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.
2020
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En har i denne studien undersøkt potensialet for å erstatte fossilt drivstoff med elektrisk energi fra batterier og/eller hydrogenbrenselceller i traktorarbeidet på norske gårder. Dette ble gjort med utgangspunkt i seksten små og store modellgårder på Østlandet, i Trøndelag og i Rogaland. Disse var korngårder med og uten husdyr, og melkeproduksjonsbruk. Det årlige dieselforbruket i alle traktordrevne arbeidsoperasjoner ble beregnet og videre tidfestet og fordelt gjennom året. For alle brukstyper var det høye topper med mye traktorarbeid knyttet til pløying og/eller spredning av husdyrgjødsel om våren og til innhøsting og pløying om høsten...
Abstract
BACKGROUND: Bud dormancy is a quantitative condition that is gradually acquired and lost. Better and more convenient methods for assessment of the time of dormancy entrance of woody plants are highly needed. OBJECTIVE: To demonstrate a simple and convenient method for determination of dormancy in woody plants. METHODS: We employed a seasonal series of soft tipping of vigorously growing annual shoots and used the loss of ability of subtending lateral buds to break and grow as a measure of entrance into dormancy. RESULTS: There was a gradual decline in the ability of the buds to burst and grow during the month of July and early August, culminating with a complete loss of this ability. This coincided with the known time of growth cessation and dormancy induction in shoots of intact plants and occurred in the berry shrubs raspberry and black currant and the forest tree silver birch. CONCLUSIONS: The decline and loss of ability of the buds to grow during late summer is a direct expression of the entrance of buds into the state of endodormancy, rendering the tipping method a simple and convenient method for precise determination of the time of entrance into dormancy in woody plants.
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No abstract has been registered
Abstract
After harvest, vegetables go from storing assimilates to break down of assimilates and it is of crucial importance to slow down this process. Controlling the pre-storage period may contribute to maintain high quality in root vegetables during long-term storage. The aim of this 2-years study was to investigate the effect of seven different pre-storage strategies (direct to 0°C vs. down 1°C per day vs. 0.2°C temperature reduction per day and wound healing at 10°C with low/high humidity) on root storability in four cultivars of carrot (Daucus carota subsp. sativus) stored in 2016/2017/2018, swede (Brassica napus) in 2017/2018 and celeriac (Apium graveolens var. rapaceum) in 2017/2018. Mass loss and disease incidences were determined during and after long-term storage (6-7 month) in small-scale stores. Wound healing with low humidity resulted in larger mass loss than the other preharvest strategies in carrot and celeriac. In carrot, slow temperature reduction (0.2°C per day) also resulted in larger mass loss than the other strategies. Significantly higher numbers of infected roots, dominated by licorice rot (Mycocentrospora acerina), tip rot and gray mold (Botrytis cinerea), occurred in carrots stored at 0°C immediately compared to roots with a period of wound healing and slow temperature decline. In celeriac, the incidence of gray mold (Botrytis cinerea) and licorice rot (Mycocentrospora acerina) were significantly reduced with wound healing at low humidity. Storage quality of swede was not affected by pre-storage strategies. This study shows that prestorage strategies affect mass loss and disease incidence in celeriac and carrot during and after long-term storage.
Authors
Mekjell Meland Oddmund Frøynes Milica Fotiric Akšic Naris Pojskic Belma Kalamujic Stroil Lejla Lasic Fuad GasiAbstract
European plum cultivars (Prunus domestica L.) are hexaploid and partially self-fertile or self-sterile requiring compatible pollinizers with overlapping bloom times. Therefore, inter-planting of different pollinizer cultivars is recommended. In order to identify successful pollinizers of the plum cultivars ‘Edda’, ‘Opal’ (self-fertile), ‘Jubileum’, ‘Reeves’, ‘Mallard’, ‘Avalon’, ‘Cacanska Lepotica’ (self-fertile), and ‘Valor’, 60 fruits per cultivar were collected from nine orchards in 2017 and 2018, all of which were located in Ullensvang, western Norway. DNA extraction was subsequently conducted from the obtained embryos, followed by genetic characterization using seven microsatellite markers. Tissue samples from all possible pollinizers were collected during the summer of 2017 and the same DNA approach was conducted. Results showed that ‘Opal’ was the most successful pollinizer among the investigated plum cultivars. The main exception was ‘Cacanska Lepotica’, which consistently displayed very high level of self-pollination. The most successful foreign pollinizer of ‘Opal’ was ‘Mallard’. However, in more than two thirds of embryos extracted from ‘Opal’ fruits self-fertilization was determined. ‘Reeves’ was identified as the most successful pollinizer among embryos collected from ‘Valor’. Among the five cultivars (‘Edda’, ‘Jubileum’, ‘Reeves’, ‘Mallard’, and ‘Avalon’) that did not display self-pollination, the pollinizer success rate of ‘Opal’, ranged from 36.5% (‘Mallard’) to 93.5% (‘Edda’) in 2017, while in 2018 this rate ranged from 43.5% (‘Jubileum’ and ‘Reeves’) up to 96.5% (‘Edda’). Overall, genotyping embryos using SSRs (simple sequence repeats) proved an effective method in determining the success rate of individual pollinizers among European plum cultivars.
Abstract
In order to identify successful pollinizers of plum cultivars ‘Edda’ and ‘Opal’, 60 mature open pollinated fruit were collected from these two cultivars in autumn 2017. The fruits were harvested in three different orchards located in Ullensvang, the main fruit production area in Norway. After the harvest, kernels were separated from the fruit and used for the extraction of single embryos located within each kernel. At the same time, leaves were collected from the plum cultivars ‘Edda’ and ‘Opal’, as well as from all other plum cultivars present at the location and nearby orchards (‘Mallard’, ‘Jubileum’, ‘Reeves’, ‘Avalon’, ‘Valor’, ‘Cacanska Lepotica’ and ‘Herman’). DNA extraction was carried out for the embryos and leaves, and were used for genotyping using seven microsatellite markers. The microsatellite data were used for conducting paternity analyses based on a log likelihood ratio, where the fingerprint information from the leaves were the possible pollen donors available at the location. The results revealed within all examined orchards that the most successful pollinizer of ‘Edda’, a self-sterile cultivar, was ‘Opal’. The most successful foreign pollinizer of ‘Opal’ was ‘Mallard’. However, more than two thirds of embryos extracted from ‘Opal’ fruits did not present any alleles not already identified in ‘Opal’, which was expected considering that this plum cultivar was known to be self-fertile. European plums are hexaploid making its allele callings and paternity tests rather complicated. However, the approach used in this study gave clear answers regarding the most successful pollinizers.
Abstract
The triploid pear cultivar ‘Ingeborg’ is currently the main commercial pear cultivar grown in Norway. However, fruit set and subsequent yields of this cultivar have proven to be variable and overall rather low. In order to promote the fruit set, different bioregulators were applied during and after bloom and compared with an untreated control. Investigations were done during the period 2017-2018, at NIBIO Ullensvang, western Norway. Different dosages of both gibberellins (GA3, trade name GIBB 3, 10% active ingredient (a.i.) and GA4/7, trade name Novagib®, 1% a.i.) were applied at full bloom and at petal fall. Additional applications of the growth retardant prohexadioneCa (trade name Regalis®, 10% a.i.) were applied twice, when bourse shoots had 3-5 leaves and after one month later. Ethephon (Cerone (480 g a.i. L-1)) was applied three times starting about 7 days after petal fall with ca. 7- to 10-day intervals. All gibberellin applications significantly increased fruit set compared to the untreated control. One single application with GA3 (3 g ha-1) almost tripled the fruit number per 100 flower clusters when compared with the control (136 and 46, respectively). The yield response was similar (16.8 to 9.6 kg tree-1, respectively). Similar results occurred with one application of GA4/7 (12 g ha-1) with the same crop load level, and the fruit weights were similar to the control (130 g). Prohexadione-Ca treatments significantly reduced shoot growth of the pear trees. Two treatments with 125 g ha-1 or one treatment of 250 g ha-1 reduced the growth by ~35% but had no significant effect on fruit set and yield. The multiple ethephon applications (275 mL ha-1 in total) had no effect on both set and shoot growth, and return bloom compared to the untreated or gibberellin treated trees.
Authors
Fuad Gasi Oddmund Frøynes Belma Kalamujic Stroil Lejla Lasic Naris Pojskic Milica Fotiric Aksic Mekjell MelandAbstract
The diploid Celina/QTee® (‘Colorée de Juillet’ × ‘Williams’), one of the most promising pear cultivars developed by the Norwegian breeding program Graminor, was launched in 2010. In Norway, the flowering is medium to late, while the fruits ripen in the beginning of September. The fruits are attractive with an intense red blush (50%) on a green background. Although, ‘Celina’ is cultivated in the most climatically suitable regions for fruit cultivation, present in Norway, unfavorable environmental conditions for pear pollination can have a very negative effect on fruit set and consequent yield. The aim of this study was to determine the S-alleles of ‘Celina’, as well as its frequently used pollinizers, and, through paternity testing of ‘Celina’ seeds, give a recommendation regarding the most important pollinizers of this pear cultivar. In order to accomplish this, ‘Celina’ and its potential pollinizers were all S-genotyped. After harvest, seeds collected from ‘Celina’ fruit in 2017 and 2018 were genotyped using eleven microsatellite markers. Genomic DNA was also extracted from leaf material collected from ‘Celina’, as well as from five pear cultivars used as pollinizers in the three examined orchards, and analyzed using the same marker set. Subsequently a simple sequence repeat (SSR) database was constructed and used for gene assignment analyses with the aim of quantifying pollen donor contribution from individual pollinizers. The obtained results indicate that ‘Anna’, the only examined pollinizer that was fully cross-compatible with ‘Celina’, together with ‘Fritjof’, the genotype which had the highest flowering overlap with ‘Celina’, proved to be the most successful pollinizers across all seasons and orchards. Although both cultivars were ubiquitous in the examined orchards, either as planted trees or as branches introduced during the flowering period, they were the most abundant pollinizers in only one orchard each. It is therefore possible to conclude that pollinizer abundance has a secondary significance in pollinizer success within investigated ‘Celina’ orchards.