Diversity,plant growth-promoting traits,and biocontrol potential of fungal endophytes of Sorghum bicolor

The diversity of fungal endophytes in Sorghum bicolor was investigated in samples collected from 10 different geographical regions of Karnataka state, India. A total of 360 endophytes were isolated from leaf, stem, and root tissues and were assigned to 26 fungal species based on morphology and molecular characterization using ITS sequences. All the endophytes belonged to the phylum Ascomycota. The diversity (Shannon H, 2.57; Simpson_1-D, 0.92) and species richness (Margalef's, 4.68; Menhinick, 3.61) were found to be higher for the endophytes isolated from leaf tissues. The species evenness of the endophytic assemblage was strongly influenced by tissue type, followed by geographical location. The biocontrol potential of isolated endophytes was evaluated against economically destructive sorghum grain mould pathogens such as Fusarium thapsinum, Epicoccum sorghinum, Alternaria alternata, and Curvularia lunata using the dual culture method. Biocontrol potential was exhibited by 26 endophytic isolates, of which Trichoderma asperellum recorded broad-spectrum activity against target pathogens, followed by E. nigrum and A. longipes. Most (82%) endophytes showed plant growth-promoting traits. Biosynthesis of indole-3-acetic acid (IAA) was observed in 84% of isolates, and phosphate solubilization, siderophore production, and cellulase activity was observed in 69%, 23%, and 27% of isolates, respectively. Seeds treated with T. asperellum exhibited a significantly higher seed vigour index (2096), germination percentage (94%), and yield under greenhouse and field conditions. The results were substantiated by the confocal microscopy analysis, which clearly demonstrated the colonization of treated endophyte in root tissues. The present study reveals an ecofriendly approach to explore T. asperellum in sorghum disease management.     

Impact of relationships between test and training animals and among training animals on reliability of genomic prediction

One of the factors affecting the reliability of genomic prediction is the relationship among the animals of interest. This study investigated the reliability of genomic prediction in various scenarios with regard to the relationship between test and training animals, and among animals within the training data set. Different training data sets were generated from EuroGenomics data and a group of Nordic Holstein bulls (born in 2005 and afterwards) as a common test data set. Genomic breeding values were predicted using a genomic best linear unbiased prediction model and a Bayesian mixture model. The results showed that a closer relationship between test and training animals led to a higher reliability of genomic predictions for the test animals, while a closer relationship among training animals resulted in a lower reliability. In addition, the Bayesian mixture model in general led to a slightly higher reliability of genomic prediction, especially for the scenario of distant relationships between training and test animals. Therefore, to prevent a decrease in reliability, constant updates of the training population with animals from more recent generations are required. Moreover, a training population consisting of less‐related animals is favourable for reliability of genomic prediction.     

Freezing cycles enhance winter injury in Picea rubens

We examined changes in chlorophyll absorbency in red spruce (Picea rubens Sarg.) foliage in response to simulated freezing cycles. Current-year branch tips were collected from 16 trees on January 8, January 20, February 8 and February 26, 1996. Tissue was subjected to freezing cycle treatments with a minimum of -35 degrees C and a maximum of 3 degrees C for a one-cycle treatment, and -9, -6, -3, 0 or 3 degrees C for four-cycle treatments. Samples were frozen at a rate of 5 degrees C h(-1), and warmed at 12 to 15 degrees C h(-1). Controls were held at -9 degrees C. Temperatures during the three-day periods preceding each sample date averaged -18, 4.7, -9.6 and 3.7 degrees C, respectively. On January 8, treated trees showed no significant (P > 0.1) increase in the breakdown of chlorophyll, as measured by the ratio of chlorophyll a absorbency (435 nm) to phaeophytin a absorbency (415 nm), compared with control branch tips. On later sampling dates, seven trees consistently exhibited needle reddening and nine exhibited few symptoms (< 10% of total needle surface reddened) after four-cycle treatments. On February 26, chlorophyll degradation in trees with needle reddening differed (P < 0.05) from the control by 26, 26, 16, 14 and 15% for the 3, 0, -3, -6 and -9 degrees C maxima, respectively. No detectable chlorophyll degradation occurred after a one-cycle treatment in any trees on any sampling date. Freezing cycles with sub-zero maxima and a -35 degrees C minimum enhanced winter injury in red spruce after a midwinter thaw had rendered the trees susceptible to freezing damage.     

Determination and depletion of residues of carbadox, tylosin, and virginiamycin in kidney, liver, and muscle of pigs in feeding experiments

The results of residue determinations of the growth promotors carbadox, tylosin, and virginiamycin in kidney, liver, and muscle from pigs in feeding experiments are described as well as the analytical methods used. Residues of the carbadox metabolite quinoxaline-2-carboxylic acid were found in liver from pigs fed 20 mg/kg in the diet with a withdrawal time of 30 days. No residues were detected in muscle with zero withdrawal time. The limit of determination was 0.01 mg/kg for both tissues. No residues of virginiamycin and tylosin were found in pigs fed 50 and 40 mg/kg, respectively, in the diet, even with zero withdrawal time. Residues of tylosin of 0.06 mg/kg and below were detected in liver and kidney from pigs fed 200 or 400 mg/kg and slaughtered within 3 h after the last feeding.     

Effects of Brussels sprout juice on the cell cycle and adhesion of human colorectal carcinoma cells (HT29) in vitro

Consumption of Brassica vegetables is associated with a reduced risk of cancer of the alimentary tract in animal models and human populations. We used raw juice extracted from Brussels sprouts rich in the glucosinolate sinigrin to explore the effect of naturally occurring glucosinolate breakdown products on cell cycle progression and apoptosis in human colorectal carcinoma cells (HT29). Juice was prepared from sprout tissue immediately before use, and the glucosinolate breakdown products were determined by gas chromatography mass spectrometry and liquid chromatography mass spectrometry. The cell cycle was analyzed by flow cytometry on detached and adherent cells, and apoptosis was measured in the detached population by annexin V staining. Twenty-four hours after challenge with juice (10 microL/mL), 7-13% of adherent cells had detached from the substratum but the majority (82%) of these cells had not entered apoptosis, whereas only 33% of detached control cells were not apoptotic (p < 0.05). The main glucosinolate breakdown products were as follows: the sinigrin breakdown product, 1-cyano-2,3-epithiopropane (ca. 38 mM); the gluconapin hydrolysis product, 3-butenyl isothiocyanate (ca. 2.2.mM); the glucobrassicin metabolite, ascorbigen (ca. 8 mM); and low concentrations of other indole glucosinolate-derived hydrolysis products such as neoascorbigen and 3,3'-diindolylmethane. A variety of biologically active glucosinolate breakdown products are released by mechanical disruption of raw Brussels sprout tissue, but contrary to previous assumptions, allyl isothiocyanate is not the main compound responsible for the inhibition of cell proliferation.     

Childhood diet in relation to Sámi and Norwegian ethnicity in northern and mid-Norway--the SAMINOR study

OBJECTIVE: The purpose of this work was to identify dietary patterns in the past using cluster analysis of reported diet in childhood, and to assess predictors for dietary patterns in relation to ethnicity in the population in the Sámi core areas in Norway. The Sámis are an indigenous population living in the border areas of Norway, Sweden, Finland and Russia. DESIGN: Population-based, cross-sectional study, using self-administered questionnaires. A food-frequency questionnaire covering selected food items eaten in childhood was used. The questionnaire also provided data on ethnicity. SUBJECTS AND SETTING: This study was based on data collected from 7614 subjects participating in The Population Based Study of Health and Living Conditions in Areas with a Mixed Sámi and Norwegian Population (the SAMINOR study) who grew up in the SAMINOR geographical areas, i.e. areas with mixed Sámi and Norwegian populations in Norway. RESULTS: Four dietary clusters were identified: a reindeer meat cluster; a cluster with high intakes of fish, traditional fish products and mutton, in addition to food sources from the local environment; a Westernised food cluster with high intakes of meat balls and sausages; and a cluster with a high intake of fish, but not any other foods in the questionnaire. The cluster distribution differed by ethnicity, but the effect of ethnicity on diet differed by coastal and inland residence. CONCLUSION: Our study has shown that data gathered through the limited questionnaire could be used to group the study sample into different dietary clusters, which we believe will be useful for further research on relationships between diet in childhood and health in the Sámi core areas in Norway.     

Cross-sectional study on acrylamide hemoglobin adducts in subpopulations from the European Prospective Investigation into Cancer and Nutrition (EPIC) Study

Acrylamide exposure was investigated in subgroups of the EPIC study population (510 subjects from 9 European countries, randomly selected and stratified by age, gender, and smoking status) using hemoglobin adducts of acrylamide (HbAA) and its primary metabolite glycidamide (HbGA). Blood samples were analyzed for HbAA and HbGA by HPLC/MS/MS. Statistical models for HbAA and HbGA were developed including body mass index (BMI), educational level, and physical activity. A large variability in acrylamide exposure and metabolism between individuals and country groups was observed with HbAA and HbGA values ranging between 15-623 and 8-377 pmol/g of Hb, respectively. Both adducts differed significantly by country, sex, and smoking status. HbGA values were significantly lower in high alcohol consumers than in moderate consumers. With increasing BMI, HbGA in nonsmokers and HbAA in smokers decreased significantly. In the assessment of potential health effects related to acrylamide exposure, country of origin, BMI, alcohol consumption, sex, and smoking status should be considered.     

Breeding gains and changes in morphotype of Nordic spring wheat (1901–1993) under contrasting environments

Phenotypic diversity among 75 Nordic spring wheat cultivars was assessed in a glasshouse experiment, in which plots had no fertilizer or received 14-3-23 NPK plus Mg. On average, the fertilizer application delayed flowering by one day, shortened plant height (PH), as well as enhanced the number of fertile tillers (NFT), fresh and dry straw weight (FSW and DSW, respectively), but influenced negatively the dry matter content in the straw (DMCS) and the number of kernels per spike (K/S). The cultivar-by-fertilizer interaction did not affect significantly days to flowering (DF), PH, FSW, DSW, DMCS, thousand kernel weight, and K/S. Only NFT was significantly affected by this interaction. There were significant differences among cultivars for all characteristics, and the breeding gains were significant for improving earliness (as determined by DF), shortening PH, as well as for reducing DSW and DMCS irrespective of the environment. On average, FSW was low in newer cultivars grown in high inputs, while NFT was low in newer cultivars when grown in low inputs. The country of origin affected significantly DF, PH, DMCS, K/S, and 1000-kernel weight. On average, cultivars developed for Finland and Norway were significantly taller, and had higher DMCS. Finnish cultivars also flowered 1 or 2 days earlier and showed higher K/S than cultivars adopted in southern Scandinavia or Norway.     

Fine mapping quantitative trait loci under selective phenotyping strategies based on linkage and linkage disequilibrium criteria

In fine mapping of a large‐scale experimental population where collection of phenotypes are very expensive, difficult to record or time‐demanding, selective phenotyping could be used to phenotype the most informative individuals. Linkage analyses based sampling criteria (LAC) and linkage disequilibrium‐based sampling criteria (LDC) for selecting individuals to phenotype are compared to random phenotyping in a quantitative trait loci (QTL) verification experiment using stochastic simulation. Several strategies based on LAC and LDC for selecting the most informative 30%, 40% or 50% of individuals for phenotyping to extract maximum power and precision in a QTL fine mapping experiment were developed and assessed. Linkage analyses for the mapping was performed for individuals sampled on LAC within families and combined linkage disequilibrium and linkage analyses was performed for individuals sampled across the whole population based on LDC. The results showed that selecting individuals with similar haplotypes to the paternal haplotypes (minimum recombination criterion) using LAC compared to random phenotyping gave at least the same power to detect a QTL but decreased the accuracy of the QTL position. However, in order to estimate unbiased QTL parameters based on LAC in a large half‐sib family, prior information on QTL position was required. The LDC improved the accuracy to estimate the QTL position but not significantly compared to random phenotyping with the same sample size. When applying LDC (all phenotyping levels), the estimated QTL effect were closer to the true value in comparison to LAC. The results showed that the LDC were better than the LAC to select individuals for phenotyping and contributed to detection of the QTL.