Pollination dynamics in a Douglas-fir seed orchard as revealed by pedigree reconstruction

• ? Pollination dynamics was studied in a Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seed orchard using 8 nuclear microsatellite markers and pedigree reconstruction.
• ? The seed orchard consisted of 49 parents (clones). Cone-crop management included bloom delay and supplemental mass pollination (SMP) using 12 internal and 4 external pollen donors.
• ? A random sample of 801 bulk seeds was genotyped for both haploid megagametophyte and corresponding diploid embryo.
• ? Using the parental population’s multilocus genotypes, full pedigree reconstruction generated all the information needed to estimate the maternal, paternal, and parental reproductive success, selfing, pollen contamination, and pollination success of the 4 external pollen donors.
• ? Maternal, paternal, and parental reproductive success varied with 80% of gametes being produced by 23, 45, and 37% of the orchard’s parents, respectively, resulting in a drastically reduced effective population size as compared to the census number (14 vs. 53).
• ? Selfing, pollen contamination, and aggregate SMP success (internal and external) were estimated to be 15.2, 10.4, and 15.0%, respectively.
• ? Full pedigree reconstruction was effective in unraveling the orchard’s pollination dynamics and both female and male reproductive success.

     

Distribution of the double-spined spruce bark beetle <Emphasis Type="BoldItalic">Ips duplicatus</Emphasis> in the Czech Republic: spreading in 1997–2009

Ips duplicatus (Coleoptera: Curculionidae) was reported in the Euro-Siberian taiga from Sweden to Sakhalin and in the Alps at the beginning of the 20th Century. It has been recorded in spruce stands in the north-eastern part of the Czech Republic since the beginning of the 1970s; monitoring of I. duplicatus was conducted in the Czech Republic in 9 years between 1997 and 2009. Beetles of the overwintering generation were captured in Theysohn pheromone traps baited with a lure of ipsdienol and E-myrcenol, and after 2005 in ID Ecolure lures. Surprisingly, I. duplicatus was found throughout the Czech Republic already in 1997. In 2002, there was a nationwide decrease in their numbers. Particularly since 2005, there has been a spread from the main center of occurrence in the eastern areas to the south and west into the central part of Bohemia where, until that time, its population densities had been lower and had not caused economically significant damage. Moreover, it was observed that in the north-eastern parts of the Czech Republic up to 80% of spruce trees from sanitary felling had been infested by this pest in recent years. The recorded amount of spruce trees infested by I. duplicatus is correlated significantly with the amount of spruce trees recorded as damaged by Ips typographus, Ips amitinus and Pityogenes chalcographus infestation as well as with the numbers of individuals of I. duplicatus captured during the aforementioned monitoring.     

Influence of latent 'asymptomatic' toxoplasmosis on body weight of pregnant women

The latent toxoplasmosis is usually considered to be asymptomatic, however, this paradigm has never been rigorously tested. Here we searched for symptoms of deterioration of physical health (decrease of weight) in infected people by analysis of clinical records of 758 women tested for toxoplasmosis in the 16th week of gravidity. Toxoplasma-positive women have a lower body weight in the 16th week of gravidity (p = 0.02) than Toxoplasma-negative women. Moreover, a negative correlation between weight and the duration of toxoplasmosis was found in a subset of 174 Toxoplasma-positive women (p = 0.04), suggesting that slow and cumulative effects of latent toxoplasmosis, rather than a transient effect of acute toxoplasmosis, are responsible for the decreased weight of infected subjects. Longer duration of gravidity estimated from the date of last menstruation in the set of Toxoplasma-positive women in the 16th week of gravidity estimated with ultrasonography (p = 0.04) suggests a possibility of retarded foetal growth in Toxoplasma-positive women. The prevalence of latent toxoplasmosis is extremely high. Therefore, even its mild symptoms such as the decreased body weight in Toxoplasma-positive pregnant women might in fact indicate an unrecognized serious public health problem.     

Stripping Fecundity of Common Bream (Abramis brama L.) from the Rivers Trent and Sow (Nottinghamshire, UK)

Results obtained with common bream (Abramis brama) originating from the rivers Trent and Sow (Great Britain) are presented with particular attention to the egg size and absolute and relative fecundity recorded during stripping of hormonally (pituitary extract) treated females. The average number of eggs obtained by stripping 1 kg of female biomass (RSF) from the river Sow and Trent were 93,642 ± 20,896 and 151,179 ± 25,123, respectively. These values were similar to the respective parameters in bream populations from north-western USSR lakes.