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.
2018
Authors
Victor Phani Tagginahalli N. Shivakumara Keith Davies Uma RaoAbstract
Mucins are highly glycosylated polypeptides involved in many host–parasite interactions, but their function in plant-parasitic nematodes is still unknown. In this study, a mucin-like gene was cloned from Meloidogyne incognita (Mi-muc-1, 1125 bp) and characterized. The protein was found to be rich in serine and threonine with numerous O-glycosylation sites in the sequence. Quantitative real-time polymerase chain reaction (qRT-PCR) showed the highest expression in the adult female and in situhybridization revealed the localization of Mi-muc-1 mRNA ex-pression in the tail area in the region of the phasmid. Knockdown of Mi-muc-1 revealed a dual role: (1) immunologically, there was a significant decrease in attachment of Pasteuria penetrans en-dospores and a reduction in binding assays with human red blood cells (RBCs), suggesting that Mi-MUC-1 is a glycoprotein present on the surface coat of infective second-stage juveniles (J2s) and is involved in cellular adhesion to the cuticle of infective J2s; pretreatment of J2s with different carbohydrates indicated that the RBCs bind to J2 cuticle receptors different from those involved in the interaction of Pasteuria endospores with Mi-MUC-1; (2) the long-term effect of RNA interference (RNAi)-mediated knockdown of Mi-muc-1 led to a significant reduction in nematode fecundity, suggesting a possible function for this mucin as a mediator in the interaction between the nematode and the host plant.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Angela Koort Ulvi Moor Priit Poldma Clive Kaiser Marge StarastAbstract
The aim of the study was to determine the effect of modified atmosphere (MA) packages on the external quality of organically grown lowbush blueberry and half-highbush blueberry (’Northblue’) and the nutritional value of the fruits. Fruits were divided into plastic punnets and stored as follows: regular atmosphere (RA), punnets without packing; punnets sealed in a low-density polyethylene (LDPE, Estiko) bag; punnets sealed in an Xtend® blueberry bag (Stepac). Fruits were stored at 3 ± 1 ◦C. Compared to RA conditions, the Xtend® package prolonged the postharvest life for 15 days for lowbush and 9 days for half-highbush blueberries. Fruit dry matter (DM) and titratable acidity (TA) were higher in the Xtend® package. Fruit SSC decreased in the LDPE packages and increased in the Xtend® packages during storage. Based on the decreased soluble solids content (SSC) and titratable acidity (TA) ratio (SSC:TA) values during storage, it can be concluded that the taste of the fruits became sourer in all packages. Anthocyanin biosynthesis of lowbush blueberries was suppressed in MA, but this effect was not noticed for ‘Northblue’. Regarding fruit firmness, shrivelling, and decay, there were significant differences between the MA packages, but the genetic differences were more important: half-highbush blueberry fruits were firmer and less shrivelled.
Authors
Anna Maria Vettraino Alberto Santini Christo Nikolov Jean-Claude Grégoire Rumen Tomov Andrei Orlinski Tiit Maaten Halldors Sverrisson Bjørn Økland René EschenAbstract
The sentinel plants concept responds to the need for new strategies to identify and study potential plant pests (including pathogens) and assess associated risks before their introduction to other continents. However, even if very promising, this tool is not yet implemented on a large scale, partially because it requires adequate planning, long-term funding, strong local links and reliable collaborators. In addition, a wider implementation of sentinel plantations and sentinel nurseries requires knowledge of regulations and procedures regarding the possibilities for their establishment in different countries. In order to achieve this objective, a questionnaire survey was conducted in 2016, to which more than 40 countries around the world responded. The results reveal that many countries have few regulations specifically concerning the import of propagation material, making import of this relatively low-risk material easier than the import of larger living plants that may have been more exposed to pests in the exporting country. The planting of alien woody plants in the environment is possible for scientific purposes in most countries as exemption from general phytosanitary import requirements, but the import and planting of alien plant species may be regulated by different government departments. We will present the outcomes of this study, which will be useful to facilitate the selection of locations for future sentinel plants and may provide guidance on the rules for import of plant propagation material for the establishment of sentinel plants and sentinel nurseries in different countries.
Abstract
No abstract has been registered
Authors
Bjørn ØklandAbstract
No abstract has been registered
Authors
Bjørn ØklandAbstract
No abstract has been registered
Authors
Bjørn ØklandAbstract
No abstract has been registered
Abstract
The fungus Neonectria fuckeliana has become an increasing problem on Norway spruce (Picea abies) in the Nordic countries during recent years. Canker wounds caused by the pathogen reduce timber quality and top-dieback is a problem for the Christmas tree industry. In this study, four inoculation trials were conducted to examine the ability of N. fuckeliana to cause disease on young Norway spruce plants and determine how different wound types would affect the occurrence and severity of the disease. Symptom development after 8–11 months was mainly mild and lesion lengths under bark were generally minor. However, N. fuckeliana could still be reisolated and/or molecularly detected. Slow disease development is in line with older studies describing N. fuckeliana as a weak pathogen. However, the results do not explain the serious increased damage by N. fuckeliana registered in Nordic forests and Christmas tree plantations. Potential management implications, such as shearing Christmas trees during periods of low inoculum pressure, cleaning secateurs between trees, and removal and burning of diseased branches and trees to avoid inoculum transfer and to keep disease pressure low, are based on experiments presented here and experiences with related pathogens.