Suchergebnisse

Abstract
Hybrid Rugosa is the most winter hardy group of roses in the climatic conditions of the Baltic Sea region. This study aimed at identifying new qualities of Hybrid Rugosa by focusing on determination of content of volatile organic compounds of flower petals and in hydrosols produced from these. Volatiles of seven cultivars were extracted using solid phase microextraction (SPME) with subsequent separation by gas chromatography. Identification was made by comparison with mass spectral libraries and by calculating linear retention indexes and comparing them with literature data. Twenty-five volatile aroma compounds were identified in the petals and hydrosols of six Hybrid Rugosa and species. Among those, phenylethylalcohol, ß-citronellol, geraniol and nerol were predominant. Species Rosa rugosa and variety 'Plena' showed the highest total level of volatiles and contained 26% and 31% ß-citronellol, respectively. Varieties 'Raita' and 'Sniedze' contained up to 57% citronellol. The main volatile compounds were detected in hydrosols in the same proportions, but their concentration was higher than in petals. The varieties 'Raita' and 'Violeta', bred in Latvia, are recommendable for use as a source of hydrosol.

Genome-Wide and Mla Locus-Specific Characterisation of Latvian Barley Varieties
Genetic diversity in locally adapted germplasm forms the basis for crop improvement through breeding. While single loci have been routinely used for studies of genetic diversity, the highthroughput genotyping platforms that have recently become available for large genome crop plants offer an unbiased view on genetic diversity on a genome-wide scale. We assessed genetic diversity in Latvian barley varieties and some progenitors using DArT markers and studied the extent of linkage disequilibrium in Latvian germplasm. Further, genetic diversity at three loci flanking the barley powdery mildew Mla locus conferring race-specific resistance was studied in Latvian barley germplasm. The Mla locus encompasses several closely related resistance gene homologues with a complex evolutionary history, which complicates the design of molecular markers for different Mla genes. We observed significant linkage disequilibrium between the single nucleotide polymorphisms (SNPs) at the three loci, 206i20_T7, ABC15612, and 538P8, flanking the Mla locus. SNP haplotypes were largely in agreement with known phenotypic data and, thus, may be potentially diagnostic for Mla resistance genes in hybrids.

Abstract
Genetic diversity among 13 northern populations of the declining coastal plant Eryngium maritimum L. at the northernmost extent of the species distribution range was studied using retro-transposon-based SSAP molecular markers. Diversity indices varied extensively among populations; some showing extremely low diversity whereas other populations exhibited moderate amounts of genetic variation. Differentiation among populations was highly variable as well. Interestingly, differentiation among northern populations was not influenced strongly by geographic distance. Closely situated populations were often more divergent than more distant populations suggesting other factors may be responsible for genetic structuring of E. maritimum populations. We propose that the following genetic and environmental factors combine together in a complex relationship to mould the present genetic structure of E. maritimum populations in this region: (1) historic biogeographical processes; (2) local environmental conditions at each site; (3) success of sexual reproduction and proportion of clonal propagation; (4) size of the population and influence of genetic drift; (5) level of fragmentation and isolation. Lastly, we suggest that the sustainable existence of Latvian populations is seriously threatened, unless recommended conservation measures are implemented.

Abstract
Potato breeding clones were evaluated for resistance to late blight (agent Phytophthora infestans) using tuber inoculation tests and for presence of the resistance alleles of R1 and R3a genes in polymerase chain reaction tests. Among clones tested those expressing high, moderate and low resistance were identified. The data were analysed for the impact of R1 and R3a genes on tuber resistance to late blight in tested plant material. In previous evaluations performed on smaller amount of clones the tuber resistance levels significantly depended on presence/absence of the resistance allele of R3a gene and did not depend on presence of R1 gene allele. In the current study the statistical analyses did not prove the significant difference in resistance levels depending on presence of the resistance alleles, neither of R1 gene, nor of R3a gene. Tuber resistant clones bearing R3a gene resistance alleles still noticeably prevailed over the clones bearing the alleles of R1 gene as well as over the clones bearing the no resistance alleles of both genes. In several cases the resistance of clones with detected resistance allele of R1 gene was higher compared to those derived from the same crosses and showing amplification of the allele of R3a gene or those with no resistance alleles. Clones accumulating the resistance alleles of both (R1 and R3a) genes expressed high tuber resistance accompanied by necrotic reaction.

Variation of spring barley agronomic traits significant for adaption to climate change in latvian breeding programmes
Breeding programmes have been recently challenged by climate change. Spring barley (Hordeum vulgare L.) yield, phenological traits (days to heading, length of filling period and days to maturity) and resistance to powdery mildew and net blotch, which are influenced by the rising temperature and precipitation, along with threshability in hulless, were evaluated and their genetic and environmental variability were determined. One hundred and ninety spring barley genotypes were studied, including 129 hulless genotypes and 61 hulled genotypes. The genotypes were grown in the State Stende Cereal Breeding Institute and State Priekuļi Plant Breeding Institute for three seasons during 2007-2009. Broad-sense heritability estimated on the basis of genotypical and phenotypical variances for all traits of hulled barley varied from 31 to 98, and 42 to 98% for hulless barley. For both types of barley the highest heritability was observed for days to heading, filling period and days to maturity. Despite the relatively high estimated heritability for all traits, nevertheless, location, year and interaction of genotype and environment were also been significant for all traits.

Genetically modified organisms (GMO), mainly crop plants, are increasingly grown worldwide leading to large trade volumes of living seeds and other plant material both for cultivation and for food and animal feed. Even though all the traded GMOs have been assessed for their safety with regards to human and animal health and the environment, there still are some concerns regarding the potential uncontrolled release in the environment of authorized or unauthorized GM plants. In this review, we identify the possible entrance routes of GM seeds and other propagating plant material in the EU which could be linked to unauthorized release of GMOs in the environment. In addition, we discuss the situation with GM plant cultivation in some non-EU countries in terms of potential risks for GM seed imports. The available body of information suggests that GM seeds and plant propagating material can enter the EU due to problems with labeling/traceability of GM seed lots, contamination of conventional seed lots and accidental release into the environment of grains imported for food and animal feed. Even though cases of uncontrolled release of authorized GMOs, as well as, release of unauthorized GMOs have been reported, they can be generally attributed to adventitious and technically unavoidable presence with little environmental impact. In conclusion, the probability of GM seeds and plant propagating material illegally entering the cultivation in EU is unlikely. However, specific monitoring programs need to be established and maintained to facilitate the compliance of European farmers with the current GMO legislation.

Abstract
The oomycete Phytophthora infestans Mont. (de Bary), which causes potato late blight, and Potato Virus Y (PVY) are economically important potato pathogens. More virulent P. infestans strains have evolved and are able to overcome resistance genes introgressed earlier to cultivated potato from wild Solanum species, especially from S. demissim Lindl. Potato cultivars resistant to the previously common type of PVYN may be susceptible to the more virulent isolates of PVY. In previous research, S. guerreroense Corr. (grr) and S. neoantipoviczii Buk. (nan) accessions were rated as resistant to P. infestans and to two (grr) and three (nan) strains of PVY. These parental accessions and their respective hybrid offspring were screened using polymerase chain reaction (PCR) tests to detect alleles conferring resistance to P. infestans (R1 and R3) and to PVY (Rysto). Screenings were made in detached leaflet tests (P. infestans), and with the aid of ELISA tests (PVY). The resistance of two hybrids derived from grr was rated as high, mostly due to a hypersensitivity reaction. The allele R3 was detected in only one grr plant among 20 plant populations for each grr and nan accession. R1 and R3 alleles were more frequently detected in one hybrid of grr (grr × B.d.R5.). The resistance allele Rysto was found in nan and provided host plant resistance to three strains of PVY, including PVYNTN. Hybrids derived from this accession were characterised by a high frequency of plants bearing the resistant allele Rysto. In the parental clone tbr × phu, as well as in grr and its hybrids, only the susceptible allele at Rysto locus was detected.

Significant attention has been drawn to the adventitious and technically unavoidable presence of genetically modified (GM) organisms in the food and feed imported into the European Union (EU), while the potential presence of GM seeds in material for cultivation is less studied. Here we report a study from an EU member state, Latvia, during years 2017–2018 regarding monitoring for the presence of GM seeds in certified seed and animal feed material. Eighty-two and 28 samples of seeds intended for cultivation were analyzed in 2017 and 2018, respectively. One soybean sample contained MON40-3-2 soybean seeds (0.09 ± 0.01%) and one maize sample contained MON810 maize seeds (0.08 ± 0.01%). In addition, 102 samples of feed imported from outside of the EU or produced locally were also analyzed for the presence of genetically modified organisms (GMOs) and viability of grains. One oilseed rape cake sample contained GT73 (1.04 ± 0.01%) and one soybean cake sample contained MON40-3-2 (<0.045%). One sample of declared MON40-3-2 GM soybean cake was confirmed to be positive, with MON40-3-2 content of 94.78 ± 10.01%. One soybean sample submitted by feed producer and originating from Argentina contained 54.9 ± 1.1% of MON40-3-2 and one rapeseed sample originating from Ukraine contained 5.30 ± 3.95% of GT73. Although only two seed samples contained low levels of GMOs authorized in the EU for food and feed uses, this study reinforced the need to maintain regular monitoring programs that assist farmers in their efforts to comply with the current EU GMO legislation.

The European Food Safety Authority (EFSA) carried out a consultation to collect input from the scientific community and all interested parties for the risk assessment of the low level (LL) presence of genetically modified plant material in imported food and feed under Regulation (EC) No 1829/2003. A two-step approach was followed. The draft LL Scientific Opinion was prepared by the ad hoc Working Group of the EFSA Panel on Genetically Modified Organisms (GMO Panel) and endorsed by the Panel for a dedicated consultation with European Member States at its plenary meeting on 21 September 2016. EFSA received approximately 100 comments on the draft LL Scientific Opinion from 11 Member States. Based on the outcome of the dedicated consultation, a second draft LL Scientific Opinion was prepared and endorsed by the Panel for a dedicated consultation with European Member States at its plenary meeting on 5 April 2017. EFSA received approximately 60 comments on the draft LL Scientific Opinion from 7 interested parties. The current report summarises the outcome of the two-step consultation, and includes a brief description of the comments received and how the comments were addressed. Comments related to policy or risk management aspects were considered out of the remit of the GMO Panel and outside the scope of these consultations; therefore these are not addressed in this document. The GMO Panel prepared an updated version of the LL Scientific Opinion taking into account the comments under its remit received. EFSA and its GMO Panel wish to thank European Member States, all stakeholders and the general public for their contributions. The LL Scientific

The European Food Safety Authority (EFSA) carried out a consultation to collect input from the scientific community and all interested parties for the risk assessment of the low level (LL) presence of genetically modified plant material in imported food and feed under Regulation (EC) No 1829/2003. A two-step approach was followed. The draft LL Scientific Opinion was prepared by the ad hoc Working Group of the EFSA Panel on Genetically Modified Organisms (GMO Panel) and endorsed by the Panel for a dedicated consultation with European Member States at its plenary meeting on 21 September 2016. EFSA received approximately 100 comments on the draft LL Scientific Opinion from 11 Member States. Based on the outcome of the dedicated consultation, a second draft LL Scientific Opinion was prepared and endorsed by the Panel for a dedicated consultation with European Member States at its plenary meeting on 5 April 2017. EFSA received approximately 60 comments on the draft LL Scientific Opinion from 7 interested parties. The current report summarises the outcome of the two-step consultation, and includes a brief description of the comments received and how the comments were addressed. Comments related to policy or risk management aspects were considered out of the remit of the GMO Panel and outside the scope of these consultations; therefore these are not addressed in this document. The GMO Panel prepared an updated version of the LL Scientific Opinion taking into account the comments under its remit received. EFSA and its GMO Panel wish to thank European Member States, all stakeholders and the general public for their contributions. The LL Scientific

The European Food Safety Authority (EFSA) carried out a consultation to collect input from the scientific community and all interested parties for the risk assessment of the low level (LL) presence of genetically modified plant material in imported food and feed under Regulation (EC) No 1829/2003. A two-step approach was followed. The draft LL Scientific Opinion was prepared by the ad hoc Working Group of the EFSA Panel on Genetically Modified Organisms (GMO Panel) and endorsed by the Panel for a dedicated consultation with European Member States at its plenary meeting on 21 September 2016. EFSA received approximately 100 comments on the draft LL Scientific Opinion from 11 Member States. Based on the outcome of the dedicated consultation, a second draft LL Scientific Opinion was prepared and endorsed by the Panel for a dedicated consultation with European Member States at its plenary meeting on 5 April 2017. EFSA received approximately 60 comments on the draft LL Scientific Opinion from 7 interested parties. The current report summarises the outcome of the two-step consultation, and includes a brief description of the comments received and how the comments were addressed. Comments related to policy or risk management aspects were considered out of the remit of the GMO Panel and outside the scope of these consultations; therefore these are not addressed in this document. The GMO Panel prepared an updated version of the LL Scientific Opinion taking into account the comments under its remit received. EFSA and its GMO Panel wish to thank European Member States, all stakeholders and the general public for their contributions. The LL Scientific

The European Food Safety Authority (EFSA) carried out a consultation to collect input from the scientific community and all interested parties for the risk assessment of the low level (LL) presence of genetically modified plant material in imported food and feed under Regulation (EC) No 1829/2003. A two-step approach was followed. The draft LL Scientific Opinion was prepared by the ad hoc Working Group of the EFSA Panel on Genetically Modified Organisms (GMO Panel) and endorsed by the Panel for a dedicated consultation with European Member States at its plenary meeting on 21 September 2016. EFSA received approximately 100 comments on the draft LL Scientific Opinion from 11 Member States. Based on the outcome of the dedicated consultation, a second draft LL Scientific Opinion was prepared and endorsed by the Panel for a dedicated consultation with European Member States at its plenary meeting on 5 April 2017. EFSA received approximately 60 comments on the draft LL Scientific Opinion from 7 interested parties. The current report summarises the outcome of the two-step consultation, and includes a brief description of the comments received and how the comments were addressed. Comments related to policy or risk management aspects were considered out of the remit of the GMO Panel and outside the scope of these consultations; therefore these are not addressed in this document. The GMO Panel prepared an updated version of the LL Scientific Opinion taking into account the comments under its remit received. EFSA and its GMO Panel wish to thank European Member States, all stakeholders and the general public for their contributions. The LL Scientific

The European Food Safety Authority (EFSA) carried out a consultation to collect input from the scientific community and all interested parties for the risk assessment of the low level (LL) presence of genetically modified plant material in imported food and feed under Regulation (EC) No 1829/2003. A two-step approach was followed. The draft LL Scientific Opinion was prepared by the ad hoc Working Group of the EFSA Panel on Genetically Modified Organisms (GMO Panel) and endorsed by the Panel for a dedicated consultation with European Member States at its plenary meeting on 21 September 2016. EFSA received approximately 100 comments on the draft LL Scientific Opinion from 11 Member States. Based on the outcome of the dedicated consultation, a second draft LL Scientific Opinion was prepared and endorsed by the Panel for a dedicated consultation with European Member States at its plenary meeting on 5 April 2017. EFSA received approximately 60 comments on the draft LL Scientific Opinion from 7 interested parties. The current report summarises the outcome of the two-step consultation, and includes a brief description of the comments received and how the comments were addressed. Comments related to policy or risk management aspects were considered out of the remit of the GMO Panel and outside the scope of these consultations; therefore these are not addressed in this document. The GMO Panel prepared an updated version of the LL Scientific Opinion taking into account the comments under its remit received. EFSA and its GMO Panel wish to thank European Member States, all stakeholders and the general public for their contributions. The LL Scientific