Assessing cetacean body condition: Is total lipid content in blubber biopsies a useful monitoring tool?

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Pathotypes of <Emphasis Type="Italic">Plasmodiophora brassicae</Emphasis> causing damage to oilseed rape in the Czech Republic and Poland

Winter oilseed rape (Brassica napus) is an important crop in the Czech Republic and Poland. Clubroot disease caused by the pathogen Plasmodiophora brassicae is a serious and still-growing problem for oilseed rape growers in both countries. The aim of this study was to evaluate the pathotype composition of P. brassicae populations from the Czech Republic and Poland, according to the three evaluation systems, and to determine soil inoculum loads for representative fields via traditional end-point PCR as well as quantitative PCR analysis. There were considerable differences between the populations of P. brassicae from both countries, and the number of pathotypes varied depending on the evaluation system and the threshold used to distinguish susceptible vs. resistant plant reactions. This is the first study comparing the effect of different thresholds. Using an index of disease (ID) of 25 % to distinguish susceptible vs. resistant reactions, there was a total of seven pathotypes identified based on the differentials of Williams, five with the system of Somé et al., and 18 with the European Clubroot Differential (ECD) set. However, based on a threshold of 50 %, there were nine pathotypes according to the evaluation system by Williams, four based on the differentials of Somé et al., and 15 with the ECD set. Changing of the thresholds led to the reclassification of some pathotypes. Several pathotypes were common in both countries. High amounts of pathogen DNA were found in many of the field soils analysed by quantitative PCR. There was a weak correlation between soil pH and infestation of P. brassicae for the Polish soils.     

Studies on the Physiology of Hyacinth Bulbs Hyacinthus Orientalis L. I. Sugar Content and Metabolic Activities in Bulbs Exposed to Low Temperatures

Changes in the content of carbohydrates and in the activity of hydrolytic enzymes were studied in hyacinth bulbs exposed to low temperatures. It was found that the amount of insoluble carbohydrate initially present in the scales and buds of hyacinth bulbs decreased greatly after a prolonged period of low temperature treatment. This decrease was greater in rooted bulbs, held at a low temperature for 63 days in natural conditions, than in unrooted bulbs stored in a refrigerator for the same period. At the same time the levels of soluble mono- and oligosaccharides, and of soluble starch, increased in the scales and buds of chilled bulbs. These changes in sugar level were found to be correlated with changes in the activity of certain hydrolytic enzymes. The activity of these enzymes was higher in rooted bulbs than in those which had not rooted before treatment. The activity of hydrolytic enzymes was found to be considerably higher in the flower buds than in the scales.     

An inventory of recent innovations in fruit and fruit products

Summary

The goals of this study were to make an inventory of recent and ongoing fruit and fruit product innovations, to assess what novelty or improvement they offer, and whether consumers could identify and/or recognise them. Researchers from 11 European countries submitted 386 examples of fruit and fruit product innovations. The list of innovations obtained has been coded, categorised, sorted, and reduced in subsequent stages. First, the examples received were categorised according to the Oslo Manual definitions. Second, product and marketing innovations were selected, as they are the only ones that were likely to be recognised by consumers. Next, analysis revealed that the novelties these innovations offered related to Convenience, Health, Differentiation, Target Group, Information, Sensory Characteristics, In Home and/or Out of Home Quality. Some innovations offered only one novel aspect, whereas others offered multiple aspects. Interrelationships between novel aspects are discussed for those innovations that offered a combination of aspects.     

Functional response of <Emphasis Type="Italic">Quercus robur</Emphasis> L. to taproot pruning: a 5-year case study

Key message

Quercus robur seedling mass was affected more by planting density than by taproot pruning. Root pruning enhanced stem biomass at the expense of roots in later growth stages. Alteration of biomass allocation due to nursery practices may result in greater susceptibility to injury and death of the seedlings under unfavorable environmental conditions.

Context

Plants adjust their growth and modulate the resource allocation in response to applied treatments and environmental conditions.

Aims

The aim was to examine how taproot pruning in seedlings grown at different densities affected long-term growth of Quercus robur.

Methods

Seedlings, sown as acorns at two planting densities, with or without pruned roots were harvested in the second, fourth, and fifth years of growth. The effect of root pruning on biomass allocation was determined by measuring leaf, stem, and root mass fractions; carbohydrate concentrations in the roots; and C/N ratios. Specific leaf area and root length were also determined to assess morphological adaptations to growth conditions.

Results

Total seedling mass was affected more by planting density than by taproot pruning. After 4 years of growth, root mass fractions were lower and stem mass fractions were greater in seedlings planted at a higher density. Five-year old root-pruned seedlings also had a lower root mass fraction and higher stem mass fractions than unpruned seedlings. Specific root length was not affected by root pruning or planting density.

Conclusion

Decrease of relative root biomass with simultaneous increase of stem biomass may be a long-term consequence of taproot pruning of Q. robur, and the effects may manifest years after the seedling stage.

     

Ultrastructural morphologic evaluation of the phenotype of valvular interstitial cells in dogs with myxomatous degeneration of the mitral valve

OBJECTIVE: To evaluate morphologic changes in valvular interstitial cells of dogs and to find evidence for disease-associated phenotypic changes in these cells. ANIMALS: 5 clinically normal dogs and 5 dogs with severe mitral valve endocardiosis. PROCEDURE: Mitral valve leaflets were evaluated by use of transmission electron microscopy. Differences in cell type and cell location were identified. RESULTS: A change in cell type toward a myofibroblast or smooth muscle cell phenotype was detected, with the smooth muscle cell type being most common. These cells had long amorphous cytoplasmic extensions, fibrillar cytoplasm, incomplete basal lamina, few mitochondria, and eccentrically placed nuclei but lacked smooth endoplasmic reticulum or Golgi complexes. Remaining valvular interstitial cells had heterochromatic nuclei and produced only minimal quantities of collagen. Compared with normal valves, myxomatous valves ha many interstitial-like cells located adjacent to the endothelium. Deeper within the abnormal valves, cells with a heterogenous phenotype formed groupings that appeared to be anchored to adjacent collagen. CONCLUSIONS AND CLINICAL RELEVANCE: Myxomatous degeneration of the mitral valve in dogs is associated with phenotypic alteration, changing from an interstitial to a mixed myofibroblast or smooth muscle cell phenotype. A closer association between interstitial cells and the endothelium is evident in diseased valves. In response to the disease process, valvular interstitial cells of dogs appear to change toward a smooth muscle phenotype, possibly in an attempt to maintain valve tone and mechanical function.     

Massive-star supernovae as major dust factories

We present late-time optical and mid-infrared observations of the Type II supernova 2003gd in the galaxy NGC 628. Mid-infrared excesses consistent with cooling dust in the ejecta are observed 499 to 678 days after outburst and are accompanied by increasing optical extinction and growing asymmetries in the emission-line profiles. Radiative-transfer models show that up to 0.02 solar masses of dust has formed within the ejecta, beginning as early as 250 days after outburst. These observations show that dust formation in supernova ejecta can be efficient and that massive-star supernovae could have been major dust producers throughout the history of the universe.