施用鸡粪有机肥对种植小油菜土壤微生物群落结构多样性的影响   总被引：4，自引：0，他引：4  

李可  孙彤  孙涛  徐应明  孙约兵 《农业环境科学学报》2020,39(10):2316-2324

为探究施用不同剂量的鸡粪有机肥对种植小油菜土壤微生物群落结构多样性的影响,设置0（CK）、7.5 t·hm^-2（T0.5）、15 t·hm^-2（T1）、30 t·hm^-2（T2）和60 t·hm^-2（T4） 5个鸡粪有机肥施用水平,种植3茬油菜后采集土壤样品,分析其基础化学性质和微生物磷脂脂肪酸（Phospholipid fatty acid,PLFA）组成特征,并探究微生物与土壤化学性质之间的关联。结果表明：施用鸡粪有机肥后,土壤肥力整体趋于升高,其中T4处理土壤有机质、全氮、全磷、全钾、硝态氮和有效磷含量分别较CK增加了34.1%、48.2%、47.9%、35.5%、3.9%和14.7%;土壤总PLFA、各类群微生物PLFA含量和真菌PLFA/细菌PLFA在中、高量有机肥处理下显著高于不施肥处理,T4处理总PLFA、细菌总PLFA和真菌总PLFA含量分别较CK增加了53.4%、52.1%和108.3%;T2处理的Shannon、Simpson、Pielou指数最高。微生物群落结构在施用极低和低剂量鸡粪有机肥（≤15 t·hm^-2）时较为相似,且显著区别于中量和高量施肥处理（≥30 t·hm^-2）;冗余分析结果表明,土壤基础化学特性解释了群落结构多样性发生变化的87.2%,起主要作用的环境因子包括硝态氮、总磷和pH,其中微生物PLFA与有效磷、铵态氮、硝态氮、全氮、全磷含量呈正相关,与土壤CEC和pH呈负相关。研究表明：施用鸡粪有机肥可以提高土壤肥力,增加土壤微生物群落多样性,但土壤微生物群落结构及多样性对不同的施肥剂量的响应结果不同,施用量为30 t·hm^-2和60 t·hm^-2时明显提高了土壤肥力、微生物总量及各菌群生物量,效果优于其他处理。因此,在短期内可通过适当增加有机肥的施用量来提高土壤肥力和生物学质量。  相似文献   

The isoelectric point, a key to understanding a variety of biochemical problems: a minireview     

Schuurmans Stekhoven FM  Gorissen MH  Flik G 《Fish physiology and biochemistry》2008,34(1):1-8

We address the importance of the isoelectric point (IEP) of proteins and membrane components such as phospholipids for our understanding and interpretation of isoforms and opposite charge interactions in the formation of complexes. Five examples drawn from the literature are newly approached from the IEP point of view to clarify general principles.  相似文献   

Exogenous polyunsaturated fatty acids (PUFAs) influence permeability,antimicrobial peptide resistance,biofilm formation and membrane phospholipid structure in an A-layer and non-A-layer strain of Aeromonas salmonicida     

Rachel N. Hofer  Allen Lin  Benjamin C. House  Christopher N. Purvis  Bradley J. Harris  Steven J. K. Symes  David K. Giles 《Journal of fish diseases》2023,46(1):31-45

Aeromonas salmonicida is a Gram-negative bacterium that can infect a wide host range of fish populations, including salmonids and non-salmonids as well as freshwater and marine life. Some strains of A. salmonicida cause the disease furunculosis, which can cause lethargy, intestinal inflammation, ulcers, haemorrhaging and death. The infection is spread through fish-to-fish contact, and the presence of infection can have devastating effects on cultivated fish populations. The purpose of this study was to explore the ability of non-A-layer and A-layer A. salmonicida strains to incorporate polyunsaturated fatty acids (PUFAs) into their lipid profile and test the phenotypic effects thereof. Lipids were extracted from PUFA-exposed cultures and analysed for lipid modification by thin-layer chromatography and ultraperformance liquid chromatography-mass spectrometry, showing A. salmonicida, regardless of A-layer, capable of incorporating all seven of the PUFAs studied. Phenotypic effects were determined through the use of assays that tested for biofilm formation, membrane permeability and cyclic peptide susceptibility. Temperature-dependent effects on biofilm formation were observed, and PUFA exposure showed significant (p < .001) increases in membrane permeability as tested by the uptake of the hydrophobic compounds crystal violet and ethidium bromide. Additionally, some PUFAs elicited modest protection and vulnerability against the membrane-targeting cyclic peptides polymyxin B (PMB) and colistin. The diverse, strain-specific responses to exogenous PUFAs may allude to evolved adaptive strategies that enhance survival, persistence and virulence of non-pathogenic and pathogenic members of bacteria that oscillate between environmental and fish host niches.  相似文献   

黄油乳清组分分析与乳化特性评价     

张雁斌  吴珊  李芷茜  罗洁 《农业机械学报》2023,54(11):412-420

黄油乳清(BS)是生产无水黄油时产生的副产物。由于富含乳脂肪球膜等组分，黄油乳清被认为是富集球膜组分的良好原料。然而，目前的研究集中于黄油乳清的基础组分构成，对脂肪球膜源组分的构成及应用特性的研究尚未明确，限制了黄油乳清的应用。通过离心搅打等方式从牛乳黄油中分离出黄油乳清，以原料乳和酪乳为对照，分析了黄油乳清的基本组分和脂肪球膜源组分构成。结果表明，与原料乳、酪乳相比，黄油乳清的蛋白质、脂肪质量分数显著增加，总钙含量显著降低，乳糖质量分数、含水率、pH值等无显著性差异(P>0.05);黄油乳清中含脂肪球膜磷脂56种，包括磷脂酰胆碱(Phosphatidylcholine, PC)20种、磷脂酰乙醇胺(Phosphatidylethanolamine, PE) 10种、磷脂酰丝氨酸(Phosphatidylserine, PS)7种、磷脂酰肌醇(Phosphatidylinositol, PI)6种、鞘磷脂(Sphingomyelin, SM)13种，其中鞘磷脂含量约为酪乳的3倍，质量浓度达到0.352 mg/mL;黄油乳清含脂肪球膜蛋白4种，其中丰度最大的为高碘酸希夫糖蛋白6/7...  相似文献