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.
2011
Sammendrag
Food production is the largest consumer of mined phosphorus (P) worldwide.
Forfattere
Anne Linn Hykkerud Steindal Jørgen Mølmann Tor J. Johansen Gunnar BengtssonSammendrag
Det er ikke registrert sammendrag
Forfattere
Theo RuissenSammendrag
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Forfattere
Theo RuissenSammendrag
Debattinnlegg forskningsmetodikk-forskningsetikk
Forfattere
Theo RuissenSammendrag
Debattinnlegg genmodifisering
Forfattere
Anne Linn Hykkerud Steindal Jørgen Mølmann Tor J. Johansen Gunnar BengtssonSammendrag
Det er ikke registrert sammendrag
Forfattere
Tor J. JohansenSammendrag
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Forfattere
Tor J. JohansenSammendrag
Det er ikke registrert sammendrag
Forfattere
Tor J. JohansenSammendrag
Production of healthy, vigorous potato plants and a high yield of good quality under varied environmental conditions require quality seed tubers. Quality may be divided in two important factors, tuber health and physiological quality. Physiological quality (number and vigour of sprouts and stems, growth and yield potential) is determined by the size of the seed tuber, the physiological status of the seed and interactions between these two factors. The physiological status of the seed is usually called physiological age. This may be defined as “the stage of development of a tuber, which is modified progressively by increasing chronological age, depending of growth history and storage conditions” (Struik and Wiersema 1999, Seed potato technology). The sequence of stages of development are dormancy, apical sprouting, normal sprouting with a few or multiple branched sprouts, senility and finally incubation with direct formation of daughter tubers on the seed tuber. Each stage has a strong influence on vigour and yield potential of the seed. Temperature is the most important environmental factor that affects physiological age in seed potatoes, either during growth of the mother plant, or during storage. Unfortunately, physiological age is hard to measure directly, and indirect methods, based on sprout development, sprout characteristics and sprouting capacity are normally used. In Norway, several studies of the impact of geographic origin, growth temperatures, day-lengths, and pre-storing temperatures on vigour and yield potential have been performed the last10 years. One of the aims has been to study the “northern vigour claims”, which implies superiority of seed produced in northern latitudes over seed produced in southern latitudes. In summary the results showed: Low temperature (9 ºC) gave a small but positive effect on progeny growth vigour and yields compared to a higher temperature (15 ºC) in cv. ‘Troll’. Day-length (12 or 24 hrs) did not affect the results significantly. In a study with average temperatures of 9, 15 and 18 ºC, 12 and 24 hrs day-lengths, the physiologically oldest tubers originated from the lowest growth temperatures. In a three-year field study at distant sites in Norway (lat. 59-70) the results showed no superiority of seed from any latitude, regarding vigour and yields. In a controlled climate study at 9, 15 and 21 °C, results showed that dormancy may be shortened by low grow temperatures, and similarly by low post-harvest temperatures (4 °C). The scientific fundament of “northern vigour” is still not clear, but as a statement it may call attention to the generally good quality of northern seed.
Sammendrag
Det er ikke registrert sammendrag