几种微生态制剂对生长猪生产性能和血清生化指标影响的比较研究

为了研究和比较几种不同微生态制剂对生长猪生产性能和血清生化指标的影响,试验选用60 kg左右的杜×长×大三元杂交生长猪150头,随机分为5组,每组设3个重复,每个重复10头,1组为对照组,饲喂基础日粮,2～5组分别在基础日粮中添加75 mg/kg赐美健、0.2%的枯草芽孢杆菌、0.2%金倍素和0.2%嗜酸乳杆菌,进行为期35 d的饲养试验。结果表明:与对照组相比,2～5组平均日增重分别提高0、2.78%、11.11%、9.72%,其中4(0.2%金倍素)组和5(0.2%嗜酸乳杆菌)组显著高于其他试验组(P<0.05);2～5组均有提高总蛋白、白蛋白含量,降低尿素氮含量和提高碱性磷酸酶活性的趋势,其中4(0.2%金倍素)组的总蛋白含量显著高于对照组(P<0.05)。说明在日粮中添加微生态制剂可以提高生长猪生长性能,改善血清生化指标,且以添加0.2%金倍素的效果最佳。     

不同土壤管理措施下南疆果园土壤微生物及酶活性特征

以新疆南部苹果（Malus domestica）园为对象,研究分析了不同管理方式对果园土壤微生物和酶活性变化的影响。结果表明,不同管理方式下南疆果园土壤中微生物总数量表现为,覆草＞生草＞免耕＞清耕。覆草区和生草区微生物总数量分别比免耕区增加32.90%和11.63%,比清耕增加38.09%和15.99%,果园土壤中细菌数量占绝对优势,其次是放线菌,真菌含量最少。微生物数量垂直分布规律特征明显,各处理细菌、放线菌、真菌数量均以0~20 cm土层最高,且随着土层深度的增加呈减少趋势。不同管理方式下土壤过氧化氢酶、蔗糖酶、脲酶3种酶活性特征表现为,覆草＞生草＞免耕＞清耕,且3种酶活性均随着土壤深度的增加呈下降趋势,与微生物数量分布规律一致。     

2株菌混合降解拟除虫菊酯类农药条件的优化及其协同作用

【目的】制备高效混合菌,为控制拟除虫菊酯类农药残留提供候选生物制剂。【方法】以蜡状芽孢杆菌(Bacillus cereus) ZH-3和金色链霉菌(Streptomyces aureus) HP-S-01混合菌为材料,采用单因素试验优化其生长和降解条件,高效液相色谱法(HPLC)测定其降解能力。【结果】 混合菌生长和降解拟除虫菊酯类农药的最优条件为接种量0.4 g/L、28 ℃、pH 7.5、振荡速率150 r/min,在此条件下培养72 h后,混合菌对50 mg/L氯氰菊酯的降解率达90%以上。混合菌高度耐受并降解氯氰菊酯,在氯氰菊酯初始质量浓度为100～500 mg/L时,降解率达到80%以上。混合菌最佳接种比例为1∶1,培养72 h后该比例混合菌对50 mg/L氯氰菊酯、氰戊菊酯和联苯菊酯的降解率分别为91.6%,92.5%和95.7%,比单一菌ZH3和HP-S-01的降解率均显著提高。【结论】 混合菌对3种拟除虫菊酯类农药的降解存在协同增效作用。     

高效丢糟纤维素分解复合菌系的构建与效果研究

[目的]筛选构建出对白酒丢糟分解能力强的复合菌系。[方法]从白酒丢糟堆腐物中分离筛选出产纤维素酶活性高的5株菌,混合后,在以丢糟为主要基质的培养基上固态发酵并多次传代培养,得到较稳定的纤维素分解复合菌系,测定其对丢糟的实际降解效果和产酶能力。[结果]该高效分解丢糟的复合菌系中包含4种菌株,稳定性较好。[结论]与单菌株相比,从白酒丢糟筛选并重新构建的复合菌系可大幅提高丢糟的分解能力及羧甲基纤维素酶酶活,并能在7 d内保持较好的稳定性。     

长春市朝阳区绿地土壤微生物变化研究

对长春市朝阳区不同功能绿地下不同植被类型土壤的基本理化状况及微生物含量变化进行了分析研究。结果表明:不同功能区土壤微生物含量随有机质、含水量变化表现为公园绿地广场绿地学校绿地居住区绿地;不同植被类型下土壤微生物含量变化表现为乔灌草灌草地;细菌变化较大,占有较大比例,而放线菌、真菌变化不明显。     

均匀设计优化提高羽毛粉消化率的研究

为提高羽毛粉的消化率,本试验以白鸡毛为原料,采用均匀设计试验优化羽毛粉加工工艺.研究结果显示,优化后的羽毛粉酶解工艺为:反应pH 7.5,反应温度46℃,碱性蛋白酶添加量0.9％,脂肪酶添加量0.3％,酶解时间3.5 h,在此工艺下处理得到的酶解羽毛粉呈淡黄色,颗粒细腻均匀且无腥味.羽毛粉中可溶性蛋白质含量为157.3...     

Methane release from millipedes and other soil invertebrates in Central Europe

The potential for methane production was investigated in 47 species of soil invertebrates. No detectable methane production was found in slugs, earthworms, potworms, oribatid mites, woodlices, springtails, centipedes, ants and soil diptera larvae. However, significant methane production was found in several temperate millipedes including some species from the order Julida (Leptoiulus trilobatus, Megaphyllum projectum, Megaphyllum unilineatum, Unciger transsilvanicus, Unciger foetidus, Leptoiulus proximus and Julus scandinavius). On the other hand, methane production was not confirmed in Cylindroiulus boleti which belongs to the same family. Members of the other orders (Glomerida and Polydesmida) did not release methane with the exception of one questionable recorded release in Polydesmus complanatus (Polydesmida, Polydesmidae). Methane producing species of millipedes showed significantly lower weight-specific rates of methane release than the cockroach Periplaneta americana and termite Prorhinotermes simplex. Methane release from millipedes was temperature-dependent; for the temperature range 5-25 °C, a Q₁₀ between 1.55 and 2.17 was calculated and the relationship between methane release and temperature was described by an exponential curve. Our results suggest that although overall methane fluxes from soil invertebrates under study cannot substantially influence a methane budget in most ecosystems, methane production is significant at least in some millipedes and therefore can impact mesoenvironments and microenvironments inhabited by these invertebrates. This work also confirms that methane production is not only supported by tropic soil invertebrates, but also by temperate species.     

Functional diversity of microbial communities in saline soils of the semidesert zone

The health status of microbial communities in soils of the Sulak Lowland (Dagestan) was estimated on the basis of data on their functional diversity. The health status of the microbial communities decreased in the following soil sequence: typical meadow soil > meadow-chestnut soil > dark chestnut soil > saline soil (solonchak). The low concentration of soluble salts (<1 meq/100 g of soil) had a positive effect on the functioning of the microbial communities. The health status of the microbial communities also depended on the soil humus content and pH conditions.     

Diversity and seasonal variations of mycorrhiza and rhizosphere bacteria in three common plant species at the Slovenian Ljubljana Marsh

Interactions between plants and microorganisms can significantly affect plant health and productivity as well as ecosystem functioning. Detailed knowledge of the tripartite relationships between plants, fungi, and bacteria, and their environment is still limited. In the present study, the soils adjacent to three plant species (Cruciata laevipes, Mentha piperita, Equisetum arvense) in the Ljubljana Marsh and the bulk, plant-free soil were analyzed for their bacterial community structure in June and October 2006. The terminal restriction fragment length polymorphism analysis indicated a different bacterial community structure in the rhizosphere and in bulk soil, however, with almost no seasonal changes between late spring and autumn samples and no apparent impact of the three plant species. In addition, root colonization of the three plant species by arbuscular mycorrhizal fungi (AMF) and dark septate endophytes (DSE) was microscopically assessed monthly from May until October 2006. A presumably accidental correlation between monthly precipitation and the degree of arbuscule formation, with the latter lagging 1 month, was noted for M. piperita, the most heavily colonized of the three plant species. With all three plants, the phosphorus content in roots correlated positively with most AMF structures. Microsclerotia of DSE were mainly abundant in autumn samples. Fungal diversity in roots was estimated using temporal temperature gradient gel electrophoresis separation of the fungal polymerase chain reaction products obtained for both 18S-rDNA and the 5.8S-ITS2-28S rDNA segments. No specific effects of either plant species or seasonal changes on mycorrhizal community structure were discernible.     

土壤酶活性对温度和CO2浓度升高的响应研究

作为土壤生态系统中的重要组成部分及生物元素循环的积极参与者,土壤酶在陆地生态系统地下生态过程中扮演着十分重要的角色。升高温度和(或)大气CO2浓度可能直接或者间接影响其活性。但目前对温度和(或)大气CO2浓度升高对土壤酶的影响机理、过程及土壤酶对其的响应机制研究相对薄弱。本文初步总结了国内外关于温度和(或)大气CO2浓度升高对土壤酶活性影响研究的现状,并指出了目前研究中存在的不足。