Evolution of Fusarium oxysporum f. sp. vasinfectum Races Inferred from Multigene Genealogies

ABSTRACT Fusarium wilt of cotton is a serious fungal disease responsible for significant yield losses throughout the world. Evolution of the causal organism Fusarium oxysporum f. sp. vasinfectum, including the eight races described for this specialized form, was studied using multigene genealogies. Partial sequences of translation elongation factor (EF-1alpha), nitrate reductase (NIR), phosphate permase (PHO), and the mitochondrial small subunit (mtSSU) rDNA were sequenced in 28 isolates of F. oxysporum f. sp. vasinfectum selected to represent the global genetic diversity of this forma specialis. Results of a Wilcoxon Signed-Ranks Templeton test indicated that sequences of the four genes could be combined. In addition, using combined data from EF-1alpha and mtSSU rDNA, the phylogenetic origin of F. oxysporum f. sp. vasinfectum within the F. oxysporum complex was evaluated by the Kishino-Hasegawa likelihood test. Results of this test indicated the eight races of F. oxysporum f. sp. vasinfectum appeared to be nonmonophyletic, having at least two independent, or polyphyletic, evolutionary origins. Races 3 and 5 formed a strongly supported clade separate from the other six races. The combined EF-1alpha, NIR, PHO, and mtSSU rDNA sequence data from the 28 isolates of F. oxysporum f. sp. vasinfectum recovered four lineages that correlated with differences in virulence and geographic origin: lineage I contained race 3, mostly from Egypt, and race 5 from Sudan; lineage II contained races 1, 2, and 6 from North and South America and Africa; lineage III contained race 8 from China; and lineage IV contained isolates of races 4 and 7 from India and China, respectively.     

Field trial of a staphylococcal mastitis vaccine in dairy herds: clinical, subclinical and microbiological assessments

Objective To assess the efficacy of a new staphylococcal mastitis vaccine under commercial dairying conditions.
Design A field trial involving 1819 cows and heifers conducted on seven dairy herds in Victoria. The trial was done 'blind'; approximately half the animals were vaccinated and the remainder were untreated controls.
Procedure The vaccine was given twice during the last 10 weeks of pregnancy. Effects of vaccination were assessed, during the ensuing lactation, on the basis of clinical and sub-clinical mastitis and microbiological investigations of the milk.
Results A total of 273 cases of clinical mastitis were recorded. Staphylococcus aureus was isolated from 112 of these, 45 cases in vaccinates and 67 cases in controls; the difference was not statistically significant. One herd was notable in having a high incidence of clinical staphylococcal mastitis. This herd accounted for 15.8% of the animals in the field trial but 54.5% of cases of clinical staphylococcal mastitis. For this herd, vaccinated animals had significantly lower incidence of clinical staphylococcal mastitis and prevalence of subclinical mastitis, relative to controls. An unexpected feature of the trial as a whole was the low incidence of clinical mastitis from which S aureus was isolated in pure culture (26.3% of cases) and the high incidence of clinical Streptococcus uberis mastitis (22.7% of cases).
Conclusions The trial showed that the vaccine was efficacious in reducing the incidence of clinical mastitis and prevalence of subclinical mastitis in a herd that had a serious staphylococcal mastitis problem.     

优质蛋白玉米籽粒品质性状组间典型相关性研究

研究优质蛋白玉米籽粒品质性状组间典型相关性结果表明,2个半硬质胚乳奥帕克-2玉米群体(“中群14QPMC3”和“陕综5号QPMC0”)籽粒物理性状中硬质度、籽粒密度、百粒重与胚比、百粒体积呈负相关效应,营养品质中赖氨酸含量、蛋白质品质性状为其核心,籽粒密度(或硬质度)可作为蛋白质品质的间接选择指标;籽粒物理性状、蛋白质品质性状在赖氨酸产量构成中起决定性作用,全籽粒蛋白质品质与胚乳蛋白质品质紧密相关,而与胚蛋白质品质无关,高赖氨酸高油分育种相统一。     

anwendung der „vergleichsmethode standort (vermost)” zur bewertung der erosionsgefährdungspotenziale als datenbasis für förderinstrumente am beispiel des landes Brandenburg: Application of the site comparison method (vermost) to assess the potential erosion risk as a basis to examine instruments of environmental policy – the example of Brandenburg

This paper presents a comparative method (VERMOST) to evaluate complex site conditions at the level of a federal state (Brandenburg) and at different areal units. The methodology uses primary site conditions and provides the possibility to objectively compare and judge different ecological questions. Objects with heterogeneous content are pooled in comparison groups. Considering the main site characteristics allows a goal-oriented allocation of subsidies. The use of VERMOST is demonstrated for the wind and water erosion risk assessment across different scales from a federal state down to a parcel of land. The ‘parcel’ aggregation-level proves to be useful to assess the erosion risk. Larger scales are less useful in the assessment of subsidies policy with regard to erosion risk. A moving-window-technique combined with VERMOST is demonstrated to be suitable for comparing and assessing regional aspects more objectively compared with data administratively linked.     

Trichoderma brevicompactum complex: Rich source of novel and recurrent plant-protective polypeptide antibiotics (peptaibiotics)

Three strains of Trichoderma brevicompactum and another four that are closely related to that species (Trichoderma cf. brevicompactum) were analyzed for the formation of polypeptide antibiotics (peptaibiotics) by LC/ESI-MS(n). These isolates were selected because of an antagonistic potential against Eutypa dieback and Esca disease of grapevine and have not yet been investigated for the production of peptide antibiotics. Fully grown cultures on potato dextrose agar were extracted with CH2Cl2/MeOH, and this extract was subjected to SPE using C18 cartridges. The methanolic eluates were analyzed by LC/ESI-MS(n). All strains were found to produce membrane-active alamethicins F30. In addition to that, novel peptaibiotics were detected, namely, 14 12-residue trichocryptins B, 12 11-residue trichocryptins A, 19 11-residue trichobrevins A and B, 6 10-residue trichoferins, and 17 8-residue trichocompactins. These compounds may partially be responsible for the plant-protective action of the producers. Chemotaxonomic considerations also indicated the necessity to introduce another new species that is closely related to T. brevicompactum.     

Detection of alpha-transducin in retinal rods but not cones

The distribution in chicken retina of the alpha subunit of transducin, the guanine nucleotide--binding protein that couples light-dependent activation of rhodopsin with activation of guanosine 3',5'-monophosphate phosphodiesterase, was determined with the aid of a specific antiserum. alpha-Transducin was found in rod photoreceptor cells but was not detected in cones. These results show that rods and cones differ with respect to alpha-transducin content and suggest that the processes of phototransduction may differ correspondingly in rods and cones.     

Segmentation of Color Image Based on Feature Divergence and Fuzzy Theory

In order to improve general adaptive capability of algorithm,the new color image segmentation algorithm based on feature divergence and fuzzy theory(FDCIS) is proposed.The algorithm introduces feature divergence and fuzzy dissimilarity function into calculation in order to measure the dissimilarity of feature vector,clusters data by means of feature divergence,and accomplishes the merge of image region.The experimental results demonstrate that the color image segmentation result of the proposed approach reduce calculation on large sample of color image,simply and effectively solve over-segmentation of color image,avoid the dependence of the algorithm on initial condition,and hold favorable consistency in terms of human perception.     

Relationship Between Grain Yield and Yield Components in Super Hybrid Rice

Chinese super hybrid rice breeding project has developed many new varieties with great yield potential.It is controversial which yield component should be emphasized in super hybrid rice production.The present study was conducted to compare super hybrid rice with common hybrid and super inbred rice and analyze contributions of yield components to grain yield of super hybrid rice under experimental conditions,and evaluate relationships between grain yield and yield components of super hybrid rice in farmer's paddy fields.Field experiments were done in Changsha,Guidong,and Nanxian,Hunan Province,China,from 2007 to 2009.Eight super hybrid varieties,one common hybrid variety,and one super inbred variety were grown in each location and year.Rice production investigation was undertaken in high-yielding (Guidong),moderate-yielding (Nanxian),and low-yielding (Ningxiang) regions of Hunan Province,China,in 2009.Grain yield and yield components were measured in both the field experiments and rice production investigation.Super hybrid rice varieties outyielded common hybrid and super inbred varieties across three locations and years.Yield potential has been increased by 11.4％ in super hybrid rice varieties compared with common and super inbred varieties.The higher yield of super hybrid varieties was attributed to improvement in panicle size.Panicles per m2 had the highest positive contribution to grain yield with the exception under yield level of 10.0 to 12.0 t ha-1,and was positively related to grain yield in farmer's field at all of the high-,moderate-,and low-yielding regions.Our study suggests that panicle per m2 ought to be emphasized in super hybrid rice production.