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.
2021
Forfattere
Mekjell Meland Milica Fotiric Aksic Radosav Cerovic Oddmund Frøynes Clive Kaiser Frank MaasSammendrag
Norwegian pear (Pyrus communis L.) production has been in decline for the last 25 years. This was mainly because of old cultivars, with low yields and poor consumer appeal, could not compete against strong competition from imported pears, mainly ‘Conference’. Since 1994, the Norwegian breeding company, Graminor Ltd., has released several new pear cultivars, which have been evaluated at NIBIO Ullensvang, western Norway. The first trial was planted in 1999 and included the Graminor Ltd. cultivars: ‘Ingeborg’, ‘Fritjof’ and ‘Anna’, which were bred by the Norwegian University of Life Sciences. In 2002, a second trial was planted including Graminor Ltd. cultivars: ‘Kristina’, ‘Ingrid’ and ‘Celina’ and these were compared against a control, ‘Clara Frijs’. All scion cultivars were grafted on the semi-vigorous rootstock ‘Brokmal’ and grown for 8 years. In both trials, full bloom (~80% of flowers open) took place between 7 May + 3 days and 15 May + 4 days. Flowering was however, completed within a 7-day period in any one year, ensuring adequate overlap in flowering time between all cultivars. Over the final 4-year period all cultivars were evaluated, ‘Anna’, ‘Fritjof’, ‘Kristina’ and ‘Ingeborg’ all had moderate cumulative yields (64.7, 66.2, 36.1, and 30.4 kg·tree-1, respectively). Fruit weight (212 to 183g) and quality of all these cultivars was acceptable (11.2% ≤ TSS ≤ 11.8%; 0.16% ≤ acidity ≤ 0.22%). However, ‘Fritjof’ had many misshapen fruit and exhibited pre-harvest shriveling in several instances making it unacceptable for commercial plantings. ‘Clara Frijs’ and ‘Celina’ cumulative yields were low (12.5 and 21.2 kg per tree, respectively) and fruit were also small (172 to 161 g, respectively). However, due to the attractive cerise-blush ‘Celina’ (trademarked QTee®) pear is now widely planted in Norway and abroad and grafted on Quince rootstocks.
Forfattere
Per Jarle MøllerhagenSammendrag
Det er ikke registrert sammendrag
Sammendrag
Performance of the Quince rootstocks ‘Adams’, ‘C’ and ‘Eline®’, all grafted with pear cultivars ’Celina’, ‘Ingeborg’ and ‘Kristina’, were compared at the experimental farm of NIBIO Ullensvang, western Norway. Tree vigour, yield, fruit size and fruit quality were evaluated annually for the first seven years. No severe winter damage was observed during these years and none of the trees died. After seven years there were no significant differences in tree size in ‘Celina’ and ‘Ingeborg’ grafted on the different rootstocks, while trunk diameter increase of ‘Kristina’ was significantly larger on ‘Eline®’ than on ‘C’ and intermediate on ‘Adams’. Flower development and fruit set were not affected by rootstocks in any of the three scion cultivars. On average, mature fruit were picked during mid to end September and the trees began producing a small crop in the third season. No alternate bearing pattern was identified. For ‘Celina’ and ‘Kristina’ yield was similar for trees on all three rootstocks. Cumulative yields for the first five cropping years were 31.3 kg tree‑1 for ‘Celina’, 25.9 kg tree‑1 for ‘Kristina’ and 19.4 kg tree‑1 for ‘Ingeborg’. ‘Celina’ produced the highest total number of fruit when grafted on ‘Adams’ or ‘C’. Trees on ‘Eline®’ produced a significantly lower number of fruit in both ‘Celina’ and ‘Ingeborg’. On average for all cultivars, no significant effect of rootstock was observed on average fruit weight during these 5 production years. ‘Eline®’ on average yielded fruit of 165 g for all cultivars while for ‘Adams’ and ‘C’ it was 162 g. Soluble solids concentration was high (11.2% on average) but was not significantly affected by rootstocks. Fruit acidity was similar for all quince rootstocks (0.19-0.21%). The fruit development period between full bloom and harvest showed a clear inverse linear relationship with the average daily temperature. In conclusion, because the trees have not reached their full production none of these quince rootstocks can yet be recommended as the preferred rootstock for pear growing in a cool, mesic northern climate.
Sammendrag
The Norwegian newly bred pear cultivar, ‘Celina/QTee®’, which was launched in 2010, has been released from the Norwegian breeding program. It derived from the combination ‘Colourée de Juillet’ × ‘Williams’. In Norway the flowering is medium to late in May and it ripens in the beginning of September. It has large attractive fruits with red blush and good fruit quality, storability and shelf life. Significant areas of ‘Celina’ cultivars are planted in other countries, mainly Europe. Generally, unfavourable environmental conditions for pear pollination during the Nordic spring can have a very negative effect on the yields in Norwegian pear orchards. Therefore, it is of considerable importance to interplant multiple suitable pollinizer genotypes together with the main cultivar. In order to find the right pollinizers besides following biology of fertilization, pollinizing efficacy using microsatellites were studied at NIBIO Ullensvang, western Norway. In this study, during 2017, seeds from fruits of the pear cultivar ‘Celina’ were extracted. The fruits were randomly harvested from five different orchards located in Ullensvang including NIBIO. Alongside the seeds, leaves were taken from the mother cultivar (‘Celina’) and five pear pollinizer cultivars presented in the orchards (‘Fritjof’, ‘Kristina’, ‘Clara Frijs’, ‘Herzogine Elsa’ and ‘Anna’). Using 11 microsatellite markers, a genetic characterization was conducted on both the seeds and the leaves. The obtained SSR profiles were used for gene assignment analyses. The results of the genetic analyses indicate a very heterogeneous situation regarding pollination. In conclusion, ‘Fritjof’, ‘Kristina’, ‘Clara Frijs’, ‘Herzogine Elsa’ and ‘Anna’ pears had different pollen contributions as pollinizers to ‘Celina’ depending on the investigated orchard. Only one cultivar (‘Herzogine Else’) could be singled out as a major pollen contributor in more than two orchards. Genetic analyses will be repeated in the same orchards, during an additional season, after which more conclusive results will be available.
Forfattere
Per Jarle MøllerhagenSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Mette ThomsenSammendrag
Det er ikke registrert sammendrag
Sammendrag
https://youtu.be/ngVWWIkiU5s
Sammendrag
Det er ikke registrert sammendrag
Populærvitenskapelig – Bruk av fangvekster og jorddekke i grønnsaks produksjon (del 2)
Mette Thomsen
Forfattere
Mette ThomsenSammendrag
Det er ikke registrert sammendrag