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.
2002
Abstract
No abstract has been registered
Abstract
The purpose of this study was to test the activity of gibberellins and auxins for induction of parthenocarpic fruit development in cloudberry, Rubus chamaemorus L., a dioecious, northern wild berry with potential for cultivation. Plant hormones were applied directly to open flowers, either dissolved in ethanol or as an aqueous spray. Of the tested gibberellins (GA1, GA3, GA4, dimethyl-GA4, GA5, GA9, GA19, GA20 and GA24) only GA1, GA3, GA4 and dimethyl-GA4 were active and induced fruit development comparable to development of pollinated fruits. Lack of activity of GA20 and GA9, the immediate precursors of GA1 and GA4, respectively, suggests that 3 b-hydroxylation of gibberellins can be inhibited in unpollinated flowers of cloudberry. Auxin treatments induced an initial fruit development, but did not result in ripe berries. Based on these results, use of transgenic methods to regulate gibberellin or/and auxin biosynthesis in carpels of cloudberry could be used to develop a parthenocarpic cloudberry.
Abstract
Årleg turrstoffproduksjon vart estimert frå åtte år gamle epletre med sortane "Fuji", "Royal Gala" og "Braeburn" poda på grunnstamma M9 og forma som slank spindel. Både frisk- og turrstoffproduksjon auka liniært med mengda av ljos som vart oppfanga i trea. Denne samanhengen tilsvarar ei avling på 16.9 tonn pr. daa med ei ljosoppfanging på 90 %. Energien som vart omdanna frå ljos i vekstsesongen til turrstoff i New Zealand var tilsvarande som i England. Skilnaden mellom desse to landa er at New Zealand har ein lengre vekstsesong og høgare innstråling. Turrstoffproduksjonen var fordelt til frukt, treaktig vev og blad med ei fordeling til frukt på 74, 72 og 63% for dei tre sortane "Braeburn", "Fuji" og "Royal Gala".
2001
Authors
Mekjell MelandAbstract
An intensive field planting of `Edda", "Opal" and "Mallard" plum trees (Prunus domestica L.) all grafted on the semidwarf rootstock St. Julien A was established in 1993 at Ullensvang Research Centre, western Norway at 60 ° North. The objectives were to evaluate four different single row planting systems (vertical axis, free spindle, hedgerow and Y-trellis) and three planting densities ( 0.5, 1.0, 1.5 x 4 m for the Y-trellis and hedge trees and 2.0 x 4 m for the central leader trees) in a northern climate. These planting distances give a range of tree density of 1250 - 5000 trees per ha. The experiment gave a small yield in the third leaf on all canopy systems. During the first four cropping years, the yields/ha were positively correlated with tree density. Cumulative yield per hectare was highest on the Y-trellis and hedge trees with the highest density (5000 trees per ha). In the fourth leaf, the Y-trellis trees gave 15 tons per hectare. No differences in fruit size or the soluble solids content among canopies or densities were found.
Abstract
The cherry cultivars "Van", "Ulster" and "Burlat" grafted on the rootstocks seedling, `Colt" and `Gisela 5" were evaluated for important fruit quality parameters at Ullensvang Research Centre during the 1998 season. The largest fruit size was found on the cultivar/rootstock combinations `Van"/seedling, `Ulster/Colt" and `Burlat/Gisela 5". Other parameters like fruit firmness, stone weight, soluble solids, titratable acids and pH of the fruit juice were registered as well.
Abstract
No abstract has been registered
2000
Authors
Michel VerheulAbstract
No abstract has been registered
1998
Authors
Olavi Junttila Jorunn Elisabeth Olsen Jarle Halvard Nilsen Inger Martinussen Thomas Moritz Maria Eriksson Olle Olsson Göran SandbergAbstract
Photoperiodic effects on woody plants were reported already by Gardner and Allard in 1923 and comprehensive studies during the ’50s confirmed the role of photoperiod as an important environmental regulator of growth and growth cessation in many northern tree species (Nitsch, 1957; Wareing, 1956). In woody plants cessation of apical growth is a prerequisite for cold acclimation (Weiser, 1970) and photoperiod, as a factor controlling growth cessation, is therefore an important environmental signal for initiation of cold acclimation. In many cases a proper timing of acclimation and deacclimation, in respect to annual variation of temperature conditions, is more critical for winter survival than the maximum level of frost hardiness. Also in such coniferous species where cessation of apical growth is not controlled by photoperiod, short photoperiod is necessary for good cold acclimation, low temperature causes no or only a limited level of hardiness if combined with long day conditions (Schwarz, 1970; Aronsson, 1975; Christersson, 1978; Jonsson et al., 1981). Thus, photoperiod may have both an indirect, through induction of growth cessation, and a more direct influence on cold acclimation in woody plants.
Academic – Rain covers against cracking for sweet cherry orchards
Mekjell Meland, Kjersti Skjervheim
Abstract
No abstract has been registered
Authors
Mekjell MelandAbstract
No abstract has been registered