus)和糖丝菌属(Saccharothrix)显著相关,而含phoD基因的优势物种慢生根瘤菌属(Bradyrhizobium)、剑菌属(Ensifer)和斯克尔曼氏菌属(Skermanella)与Enzyme-P显著相关,随着处理时间的增加,其相关性均减弱。含pqqC基因细菌群落的网络平均度(average degree)在第7天低浓度金霉素处理时增加,高浓度时则降低,在第30天高、低浓度金霉素处理下其网络平均度均降低;然而,含phoD基因细菌群落的网络平均度在第7天随金霉素浓度增加而减弱,而第30天呈相反趋势。【结论】金霉素添加通过调控含pqqC和phoD基因细菌群落结构,�[Objective]To explore the effects of different concentrations of chlortetracycline on the characteristics of microbial communities involved in inorganic phosphorus(Pi)dissolution and organic phosphorus(Po)mineralization in the soil applied with organic fertilizer,focusing on soil P transformation and availability.[Methods]The purple soil collected from Tongnan District of Chongqing was used for a pot experiment with the addition of chicken manure as the organic fertilizer.Three chlortetracycline treatments(No-CTC,Low-CTC,and High-CTC)were designed with the addition levels of 0.0,0.1,and 4.0 mg/kg,respectively.The soil samples were collected on days 7(D7)and 30(D30)after pepper(‘Xinxiang 8')was planted.Real-time qPCR and Illumina MiSeq high-throughput sequencing were employed to analyze the community characteristics of the bacteria carrying the key genes(pqqC and phoD)of Pi dissolution and Po mineralization,respectively.Furthermore,the sequencing results and biologically based P(BBP)fractionation were employed to examine the effects of CTC addition on soil P transformation.[Results]High-CTC increased the content of Citrate-P and Enzyme-P by 8.2%and 44.0%,respectively,compared with No-CTC on D7.Low-CTC and High-CTC increased the content of Enzyme-P by 44.0%and 65.6%,respectively,compared with No-CTC on D30.The addition of CTC suppressed alkaline phosphatase(ALP)activity and affected the community structures of pqqC and phoD-harboring bacteria in the soil.The Mantel test results showed that Citrate-P was significantly associated with the dominant pqqC-carrying taxa Pseudomonas,Geodermatophilus,and Saccharothrix on D7.The dominant phoD-carrying taxa Bradyrhizobium,Ensifer,and Skermanella exhibited notable correlations with Enzyme-P on D7,and such correlations weakened over time.The average degree of the community network of the bacteria carrying pqqC increased in the Low-CTC treatment and decreased in the High-CTC treatment on D7.The average degree of this network decreased in High-CTC and Low-CTC treatments on D30

关 键 词：金霉素 有机培肥 pqqC基因 phoD基因 网络特征 有机磷矿化 无机磷溶解 

分 类 号：S154.3[农业科学—土壤学]