The Future of Cydia pomonella Granulovirus in Biological Control of Codling Moth

Resistance of codling moth against Cydia pomonella granulovirus (CpGV) products has alarmed growers, extension services, the CpGV producers and the scientific community. During the last two years many activities were initiated in Germany and in Europe to understand this phenomenon and to overcome this problem. Meanwhile, first important results about the distribution, mode of inheritance and the efficacy of novel CpGV isolates overcoming CpGV resistance became available. This contribution will provide an overview about the different developments and the progress made towards an improvement of CpGV application in the future

What do we (need to) know about low-susceptibility of codling moth against Cydia pomonella granulovirus (CpGV)!

In 2005, the first codling moth (CM) populations with a reduced susceptibility to Cydia pomonella granulovi-rus (CpGV) products have been observed. This phenomenon might be an indicator of an emerging resis-tance of CM to CpGV. This paper summarizes some aspects of CM CpGV interaction and discusses poten-tial mechanisms in the host virus interaction, which could contribute to the observed low susceptibility. In order to develop and implement successful resistance management strategies, much more knowledge about the plasticity of CM CpGV interaction and the diversity of CM populations is essential

AFLPs: genetic markers for paternity studies in newts (Triturus vulgaris)

DNA-based genetic markers can reveal paternity whenever the direct assignment of fathers to offspring is precluded by multiple matings and internal fertilisation. Microsatellites are the current marker of choice in many behavioural studies, and have revealed important insights into genetic mating systems of European amphibians. However, the number of amphibian species for which the time-consuming designing of locus-specific microsatellite primers was successful is still limited, and the cross-utilisation of existing markers to closely related taxa seems to have a particularly low success rate. Allozymes can infer parentage without a species-specific protocol, but, due to their low degree of polymorphism, in mate choice experiments require the a priori screening of individuals. Dominant markers such as RAPDs successfully identified closely-related amphibian species and their hybrids, but might be less suited to distinguish between closely related individuals with a putatively high frequency of shared bands

What do we (need to) know about low-susceptibility of codling moth against Cydia pomonella granulovirus (CpGV)!

In 2005, the first codling moth (CM) populations with a reduced susceptibility to Cydia pomonella granulovirus (CpGV) products have been observed. This phenomenon might be an indicator of an emerging resistance of CM to CpGV. This paper summarizes some aspects of CM CpGV interaction and discusses potential mechanisms in the host virus interaction, which could contribute to the observed low susceptibility. In order to develop and implement successful resistance management strategies, much more knowledge about the plasticity of CM CpGV interaction and the diversity of CM populations is essential

On the Geometry of Constant Returns

Constant returns to scale, always a simplifying assumption, is often also much more: many important results depend critically on the very special properties of this class of production function. This paper provides a unified set of simple proofs for most of the crucial analytical properties of constant returns production and their implications for firm costs. Only familiar diagrams and high school geometry are used, and the proofs are written to be easily accessible to college sophomores.

Masses and Interactions of q-Fermionic Knots

The q-electroweak theory suggests a description of elementary particles as solitons labelled by the irreducible representations of SU_q(2). Since knots may also be labelled by the irreducible representations of SU_q(2), we study a model of elementary particles based on a one-to-one correspondence between the four families of Fermions (leptons, neutrinos, (-1/3) quarks, (2/3) quarks) and the four simplest knots (trefoils). In this model the three particles of each family are identified with the ground and first two excited states of their common trefoil. Guided by the standard electroweak theory we calculate conditions restricting the masses of the fermions and the interactions between them. In its present form the model predicts a fourth generation of fermions as well as a neutrino spectrum. The same model with q almost equal to 1 is compatible with the Kobayashi-Maskawa matrix. Depending on the test of these predictions, the model may be refined.Comment: 40 pages, 2 figures, latex forma

Skin swabs with FTA® cards as a dry storage source for amphibian DNA

Amphibians are the most endangered group of vertebrates, and conservation measures increasingly rely on information drawn from genetic markers. The present study explores skin swabs with Whatman FTA® cards as a method to retrieve PCR-amplifiable amphibian DNA. Swabs from ten adult great crested newts (Triturus cristatus) were used to compare FTA® card-based protocols with tissue sampling based on toe clips. PCR success rates were measured for seven microsatellite markers and one mtDNA marker (ND4) after 6 months of sample storage. We demonstrate that the merging of eight FTA® card punches from Qiagen-based DNA extraction always led to successful amplifications in at least one replicate, at an overall PCR success rate of 78%. The newly established protocol has the potential for wide application to future DNA-based amphibian studies

Do fringe benefits cause layoffs?

It is commonly believed that firms prefer layoffs to worksharing, in part, because layoffs economize on fringe benefit costs. We find that when labor markets are characterized by optimal implicit contracts, layoffs will never occur in equilibrium, regardless of the level of fringe benefits

Differential response at the seafloor during Palaeocene and Eocene ocean warming events at Walvis Ridge, Atlantic Ocean (ODP Site 1262)

The Latest Danian Event (LDE, c. 62.1 Ma) is an early Palaeogene hyperthermal or transient (<200 ka) ocean warming event. We present the first deep-sea benthic foraminiferal faunal record to study deep-sea biotic changes together with new benthic (Nuttallides truempyi) stable isotope data from Walvis Ridge Site 1262 (Atlantic Ocean) to evaluate whether the LDE was controlled by similar processes as the minor early Eocene hyperthermals. The spacing of the double negative δ13C and δ18O excursion and the slope of the δ18O–δ13C regression are comparable, strongly suggesting a similar orbital control and pacing of eccentricity maxima as well as a rather homogeneous carbon pool. However, in contrast to early Eocene hyperthermals, the LDE exhibits a remarkable stability of the benthic foraminiferal fauna. This lack of benthic response could be related to the absence of threshold-related circulation changes or better pre-adaptation to elevated deep-sea temperatures, as the LDE was superimposed on a cooling trend, in contrast to early Eocene warming