Evaluation of Steinernema carpocapsae Weiser for Control of Carrot Weevil Adults, Listronotus oregonensis (LeConte) (Coleoptera: Curculionidae), in Organically Grown Carrots

Under controlled conditions, application of Steinernema carpocapsae using a baiting method consistently reduced the oviposition of Listronotus oregonensis adults at all moisture regimens. At 80 and 95% relative humidity, soil applications at 10 4 infective juveniles (IJs) cm-2 and 10 5 infective stages (400 IJs cm-2) per pot reduced the survival and oviposition of L. oregonensis adults; soil applications were ineffective at relative humidity lower than 80%. When timed correctly, soil application at the rate of 2 105 IJs/linear meter of row (4.4 109 IJs ha-1) reduced damage by up to 59%.     

Outgroup heteroduplex analysis using temperature gradient gel electrophoresis: high resolution, large scale, screening of DNA variation in the mitochondrial control region

The ability of DNA screening techniques such as Temperature Gradient Gel Electrophoresis (TGGE) and Heteroduplex Analysis to provide resolution approaching that provided by DNA sequencing for a fraction of the time, effort and expense point to them as the logical successor to allozyme electrophoresis for population genetics. Here we present a novel alternative to the standard TGGE/Heteroduplex Analysis protocol - Outgroup Heteroduplex Analysis (OHA). We assess this technique's sensitivity in comparison to previous screening approaches using a known hierarchy of sequence differences. Our data show that Outgroup Heteroduplex Analysis has greatly increased sensitivity for screening DNA variants from that of TGGE used alone and is easily applicable to large numbers of samples. Using this technique we can consistently detect differences of as small as one base change in a 433-base-pair fragment of Control Region mitochondrial DNA from Melomys cerbinipes (an Australian rodent). The approach should easily be extendable to nuclear loci and is not necessarily dependent on the use of a denaturing gradient When combined with a targeted sequencing effort, OHA provides a sensitive and simple means of obtaining allele/haplotype frequencies and their phylogenies for population and phylogeographic studies in molecular ecology.     

虎嘉鱼保护生物学的研究V.生境特点及保护对策

本文报道了虎嘉鱼的生境特点及保护对策,主要是加强宣传教育,严禁滥捕,深入研究,开展人工养殖试验和建立自然保护区等措施,确保物种生存和繁衍。     

Effects of inorganic amendments (N,P and K) to soil on the rhizosphere microflora of antirrhinum plants infected withVerticillium dahliae Kleb

Summary A study of the inorganic amendments (N, P and K) to soil, and their effect on the rhizosphere microflora, as well as their relation to the control of wilt of antirrhinum plants caused byVerticillium dahliae Kleb. was done. Ammonium sulphate was the only chemical found to be significantly inhibitory toV. dahliae in vitro. Soil amendments (NPK) affected the rhizosphere microorganisms of the antirrhinum plants. Higher concentration of the chemicals were phytotoxic. It was further observed that ammonium sulphate, and the combined chemicals (NPK 25%) in soil delayed the senescence in healthy plants, suggests that chemical fertilisers affected the host plants directly. Addition of ammonium sulphate (0.25%), calcium nitrate (0.25%, 0.5%) combined NPK (0.25%) to soil caused considerable reduction in disease severity. It is assumed that this reduction may be caused by the (1) fungitoxic nature of the chemicali.e. ammonium sulphate, (2) antagonistic environment for the pathogen in the rhizosphere was boostedi.e. where calcium nitrate was added as soil amendments and (3) reduction in disease severity in soil-amended with combined NPK, may be due to the fact that antagonistic actinomycete population was boosted in the rhizosphere.     

Graphical comparison of resemblance measures in phytosociology

A simple graphical method, COREM, is described for the comparison of quantitative resemblance measures. The basis of the method is the ordered comparison case series (OCCAS) composed of relevé pairs ranked in decreasing order of similarity. For a given OCCAS, values of given resemblance functions are calculated and plotted in COREM.Delta resemblance (DR) is defined as the rate of change between two neighbouring relevé pairs in the OCCAS. High mean delta resemblance (% MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqaqpepeea0xe9qqVa0l% b9peea0lb9sq-JfrVkFHe9peea0dXdarVe0Fb9pgea0xa9pue9Fve9% Ffc8meGabaqaciGacaGaaeqabaWaaeaaeaaakeaadaqdaaqaaGqaai% aa-reacaWFsbaaaaaa!392E!\[\overline DR \]) of a resemblance measure indicates a high power of resolution and small standard deviation (SDDR) is indicative of linearity. A measure of efficiency combines % MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqaqpepeea0xe9qqVa0l% b9peea0lb9sq-JfrVkFHe9peea0dXdarVe0Fb9pgea0xa9pue9Fve9% Ffc8meGabaqaciGacaGaaeqabaWaaeaaeaaakeaadaqdaaqaaGqaai% aa-reacaWFsbaaaaaa!392E!\[\overline DR \] and SDDR in the coefficient of variation for delta resemblance (CVDR). An efficient measure shows balanced sensitivity to the common and differential species. With the method COREM locally optimal resemblance measures may be selected for any given set of relevés which produce the sharpest separation of clusters. A reasonable compromise is to use types of measures, such as the similarity ratio (SIM6), Czekanowski coefficient (SIM8), or floristic similarity (SIM9), which have the best chance of being successful in most relevé sets. A study of transformation functions on Braun-Blanquet values with the help of COREM demonstrates that the combined transformation is the most advantageous for clustering. It is shown that standardization by relevés, or conversion to unit sum has undesirable effects.During the preparation of this paper the author was a recipient of a Postgraduate Scholarship, Deutscher Akademischer Austauschdients, Dortmund, KFA Abteilung Algenforschung, Germany. The author would like to thank L. Orlóci, P. Juhász-Nagy and E. van der Maarel for valuable suggestions, and comments.     

A review of assessment and remediation strategies for hat spot sediments

Sediments at the extreme end of the scale of contamination, designated as hot spot sediments, are considered. The characterization of such hot spots, and an approach for the quantitative assessments of the behaviour and fate of pollutants in such sediments are covered. Experiments with sediments containing extreme levels of heavy metals showed release rates of 56 mg m^–2 d^–1 of dissolved zinc and 0.004 mg m^–2 d^–1 of dissolved mercury. When these sediments were resuspended, the dissolved fluxes were increased by a factor of 2.2 and 128 for zinc and mercury, respectively. The biological implications of hot spot sediments are dealt with, since sediments are an important habitat for many organisms. Various alternatives for clean-up operations including dredging and capping are discussed.     

Morphological and ultrastructural variations inAzotobacter vinelandii growing in oxygen-controlled continous culture

Membrane development as a response to growth at different oxygen tensions (from about 1% to 100% saturation of the medium with air) was determined inAzotobacter vinelandii strain OP. The organisms were grown in a carbonlimited chemostat either on atmospheric nitrogen or on ammonium as nitrogen sources. Both types of cultures increased not only the number of intracytoplasmic membrane vesicles per cell but also the cell volume with aeration. As the ratio of length per width stayed largely constant increases of volume resulted in decreases of the cell surface area, representing the surface area of the peripheral cytoplasmic membrane, per cell volume. While in nitrogen-fixing cells the proportion of intracytoplasmic membrane surface area per cytoplasmic membrane surface area increased from 1:2 to 3:1 the ratio stayed almost constant in ammonium-assimilating cells. The data suggest that oxygen controls changes in the ratio of intracytoplasmic to cytoplasmic membrane surface areas only under conditions of nitrogen fixation.Abbreviations CM Cytoplasmic membrane - ICM intracytoplasmic membrane     

Genomic architecture of autism from comprehensive whole-genome sequence annotation

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