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Jokioinen, Finland

Jalli M.,Mtt Agrifood Research Finland
Annals of Applied Biology

Knowledge of the virulence of a pathogen population and recognition of the risks of changes in the virulence spectrum are essential in breeding crops for disease resistance. Sexual recombination in a pathogen increases the level of genotypic diversity and can influence the virulence spectrum. This study aimed to determine how sexual recombination can change virulence of the barley pathogen Pyrenophora teres and whether the barley cultivation system, no-tillage or normal tillage, influences P. teres virulence. The inheritance of avirulence/virulence in P. teres following sexual reproduction was studied in three artificially created pathogen populations. The first was a product of crossing two net forms of the pathogen, and the second and the third were products of crossing net and spot forms. None of the progeny generated resembled the parents exactly. The average similarity of the progeny isolates of the net by net cross with the parental type, based on avirulence/virulence tests, was 92%. That for net and spot form progenies was 58% in comparison with the net form parents and 73% with the spot form parents. The virulence reactions of the progeny isolates did not correlate with morphological traits of the isolates: growth rate on agar, spore production, spore width, spore length and numbers of septa per conidium. To study the effect of the barley cultivation method on P. teres virulence, 313 single-spore cultures were obtained from barley fields. Two hundred and seventy-six of the isolates represented the spot form and 37 represented the net form of P. teres. No association was established between the tillage method and virulence for either the net form or the spot form isolates. © 2010 The Author. Annals of Applied Biology © 2010 Association of Applied Biologists. Source

This study was conducted to examine the performance of growing dairy bulls offered diets based on whole-crop barley silage with or without protein supplementation when compared to a grass silage-based diet. A feeding experiment comprised 36 bulls which were fed a total mixed ration ad libitum. The four dietary treatments were: 1) grass silage (600 g kg-1 dry matter) and rolled barley (400), 2) whole-crop barley silage (600) and rolled barley (400), 3) whole-crop barley silage (600), rolled barley (310) and rapeseed meal-based protein supplementation (90), and 4) whole-crop barley silage (600), rolled barley (330) and rapeseed meal + urea -based protein supplementation (70). Replacing grass silage with whole-crop barley decreased the carcass gain and carcass weight of the bulls due to lower energy intake. Protein supplementation either as rapeseed meal or rapeseed meal + urea of whole-crop barley silage based diets had no effects on animal performance. Source

Luste S.,University of Eastern Finland | Luostarinen S.,Mtt Agrifood Research Finland
Bioresource Technology

Anaerobic co-digestion of a mixture of animal by-products (ABP) from meat-processing industry and of sewage sludge was studied at 35 °C for co-digesting such by-products in digesters at wastewater treatment plants. The three reactors were fed with ABP mixture and sewage sludge (1) in a ratio of 1:7 (v/v), (2) in the same ratio but with hygienization (70 °C, 60 min) and (3) in a ratio of 1:3 (v/v). Hydraulic retention time (HRT) was decreased from 25 to 20 days and finally to 14 days, while organic loading rates (OLR) ranged from 1.8 to 4.0 kg VS/m3 day. The highest specific methane yields were achieved with 20-days-HRT (1) 400 ± 30, (2) 430 ± 40, (3) 410 ± 30 m3 CH4/t VS. Hygienization improved methane production to a level above the highest OLR applied (feed ratio 1:3 (3)), while the quality of the digestate remained similar to the other reactors. © 2009 Elsevier Ltd. All rights reserved. Source

This study elaborates the dynamic nutrient balance model and applies it to analyze nitrogen use and nitrogen efficiency in agriculture. We use publicly available agricultural production data to estimate the net inflows, stocks and outflows of nitrogen for 14 European countries in years 1961-2009. The dynamic model allows us to analyze the trends in the nitrogen stocks and flows over time, and break down the total outflow of nitrogen into flows to water, air and soil. We argue that the nitrogen outflow, modeled as the decay of nitrogen stock, provides a more reliable and robust agri-environmental indicator than the conventional nutrient balance. Mathematically, the nutrient balance is an interval scale measure, whereas the nitrogen stock and the outflow from stock are ratio scale measures. Nitrogen efficiencies, calculated based on the nitrogen stocks, provide useful and insightful information beyond the conventional eco-efficiency measures defined from the nitrogen balances. The results of this paper can be used as input data for more comprehensive eco-efficiency or productivity analysis and for the evaluation and design of agri-environmental policies in Europe. © 2014 Elsevier B.V. Source

Uimari P.,Mtt Agrifood Research Finland
Genetics, selection, evolution : GSE

Good genetic progress for pig reproduction traits has been achieved using a quantitative genetics-based multi-trait BLUP evaluation system. At present, whole-genome single nucleotide polymorphisms (SNP) panels provide a new tool for pig selection. The purpose of this study was to identify SNP associated with reproduction traits in the Finnish Landrace pig breed using the Illumina PorcineSNP60 BeadChip. Association of each SNP with different traits was tested with a weighted linear model, using SNP genotype as a covariate and animal as a random variable. Deregressed estimated breeding values of the progeny tested boars were used as the dependent variable and weights were based on their reliabilities. Statistical significance of the associations was based on Bonferroni-corrected P-values. Deregressed estimated breeding values were available for 328 genotyped boars. Of the 62,163 SNP in the chip, 57,868 SNP had a call rate > 0.9 and 7,632 SNP were monomorphic. Statistically significant results (P-value < 2.0E-06) were obtained for total number of piglets born in first and later parities and piglet mortality between birth and weaning in later parity, and suggestive associations (P-value < 4.0E-06) for piglet mortality between birth and weaning in first parity, number of stillborn piglets in later parity, first farrowing interval and second farrowing interval. Two of the statistically significant regions for total number of piglets born in first and later parities are located on chromosome 9 around 95 and 79 Mb. The estimated SNP effect in these regions was approximately one piglet between the two homozygote classes. By combining the two most significant SNP in these regions, favourable double homozygote animals are expected to have 1.3 piglets (P-value = 1.69E-08) more than unfavourable double homozygote animals. A region on chromosome 9 (66 Mb) was statistically significant for piglet mortality between birth and weaning in later parity (0.44 piglets between homozygotes, P-value = 6.94E-08). Three separate regions on chromosome 9 gave significant results for litter size and pig mortality. The frequencies of favourable alleles of the significant SNP are moderate in the Finnish Landrace population and these SNP are thus valuable candidates for possible marker-assisted selection. Source

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