河南小麦白粉病逐年春季流行时间动态

1980－1997年对河南小麦白粉病春季流行的时间动态进行了系统分析。结果表明：（1）逐年春季流行程度波动较大,中度以上流行年份有9年,但流行程度之间没有明显的周期性。（2）逐年春季流行的时间动态有明显差异,特大流行年份白粉病发病特早,指数增长期和逻辑斯蒂期比其它年份长30d以上,表观侵染速率达0.16以上;大流行年和中度流行年份的始发期相同,表观侵染速率前者达0.16,后者只有0.12-0.14;轻度流行年始发期晚,指数增长期和逻辑斯蒂期短,表观侵染速率低,导致最终病情指数低。（3）小麦越冬返青期的降水量、雨日、水份积分指数、相对湿度对白粉病的始发期有显著影响,但白粉病的最终流行程度主要取决于小麦拔节孕穗期的水份积分指数、温雨系数、降水量、雨日和温度。     

Effect of common bunt on the frost resistance and winter hardiness of wheat (Triticum aestivum L.) lines containing Bt genes

In order to determine the effects of bunt inoculation on frost resistance and winter hardiness in lines containing resistance genes, the bunt [Tilletia foetida (Wallroth) Liro, T. caries (DC.) Tulasne] susceptibility of wheat lines containing bunt resistance genesBt1 to Bt10 and the effect of the year on the degree of infection were studied over six years from 1991 to 1997 in an artificial inoculation nursery. Uninoculated and artificially inoculated wheat plants were tested for frost resistance in the phytotron in 1995 and in the field in boxes in three years from 1994/95 to 1996/97. The line withBt10 was very resistant, lines with Bt5, Bt6, Bt8 and Bt9 were resistant, the line with Bt4 was moderately resistant, those with Bt2 and Bt3 were moderately susceptible, the line with Bt1 was susceptible and the line with Bt7 was very susceptible to the local bunt population in Hungary. Bunt incidence also varied over years. The frost resistance of the Bt lines was generally lower after bunt inoculation than that of uninoculated plants. The increased frost kill in inoculated plants was not correlated with the extent of varietal susceptibility to bunt. Some lines with resistance, namely those with Bt5 (1.6% infection), Bt8 (0.6%) and Bt10 (0.0%), suffered significantly greater frost kill in the young plant stage as the result of bunt inoculation. By contrast, the Bt7line had excellent frost resistance and winter hardiness but suffered the greatest extent of bunt infection, whereas the Bt6 line had good frost resistance and good bunt resistance. This revised version was published online in July 2006 with corrections to the Cover Date.     

粘膜病病毒感染幼鹿的病原流行病学调查

应用双抗体夹心酶联免疫吸附试验（ＥＬＩＳＡ）对４个地区幼鹿感染粘膜病病毒（ＭＤＶ）进行了检测,感染率为６０．０％￣８６．７％,表明上述地区幼鹿存在着广泛的ＭＤＶ感染。为今后粘膜病的防治提供了流行病学资料与理论依据。     

中华绒螯蟹“腹水病”及“抖抖病”并发病病原的研究

于1998～1999年对中华绒螯蟹主要细菌性疾病“腹水病”、“抖抖病”并发病病原进行研究。结果表明经细菌学鉴定6株病原菌,其中5株为嗜水气单胞菌(Aeromonas hydrophila),1株为拟态弧菌(Vibrio mimicus),用细菌人工感染蟹,其LD     

泄殖腔感染鸡传染性支气管炎病毒的临床试验

本试验选用鸡传染支气管炎强度Ｍ４１株,通过泄殖腔和滴鼻两种途径对７日龄ＳＰＦ鸡进行了临床感染试验。经临床观察、病理解剖和病毒分离证明泄殖腔是传染性支气管炎病毒（ＩＢＶ）感染鸡的一种途径。尽管两种感染途径引起试验鸡的发病率相同,但在组织器管的致病性和病毒分离方面存在明显差异。经泄殖腔感染鸡的肾病变发生率和肾脏中ＩＢＶ的分离率均匀为１７．９％,而经滴鼻感染鸡的肾病变发生率和肾脏中ＩＢＶ中的分离率均为６     

Quantitative Trait Loci for Resistance to Stripe Disease in Rice （Oryza sativa）

In order to map the quantitative trait loci for rice stripe resistance, a molecular linkage map was constructed based on the F2 population derived from a cross between Zhaiyeqing 8 and Wuyujing 3. Reactions of the two parents, F1 individual and 129 F2:3 lines to rice stripe were investigated by both artificial inoculation at laboratory and natural infection in the field, and the ratios of disease rating index were scored. The distribution of the ratios of disease rating index in Zhaiyeqing 8/Wuyujing 3 F2:3 population ranged from 0 to 134.08 and from 6.25 to 133.6 under artificial inoculation at laboratory and natural infection in the field, respectively, and showed a marked bias towards resistant parent (Zhaiyeqing 8), indicating that the resistance to rice stripe was controlled by quantitative trait loci (QTL). QTL analysis showed that the QTLs detected by the two inoculation methods were completely different. Only one QTL, qSTV7, was detected under artificial inoculation, at which the Zhaiyeqing 8 allele increased the resistance to rice stripe, while two QTLs, qSTV5 and qSTV1, were detected under natural infection, in which resistant alleles came from Zhaiyeqing 8 and Wuyujing 3, respectively. These results showed that resistant parent Zhaiyeqing 8 carried the alleles associated with the resistance to rice stripe virus and the small brown planthopper, and susceptible parent Wuyujing 3 also carried the resistant allele to rice stripe virus. In comparison with the results previously reported, QTLs detected in the study were new resistant genes to rice stripe disease. This will provide a new resistant resource for avoiding genetic vulnerability for single utilization of the resistant gene Stvb-i.     

牙鲆仔鱼肠道白浊病病原菌的分离鉴定

对工厂化育苗中患肠道白浊病的牙鲆仔鱼进行了病原菌的分离与特性鉴定,从众多患病仔鱼的肠 道中均分离到几乎纯一的细菌,并对仔鱼的分离培养物进行形态特征检查及理化特性鉴定,结果初步表明所 分离鉴定的病原菌为鳗弧菌(Vibrio anguillarum),为牙鲆仔鱼肠道白浊病的致病菌,测定了对常用抗菌类药 物的敏感性,结果表明分离菌株对环丙沙星等11种药物高度敏感,对林可霉素等4种药物中度敏感,对利福 平等3种药物耐药。     

宁夏两家猪场猪萨佩罗病毒的检测与多样性分析

为了解宁夏地区猪群中萨佩罗病毒(PSV)的感染流行情况,本研究通过RT-PCR的方法对不同区域的2个规模化养猪场的160份临床健康猪咽拭子和肛拭子样品进行了检测。试验表明,所检的2个养殖场均存在PSV感染,总体平均阳性率为61.25%,其中咽拭子检出率为7.5%,肛拭子猪检出率为58.75%。试验结果表明PSV在宁夏地区普遍存在。     

What drives changes in the virulence and antibiotic resistance of Vibrio harveyi in the South China Sea?

To understand the driving environmental factors in changes of bacterial virulence and antibiotic resistance, we determined the prevalence, antibiotic resistance and antibiotic resistance and virulence genes of Vibrio harveyi isolated from diseased marine fish in south coastal China. We isolated 2, 52 and 53 V. harveyi strains from Fujian, Hainan and Guangdong, respectively, and identified them by multilocus sequence analysis of 16S rRNA-toxR_Vh-rctB. Nine typical virulence genes were represented at a higher average in Hainan (7.39 ± 0.24) than in Guangdong (6.91 ± 0.28). Five atypical virulence genes were detected in some isolates. In particular, flaC and vvh were detected in more than 60% of isolates. Their average number was significantly higher in Hainan (2.30 ± 0.20) than in Guangdong (1.70 ± 0.10). Multidrug resistance was widespread with an average resistance to 4.57 ± 0.18 of 15 antibiotics. Both the average number of antibiotic resistance and antibiotic resistance genes were higher in Hainan (5.25 ± 0.27 and 1.11 ± 0.15, respectively) than in Guangdong (3.87 ± 0.21 and 0.75 ± 0.10, respectively). This study demonstrated that there were more virulence genes and greater drug resistance in Hainan than in Guangdong, suggesting that warmer temperature and antibiotics pollutants probably enhance antibiotic resistance and bacterial infection.     

Outbreak of equine coronavirus infection among riding horses in Tokyo,Japan

In 2020, an outbreak of equine coronavirus (ECoV) infection occurred among 41 horses at a riding stable in Tokyo, Japan. This stable had 16 Thoroughbreds and 25 horses of other breeds, including Andalusians, ponies and miniature horses. Fifteen horses (37 %) showed mild clinical signs such as fever, lethargy, anorexia and diarrhoea, and they recovered within 3 days of onset. A virus neutralization test showed that all 41 horses were infected with ECoV, signifying that 26 horses (63 %) were subclinical. The results suggest that subclinical horses played an important role as spreaders. A genome sequence analysis revealed that the lengths from genes p4.7 to p12.7 or NS2 in ECoV differed from those of ECoVs detected previously, suggesting that this outbreak was caused by a virus different from those that caused previous outbreaks among draughthorses in Japan. Among 30 horses that tested positive by real-time RT-PCR, ECoV shedding periods of non-Thoroughbreds were significantly longer than those of Thoroughbreds. The difference in shedding periods may indicate that some breeds excrete ECoV longer than other breeds and can contribute to the spread of ECoV.