深州蜜桃黑斑病（Alternaria alternata）的研究Ⅱ．侵染规律和发病诱因

桃树健康和枯死组织普遍带有链格孢，枯死组织带菌率更高。病菌侵染果实主要在盛花期至盛花后约４０ｄ这段时期，侵染高峰在花萎期（４月下旬）。空中孢子捕捉试验证明，当气温稳定在２０℃以上时（５月中旬以后），雨后空中孢子迅速增长，此期空中孢子量与侵染高峰有密切关系。密植树、幼树发病较轻、树下部发病较轻，６月中旬以后套袋对黑斑病发病率无明显影响。     

凯氏定氮法测定灵芝破壁孢子粉中粗蛋白质含量的不确定度评定

对采用凯氏定氮法测定灵芝(Ganoderma lucidum)破壁孢子粉中粗蛋白含量的不确定度进行评定,结果表明合成相对标准不确定度为0.02%,扩展不确定度为0.04%。在本次孢子粉粗蛋白质测定中,引入不确定度的主要因素有盐酸标准溶液的浓度及样品测定中实际消耗的标准溶液体积。     

除草剂施用对农田丛枝菌根(AM)真菌影响的研究进展

为了探究除草剂施用对丛枝菌根(AM)真菌的影响,本文总结了近几年农田生态系统中除草剂对AM真菌的孢子萌发及活力、对宿主植物根系的侵染、群落结构、菌丝的琥珀酸脱氢酶(SDH)和碱性磷酸酶(ALP)活性等方面的研究进展,并对以后的研究进行了展望。以期为除草剂的合理使用、农业生产的可持续发展提供理论指导。     

Inactivation of Ichthyophonus spores using sodium hypochlorite and polyvinyl pyrrolidone iodine

Chlorine and iodine solutions were effective at inactivating Ichthyophonus spores in vitro. Inactivation in sea water increased directly with halogen concentration and exposure duration, with significant differences (P < 0.05) from controls occurring at all chlorine concentrations and exposure durations tested (1.5–13.3 ppm for 1–60 min) and at most iodine concentrations and exposure durations tested (1.2 ppm for 60 min and 5.9–10.7 ppm for 1–60 min). However, 10‐fold reductions in spore viability occurred only after exposure to halogen solutions at higher concentrations and/or longer durations (13 ppm total chlorine for 1–60 min, 5.9 ppm total iodine for 60 min, and 10.7 ppm total iodine for 1–60 min). Inactivation efficacy was greater when halogen solutions were prepared in fresh water, presumably because of combined effects of halogen‐induced inactivation and general spore instability in fresh water. The results have practical implications for disinfection and biocontainment in research laboratories and other facilities that handle live Ichthyophonus cultures and/or infected fish.     

Effectiveness of calcium hypochlorite,quaternary ammonium compounds,and sodium hypochlorite in eliminating vegetative cells and spores of Bacillus anthracis surrogate

BackgroundThe spore-forming bacterium Bacillus anthracis causes anthrax, an often-fatal infection in animals. Therefore, a rapid and reliable strategy to decontaminate areas, humans, and livestock from B. anthracis is very critical.ObjectivesThe aim of this study was performed to evaluate the efficacy of sodium hypochlorite, calcium hypochlorite, and quaternary ammonium compound (QAC) sanitizers, which are commonly used in the food industry, to inhibit spores and vegetative cells of B. anthracis surrogate.MethodsWe evaluated the efficacy of sodium hypochlorite, calcium hypochlorite, and a QAC in inhibiting vegetative cells and spores of a B. anthracis surrogate. We treated a 0.1-mL vegetative cell culture or spore solution with 10 mL sanitizer. The samples were serially diluted and cultured.ResultsWe found that 50 ppm sodium hypochlorite (pH 7), 1 ppm calcium hypochlorite, and 1 ppm QAC completely eliminated the cells in vegetative state. Exposure to 3,000 ppm sodium hypochlorite (pH 7) and 300 ppm calcium hypochlorite significantly eliminated the bacterial spores; however, 50,000 ppm QAC could not eliminate all spores.ConclusionsCalcium hypochlorite and QAC showed better performance than sodium hypochlorite in completely eliminating vegetative cells of B. anthracis surrogate. QAC was ineffective against spores of the B. anthracis surrogate. Among the three commercial disinfectants tested, calcium hypochlorite most effectively eliminated both B. anthracis vegetative cells and spores.     

甜菜多粘菌侵染及萌发特性研究

甜菜多粘菌在２５～３０℃条件下水培接种，５～１０ｄ在寄主根细胞内出现游动孢子囊，盆栽接种８ｄ后寄主根内出现原质体；１１～２５ｄ后出现粘质阿米巴体，４０ｄ左右出现休眠孢子囊堆。地上部分黄化症状与休眠孢子囊堆同时出现，焦枯型和坏死黄脉型症状分别迟于休眠孢子囊堆５０ｄ和１５ｄ     

基于SERS技术的基底增强效应对比及食源性芽孢快速检测

为了实现食源性芽孢的快速识别,该研究利用表面增强拉曼光谱技术,以产气荚膜梭菌芽孢（C.perfringens spores）、艰难梭菌芽孢（C.difficile spores）和生孢梭菌芽孢（C. sporogenes spores）为研究对象,将3种不同纳米溶胶材料AuNPs、AgNPs和Au@AgNPs作为表面增强拉曼散射（Surface-enhanced Raman scattering,SERS）基底对食源性芽孢的增强效应进行对比,确定较佳增强效果的纳米材料,进一步开展基于较优纳米溶胶材料为基底的SERS技术对不同种属食源性芽孢的光谱解析及快速识别研究。结果表明,Au@AgNPs对食源性芽孢的SERS增强效果最较好,其增强因子达3.49×104,且光谱特异性和重现性良好。经拉曼光谱解析,Ca2+-DPA的拉曼峰是三种食源性芽孢的共有标志特征峰,拉曼振动峰在1 017、1 440和1 570 cm-1波段显示且峰强度不同。C. perfringens芽孢在740、787、821、1 203、1 308和1 627 cm-1有独特的拉曼峰,C. sporogenes芽孢在852 cm-1有独特的拉曼峰,在1 017 cm-1（Ca2+-DPA）、1 081 cm-1（DNA、O-P-O）处峰位强度C. perfringens芽孢>C. sporogenes芽孢>C. difficile芽孢,在1 332 cm-1（核酸中腺嘌呤核酸）、1 440 cm-1（Ca2+-DPA）处峰位强度C. perfringens芽孢>C. difficile芽孢>C. sporogenes 芽孢,3种食源性芽孢的SERS图谱出峰位置和峰强度差异明显。结合主成分分析（Principal Component Analysis,PCA）和线性判别分析（Linear Discriminant Analysis,LDA）构建定性识别模型,经 PCA分析,其前三个主成分的累计贡献率达92.90%,然后利用LDA进行分析,其识别率可达到100%。结果表明,以Au@AgNPs为基底的SERS技术检测方法可以实现对食源性芽孢的快速识别,为食源性芽孢检测和食品安全检测提供了有效手段。     

寄生家蚕的内网虫属微孢子虫一新种

采用电子显微傍镜对ＳＣＭ７在家蚕体内发育的超微结构进行了详细的观察和研究表明，确认ＳＣＭ７微孢子虫属于微孢子虫门内网虫属一新种。     

家蚕微孢子虫（Nosemabombycis）孢子人工发芽的研究

研究表明，目前常用的适合于向昆虫培养细胞接种的Ｎｏｓｅｍａｂｏｍｂｙｃｉｓ孢子的几种人工发芽方法的发芽率存在较大差异．同一种方法在不同的发芽培养基中的发芽率也有所不同．并发现在Ｎ．ｂｏｍｂｙｃｉｓ孢子的人工发芽过程中Ｋ＋促进作用比Ｎａ＋明显，而且还证实Ｎ．ｂｏｍｂｙｃｉｓ孢子在人工发芽过程中的完全发芽时间为６０ｍｉ