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An heterogeneous population of oocytes is usually collected from ovaries to be used f or several in vitro techniques. Sources of variability may be the age of oocytes, their growth stage, and the apoptosis grade. All these factors might affect an efficiency of in vitro embryo production. Although recently the new selection methods have been introduced, the in vitro embryo production efficiency does not exceed 40%. Much research is being done to determine the useful markers of oocyte developmental competence. The present review briefly describes selected biochemical and molecular markers. Subsequently the status of the members of Bcl-2 family proteins and the caspases (molecular markers) expression and their function in orchestrating cell death in oocyte and embryo were considered.
Most common approach to interpretation of genotype-environment interaction (GxE interaction) for breeding and variety recommendation purposes is stability and adaptation analysis of genotypes in a target region of cultivation. The aim of this paper was to review very rich both scientific and practical achievements in statistical methodology of stability and adaptation analysis of genotypes. The methods used could be divided into three groups: univariate parametric methods, univariate nonparametric methods and multivariate methods. Most of the methods are based on both fixed and mixed linear and multiplicative models. Stability measures defined in many models are useful to evaluating similarity of a genotype trait response to environmental conditions in a target region to a norm (concept) of dynamic (agronomic) stability which has been introduced by Becker and Leon (1988). Joint regression models belong to those most of ten used in considered studies. Recently, multivariate models and methods have become a standard statistical tool in interpreting GxE interaction for various purposes. They are extensions of the conventional joint regression models, both fixed and mixed ones. Among them, AMMI models and related methods have been most effective and, then of ten used in field experimentation. The AMMI models incorporate both additive and different kinds of multiplicative components. Some parametric and nonparametric criteria, incorporating both yield-means and yield-stability measures can be effective to selecting such genotypes which productivity in a target region indicates their wide adaptation.
Each generation of Blattella germanica were treated with a dose of 0.42 μg permethrin per VI instar larva. The fecundity varied from 8.21 to 33.66 for I instar larvae per female. Reproduction was significantly lower than that evaluated for untreated insects in third and fourth generations, but significantly higher in the fifth generation. Mortality among insects treated with permethrin, with the exception of the fourth generation only, was higher than among untreated cockroaches. In the third; fourth and fifth generations, the biotic potential was significantly lower in groups of treated insects than in untreated ones. The length of the developmental period of B. germanica treated with permethrin, measured during 7 generations, showed no significant changes in comparison with the control groups.
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