将野生二粒小麦的大粒和籽粒高蛋白质含量性状向普通小麦转移

将引自以色列的4份野生二粒小麦与普通小麦杂交、回交。从F5、BC1F4、BC2F3代中选出的128个外部形态性状已基本稳定的株系中，选出千粒重高于对应普遍小麦亲本（扬麦5号和扬麦158）5g以上的株系17个，籽粒蛋白质含量比普通小麦亲本高4％以上的株系12个，其中有5个株系的千粒重和籽粒蛋白质含量均显著高于普通小麦。表明野生二粒小麦可用于提高普通小麦栽培品种千粒重和籽粒蛋白质含量，且可以实现两者的同步改良。     

嗜水气单胞菌胞外蛋白酶对鲫鱼的致病性

以提纯的嗜水气单胞菌胞外蛋白酶注射异育银鲫,鲫鱼出现典型的嗜水气单胞菌引起的败血症症状;病鱼体表充血、出血,鳃苍白,腹部膨大,肛门红肿突出,腹腔内有红色的腹水,肠壁充血发炎;背部肌肉注射部位发生液化、糜烂,鳞片竖起。病鱼各组织器官都有病变,其中尤以肝、肾最为严重：肝脏肿大,质地脆弱,肝细胞水肿,胞浆结构疏松;肾小体坏死以至解体,肾小管上皮细胞也发生病变。体外试验表明,正常鲫鱼血精中有某种成分能够抑     

朱鹮人工饲养群体扩增DNA指纹分析

利用 2 0个 10碱基的随机引物对陕西朱保护站人工饲养的 10只朱 (N ipponia nippon)进行了DNA扩增。结果表明 ,其中 16个引物对所测个体产生了一致的扩增 DNA带纹 ,4个引物产生的 DNA带纹具有多态性。据此计算了扩增 DNA指纹条带的平均带纹相似率为 0 .85 ,平均杂合度为 0 .5 4;在此基础上 ,分析了 10只朱的亲缘关系关系并绘制了相关关系聚类图     

胶东半岛地区番茄褪绿病毒的快速检测与鉴定

番茄褪绿病毒(Tomato chlorosis virus,To CV)是最近传入我国的重要植物病毒,可通过媒介昆虫烟粉虱传播。为了探索利用媒介昆虫快速、高效检测该病毒的方法,本研究对胶东半岛重要蔬菜产区青岛和烟台两地烟粉虱体内To CV进行检测与鉴定。结果表明:该地区烟粉虱种群体内均可检测到To CV,说明利用媒介昆虫烟粉虱可以快速检测该入侵病毒。     

国家级自然保护区——安徽升金湖的保护价值刍议

安徽升金湖国家级自然保护区的湿地类型多样,生物资源丰富,在全国具有一定的典型性和代表性。保护区为保护升金湖完整的湿地生态系统、物种生存和进化提供了有利场所,特别是为白鹤、白头鹤、东方白鹳等珍稀濒危鸟类提供了一块重要的越冬地和停歇地,保护区不仅是长江中下游区域的生态安全屏障和重要水源地,也是保护和研究我国一些特有珍稀物种的重要生境,是我国华东地区,尤其是长江中下游区域少有的生物基因库和生物多样性保护基地,具有重要的保护价值。     

病毒抑制剂对蝴蝶兰病毒植株的脱毒效果

选取感染建兰花叶病毒(CyMV)和齿兰环斑病毒(ORSV)的蝴蝶兰植株进行离体培养,在芽增殖培养基中添加不同的病毒抑制剂,研究对CyMV和ORSV病毒的脱除效果.结果表明,氨基寡糖素具有很好的脱毒效果,对CyMV的脱除率为83.33％,对ORSV的脱除率为66.67％;病毒唑次之,对CyMV的脱除率为83.33％,对ORSV的脱除率为50％;中药类的脱毒效果不明显.     

筛选根际促生细菌防治蔬菜根结线虫病

 自武汉市蔬菜基地30种蔬菜作物的根际土壤中共分离了细菌分离物1334株.室内检测其对目标根结线虫(Meloidogyne incognita)2龄幼虫的致死作用,获得32株致死率80%以上的有效菌株,占总细菌分离物的2.4%.盆栽促生试验表明:此32株有效菌株中有9株对番茄的生长表现出了明显的促进作用.以菌悬液(10⁹CFU/mL)浸根对此9株菌株进行进一步促生防虫试验,得到4株兼具促生防虫效果的根际细菌分离物,其防效均在 60%以上.     

Effects of short‐term starvation on the rhythmic expression of microRNAs in skeletal muscle of goldfish (Carassius auratus)

Molecular oscillators exist in peripheral tissues such as in skeletal muscles and diet is a dominant factor to affect Zeitgeber for peripheral clocks. MicroRNAs (miRNAs) play an important role in muscle cell proliferation and differentiation. However, the knowledge of starvation effects on miRNA rhythmic expression remains limited in teleost. In this study, the circadian expression pattern of miRNAs was investigated in goldfish muscle upon restricting feeding treatment. The data showed that 15 miRNAs exhibited a daily rhythmicity among the 70 miRNAs assayed in muscles of normally fed goldfish. While after 7‐day and 15‐day fasting treatment, 23 and 18 miRNAs showed circadian rhythmicity in goldfish muscles respectively. Only 4 miRNAs (miR‐23a, miR‐29, miR‐199a‐3p and miR‐455) exhibited a daily rhythmicity in all three groups of different nutrient treatments. Correlation analysis of the circadian‐miRNAs indicates different feeding stimulation could alter the circadian‐miRNA components and their expression profile in skeletal muscle upon short‐term feed deprivation. These miRNAs may play important roles in regulating circadian expression of genes involved in muscle cell differentiation and growth by nutritional alteration, thus having a potential application in fish aquaculture.     

Effects of body weight, water temperature and ration size on ammonia excretion by the areolated grouper (Epinephelus areolatus) and mangrove snapper (Lutjanus argentimaculatus)

The effects of body weight, water temperature and ration size on ammonia excretion rates of the areolated grouper Epinephelus areolatus and the mangrove snapper Lutjanus argentimaculatus were investigated. Under given experimental conditions, L. argentimaculatus had a higher weight-specific ammonia excretion rate than E. areolatus. Weight-specific ammonia excretion rates of fasted individuals of both species showed an inverse relationship with body weight (W, g wet wt.), but a positive relationship with water temperature (t, °C). The relationships for total ammonia nitrogen (TAN) were: E. areolatus: TAN (mg N kg⁻¹ d⁻¹)=21.4·exp^0.11t·W^−0.43 (r²=0.919, n=60); L. argentimaculatus: TAN (mg N kg⁻¹ d⁻¹)=121.5·exp^0.12t·W^−0.55 (r²=0.931, n=60). Following feeding, the weight-specific ammonia excretion rate of E. areolatus increased, peaked at 2 to 12 h (depending on temperature), and returned to pre-feeding levels within 24 h. A similar pattern was observed for L. argentimaculatus, with a peak of TAN excretion being found 6 to 12 h after feeding. Stepwise multiple regression analysis indicated that weight-specific TAN excretion rates of both species increased with increasing temperature and ration (R, percent body wt. d⁻¹): E. areolatus: TAN (mg N kg⁻¹ d⁻¹)=22.8·t−28.8·R−378.2 (r²=0.832, n=24); L. argentimaculatus: TAN (mg N kg⁻¹ d⁻¹)=22.9·t−25.4·R−216.4 (r²=0.611, n=24). The effect of body weight on weight-specific postprandial TAN excretion was not significant in either species (p>0.05). This study provides empirical data for estimating ammonia excretion of these two species under varying conditions. This has application for culture management.     

Nocardia seriolae infection in the three striped tigerfish, Terapon jarbua (Forsskål)

An epizootic in pond cultured three striped tigerfish, Terapon jarbua , in Taiwan was caused by Nocardia seriolae . Diseased fish first showed clinical signs and mortalities in February and March 2003. The cumulative mortality within 2 months was 2.4% (1200 of 50 000) and affected fish were 7 months old with total lengths from 18 to 25 cm. Most affected fish were pale and lethargic with haemorrhages and ulcers on the skin. The most significant gross pathological changes were varying degrees of ascites and enlargement of the spleen, kidney and liver. Obvious white nodules, varying in size, were found in these organs. Bacteria were either coccal or filamentous in appearance, with bead-like forms. Isolates from diseased fish were characterized using the API ZYM (Analytical profile index; Bio Mérieux, France) systems and conventional tests and identified as Nocardia sp. The isolate was designated NS127 and was confirmed as N. seriolae by a polymerase chain reaction assay that gave the expected specific 432 bp amplicon. In addition, its 16S rDNA sequence gave 100% sequence identity with N. seriolae . A partial sequence of the 16S rRNA gene, heat shock protein gene and RNA polymerase gene (rpo B) of NS127 and the type strain of N. seriolae BCRC 13745 formed a monophyletic clade with a high sequence similarity and bootstrap value of 99.9%. White nodules induced in experimental fish were similar to naturally infected cases and N. seriolae was re-isolated on brain heart infusion agar. This is the first report of N. seriolae -infection in three striped tigerfish in aquaculture.