周口地区番茄白粉菌的鉴定

[目的]鉴定周口地区番茄白粉菌的形态学及分子生物学.[方法]通过显微学对周口地区的番茄白粉病菌分生孢子及孢子梗的形态、大小进行观察对比,并分析了核糖体DNA转录间隔区（ITS）和进化树.[结果]在扫描电子显微镜下病菌分生孢子呈圆柱形或椭圆形,无支链;目的序列同来自日本番茄上的O.neolycopersici（AB094991）和来自美国番茄上的O.neolycopersici（AB163915）同源性最高聚为一支,与来自韩国绣球花上的O.hortensiae（JQ669944）等由于寄主植物不同而另聚为一条分支.[结论]不同物种的白粉菌间的遗传距离较远,来自周口地区的番茄白粉菌为O.neolycopersici.     

基于神经网络的硝基芳烃急性毒性QSAR研究

采用BP神经网络模型研究了45种硝基芳烃类化合物的结构与其急性毒性之间的关系,以硝基芳烃类化合物的量子化学参数作为输入,用3×4×1网络预测其急性毒性.采用内外双重验证的办法分析和检验所得模型的稳定性,所构建网络模型的相关系数为0.999 5,交叉检验相关系数为0.996 8,标准差为0.023 5,残差绝对值≤0.15,应用于外部预测集,外部预测集相关系数为0.998 4;而多元线性回归法(MLR)模型的相关系数为0.943 5,交叉检验相关系数为0.928 7,标准差为0.240 9,残差绝对值≤0.69,外部预测集相关系数为0.956 6.结果表明,BP神经网络模型获得了比MLR模型更好的拟合效果.     

Impacts of changing spatial scales on CPUE–factor relationships of Ommastrephes bartramii in the northwest Pacific

The selection of spatial scales is of particular importance in modeling relationships between fishery abundance and its influencing factors, because these relationships are significantly affected by spatial scale. Here, we explore the spatial scale effects of catch per unit effort (CPUE)–factor relationships for Ommastrephes bartramii in the northwest Pacific. The original commercial fishery data and oceanographic factors were tessellated to 12 spatial scales from 5′ to 60′ with an interval of 5′. Under the original scale and 12 tessellated scales, we constructed the generalized additive models (GAMs) to model the relationships between the O. bartramii CPUE and the influencing factors, including Year, Month, Latitude (Lat), Longitude (Lon), sea surface salinity (SSS), sea surface temperature (SST), sea surface chlorophyll‐a (Chl‐a) concentration, and sea surface height (SSH). Our multi‐scale analysis showed that the relationships are sensitive to spatial scales. Among the factors, Year, Month, and SSS share quadratic polynomial scaling relations; Lat, SST, and Chl‐a illustrate power law scaling relations; Lon has a linear scaling relation; and SSH presents an exponential scaling relation. Considering the scale sensitivity of the factor sort‐order and the accumulation of explained residual deviance in GAM, we suggest 30′–45′ as the optimal range of spatial scales for analyzing the CPUE–factor relationships for O. bartramii. Our research improves understanding of the impacts of changing scales in fisheries and provides a potential method for the selection of a suitable spatial scale for fisheries analysis and resource surveying.     

Length–weight relationships for 21 coastal fish species of the Azores, north-eastern Atlantic

Length–weight relationships were estimated for 21 coastal fish species of the Azores, namely Abudefduf luridus, Bothus podas, Chromis limbata, Coris julis, Diplodus sargus, Echiichthys vipera, Gaidropsarus guttatus, Labrus bergylta, Mullus surmuletus, Phycis phycis, Pomatomus saltator, Sarda sarda, Scorpaena maderensis, Scorpaena notata, Seriola rivoliana, Serranus atricauda, Sparisoma cretense, Sphyraena viridensis, Synodus saurus, Thalassoma pavo and Trachinotus ovatus. Significant length–weight relationships were found for all species. Sexual dimorphism did not affect the length–weight relationships, except in the cases of S. cretense and C. julis. Length–length equations for converting size measurements (standard length (SL) and fork length (FL) to total length (TL)) are also presented for all fish species.     

Water use and conservation for inland aquaculture ponds

The general hydrological equation, inflow = outflow ± change in storage, can be used to make accurate estimates of water use by ponds for inland aquaculture projects. The primary inflows are precipitation, runoff and regulated water additions. The main outflows are evaporation, seepage, overflow after storms and intentional discharge. Water conservation measures such as maintaining storage capacity in ponds equal to the normal, maximum daily precipitation, reduction in seepage beneath dams and through pond bottoms, fish harvest without draining ponds, and water re-use are discussed. Even with the implementation of water conservation measures, pond aquaculture is a water- intensive endeavour which consumes more water per unit of area than irrigated agriculture. However, the value of aquacultural production per unit of water used greatly exceeds that of irrigated agriculture. Reduction in effluent volume is the most effective water saving means, and not only reduces water consumption but also reduces the pollution potential of pond aquaculture.     

Value-added sampling for fishery independent surveys: Don’t stop after you’re done counting and measuring

Most fishery independent surveys count, weigh, and measure the majority of species caught. Many surveys also collect selected body structures for in-lab age determinations for selected species. We provide examples from the Northeast Fisheries Science Center's (NEFSC) bottom trawl survey that detail the development of at-sea sampling to elucidate age, growth, maturity, fecundity, spawning season, stomach contents, diet composition, condition, habitat types and prey preferences, basic oceanography (or limnology), and bioenergetics for a suite of diverse species. We show how the development of new methodologies and technologies has decreased both deck-time and time in the lab for processing many of the samples required to provide information on the topics listed above. As new technologies develop to make our trawl catch processing more efficient, we assert that we can notably increase the amount of information collected from trawl surveys with little additional effort. We show that with marginally additional catch processing time on the deck, at-sea sampling can provide a significant return on the knowledge of aquatic and marine resource species, non-resource species, habitats, food webs, and the ecosystems within which they occur. As observing systems continue to expand their remit to provide ecosystem management advice, the need for increased efficiencies on fisheries surveys will remain.     

5种螺蛳属动物和中国圆田螺COI基因序列分析

以腹足纲,田螺科,螺蛳属（Ｍａｒｇａｒｙａ）的５种动物和中国圆田螺（对照）为研究对象,提取肝脏组织ＤＮＡ,ＰＣＲ扩增线粒体细胞色素Ｃ氧化酶Ｉ（ＣＯＩ）基因,纯化后测序,并用ＤＮＡＳｔａｒ软件包对序列进行编辑,ＭＥＧＡ软件绘制基因Ｎ－Ｊ树和ＵＰＧＭＡ系统树。结果表明：ＣＯＩ基因大小为６３６ｂｐ,系统树显示,螺蛳、滇池螺蛳、牟氏螺蛳、 乳顶螺蛳共同组成一个大支,阳宗海螺蛳与上述动物的亲缘关系较远,成为螺蛳属中单独进化的类群;中国圆田螺与螺蛳属动物的遗传距离达０．４０４％ ～０．５１８％,亲缘关系很远。     

Mobilising environmental information about lesser-known plants: the value of two neglected levels of description

Difficulties exist at present in predicting the performance of many lesser-known plants because of the high cost of elucidating their environmental relationships using conventional experimental methods. It is pointed out that prior to the emergence of modern plant science, mankind must have been using coarser methods very similar to those observable in human communities today. Because these instinctive human methods appear to be very effective, a fresh look at them could lead to alternative ways of defining the environmental relationships of lesser-known plants. These methods could be much cheaper and quicker than conventional methods and could make use of a large pool of knowledge about plants which is held in human communities. The most appropriate medium for interaction with the public in this way appears to be shareware software, and a package called PLANTGRO which could aid such developments is foreshadowed.     

赖草属植物的表型分支系统学分析

基于21个形态性状,对34个赖草属类群进行了表型分支分析.经简约分析,得到了70颗同等最大简约分支树,其严格一致树显示:①赖草属在形态上为高水平的分化,在组间及种间均存在着广泛的变异,不支持现有的赖草属分组;②北美的赖草属植物与欧亚大陆赖草属植物亲缘关系较远;③L.duthiei、L.duthiei var.longearistatus和L.coreanus与其他赖草植物的亲缘关系较近,支持将其从猬草组合到赖草属中.鉴于性状状态间存在着较多的平行和逆转进化,同时性状状态间的演化可能平行的、多次的或者是特化的,这样复杂的演化关系很难通过简约化的分支分析来重建,结合细胞学和DNA序列分析很可能是必需的.     

HPPD抑制剂的研究进展

对新型除草剂对羟苯基丙酮酸双氧化酶 (HPPD)抑制剂的发现过程、作用机制、结构特征、构效关系以及合成方法作了较为详细的综述