Identifying global centers of genetic diversity for grain sorghum with the use of rice DNA markers

STS and InDel markers developed on the basis of DNA sequences of certain rice genes are used for a comparative study of grain sorghum accessions. The main sorghum genetic diversity centers are revealed, two in Africa and a third in regions of Central, East, and South Asia.     

Progressive axonopathy: an inherited neuropathy of Boxer dogs. 1. Further studies of the clinical and electrophysiological features

The clinical and electrophysiological findings in 14 Boxer dogs with progressive axonopathy (PA) are described. The salient clinical features are hind-limb ataxia which may later involve forelegs, proprioceptive defects, hypotonia, patellar areflexia, absence of muscle atrophy and, in a few instances, ocular tremor and head bobbing. The outward signs are often observed by 2–3 months of age but clinical testing can reveal patellar areflexia at 1 month of age. After an initial progression, the signs may stabilize and dogs are alive at 4 years of age having shown no deterioration over the previous 2 years. The electrophysiology shows reduced motor nerve conduction velocities and evoked potential amplitudes after about 4 months of age. The F-wave latency is considerably increased. Sensory nerves also show a marked reduction in the amplitude of their evoked potentials and eventually cease to conduct. Abnormal spontaneous activity is not a feature on electromyography. The conduction defects probably reflect to some degree the reduced nerve fibre diameters and myelin sheath changes found in PA although other factors may also be operating. The study shows that PA can be diagnosed with reasonable confidence by routine clinical testing at an early age.     

Identifying new volatile compounds in toasted oak

Toasting wood to be used in barrels for aging wine produces a great number of volatile and odiferous compounds. Three new volatile odorous compounds in toasted oak were identified. Analysis by high-performance gas chromatography of toasted oak extracts, combined with olfactory detection, enabled various chromatographic peaks with these specific aromas to be isolated. These same odors were simultaneously studied by heating glucose both with and without proline and phenylalanine. Aromatic compounds of interest were identified thanks to a combination of gas chromatography and both mass and infrared spectrometry. An analysis RMN was also used. Hydroxymaltol, 2,5-furanedicarbaldehyde, and furylhydroxymethyl ketone have been detected in extract of toasted oak wood. These molecules may be formed by direct pyrolysis of sugar or Maillard reactions. The acetylformoine was not detected in extract of toasted oak wood, whereas it was detected in heated extracts of various sugars and sugars mixtures with amino acids.     

Intrauterine Neospora caninum inoculation of heifers

Here, we studied the potential of Neospora caninum tachyzoites to infect heifers when administered in utero by artificial insemination via contaminated semen. Eighteen primiparous cyclic heifers were hormonally synchronized and artificially inseminated. Nine of them, which were inseminated with semen containing 10(7) live N. caninum NC-1 isolate-tachyzoites, reacted with seroconversion and a specific IFN-gamma response. Moreover, N. caninum DNA was demonstrated by a nested-PCR in the blood of all nine heifers and in brain, lungs, liver and uterine horn of several of them. In contrast, nine heifers inseminated with tachyzoite-free semen developed no antibody or IFN-gamma responses, and no parasite DNA was detected in blood or organs. At necropsy, viable embryos were detected in one and six of the infected and non-infected heifers, respectively. No specific Neospora DNA was detected in any of the embryos. This study provides evidence that intrauterine inoculation via contaminated semen cause N. caninum infection in cattle.     

A population of murine gammadelta T cells that recognize an inducible MHC class Ib molecule

Although gammadelta T cells are implicated in regulating immune responses, gammadelta T cell-ligand pairs that could mediate such regulatory functions have not been identified. Here, the expression of the major histocompatibility complex (MHC) class Ib T22 and the closely related T10 molecules is shown to be activation-induced, and they confer specificity to about 0.4% of the gammadelta T cells in normal mice. Thus, the increased expression of T22 and/or T10 might trigger immunoregulatory gammadelta T cells during immune responses. Furthermore, the fast on-rates and slow off-rates that characterize this receptor/ligand interaction would compensate for the low ligand stability and suggest a high threshold for gammadelta T cell activation.     

Ecotypes of Italian ryegrass from Swiss permanent grassland outperform current recommended cultivars

Italian ryegrass (Lolium multiflorum Lam. ssp. italicum Volkart ex Schinz et Keller) thrives well in permanent grassland in mild and moist regions of Switzerland. Ecotypes of Italian ryegrass from Swiss permanent meadows have often been used successfully as the base material of breeding programmes. However, their agronomic performance per se has never been studied in detail. Therefore, field trials were conducted to assess the potential of this semi-natural genetic resource for use in breeding. Twenty ecotype populations were collected in different geographical regions in 2003 and seed was increased. Plot trials with 20 ecotype populations were conducted 2005–2007 at three locations, supplemented by row trials at two additional locations, and including four currently recommended cultivars as controls. Average performance in terms of yield, vigour and resistance to snow mould of ecotypes was superior to the cultivars. Depending on the characteristic, between three and 16 of the 20 ecotypes performed significantly better than the cultivars mean. However, resistance against crown rust of all ecotypes was significantly poorer than that of the cultivars. Correlation and regression analysis showed that more eastern and more northern collecting sites harboured better performing ecotypes. However, the most consistent site related factor favouring performance of the ecotypes in terms of yield, vigour, snow mould and Xanthomonas resistance was a low abundance of species which are typical of Arrhenatheretum type meadows. Data from the plot trials were related to results obtained with spaced plants at a single site, either in a seedling nursery or in the greenhouse. Resistance against crown rust was extremely well predicted by spaced plant observations. Xanthomonas resistance observed after artificial inoculation in the greenhouse was also significantly, but less closely correlated with field observations. An early date of ear emergence as observed on spaced plants was associated with high annual yield in the plot trials. It is concluded that in intensively managed habitats, natural selection has resulted in ecotype populations of Italian ryegrass which are highly promising for use in breeding. Individual plant selection for resistance can be expected to efficiently reduce their high susceptibility to crown rust.     

Scanning study of the optical parameters of sandy soddy-steppe soil samples from the southern Ukraine

It was shown that an office scanner can be used for the acquisition of digital images of soil samples and their analysis using the RGB color system. The content and optical density of the humic acids were the main factors determining the color intensity of sandy soils. With all the other factors being constant, the increase in the content of clay particles resulted in a decrease in the color intensity of the sandy soils, whereas a decrease in the content of the coarse sand increased the color intensity. The content of mobile iron had the least significant effect on the color of the sandy soils.