Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2016
Forfattere
Håvard SteinshamnSammendrag
Det er ikke registrert sammendrag
Forfattere
Håvard SteinshamnSammendrag
Det er ikke registrert sammendrag
Forfattere
Håvard SteinshamnSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Bénédicte Wenden José Antonio Campoy Julien Lecourt Gregorio López Ortega Michael Blanke Sanja Radičević Elisabeth Schüller Andreas Spornberger Danilo Christen Hugo Magein Daniela Giovannini Carlos Campillo Svetoslav Malchev José Miguel Peris Mekjell Meland Rolf Stehr Gerard Charlot José Quero-GarcíaSammendrag
Professional and scientific networks built around the production of sweet cherry (Prunus avium L.) led to the collection of phenology data for a wide range of cultivars grown in experimental sites characterized by highly contrasted climatic conditions. We present a dataset of flowering and maturity dates, recorded each year for one tree when available, or the average of several trees for each cultivar, over a period of 37 years (1978–2015). Such a dataset is extremely valuable for characterizing the phenological response to climate change, and the plasticity of the different cultivars’ behaviour under different environmental conditions. In addition, this dataset will support the development of predictive models for sweet cherry phenology exploitable at the continental scale, and will help anticipate breeding strategies in order to maintain and improve sweet cherry production in Europe.
Sammendrag
The European plum cultivar 'Opal', widely grown in Scandinavia, frequently initiates too many flowers and set too many fruits. If excess fruitlets remain on the trees until harvest, the crop consists of small, unmarketable fruits of low fruit quality and return bloom will be reduced. The current study investigated effects of different crop loads established at blossom and fruitlet stages on yield, fruit quality and return bloom. For two seasons starting in 2008 on mature 'Opal'/'St. Julien A' trees, two crop loads 50 and 25% flowers reduced were established at full bloom and at 10-12 mm fruitlet size and compared with an un-thinned control treatment. Treatments were applied on single whole trees in a randomized complete block design with six replications. Spindle trees spaced at 3.0×5.0 m were selected for uniformity in growth habit, flowering intensity and trunk cross sectional area. Final fruit set varied from 63% on the control trees to 18% when thinned at bloom. Yield was negatively correlated with the fruit set response. Thinning at the fruitlet stage resulted in smaller fruits at the same crop level compared to flower thinning. Fruit quality parameters characterized by bright yellow skin background colour, red surface colour and the concentrations of soluble solids increased significantly as the crop load was reduced. Other fruit quality parameters like percentage acidity were not significantly different and did not show a clear response to the thinning. Return bloom was promoted most when trees were thinned at bloom the year before.
Sammendrag
European plum cultivar Jubileum (Prunus domestica L.) blooms abundantly most years and too many fruit can be set if flowers and/or fruitlets are not properly thinned. In 2007, 2008 and 2009, mature ‘Jubileum/St. Julien A’ trees were treated with ethephon either at full bloom, at concentrations of 250, 375 and 500 mg/l or when fruitlets averaged ~12 mm in diameter at concentrations of 125, 250 and 375 mg/l. In general, flower-thinning treatments reduced fruit set significantly. Fruit set decreased with increasing ethephon concentrations, and the highest rate of ethephon applied either at full bloom (500 mg/l) or post bloom (375 mg/l) resulted in excessive over-thinning. Up to 375 mg/l of ethephon was required at full bloom whereas only 125 mg/l of ethephon was required post bloom for marked fruitlet thinning. Yields confirmed the fruit set response and yield reductions were significant. In most years, all thinning treatments resulted in fruit larger than 38 mm in diameter compared to fruit from unthinned control trees. Fruit quality, characterized by blue surface color and soluble solids content was generally higher and increased significantly with the reduction in crop load. Fruit firmness of fruit from all ethephon applications was lower than that of the fruit from unthinned control trees. In contrast, titratable acidity did not show a clear response to ethephon thinning. Return bloom the following year was mostly unaffected by all ethephon applications compared to the control. In conclusion, an ethephon application at a rate of up to 375 mg/l applied at full bloom will result in adequate thinning of ‘Jubileum’ plums and achieved a target of about 10- 15 % reduction in fruit set. When weather conditions are not conducive during flowering, a post bloom ethephon application at 125 mg/l may be applied however, this should only be considered in years of excessive flowering and as a last resort.
Sammendrag
When establishing an apple orchard it is important to stimulate the growth of young trees to fill up their allotted space in the row and minimize the time to come into full production with high quality fruit. In May 2012 two-year-old 'Summerred'/'M.9' knip trees were planted at the experimental farm at NIBIO Ullensvang, western Norway. The planting distance was 4×1 m (2500 trees ha-1). Three fertigation schemes were established (zero; low - 0.15 g N m-1 row day-1, and high nitrogen - 0.30 g N m-1 row day-1) and two crop loads allowed (low and high). In the year after planting the crop loads were limited to zero and five apples tree-1, respectively. In the third leaf the crop loads were adjusted by hand to 15 apples and 30 apples tree-1, respectively. The experimental design was a randomized blocks with four replications and 10 trees treatment-1. No significant effects of N-fertigation on soil NO3-, NH4+ or N-min contents were found. However, N-fertigation increased the leaf nitrogen content the whole season and leaf N were ≥ than the standard adequacy range (1.5-2.0%). Trees reached the desirable height of 3 m in the third leaf. Trunk circumference and number of branches per tree increased from second to third leaf, but were not significantly influenced by the N-fertigation. In the third leaf the high crop load trees yielded 7 kg tree-1 (17.5 t ha-1) and the low crop load 4 kg tree-1. Fruit weights were negatively correlated with the crop loads. Small differences in fruit quality attributes were found. Return bloom was not affected after the second leaf. However, the high crop load in the third leaf clearly reduced the amounts of return bloom in 2015, irrespective of the amount of N-fertigation.