水稻根分泌物及其与粪产碱菌的相互作用   总被引：9，自引：0，他引：9  

林敏  尤崇杓 《中国农业科学》1989,22(6):6-12

水稻植株通过根系向根际分泌多种有机酸、糖、氨基酸和植物激素。平均每克鲜根分泌有机酸2.25mg,柠檬酸含量较高,其次是苹果酸、琥珀酸、乳酸;氨基酸2.61mg,大约有15种,碱性氨基酸含量最高;糖12.6mg,以蔗糖、葡萄糖、果糖为主;植物激素仅测到赤霉酸（GA#-3）。不同水稻品种的根分泌物在组成及含量上都有差异。粪产碱菌在纯培养条件下能分泌9种氨基酸,一种有机酸即苹果酸以及植物激素如生长素（IAA）、赤霉酸（GA#-3）,但不分泌糖。接种粪产碱菌能刺激水稻根的分泌作用,并对根分泌物的组成和含量有所影响。2.63%的水稻光合产物以根分泌物形式释放到根区,接种粪产碱菌后分泌量增至3.52%,并且大部分为粪产碱菌吸收利用。水稻的光合作用及根分泌能力影响根际固氮活性。具有较强分泌能力的植株,其根际固氮活性也较高。  相似文献   

粪肠球菌对吉富罗非鱼的生长、体组成、消化酶活性及血液生理生化指标的影响     

黄旺  李洪琴  罗莉  陈拥军  白富瑾  林肯 《水产学报》2017,41(11):1756-1765

为研究饲料中添加不同浓度的粪肠球菌对吉富罗非鱼生长、体组成、消化能力及血液生理生化指标的影响,实验选用初始体质量为(50.59±0.59)g的吉富罗非鱼300尾,随机分成5组,每组设3个重复,每个重复20尾鱼,养殖实验期60 d。分别投喂实测含1.3×10~2(对照组)、1.4×10~5、1.7×10~6、1.5×10~7和1.8×10~8 CFU/g粪肠球菌的5种等氮(36%)等脂(6.75%)的实验饲料。结果显示:(1)罗非鱼的末均重(FBW)、增重率(WGR)、特定生长率(SGR)和尾均摄食量(FI)均在1.5×10~7 CFU/g组达到最大且显著高于对照组,而饲料系数(FCR)显著低于对照组。以FBW、WGR和SGR为评价指标,通过二次回归分析得出,罗非鱼饲料的粪肠球菌适宜添加浓度范围为7.5×10~7~1.1×10~8 CFU/g。(2)各添加组的全鱼粗蛋白含量均显著高于对照组,1.5×10~7 CFU/g组的粗脂肪含量显著高于对照组,各组间全鱼水分和粗灰分含量无显著差异。1.5×10~7 CFU/g组的干物质、蛋白质和脂肪沉积率均达到最大值且显著高于对照组。(3)1.5×10~7和1.8×10~8 CFU/g组的肠脂肪酶活性均显著高于对照组,而1.8×10~8 CFU/g组的肠道蛋白酶活性显著低于对照组;各组间肠道淀粉酶活性无显著差异。(4)1.5×10~7 CFU/g组的平均红细胞体积、血红蛋白浓度和血小板数均显著低于对照组,各组间红细胞数无显著差异。(5)1.8×10~8 CFU/g组的血清中胆固醇、葡萄糖和丙二醛含量显著低于对照组;1.5×10~7 CFU/g组血清中碱性磷酸酶活性显著高于对照组,而谷丙转氨酶和谷草转氨酶活性显著低于对照组。综上所述,吉富罗非鱼(50~210 g)饲料中粪肠球菌的适宜添加浓度范围为7.5×10~7~1.1×10~8 CFU/g,但添加粪肠球菌对血液载氧能力有负面影响。  相似文献   

Dietary supplement of Enterococcus faecalis on digestive enzyme activities,short‐chain fatty acid production,immune system response and disease resistance of Javanese carp (Puntius gonionotus,Bleeker 1850)          下载免费PDF全文

S. K. Allameh  E. Ringø  F. M. Yusoff  H. M. Daud  A. Ideris 《Aquaculture Nutrition》2017,23(2):331-338

This study investigated the effects of Enterococcus faecalis on digestive enzyme activities and short‐chain fatty acid production in fish intestine, resistance against Aeromonas hydrophila and humoral immunity response by 3 experiments on Javanes carp (Puntius gonionotus). The experiment 1 revealed that diet supplemented with E. faecalis significantly (P < 0.05) increased protease and lipase activities compared to control fed fish. Moreover, E. faecalis supplementation significantly enhanced the production of propionic and butyric acid in the intestine, while no significant difference (P > 0.05) in acetic acid production was observed. In the challenge study (experiment 2), fish were injected (intraperitoneal) with 10⁷ A. hydrophila per ml and survival was significantly improved when fish were fed diet supplemented with E. faecalis compared to control fish. In experiment 3, dietary E. faecalis affected immune system response as fish fed the probiont and exposed to 10⁶ A. hydrophila per ml displayed significantly elevated antibody levels compared to control fed fish. Fish fed diet supplemented with E. faecalis but not exposed to the pathogen revealed significantly higher antibody level than control fish (P < 0.05). Therefore, E. faecalis can be used as a probiotic in Javanese carp farming.  相似文献   

The Influence of Shock Treatment on Survival Rate of Intestinal Probiotics during Freezing     

LI Chun ZHANG Lanwei LIU Libo FENG Zhen 《东北农业大学学报(英文版)》2006,13(1):36-40

Probiotics which can provide potential health benefits for consumers and prevent disease, is the most important research field for functional food in the future. It is the key point that how much the count of bacteria and how long it can preserve. Freeze-drying skill is one of the best preservation methods, but it's defect that damage to biological systems can be attributed to changes in the physical state of membrane lipids or/and changes in the structure of sensitive proteins and the decreased survival rate. This work used pretreatment methods-cold shock and hot shock to reduce the damage to bacteria during freeze-drying. Using unpretreated samples as control, aspects of cold shock or heat shock. The response of Enterococcous faecalis A31 was investigated during lag phase, the middle of exponential growth phase and the terminal of exponential growth phase. The results suggested that when cold shock, the shock protein concentration produced by treated sample within 2 h during the middle of exponential growth phase was higher than 4, 8, 24 h, The concentration of shock protein produced by treated sample at 10 ℃ was higher than 20℃, The concentration of sample protein at the middle of exponential growth phase was higher than that at the terminal of exponential growth phase. After one-month storage, the survival rate at 10℃ was better than 20 ℃ and 4 ℃ comparatively. The survival rate at (6 h) 4 ℃/24 h (lag period) was higher than (10 h) 4 ℃/24 h (the middle of exponential growth phase), and the effect of 10 ℃ /8 h shock treatments was best during the middle of exponential growth phase, when hot shock, The concentration of heat shock proteins produced was not obvious, and survival rate was higher at 45℃, 30 min than at 45 ℃, 60 min.  相似文献   

宠物源菌株的分离鉴定及耐药性分析     

郭泽宇  邢家宝  马庆磊  马丹倩  秦盼盼  李露  李跃  赵文超  刘建华 《现代畜牧兽医》2020,(2):14-19

为了解河南郑州市常见宠物携带菌株组成以及耐药情况,本试验采集了郑州地区不同宠物医院患病及健康犬、猫共计76个样本的肛拭子、眼拭子、耳拭子。试验通过细菌分离培养、形态学观察、生化试验、16s rRNA基因测序完成细菌鉴定,确定分离菌株种类,采用微量肉汤稀释法测定分离菌株耐药表型。结果共分离得到大肠杆菌50株、肠球菌27株、奇异变形杆菌24株、葡萄球菌46株、绿脓杆菌4株。奇异变形杆菌耐药最为严重,对多西环素、替米考星两种药物耐药率高于90.0%;大肠杆菌对替米考星的耐药率高达94.0%,对阿莫西林耐药率为62.0%,对多西环素、多粘菌素E、庆大霉素、环丙沙星、恩诺沙星、头孢噻呋的耐药率在4.0%~24.0%之间。肠球菌对多西环素、庆大霉素、头孢噻呋三种药物的耐药率在29.6%~40.7%之间;对阿莫西林、恩诺沙星、环丙沙星三种药物的耐药率在7.4%~14.8%之间,对替米考星的耐药率为66.7%。葡萄球菌对替米考星的耐药率为39.1%,对阿莫西林、多西环素、庆大霉素、环丙沙星、恩诺沙星、头孢噻呋的耐药率均低于20.0%。上述试验结果表明:大肠杆菌和葡萄球菌在宠物菌群组成中占比较大;大肠杆菌和奇异变形杆菌的耐药情况较为严重。  相似文献   

零换水条件下3种异养硝化细菌对底部充氧池塘水质和尼罗罗非鱼生长、抗氧化能力的影响     

王淼  李忠徽  衣萌萌  卢迈新  王瑞宁  高风英  刘志刚 《水产学报》2020,44(7):1147-1155

为了研究3株异养硝化细菌对底部充氧尼罗罗非鱼养殖池塘水质的净化效果,选择初始体质量为(2.66±0.94) g的尼罗罗非鱼600尾,随机平均放入20个水泥池,实验设对照组1(普通曝气头)、对照组2(底部盘式微孔曝气器)、嗜吡啶红球菌(P1-2)实验组(底部盘式微孔曝气器)、粪产碱杆菌(P3-1)实验组(底部盘式微孔曝气器)、巨大芽孢杆菌(P5-2)实验组(底部盘式微孔曝气器),每组各4个重复,分别在养殖池塘定期泼洒终浓度为5×10~5 CFU/mL的异养硝化细菌菌液。测定了不同组中各项水质指标及鱼体生长、抗氧化能力指标的变化情况。结果显示,在实验过程中,所有组的总氮浓度均呈持续上升趋势,而加菌组的各指标积累量始终低于对照组,其中,P5-2对尼罗罗非鱼养殖水体的处理效果最为理想。P5-2组水体中的总氮累积量在整个养殖周期始终低于对照组1和对照组2。P3-1组水体中的总氮累积量在整个养殖周期始终低于对照组2。P1-2组水体中的总氮累积量在第8周和第10周显著低于对照组1和对照组2。P5-2、P3-1和P1-2组水体中的氨氮累积量在整个养殖周期始终低于对照组1和对照组2。P5-2组池塘水体中的亚硝酸盐氮累积量在第2周、第6周和第8周显著低于对照组2。养殖水体中泼洒异养硝化细菌可以提高尼罗罗非鱼的抗氧化功能。与对照组1相比,P3-1和P5-2组中尼罗罗非鱼血清中的超氧化物歧化酶(SOD)活性分别提高了12.10%和8.05%,与对照组2相比,P3-1和P5-2组中尼罗罗非鱼血清中的SOD活性分别提高了21.25%和16.87%。与对照组1相比,P1-2、P3-1和P5-2组中尼罗罗非鱼血清中的总抗氧化能力(T-AOC)分别提高了82.78%、98.68%和245.70%,与对照组2相比,P3-1和P5-2组中尼罗罗非鱼血清中的T-AOC分别提高了1.69%和76.95%。研究表明,在养殖池塘中添加异养硝化细菌,可有效维护养殖水质,提高尼罗罗非鱼的抗氧化能力,对鱼体生长无影响。  相似文献   

猪源肠球菌林克酰胺、截短侧耳素及链阳菌素A类耐药基因lsa(E)的检测及传播方式     

初胜波  王秀梅  张万江  刘琪  牟迪  刘思国 《中国预防兽医学报》2014,36(10)

为研究lsa(E)在猪源肠球菌中的流行情况及传播方式,本研究从广西某猪场分离的56株肠球菌中检测到15株携带多重耐药外排泵基因lsa(E)的肠球菌,利用脉冲场凝胶电泳(PFGE)对lsa(E)基因阳性的肠球菌进行亲缘关系分析,并对不同克隆型的菌株进行耐药表型和相关耐药基因型检测,通过Southem杂交定位lsa(E)基因在不同菌株中的位置.PFGE结果显示15株lsa(E)基因阳性的肠球菌共有7种不同的PFGE谱型,表明携带lsa(E)基因的肠球菌在同一猪场存在垂直传播的现象.药物敏感性试验结果显示,7株分离株除对红霉素、四环素、庆大霉素和环丙沙星100％耐药外,对利奈唑胺、氟苯尼考、利福平和左氧氟沙星也具有较高的耐药率,分别为57.1％、85.7％、71.4％和85.7％.耐药基因erm(B),aac(6')-Ⅰe-aph(2")-Ⅰa和aph(3")-Ⅲa的检出率分别为:100％、85.7％和72.4％;Southern杂交结果显示,lsa(E)基因在6株菌中定位于质粒22 kb～54 kb,而在1株菌中定位于染色体.本研究为临床制定合理措施控制lsa(E)快速传播提供依据.  相似文献   

乳酸菌对苜蓿草粉发酵品质的影响     

乔宏兴  史洪涛  王永芬  姜亚乐  边传周 《草业科学》2017,34(8)

通过为期60d的发酵,探讨添加乳酸菌对苜蓿(Medicago sativa)草粉发酵品质的影响。试验设4个处理,分别为添加无菌水(对照)、植物乳杆菌(Lactobacillus plantarum,LP)、屎肠球菌(Enterococcus faecium,EF)和植物乳杆菌+屎肠球菌(LP+EF)发酵苜蓿草粉,设5个时间点采样进行相关项目测定。结果表明,与对照组相比,发酵60d时各试验组发酵苜蓿草粉的评分提高,总酸含量显著升高(P0.05),pH显著降低;LP、LP+EF和对照组的干物质含量明显低于EF组;各试验组酸性洗涤纤维含量明显低于对照组;有氧暴露7d后,各试验组的pH均显著低于对照组、总酸含量均显著高于对照组(P0.05),且只有对照组中检测到酵母菌(Saccharomycetes)和霉菌(Mycete)。综上可知,添加乳酸菌对苜蓿草粉的发酵品质、稳定性及营养组成具有良好的改善作用。  相似文献   

The gut microbiome of Helicoverpa armigera enhances immune response to baculovirus infection via suppression of Duox-mediated reactive oxygen species     

Zhiqiang Tian  Xi Guo  JP Michaud  Meng Zha  Lin Zhu  Xiaoming Liu  Xiaoxia Liu 《Pest management science》2023,79(10):3611-3621

  相似文献   

肠球菌毒力因子的研究进展     

周霞  王东  王晓兰  刘雪梅 《中国兽医学报》2011,31(8)

肠球菌是人或动物肠道中的正常菌群。近年来在医学和兽医临床中肠球菌的感染已引起广泛关注。肠球菌除了具有特殊的耐药机制外,还拥有众多的毒力因子。本试验就目前已发现的肠球菌重要毒力因子作一综述。  相似文献