巨大芽胞杆菌YB-3的筛选、鉴定及其对生姜青枯病的生防效果研究

青枯病（bacterial wilt）是生姜上的一种细菌土传毁灭性病害,化学防治易污染环境且常规化学药剂很难在土壤中起到持续控病的作用,生物防治是其理想的防治方法。为开发对生姜青枯病有效的生防措施,对从生姜根际土壤中分离的一株生防细菌YB-3进行了鉴定,并对其生物学特性及生防效果进行了研究,以丰富生防菌株资源库。采用抑菌圈法筛选拮抗细菌,对效果最好的拮抗菌株做盆栽试验,测定其对生姜青枯病的防治效果,根据形态特征、生理生化特性以及16S rDNA序列对筛选得到的优良菌株进行鉴定。试验结果表明,该拮抗菌在平皿上对青枯菌的抑菌率为50.67%,盆栽试验对青枯病的防治效果为60.86%;经16S rDNA序列分析,并结合形态学和生理生化特征,将菌株YB-3鉴定为巨大芽胞杆菌Bacillus megaterium。YB-3是一株具有开发利用价值的姜青枯病生防菌株。     

Susceptibility pattern of bacterial isolates in equine ulcerative keratitis: Implications for empirical treatment at a university teaching hospital in Sydney

Corneal ulceration is a common ophthalmic condition in horses. It is frequently caused by trauma to the corneal surface, followed by secondary infection by commensal or pathogenic organisms including Streptococcus equi subspecies zooepidemicus, Pseudomonas aeruginosa and Staphylococcus spp. Emerging antimicrobial resistance amongst these organisms has raised the need for appropriate antimicrobial therapy selection, to optimise treatment efficacy while minimising further antimicrobial resistance. Medical records of 38 horses presented at the University Veterinary Teaching Hospital Camden for ulcerative keratitis between 2010 and 2020 were reviewed to identify those with positive bacterial cultures and antimicrobial susceptibility profiles (13/38). Common susceptibility patterns were identified and used to guide the empirical treatment of equine bacterial corneal ulcers. Pseudomonas spp. (64.3%), Streptococcus equi subspecies zooepidemicus (14.3%) and Actinobacillus spp. (14.3%) were most commonly identified. Susceptibility to amikacin, gentamicin and ciprofloxacin was observed in 100%, 66.7% and 85.7% Pseudomonas spp. isolates respectively. Resistance to polymyxin B and neomycin occurred in 85.7% and 71.4% of Pseudomonas spp., respectively. All Streptococcus equi subspecies zooepidemicus organisms in this study were susceptible to ceftiofur, cephalexin, penicillin and ampicillin, while they were all resistant to gentamicin, neomycin, enrofloxacin and marbofloxacin. Predominating in this study, Pseudomonas spp. maintained overall aminoglycoside susceptibility despite some emerging resistance, and good fluoroquinolone susceptibility. High resistance to Polymyxin B could have arisen from its common use as first-line therapy for bacterial corneal ulcers. Although further research is required, these new findings about predominant bacteria in equine corneal ulceration in the Camden region and their antimicrobial susceptibility patterns can be used to guide the empirical treatment of bacterial corneal ulcers in horses.     

高效产氢发酵细菌在不同气相条件下产氢

气相条件是影响高效产氢细菌产氢能力的重要生态因子之。间歇实验结果表明，空气中的氧分子是抑制高效产氢细菌－B49生长发酵的直接原因，二氧化碳也对B49的发酵产氢产生很大的抑制作用，而以氮气和氩气为气相能使B49发挥较高的产氢能力，氮气很可能对B49的发酵产氢有一定的促进作用。     

高效脱色菌的特性及其在染化废水厌氧处理中的生物强化作用

从活性污泥等微生物源中分离、筛选获得10株高效脱色菌，经鉴定其属于Pseudomonas,Bacillus，Xanthomonas，Erwinia，Alealigenes，Plesiomonas。对艳红染料生产废水脱色试验表明最适温度30℃，pH6.6～8.0，湿细胞浓度20～30!g*L-1;静置培养（兼氧）脱色率高于振荡培养；外加NADH、NADPH、易降解有机物和有机废水可强化脱色菌的脱色性能。为实现脱色菌的资源化应用，试验将PseudomonasD18,ErwiniaD17,AlcaligenesD19andPlesiomonasD124株脱色菌制成混合培养物和固定化细胞，分别投加于处理染化废水的厌氧反应器，结果发现在相同COD负荷、水力负荷条件下，投加固定化细胞的反应器，其脱色率可提高5!%～10!%，出水苯胺浓度提高40!%～65!%。电镜观察发现脱色菌在胶团内外持留、增殖。厌氧反应器性能的改善主要通过功能性微生物生物量和相关基因库量的增加而实现。     

ABR反应器性能研究：回顾与总结

厌氧折流板反应器ABR是一种新型高效厌氧反应器，本文主要是对ABR反应器问世以来关于它的研究及相关的工作进行了较为全面的整理与分析，找出待研究领域和问题，为今后的研究工作提供了基础和方向。     

光合细菌的特性及其在废水处理中的应用

本文系统综述了光合细菌的生理生化特征,并介绍了光合细菌法在废水处理中的应用和研究进展.     

Determination of Count and Uniformity Ratio of Shrimp by Machine Vision

Current shrimp quality evaluation is a subjective sum of visual, smell and texture characteristics, and the manual determination of count and uniformity ratio of a sample batch. The automation of this process is desirable for a more rapidly and objectively repeatable evaluation. As a first step towards this goal, the count and uniformity ratio of whole, headless, peeled-tail-on, and peeled-tail-off tiger and white shrimp were evaluated by a machine vision procedure. The experimental weight and view area were correlated by three different equations (linear, power, and forced-power curves) to find the best correlation. The pixel intesities as it relates to lightness-darkness values were also correlated to see if different forms and species could be distinguished by this method. Data, equations and statistics for the correlations are presented.     

富平关中奶山羊临床型乳房炎病原菌的分离鉴定

为进一步探讨关中奶山羊乳房炎感染病原菌的情况,对富平县三个不同乡镇的79头患病奶山羊,共118份奶样进行分离鉴定,共分离出7种共126个菌株.其中大肠杆菌36株,占28.5%;金黄色葡萄球菌28株,占22.2%;绿脓杆菌23株,占18.3%;链球菌21株,占16.7%;变形杆菌8株,占6.3%;蜡样芽孢杆菌6株,占4.8%;酵母菌4株,占3.2%.认为该研究区域的关中奶山羊乳房炎主要是由大肠杆菌,金黄色葡萄球菌、绿脓杆菌、链球菌所致.     

Comparison of physiological and yield traits between purple- and white-pericarp rice using SLs

Five physiological and eleven yield traits of two pairs of sister lines generated from a high generation with similar genetic background (SLs) for purple pericarp were investigated to explore the reasons behind low-yield production of colored rice. Of the five physiological traits examined, except grain anthocyanin content, there were generally similar trends between the P (purple-pericarp) lines and the corresponding W (white-pericarp) lines over two seasons (in the year 2009 and 2010 separately). The results demonstrated that the chlorophyll content of flag leaves, the net photosynthetic rate of flag leaves, and the grain anthocyanin content could be easily influenced by the environment. The physiological functions of the traits for the P lines were more active than those of the corresponding W lines in the year 2010. The grain anthocyanin content of the P lines was much greater in the year 2010 than in the year 2009 during the growth period. The investigation of yield traits revealed that the P lines had reduced 1000-grain weight, yield per plot and grain/brown rice thickness compared to the W lines. A difference comparison of these traits and a source-sink and transportation relationship analysis for these SLs suggested that small sink size was a key reason behind yield reduction of purple pericarp rice.