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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.

2016

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Abstract

Mixtures and pure stands of perennial ryegrass, tall fescue, white clover and red clover were grown in a three-cut and a five-cut system in southern Norway, at a low fertilization rate (100 kg N ha−1 year−1). The nutritional quality (annual weighted averages) of the dried forage from the two-first harvesting years was analysed. There was no significant effect of species diversity on crude protein (CP) concentration. In the three-cut system, we found a significant species diversity effect leading to 10% higher concentrations of acid detergent fibre (ADF), 20–22% lower concentrations of water-soluble carbohydrate (WSC) and 4% lower net energy for lactation (NEL) concentrations in mixtures compared with pure stands (averaged across the two-first years). In the five-cut system, similar effects were seen in the first year only. This diversity effect was associated with a reduction in WSC and NEL concentrations and an increase in ADF, NDF and CP concentrations in the grass species, and not in red clover, when grown in mixtures. This is thought to be a combined result of better N availability and more shading in the mixtures. Species diversity reduced the intra-annual variability in nutritional quality in both cutting systems.

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Abstract

1. Fire is a widespread management practice used in the maintenance of European heathland. Frequent prescribed burns in small patches have been shown to benefit carabid communities; however, how fire favours specific life-history traits is poorly understood. 2. In this study, we identify characteristic species of the successional stages within heathlands, and find the traits which are characteristic of species in burnt areas versus areas dominated by older heath stands. 3. We identify 10 species as indicator species for heathland in the pioneer stage (0–5 years old); Amara lunicollis, Bembidion lampros, Calathus fuscipes, Carabus problematicus, Cicindela campestris, Nebria salina, Notiophilus aquaticus, Poecilus cupreus, P. lepidus and P. versicolor. Dyschirius globosus is identified as an indicator for the building stage (6–14 years old), and Carabus violaceus as an indicator for the mature stage (15–25 years old). 4. Moisture preference and diet are identified as traits that determine species response to prescribed fire. Collembolan specialists and species with no moisture preference are shown to be most abundant in burnt patches, whereas generalist predators and species with a high moisture preference are less tolerant of fire. 5. Knowledge of species sorting along a prescribed fire gradient can provide valuable information for heathland conservation.

Abstract

Fusarium and Microdochium may cause seedling blight and poor germination of cereal seeds. However, indications of poor survival of Fusarium in seed and improved germination after some months of storage have been observed. A study was carried out to investigate if seed storage can contribute to improved seed quality. Samples from seed lots of barley, oats and spring wheat were tested for germination capacity and Fusarium /Microdochium infection frequencies a few days after harvest, and after 5, 12 and 15 months of storage. In barley, the average germination percentage increased slightly, from 92% at harvest to 95% after five months of storage. In oats, the average germination percentage increased from 82% to 85% during the first five months. In spring wheat, the average germination percentage was reduced from 81% at harvest to 67% after five months. In barley and oats, average Fusarium /Microdochium frequencies were reduced during storage, with the highest reduction observed during the first five months (from 50% to 37%, and from 60% to 46%, barley and oats respectively). In spring wheat, no significant reduction in average infection level was recorded (58% at harvest, 50% after 15 months of storage). There was however, variation between seed lots in all three cereal species in both germination percentage and Fusarium /Microdochium frequencies during the storage period. It is concluded that storage of barley and oats seeds for 5 months after harvest may in some cases increase the seed quality and thereby meet the certification requirements of minimum 85% germination.