Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2021
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Abstract
The objective of this study was to determine morphological and anatomical leaf characteristics and stomatal traits of three European (Pyrus communis L.) cultivars, three Asian [Pyrus pyrifolia (Burm. f.) Nakai] pear cultivars together with one interspecies hybrid (P. pyrifolia × P. communis ‘Bartlett’) and link them with the resistance to pathogens. Pear trees were grown under the standard practice without irrigation. Fully developed leaves were picked from the middle part of the extension shoots at the beginning of the July. Leaf traits were measured on leaves picked the same day. Anatomy of leaves was determined under light microscopy (LM) while scanning electron microscopy (SEM) was used for the examination of the stomata cells. Asian pear cultivars (‘Kousui’, ‘Nijisseiki’ and ‘Niitaka’) had much higher leaf parameters (width, length, stem length and leaf area) than the European cultivars (‘Conference’, ‘Williams Bartlett’, ‘Abbate Fetel’) and interspecies hybrid (‘Kieffer Seedling’). Midrib parameters (length and width) were the highest in ‘Kosui’ and ‘Nijisseiki’. Leaves of ‘Kieffer Seedling’ and ‘Abbate Fetel’ were the thickest, mainly due to increased palisade and spongy parenchyma thickness. The leaf stomata density significantly varied among the pear cultivars, ranging from 89.53 stomata mm‑2 (‘Nijisseiki’) up to 134.07 stomata mm‑2 (‘Housui’). SEM proved that Asian pear cultivars and ‘Kieffer Seedling’ shared ‘paracytic’ stomata type, while European pear cultivars had ‘anomocytic’ stomata type. Cluster analysis distinguished pear cultivars into two distinct groups, where European cultivars formed first sub-cluster and Asian together with ‘Kieffer Seedling’ second sub-cluster. Midrib traits and stomata type made a clear separation between the clusters. These results might suggest that thickness of midrib could be a huge barrier for Psylla sp. probing in Asian pears, thus representing one of the key factors in the resistance of these cultivars.
Abstract
Denne rapporten gjev eit litteraturoversyn ved ulike sider av næringsopptaket av ulike mineral og tilførsel til epletre. Det er omtalt dei fysiologiske sidene av næringsopptaket hjå grunnstammer og sjølve sorten, transporten gjennom sil- og vedvev og funksjonen til dei ulike minerala i epletreet. Bladanalysar er eit viktig diagnoseverktøy for vurdering av næringsstatusen i treet. Terskelverdiar for dei ulike minerala er vurderte og tiltak for å retta opp eventuelle mangelsymptom ved hjelp av eit bladgjødslingsprogram. Tilsvarande er eigenskapar ved jorda vurderte, normer for jordanalysar omtalte og tilråding om kalking. Siste bolken omhandlar ulike måtar og mengder for å tilføra gjødsel til frukthagen. Dette gjeld gjødsling til jorda, gjødselvatning i dropevatningsystemet i trerekkja og bladgjødsling.
Abstract
Denne rapporten omhandlar resultat frå feltforsøk med epletre i vekstsesongane 2016 - 2020 ved NLR Viken i Lier og NIBIO Ullensvang. Føremålet med dette prosjektet var å stimulera til auka produksjon av norske eple med god fruktkvalitet dyrka på ein effektiv måte. Det vart gjennomført feltforsøk med kjemisk tynning under blomstringa og på karten med bruk av ulike bioregulatorar, mekanisk tynning med maskin under blomstringa, rotskjering med kniv påmontert traktor, utprøving av vekstregulatoren Regalis og gjødselvatning til to eplesortar. Kontrollert gjødseltilføring med epletre i potter i plasthus vart gjennomført ved Nibio Særheim. Målsetjinga heile tida var å gjera forsøk med miljøvennlege teknikkar til å gjødsla epletre optimalt for å auka den generelle fruktkvaliteten og heva andelen av årleg klasse 1 kvalitet. Dessutan var det viktig å nytta bærekraftige metodar for å redusere skotveksten og regulera avlinga i trea for å oppnå rett fruktsetjing under norske vilkår.
Authors
Teresa Barreneche Maria Cárcamo de la Concepción Marine Blouin-Delmas Matthew Ordidge Hilde Nybom Gunars Lacis Daina Feldmane Jiri Sedlak Mekjell Meland Hedi Kaldmae Kersti Kahu Zsuzsanna Bekefi Sanda Stanivukovic Gordana Đurić Monika Høfer Martin Galik Elisabeth Schüller Andreas Spornberger Sorina Sirbu Pavlina Drogoudi Ana Christina Agulheiro-Santos Ossama Kodad Ales Vokurka Marc Lateur Felicidad Fernandez Fernandez Daniela Giovannini José Quero-GarcíaAbstract
Sweet cherry (Prunus avium L.) is a temperate fruit species whose production might be highly impacted by climate change in the near future. Diversity of plant material could be an option to mitigate these climate risks by enabling producers to have new cultivars well adapted to new environmental conditions. In this study, subsets of sweet cherry collections of 19 European countries were genotyped using 14 SSR. The objectives of this study were (i) to assess genetic diversity parameters, (ii) to estimate the levels of population structure, and (iii) to identify germplasm redundancies. A total of 314 accessions, including landraces, early selections, and modern cultivars, were monitored, and 220 unique SSR genotypes were identified. All 14 loci were confirmed to be polymorphic, and a total of 137 alleles were detected with a mean of 9.8 alleles per locus. The average number of alleles (N = 9.8), PIC value (0.658), observed heterozygosity (Ho = 0.71), and expected heterozygosity (He = 0.70) were higher in this study compared to values reported so far. Four ancestral populations were detected using STRUCTURE software and confirmed by Principal Coordinate Analysis (PCoA), and two of them (K1 and K4) could be attributed to the geographical origin of the accessions. A N-J tree grouped the 220 sweet cherry accessions within three main clusters and six subgroups. Accessions belonging to the four STRUCTURE populations roughly clustered together. Clustering confirmed known genealogical data for several accessions. The large genetic diversity of the collection was demonstrated, in particular within the landrace pool, justifying the efforts made over decades for their conservation. New sources of diversity will allow producers to face challenges, such as climate change and the need to develop more sustainable production systems.
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No abstract has been registered
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No abstract has been registered
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No abstract has been registered
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No abstract has been registered
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Norwegian plum production is characterized by climatic limitations, different flowering time, deficiently of wholly-adapted cultivars and appropriate pollen donors for cultivars that can be grown in this region. This study evaluated the progamic phase of fertilization and fruit set in four European plum cultivars (´Mallard´, ´Edda´, ´Jubileum´, and ´Reeves´) after crossing with different pollinizers over two years (2018/2019). Reproductive parameters, in vitro pollen germination, number of pollen tubes in the upper part of the style and locule of the ovary, number of pistils with ovule penetrated by pollen tube, fruit set in all crossing combinations, and fruit set in open pollination of pollen recipient cultivars showed different adaptability of both recipient and donor cultivars to the specific ecological conditions prevailing in Western Norway. The pollinizers ´Victoria´, ´Opal´ and ´Č. Lepotica´ proved to be a very good pollinizers for cultivar ´Jubileum´, while pollinizers ´R. C. Souffriau´ and ´Valor´ for the cultivar ´Reeves´. Cultivars ´Opal´, ´R. E. Prolific´ and ´Mallard´ are excellent pollinizers for ´Edda´ in conditions of higher temperatures during flowering period and post-flowering period. Cultivar ´Č. Lepotica´ proved to be the best pollinizer for ´Edda´ in conditions when the temperatures were lower. Cultivars ´Opal´ and ´R. E. Prolific´ can be considered as good pollinizers for ´Mallard´.