西藏林芝地区核桃病害鉴定报告

2006年我区重点林业县发生了较严重的核桃病害,严重影响了果农的增产增收,引起了各级政府的高度重视,自治区林业局责成我站时灾情进行调研,尽快查明病因,为防治提供指导。     

Surgical treatment of epibulbar melanocytomas by complete excision and homologous corneoscleral grafting in dogs: 11 cases

Objective The aim of the study was to evaluate the efficacy, outcome, and complications following penetrating sclerokeratoplasty and frozen homologous corneoscleral grafting for the management of extensive canine epibulbar melanocytomas. Methods Medical records of canine patients treated at three different veterinary hospitals between 1999 and 2010 were reviewed. Signalment, location and extent of melanocytomas, recurrence rate, and early and late complications were reported. Patients were re‐examined postoperatively to provide follow‐up information. Results Patients included one intact male, three castrated males, six intact females, and one spayed female, with a median age of 5 years (range, 3–9). German Shepherds were overrepresented. Tumors extended from 2 to 4 clock hours at the limbus and up to 17 mm from clear cornea to globe equator. One case showed iridocorneal angle invasion; corneal involvement was present in all cases, and lipid keratopathy was present in four cases. In two cases, there was incomplete resection owing to tumor extent. Follow‐up time ranged from 3 to 72 months (median, 17 months), with one case of intraocular tumor progression. Early complications included anterior uveitis (11/11), intracameral fibrin (5/11), hyphema (4/11), corneal edema (4/11), exuberant corneal granulation tissue (2/11), focal retinal edema (1/11), dyscoria (1/11), and partial suture dehiscence (1/11). Late complications included corneal fibrosis and/or pigmentation (11/11), faint anterior cortical cataracts (3/11), and lipid keratopathy (1/11). Vision was retained in all cases. Conclusions This technique offers a surgically challenging but effective treatment for extensive epibulbar melanocytomas. In this case series, complications were mild and transient, with preservation of ocular anatomy and function.     

Virulence factors of Escherichia coli serotypes associated with avian colisepticaemia

The current understanding of the pathogenesis of avian pathogenic Escherichia coli (APEC) in colisepticaemia is limited. This review discusses putative virulence determinants per se, such as a number of surface organelles including fimbriae and flagella; together with other factors such as iron sequestering mechanisms, which are involved in the survival of E. coli in the host rather than initiation of infection. It is concluded that avian colisepticaemia is a multi-factorial disease and that to date only a limited number of virulence factors of APEC have been thoroughly elucidated.     

Influence of cultivar and site of cultivation on levels of lipophilic and hydrophilic antioxidants in virgin olive oils (Olea Europea L.) and correlations with oxidative stability

Oxidation stability is an important property of olive oil quality and is affected by different antioxidant compounds whose levels may be influenced by cultivar, year and place of production. Polyphenols, tocopherols, carotenoids, chlorophylls and fatty acids levels were correlated to oxidative stability in olive oils from three experiments: cultivar influence (18 cultivars assessed for 4 years in the same place); environmental influence by mesoclimatic (4 cultivars from 17 sites in a single region for 4 years) and macroclimate conditions (3 cultivars from 3 different regions for 3 years). Total polyphenols and saturated on polyunsaturated fatty acids ratio were shown to be the major factors in oil antioxidant stability, according to multivariate regression models. Among the surveyed cultivars, oils from ‘Leccino’ and from three ‘local’, minor cultivars (‘Miniol’, ‘Regina’ and ‘Rossanello’) resulted in higher oxidative stability and oils from cultivars grown in Tuscany (central Italy) showed the highest oxidative stability by comparison with northern and southern regions.     

黄淮地区不同筋力冬小麦品种香气成分的GC MS分析

为了研究小麦麦香味的物质组成,以黄淮地区三种不同筋力的4个冬小麦品种（强筋品种西农9718、弱筋品种普冰143、中筋品种小偃22和西农88）为原料,利用固相微萃取气质联用技术定性定量分析了面粉和麸皮中的香气成分。结果表明,在西农9718、普冰143、小偃22和西农88小麦粉中分别检出58、57、56和58种香气成分,以烃类、醇类、酯类、羧酸类为主,其中又以C₁₅烯烃为主。在对应的麸皮中分别检出57、57、57和56种香气成分,以烃类、醇类、酯类、羧酸类、醛类、酮类、杂环类为主,其中又以C₆醇或酸为主。四个参试小麦品种的面粉和麦麸之间香气成分存在较大差异,而品种间的香气成分差异不大,说明香气成分与小麦筋力强弱无关。     

Fungicide strategies and resistance of Ramularia collo-cygni to demethylation and succinate dehydrogenase inhibitors in Austrian winter barley (Hordeum vulgare)

Journal of Plant Diseases and Protection - Ramularia collo-cygni B. Sutton and J.M. Waller is a major disease in Austrian barley-growing regions. To date, fungicide application is the most...     

Short-term temporal changes of bare soil CO2 fluxes after tillage described by first-order decay models

To further understand the impact of tillage on carbon dioxide (CO₂) emission, we compare the performance of two conceptual models that describe CO₂ emission after tillage as a function of the non-tilled emission plus a correction resulting from the tillage disturbance. The models assume that C in the readily decomposable organic matter follows a first-order reaction kinetics equation as     and that soil C-CO₂ emission is proportional to the C decay rate in soil, where C _soil( t ) is the available labile soil C (g m⁻²) at any time ( t ) and k is the decay constant (time⁻¹). Two possible relationships are derived between non-tilled ( F _NT) and tilled ( F _T) soil fluxes:     (model 1) and     (model 2), where t is time after tillage. The difference between these two models comes from an assumption related to the k factor of labile C in the tilled plot and its similarity to the k factor of labile C in the non-till plot. Statistical fit of experimental data to conceptual models showed good agreement between predicted and observed CO₂ fluxes based on the index of agreement (d-index) and with model efficiency as large as 0.97. Comparisons reveal that model 2, where all C pools are assigned the same k factor, produces a better statistical fit than model 1. The advantage of this modelling approach is that temporal variability of tillage-induced emissions can be described by a simple analytical function that includes the non-tilled emission plus an exponential term, which is dependent upon tillage and environmental conditions.