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524 Research products, page 1 of 53

  • Rural Digital Europe
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  • Rural Digital Europe

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  • Authors: 
    Leslie R. Adrian; Donato Repole; Leonids Ribickis;
    Publisher: IEEE

    The purpose of this paper is to address current issues in industrial robotics applications and to address also the current trends occurring in the industry regarding smaller mobile units in factory and external manufacturing processes relating to the battery powering of robotics devices. Specifically, we shall concentrate the efforts herein on “Mobile Industrial Robotics”. The paper touches briefly on problems associated with both definitions of industrial robots and problems associated with power supply sources of mobile industrial robotics and provides an outline of future work with appropriate solution for smaller mobile industrial mobile units operating in the variable input range of 24V to 48v and outputs in the range of 3.3V to 12V @ 20A in three stages. The project required a fast, turn-key solution which did not allow for a “design from scratch” solution and so detailed herein is suitable design produced in other sectors and relating the details, design process, modelling and examination of a successful and efficient high current DC to DC switch mode power supply. Parameters have been adjusted to our own preferences in the design considerations regarding “Industrial Service Hybrids” [1] (ISH)1. Other design issues are under assessment and shall be included as the project moves forward.

  • Open Access
    Authors: 
    Agita Gancone; Jelena Pubule; Marika Rosa; Dagnija Blumberga;
    Publisher: Elsevier BV

    Abstract Agriculture is the second most significant source of greenhouse gas (GHG) emissions, with approximately 24 % of Latvia’s total GHG emissions in 2014. Emissions from agricultural soils contributed major share of the total emissions – 59.6 %, enteric fermentation emissions was second largest source – 32 %. The share of manure management emissions was evaluated as 7.5 % of total emissions in the sector, remaining 0.9 % of emissions refer to liming and urea application. GHG emissions increased in 2014 by 3.3 % comparing to 2013 due to increase of cattle, sheep and fur animal numbers. Statistics also showed increase of synthetic N fertilizer consumption approximately by 4.6 %, sown area by 0.3 % and lime application to soils 42.9 % [1]. Bearing in mind significant share of agricultural emissions in total GHG emissions in Latvia and the growing emission trend the additional attention is necessary for evaluation of impacts of agriculture on the environment. The purpose of this study is to explore indicators for assessing eco-efficiency in the Latvian agriculture sector. First the paper describes methods which can be used for measuring eco-efficiency, second availability of activity data and third, presents calculations of selected indicators for eco-efficiencies.

  • Open Access English
    Authors: 
    Kristine Valujeva; Kristine Valujeva; Kristine Valujeva; Aleksejs Nipers; Ainars Lupikis; Rogier P. O. Schulte;
    Country: Netherlands
    Project: EC | LANDMARK (635201)

    The increased demand for bio based products worldwide provides an opportunity for Eastern European countries to increase their production in agriculture and forestry. At the same time, such economic development must be congruent with the European Union’s long-term climate and biodiversity objectives. As a country that is rich in bioresources, the Latvian case study is highly relevant to many other countries—especially those in Central and Eastern Europe—and faces a choice of transition pathways to meet both economic and environmental objectives. In order to assess the trade-offs between investments in the bioeconomy and the achievement of climate and biodiversity objectives, we used the Functional Land Management (FLM) framework for the quantification of the supply and demand for the primary productivity, carbon regulation and biodiversity functions. We related the supply of these three soil functions to combinations of land use and soil characteristics. The demand for the same functions were derived from European, national and regional policy objectives. Our results showed different spatial scales at which variation in demand and supply is manifested. High demand for biodiversity was associated with areas dominated by agricultural land at the local scale, while regional differences of unemployment rates and the target for GDP increases framed the demand for primary productivity. National demand for carbon regulation focused on areas dominated by forests on organic soils. We subsequently identified mismatches between the supply and demand for soil functions, and we selected spatial locations for specific land use changes and improvements in management practices to promote sustainable development of the bio-economy. Our results offer guidance to policy makers that will help them to form a national policy that will underpin management practices that are effective and tailored toward local climate conditions and national implementation pathways.

  • Publication . Part of book or chapter of book . 2018
    Closed Access
    Authors: 
    Maris Klavins; Vaira Obuka;
    Publisher: Springer International Publishing

    A major driving force to promote the idea of sustainable bioeconomy could be local experiences, skills and knowledge in respect to the use of local and natural materials (at first, biomaterials). Sustainable bioeconomy is a concept under development, and as such it requires argumentation and demonstration of efficiency. The aim of this chapter is to study the local knowledge of the Baltic region in terms of the applicability of local biomaterials in production. In the context of bioeconomy, there is an evident need to identify the possibilities for the use of natural and local materials as well as the knowledge to manage these resources. Natural materials of the Baltic region, such as hemp, straw, timber, grain processing products (husk), reeds, moss and flax, will be studied in the historical context and in the use for innovations in modern bioeconomy. In addition, such resources as clay, organic lake sediments (sapropel), peat, sludge, ash, coal and biochar will be evaluated as potential source materials for the manufacture of innovative products. Regarding the use of natural resources, different sectors will be analysed, for example, agriculture and construction. The obtained results will give an insight into the knowledge and traditions of the Baltic region concerning the use of natural materials as a key for sustainability.

  • Open Access
    Authors: 
    Sandis Dejus; Alīna Neščerecka; G. Kurcalts; Tālis Juhna;
    Publisher: IWA Publishing

    Abstract Concerns about drinking water (DW) quality contamination during water distribution raise a need for real-time monitoring and rapid contamination detection. Early warning systems (EWS) are a potential solution. The EWS consist of multiple conventional sensors that provide the real-time measurements and algorithms that allow the recognizing of contamination events from normal operating conditions. In most cases, these algorithms have been established with artificial data, while data from real and biological contamination events are limited. The goal of the study was the event detection performance of the Mahalanobis distance method in combination with on-line DW quality monitoring sensors and manual measurements of grab samples for potential DW biological contamination scenarios. In this study three contamination scenarios were simulated in a pilot-scale DW distribution system: untreated river water, groundwater and wastewater intrusion, which represent realistic contamination scenarios and imply biological contamination. Temperature, electrical conductivity (EC), total organic carbon (TOC), chlorine ion (Cl-), oxidation–reduction potential (ORP), pH sensors and turbidity measurements were used as on-line sensors and for manual measurements. Novel adenosine-triphosphate and flow cytometric measurements were used for biological water quality evaluation. The results showed contamination detection probability from 56% to 89%, where the best performance was obtained with manual measurements. The probability of false alarm was 5–6% both for on-line and manual measurements. The Mahalanobis distance method with DW quality sensors has a good potential to be applied in EWS. However, the sustainability of the on-line measurement system and/or the detection algorithm should be improved.

  • Open Access
    Authors: 
    Aleksejs Nipers; Irina Pilvere; Agnese Krievina; Valda Bratka;
    Publisher: Latvia University of Life Sciences and Technologies
  • Open Access English
    Authors: 
    Inga Stafecka; Veneranda Stramkale; Dace Grauda;
    Publisher: Rezekne Academy of Technologies

    Flax is the multiple purpose crop cultivated in temperate region. Seeds of oil flax recently became important constituent for many industrial applications, such as pharmacy, medicine, food production <em>etc.</em> and have high prospective for use in Latvia. Understanding the underlying processes that limit seed yield in flax is major with respect to enhancing the breeding of flax for yield improvements. The aim of study was evaluated 29 flax varieties and lines (including 20 Latvian origins) plasticity of seed yield production in changeable environmental conditions. The experiment was carried out in the Agricultural Scientific Centre of Latgale on field trials over the period 2010-2013. The aim of this study was evaluated plasticity in changeable environmental conditions for 29 flax varieties and lines (including 20 Latvian origins). According to 4 years results was to establish the nature of relation between seed yield and hydrothermal coefficient (HTC), and seed yield and another yield components of flax. Apart from the changing conditions highest seed yield were produced from a varieties ‘Lirina’ (2.54 h <sup>-1</sup>t), high seed oil content from variety ‘Amon’ (53.03%). Positive and significant relationships were found between seed yield and HTC ‘T30-28-6-94’(r=+0.98*), ‘German Serenade’ (r=+0.95*) and ‘Scorpion’ (r =+0.95*).

  • Publication . Article . Conference object . 2015
    Open Access English
    Authors: 
    Ļubova Komlajeva; Aleksandrs Adamovics;
    Publisher: Rezeknes Augstskola

    Flax is cultivated on small areas in Latvia. Flax gives dual-purpose production – fibre and seeds. Latvian flax has a high fibre and seed quality. The quantity of flax fibre and seed yield depends on many factors. Several qualitative and quantitative traits, such as technical stem length, resistance to lodging, vegetation period, yield of straw and seeds, fibre and oil content and quality were evaluated. For the further development of Latvian economy flax varieties and hybrids of Latvian origin are an important goal. Fibre flax varieties 'Blue di Riga', 'Priekuļu 665', 'Ošupes 30' and breeding lines 'S-64-17-93' and 'L11-11/11-94' are valuable material containing a qualitative and quantitative indicators of variety. 92 Latvian accessions of flax hybrids have been evaluated, and 12 accessions with the best seed and straw yield have been selected for further DNA analysis. This will simplify and accelerate the selection of new valuable hybrids that will provide particular advantages in agriculture. The genetic analysis of DNA determines the kinship and diversity of flax varieties and breeding lines which can be used further in flax breeding.

  • Publication . Article . Other literature type . 2015
    Open Access English
    Authors: 
    Laura M. E. Sutcliffe; Péter Batáry; Urs G. Kormann; András Báldi; Lynn V. Dicks; Irina Herzon; David Kleijn; Piotr Tryjanowski; Iva Apostolova; Raphaël Arlettaz; +33 more
    Countries: Germany, United Kingdom, Finland, France, Germany, Spain, Switzerland, Croatia, Netherlands, Italy
    Project: EC | LIBERATION (311781), UKRI | To exchange knowledge bet... (NE/J500665/1)

    A large proportion of European biodiversity today depends on habitat provided by low‐intensity farming practices, yet this resource is declining as European agriculture intensifies. Within the European Union, particularly the central and eastern new member states have retained relatively large areas of species‐rich farmland, but despite increased investment in nature conservation here in recent years, farmland biodiversity trends appear to be worsening. Although the high biodiversity value of Central and Eastern European farmland has long been reported, the amount of research in the international literature focused on farmland biodiversity in this region remains comparatively tiny, and measures within the EU Common Agricultural Policy are relatively poorly adapted to support it. In this opinion study, we argue that, 10 years after the accession of the first eastern EU new member states, the continued under‐representation of the low‐intensity farmland in Central and Eastern Europe in the international literature and EU policy is impeding the development of sound, evidence‐based conservation interventions. The biodiversity benefits for Europe of existing low‐intensity farmland, particularly in the central and eastern states, should be harnessed before they are lost. Instead of waiting for species‐rich farmland to further decline, targeted research and monitoring to create locally appropriate conservation strategies for these habitats is needed now. Volkswagen Foundation

  • Open Access
    Authors: 
    Neda Zuļģe; Anna Kāle; Alina Gospodaryk; Kristīne Vēvere; Inga Moročko-Bičevska;
    Publisher: Walter de Gruyter GmbH

    Abstract Apples and pears are among the most important commercial fruit species grown in Latvia. Because of suitability to local climatic conditions, mainly domestic cultivars and cultivars originating in neighbouring countries are grown. The planting material of pome fruits produced and used for establishment of new orchards in Latvia corresponds to the Conformitas Agraria Communitatis standard due to the unavailability of nuclear stock. To establish virus-tested, experimental nuclear stock for apple and pear, one to two years old candidate plants were exposed to thermotherapy at +38 °C for 40 to 70 days. The mother trees and candidate plants before treatment were tested for the presence of the four most widespread pome fruit viruses by RT-PCR. The shoot tips of the heat-treated plants were grafted onto seedling rootstocks and were re-tested for the four viruses by RT-PCR during the next three to five vegetation seasons. Several plants of apple cultivars ‘Dace’, ‘Zarja Alatau’, ‘Rubin’, and ‘Ausma’ remained infected either with Apple chlorotic leaf spot virus, Apple stem growing virus or Apple stem pitting virus after the thermotherapy. Tests on woody indicators were carried out to determine possible presence of graft-transmittable organisms according to EPPO guidelines for the establishment of nuclear stock material for pome fruits.

Advanced search in Research products
Research products
arrow_drop_down
Searching FieldsTerms
Any field
arrow_drop_down
includes
arrow_drop_down
Include:
The following results are related to Rural Digital Europe. Are you interested to view more results? Visit OpenAIRE - Explore.
524 Research products, page 1 of 53
  • Authors: 
    Leslie R. Adrian; Donato Repole; Leonids Ribickis;
    Publisher: IEEE

    The purpose of this paper is to address current issues in industrial robotics applications and to address also the current trends occurring in the industry regarding smaller mobile units in factory and external manufacturing processes relating to the battery powering of robotics devices. Specifically, we shall concentrate the efforts herein on “Mobile Industrial Robotics”. The paper touches briefly on problems associated with both definitions of industrial robots and problems associated with power supply sources of mobile industrial robotics and provides an outline of future work with appropriate solution for smaller mobile industrial mobile units operating in the variable input range of 24V to 48v and outputs in the range of 3.3V to 12V @ 20A in three stages. The project required a fast, turn-key solution which did not allow for a “design from scratch” solution and so detailed herein is suitable design produced in other sectors and relating the details, design process, modelling and examination of a successful and efficient high current DC to DC switch mode power supply. Parameters have been adjusted to our own preferences in the design considerations regarding “Industrial Service Hybrids” [1] (ISH)1. Other design issues are under assessment and shall be included as the project moves forward.

  • Open Access
    Authors: 
    Agita Gancone; Jelena Pubule; Marika Rosa; Dagnija Blumberga;
    Publisher: Elsevier BV

    Abstract Agriculture is the second most significant source of greenhouse gas (GHG) emissions, with approximately 24 % of Latvia’s total GHG emissions in 2014. Emissions from agricultural soils contributed major share of the total emissions – 59.6 %, enteric fermentation emissions was second largest source – 32 %. The share of manure management emissions was evaluated as 7.5 % of total emissions in the sector, remaining 0.9 % of emissions refer to liming and urea application. GHG emissions increased in 2014 by 3.3 % comparing to 2013 due to increase of cattle, sheep and fur animal numbers. Statistics also showed increase of synthetic N fertilizer consumption approximately by 4.6 %, sown area by 0.3 % and lime application to soils 42.9 % [1]. Bearing in mind significant share of agricultural emissions in total GHG emissions in Latvia and the growing emission trend the additional attention is necessary for evaluation of impacts of agriculture on the environment. The purpose of this study is to explore indicators for assessing eco-efficiency in the Latvian agriculture sector. First the paper describes methods which can be used for measuring eco-efficiency, second availability of activity data and third, presents calculations of selected indicators for eco-efficiencies.

  • Open Access English
    Authors: 
    Kristine Valujeva; Kristine Valujeva; Kristine Valujeva; Aleksejs Nipers; Ainars Lupikis; Rogier P. O. Schulte;
    Country: Netherlands
    Project: EC | LANDMARK (635201)

    The increased demand for bio based products worldwide provides an opportunity for Eastern European countries to increase their production in agriculture and forestry. At the same time, such economic development must be congruent with the European Union’s long-term climate and biodiversity objectives. As a country that is rich in bioresources, the Latvian case study is highly relevant to many other countries—especially those in Central and Eastern Europe—and faces a choice of transition pathways to meet both economic and environmental objectives. In order to assess the trade-offs between investments in the bioeconomy and the achievement of climate and biodiversity objectives, we used the Functional Land Management (FLM) framework for the quantification of the supply and demand for the primary productivity, carbon regulation and biodiversity functions. We related the supply of these three soil functions to combinations of land use and soil characteristics. The demand for the same functions were derived from European, national and regional policy objectives. Our results showed different spatial scales at which variation in demand and supply is manifested. High demand for biodiversity was associated with areas dominated by agricultural land at the local scale, while regional differences of unemployment rates and the target for GDP increases framed the demand for primary productivity. National demand for carbon regulation focused on areas dominated by forests on organic soils. We subsequently identified mismatches between the supply and demand for soil functions, and we selected spatial locations for specific land use changes and improvements in management practices to promote sustainable development of the bio-economy. Our results offer guidance to policy makers that will help them to form a national policy that will underpin management practices that are effective and tailored toward local climate conditions and national implementation pathways.

  • Publication . Part of book or chapter of book . 2018
    Closed Access
    Authors: 
    Maris Klavins; Vaira Obuka;
    Publisher: Springer International Publishing

    A major driving force to promote the idea of sustainable bioeconomy could be local experiences, skills and knowledge in respect to the use of local and natural materials (at first, biomaterials). Sustainable bioeconomy is a concept under development, and as such it requires argumentation and demonstration of efficiency. The aim of this chapter is to study the local knowledge of the Baltic region in terms of the applicability of local biomaterials in production. In the context of bioeconomy, there is an evident need to identify the possibilities for the use of natural and local materials as well as the knowledge to manage these resources. Natural materials of the Baltic region, such as hemp, straw, timber, grain processing products (husk), reeds, moss and flax, will be studied in the historical context and in the use for innovations in modern bioeconomy. In addition, such resources as clay, organic lake sediments (sapropel), peat, sludge, ash, coal and biochar will be evaluated as potential source materials for the manufacture of innovative products. Regarding the use of natural resources, different sectors will be analysed, for example, agriculture and construction. The obtained results will give an insight into the knowledge and traditions of the Baltic region concerning the use of natural materials as a key for sustainability.

  • Open Access
    Authors: 
    Sandis Dejus; Alīna Neščerecka; G. Kurcalts; Tālis Juhna;
    Publisher: IWA Publishing

    Abstract Concerns about drinking water (DW) quality contamination during water distribution raise a need for real-time monitoring and rapid contamination detection. Early warning systems (EWS) are a potential solution. The EWS consist of multiple conventional sensors that provide the real-time measurements and algorithms that allow the recognizing of contamination events from normal operating conditions. In most cases, these algorithms have been established with artificial data, while data from real and biological contamination events are limited. The goal of the study was the event detection performance of the Mahalanobis distance method in combination with on-line DW quality monitoring sensors and manual measurements of grab samples for potential DW biological contamination scenarios. In this study three contamination scenarios were simulated in a pilot-scale DW distribution system: untreated river water, groundwater and wastewater intrusion, which represent realistic contamination scenarios and imply biological contamination. Temperature, electrical conductivity (EC), total organic carbon (TOC), chlorine ion (Cl-), oxidation–reduction potential (ORP), pH sensors and turbidity measurements were used as on-line sensors and for manual measurements. Novel adenosine-triphosphate and flow cytometric measurements were used for biological water quality evaluation. The results showed contamination detection probability from 56% to 89%, where the best performance was obtained with manual measurements. The probability of false alarm was 5–6% both for on-line and manual measurements. The Mahalanobis distance method with DW quality sensors has a good potential to be applied in EWS. However, the sustainability of the on-line measurement system and/or the detection algorithm should be improved.

  • Open Access
    Authors: 
    Aleksejs Nipers; Irina Pilvere; Agnese Krievina; Valda Bratka;
    Publisher: Latvia University of Life Sciences and Technologies
  • Open Access English
    Authors: 
    Inga Stafecka; Veneranda Stramkale; Dace Grauda;
    Publisher: Rezekne Academy of Technologies

    Flax is the multiple purpose crop cultivated in temperate region. Seeds of oil flax recently became important constituent for many industrial applications, such as pharmacy, medicine, food production <em>etc.</em> and have high prospective for use in Latvia. Understanding the underlying processes that limit seed yield in flax is major with respect to enhancing the breeding of flax for yield improvements. The aim of study was evaluated 29 flax varieties and lines (including 20 Latvian origins) plasticity of seed yield production in changeable environmental conditions. The experiment was carried out in the Agricultural Scientific Centre of Latgale on field trials over the period 2010-2013. The aim of this study was evaluated plasticity in changeable environmental conditions for 29 flax varieties and lines (including 20 Latvian origins). According to 4 years results was to establish the nature of relation between seed yield and hydrothermal coefficient (HTC), and seed yield and another yield components of flax. Apart from the changing conditions highest seed yield were produced from a varieties ‘Lirina’ (2.54 h <sup>-1</sup>t), high seed oil content from variety ‘Amon’ (53.03%). Positive and significant relationships were found between seed yield and HTC ‘T30-28-6-94’(r=+0.98*), ‘German Serenade’ (r=+0.95*) and ‘Scorpion’ (r =+0.95*).

  • Publication . Article . Conference object . 2015
    Open Access English
    Authors: 
    Ļubova Komlajeva; Aleksandrs Adamovics;
    Publisher: Rezeknes Augstskola

    Flax is cultivated on small areas in Latvia. Flax gives dual-purpose production – fibre and seeds. Latvian flax has a high fibre and seed quality. The quantity of flax fibre and seed yield depends on many factors. Several qualitative and quantitative traits, such as technical stem length, resistance to lodging, vegetation period, yield of straw and seeds, fibre and oil content and quality were evaluated. For the further development of Latvian economy flax varieties and hybrids of Latvian origin are an important goal. Fibre flax varieties 'Blue di Riga', 'Priekuļu 665', 'Ošupes 30' and breeding lines 'S-64-17-93' and 'L11-11/11-94' are valuable material containing a qualitative and quantitative indicators of variety. 92 Latvian accessions of flax hybrids have been evaluated, and 12 accessions with the best seed and straw yield have been selected for further DNA analysis. This will simplify and accelerate the selection of new valuable hybrids that will provide particular advantages in agriculture. The genetic analysis of DNA determines the kinship and diversity of flax varieties and breeding lines which can be used further in flax breeding.

  • Publication . Article . Other literature type . 2015
    Open Access English
    Authors: 
    Laura M. E. Sutcliffe; Péter Batáry; Urs G. Kormann; András Báldi; Lynn V. Dicks; Irina Herzon; David Kleijn; Piotr Tryjanowski; Iva Apostolova; Raphaël Arlettaz; +33 more
    Countries: Germany, United Kingdom, Finland, France, Germany, Spain, Switzerland, Croatia, Netherlands, Italy
    Project: EC | LIBERATION (311781), UKRI | To exchange knowledge bet... (NE/J500665/1)

    A large proportion of European biodiversity today depends on habitat provided by low‐intensity farming practices, yet this resource is declining as European agriculture intensifies. Within the European Union, particularly the central and eastern new member states have retained relatively large areas of species‐rich farmland, but despite increased investment in nature conservation here in recent years, farmland biodiversity trends appear to be worsening. Although the high biodiversity value of Central and Eastern European farmland has long been reported, the amount of research in the international literature focused on farmland biodiversity in this region remains comparatively tiny, and measures within the EU Common Agricultural Policy are relatively poorly adapted to support it. In this opinion study, we argue that, 10 years after the accession of the first eastern EU new member states, the continued under‐representation of the low‐intensity farmland in Central and Eastern Europe in the international literature and EU policy is impeding the development of sound, evidence‐based conservation interventions. The biodiversity benefits for Europe of existing low‐intensity farmland, particularly in the central and eastern states, should be harnessed before they are lost. Instead of waiting for species‐rich farmland to further decline, targeted research and monitoring to create locally appropriate conservation strategies for these habitats is needed now. Volkswagen Foundation

  • Open Access
    Authors: 
    Neda Zuļģe; Anna Kāle; Alina Gospodaryk; Kristīne Vēvere; Inga Moročko-Bičevska;
    Publisher: Walter de Gruyter GmbH

    Abstract Apples and pears are among the most important commercial fruit species grown in Latvia. Because of suitability to local climatic conditions, mainly domestic cultivars and cultivars originating in neighbouring countries are grown. The planting material of pome fruits produced and used for establishment of new orchards in Latvia corresponds to the Conformitas Agraria Communitatis standard due to the unavailability of nuclear stock. To establish virus-tested, experimental nuclear stock for apple and pear, one to two years old candidate plants were exposed to thermotherapy at +38 °C for 40 to 70 days. The mother trees and candidate plants before treatment were tested for the presence of the four most widespread pome fruit viruses by RT-PCR. The shoot tips of the heat-treated plants were grafted onto seedling rootstocks and were re-tested for the four viruses by RT-PCR during the next three to five vegetation seasons. Several plants of apple cultivars ‘Dace’, ‘Zarja Alatau’, ‘Rubin’, and ‘Ausma’ remained infected either with Apple chlorotic leaf spot virus, Apple stem growing virus or Apple stem pitting virus after the thermotherapy. Tests on woody indicators were carried out to determine possible presence of graft-transmittable organisms according to EPPO guidelines for the establishment of nuclear stock material for pome fruits.