我国广西数种圆蛛记述(蜘蛛目:圆蛛科)

本文记述了广西圆蛛科的5种蜘蛛,其中包括2新种:1.简腹圆蛛,新种 Araneustubabdominus sp.nov.;2.淡绿肥蛛 Larinia phthisica(L Koch,1871);3.椭圆新圆蛛 Neosconaelliptica Tikader et Bal,1981国内新纪录种;4.广西齐吉蛛,新种 Zygiella guangxiensis sp.nov.;5.纳氏齐吉蛛 Zygiella nadleri Heimer,1984,国内新纪录种,指出 Zygiella melanocraniaYin et al.,1990为本种的误定。模式标本保存在河北教育学院,副模保存在广西农业大学。     

广西蜘蛛名录（Ⅰ）跳蛛科（Salticidae）

本文记述了广西跳蛛科蜘蛛３０属６７种，并列出其分布和主要生境，其中新种１种．中国新记录种８种。     

茶叶挥发物对鞍形花蟹蛛觅食行为的影响

为了探明茶叶挥发物在鞍形花蟹蛛(Xysticus ephippiatus Simon)搜寻猎物——茶尺蠖(Ectropis obliqua Prout)过程中的作用,采用固相微萃取气相色谱质谱联用技术研究了茶尺蠖取食对茶树叶片挥发物释放的影响,并通过蜘蛛行为观测平台研究了蟹蛛在不同味源侧(觅食斑块)的活动行为。结果表明:对照叶片没有释放出挥发物,经茶尺蠖幼虫取食后的叶片能释放31种挥发物,其中有12种绿叶挥发物、9种萜类及其衍生物、4种芳香族挥发物和6种未知化合物。行为观测表明,雌、雄蟹蛛进入处理味源侧(茶尺蠖取食后的茶树叶片)和对照味源侧(未损伤茶树叶片)的初次选择均不存在差别(P>0.05),雌蛛进入处理味源侧和对照味源侧的频次分别为3.37±0.18和3.43±0.15,二者无明显区别(P>0.05);雄蛛进入两侧的频次分别为3.86±0.21和3.66±0.20,也无明显区别(P>0.05);雌蛛在处理味源侧和对照味源侧的停留时间分别为(922.57±19.59)s和(818.89±29.63)s,有极显著差异(P<0.01),雄蛛在两侧的停留时间分别为(937.97±18.05)s和(814.83±18.97)s,也有极显著差异(P<0.01),表明雌蛛、雄蛛在处理侧的停留时间明显延长。这说明,猎物取食诱导改变了茶树叶片挥发物的释放,而鞍形花蟹蛛能感知挥发物的变化并由此调整在不同觅食斑块中的停留时间。另外,本文还讨论了挥发物在蟹蛛搜寻猎物过程中的生态学意义。     

星豹蛛对小菜蛾捕食作用的电泳检测研究

本研究应用聚丙烯酰胺凝胶电泳技术,对星豹蛛雌雄蛛(Pardosa astrigera)捕食猎物小菜蛾(Plutella ma-culipennis Curtis)前后酯酶同工酶的变化进行了电泳分析。结果表明,在星豹蛛体内可以检测到被捕食猎物的特有酯酶同工酶酶带,且雌蛛最佳检测时间为捕食后3～6h,雄蛛为6～9h,猎物在星豹蛛雌蛛体内的消化时间短于雄     

应用微核试验和单细胞凝胶电泳技术检测农药对蜘蛛的遗传毒性

应用蜘蛛血细胞微核试验和单细胞凝胶电泳试验研究了两种杀虫剂——吡虫啉和阿维菌素对蜘蛛头胸部和腹部的遗传毒性。结果表明:各供试浓度吡虫啉和阿维菌素对蜘蛛血细胞微核率均有明显影响,与对照组相比有显著性差异(P<0.05,P<0.01);且随着两种农药浓度升高,血细胞微核率显著增加,存在明显的剂量效应关系(吡虫啉浓度与星豹蛛头胸部血细胞微核率相关系数r=0.672 8,腹部为r=0.800 6;阿维菌素与星豹蛛头胸部血细胞微核率相关系数r=0.989 9,腹部为r=0.985 8)。吡虫啉和阿维菌素对星豹蛛血细胞DNA损伤有明显的剂量效应关系(吡虫啉浓度与星豹蛛头胸部血细胞DNA损伤相关系数r=0.948 2,腹部为r=0.970 4;阿维菌素与星豹蛛头胸部血细胞DNA损伤相关系数r=0.978 1,腹部为r=0.975 6)。两种农药在同一浓度下,对星豹蛛腹部血细胞微核率和DNA损伤程度明显大于头胸部。     

淮北棉田害虫与捕食性天敌群落动态变化研究

对淮北棉田害虫和捕食性天敌群落动态变化进行了研究。田间系统调查共发现害虫35种,捕食性天敌24种;害虫优势种为棉蚜、烟粉虱、棉叶螨、棉盲蝽;捕食性天敌优势种主要为四点亮腹蛛、龟纹瓢虫、T-纹豹蛛、草间小黑蛛、八斑球腹蛛、华姬猎蝽、小花蝽、青翅隐翅虫。该区棉田害虫与捕食性天敌在棉株上的分布特点为:四点亮腹蛛、T-纹豹蛛、草间小黑蛛、八斑球腹蛛、小花蝽、青翅隐翅虫为下部>中部>上部;烟粉虱、棉盲蝽为上部>中部>下部;华姬猎蝽7月30日前为上部>下部>中部,8月9日后为下部>上部>中部;棉蚜在6月20日前为上部>下部>中部,在6月30日后为下部>上部>中部;棉叶螨前期主要分布在下部,后期向上转移;龟纹瓢虫在7月10日前为上部>中部>下部,7月20日之后为下部>上部>中部。群落均匀度在棉花生长发育前期较低,中期逐渐上升,后期又逐渐下降;集中度的变化趋势与均匀度相反;多样性在棉花生育中期最高。以物种为单位和以功能团为单位的群落多样性指数和均匀度指数呈高度正相关,相关系数(r)为0.9904。     

基于地统计学和GIS的化学农药胁迫下桃树桃蚜与草间钻头蛛种群空间格局

化学农药过量施用不仅杀死了害虫和自然天敌,也影响天敌与害虫之间的空间关系。桃园生态系统中草间钻头蛛(Hylyphantes graminicola)是桃蚜(Myzus persicae)的重要捕食性天敌,本文系统调查了化学农药长期胁迫下不同时期(4月中旬至9月上旬)桃树桃蚜和草间钻头蛛种群数量,并运用地统计学方法和地理信息系统(GIS)分析了桃树桃蚜和草间钻头蛛种群的空间结构,并采用基于高斯模型、指数模型、球型模型和圆型模型的普通克立格插值法模拟了其种群空间分布格局。结果表明,桃蚜和草间钻头蛛种群在10次调查期间均呈随机分布格局;桃蚜和草间钻头蛛空间分布距离相关性较弱,其变动范围均为6.863 0~43.174 1 m;桃蚜和草间钻头蛛的空间结构比例分别为0.788 8~0.983 9和0.811 6~0.980 6,块金值分别为0.254 2~4.896 3和0.218 4~0.749 9,偏基台值分别为0.010 5~0.250 0和0.004 8~0.075 7。本研究结果显示,长期使用化学农药致使桃树桃蚜和草间钻头蛛种群的空间结构比例值均大于0.7500,这表明化学农药胁迫下桃蚜和草间钻头蛛种群之间的跟随效应不明显,草间钻头蛛对桃蚜的捕食作用不强。     

广西球蛛记述

本文报道了广西农田、果园18种球蛛,其中5个新种和2个国内新记录种,分属8个属,并对新种和国内新记录种作了记述。     

广西蜘蛛名录(Ⅳ)

报道广西蜘蛛目（Araneae)35科76属136种，补充报道跳蛛科（Salticidae)8种，园蛛科（Araneidae)24种，狼蛛科（lycosidae)7种，球蛛科（Theridiidae)17种，肖蛸科（Tetragnathidae)2种，并分别列出各种蜘蛛的地理分布和生境。     

虎纹捕鸟蛛毒素的提取及毒力的测定

报道了提取广西产虎纹捕鸟蛛 (Selenocosm ia huw ena) 毒素的方法。用冻干蛛毒对小鼠进行腹腔注射, 测定出虎纹捕鸟蛛毒素的LD50 为0.77 m g/kg, LD50的95% 可信限为0.72～0.82 m g/kg, 表明该毒素有很强的毒力。并观察到当用0.30 m g/kg 冻干蛛毒注射小鼠颅内时, 小鼠迅速抽搐5 s后即死亡     

低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响

【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。     

Pasture Vegetation Elemental Analysis by Laser-Induced Breakdown Spectroscopy

Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.     

Faculty positions:Center for Agricultural Resources Research,Chinese Academy of Sciences

正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,     

Biodiversity and ecogeography of wild Lactuca spp. in some European countries

Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.     

Macroinvertebrates in North American tallgrass prairie soils: effects of fire, mowing, and fertilization on density and biomass

The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.     

Properties of anaerobically digested and composted municipal solid waste assessed by linking soil mesofauna dynamics and nitrogen modelling

We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass, soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration, N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially (<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils, indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea.     

Faculty positions: Center for Agricultural Resources Research,Chinese Academy of Sciences

正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,     

Faculty positions: Center for Agricultural Resources Research,Chinese Academy of Sciences

正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,     

Variation in quality parameters between and within 14 Nordic tree fruit and berry species

Abstract

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species.     

Potassium Fixation and Release Characteristics in Rhizosphere and Nonrhizosphere Soils for a Rapeseed–Rice Cropping Sequence

Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L^?1 nitric acid (HNO₃) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L^?1 ammonium acetate (NH₄OAc) and 1.0 mol L^?1 HNO₃ extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils.