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.
2004
Forfattere
Mekjell MelandSammendrag
Alternate bearing is a major problem for the Norwegian apple industry. Due to over-cropping one year where fruit size and quality are reduced, the trees are likely to turn into a pattern with high and low yield every second year. This inconsistent yield pattern provides problem for both the growers and the market. Commercial practise is to remove the excessive flowers or fruitlets by chemicals or by handthinning. The only officially registered agents for apple thinning are ethephon and ammoniumthiosulphat. The growers find them unpredictable in use and more knowledge is wanted in order to give more precisely thinning recommendations. A new project started at Ullensvang Research Centre in 2003. It will last for three years and focus on optimising the crop loads and test different thinning agents under bloom and at different fruitlet stages. Different crop levels will be established during and after bloom by hand adjusted by trunk cross sectional area. The experimental trees will be monitored during a 3-year period. Traditional pomological observations will be registered included storage of the fruits where fruit quality will be measured. Leaf areas per tree will be calculated using an area meter. In addition different thinning chemicals will be tested according the program to the working group of European Fruit Research Institute Networks. Emphasis will be put on concentration and thinning periods of the agents ethephon, ammoniumthiosulphat and compounds that could be approved for organic growing like colza oil. Results from the 2003 season will be presented.
Sammendrag
Trees of `Discovery" apples growing on dwarf and semi-dwarf rootstocks were assessed in field trials at two sites (western and eastern Norway) at 60° North. The rootstocks included two selections of M.9 (EMLA, RN.29), two from the Polish (P) series (P.59, P.60), three from the Geneva (G) series (G.30, G.78730-026, G.202) and M.26. Trees were planted in the spring 1997 as two years old feather trees, spaced 1.5 x 4 m, trained as slender spindles and evaluated for five subsequent years. Soil management were grass in the alleyways and herbicide strips 1-m wide along the tree rows. Tree size was significantly affected by the rootstocks after five years growth. P.59, G.78730-026 and M.9 RN.29 produced the smallest and G.30 and G.202 the largest trees as measured by trunk cross-sectional area. P.59 and G.30 had the greatest yields per tree, followed by G.202, P.60 and M.9 EMLA. Trees on P.59 were the most yield efficient followed by the two M.9 clones. The fruit density measured as number of fruits per trunk-cross-sectional area showed similar results. The different rootstocks affected little the fruit weights. Fruit quality characterized by the content of soluble solids was in general high and did not differ between trees on the various rootstocks.
Forfattere
Mekjell MelandSammendrag
During the period 1998-2000, thinning trials were conducted using bloom thinners on mature European plum trees at Ullensvang Research Centre in western Norway. In 1998, unsprayed control and hand-thinned `Victoria" trees were compared with trees treated at full bloom with a single application of 1% Armothin® or 1.5% ammoniumthiosulphate (ATS). The same program was conducted in the following two years with the addition of a single full bloom treatment with 250 ppm ethephon and a post-bloom application one month after full bloom with the mixture 10 ppm 1-napththaleneacetic acid (NAA) and 75 ppm ethephon. Generally, thinning treatments reduced crop load and enhanced fruit quality (fruit size, soluble solid content, fruit firmness and ground and surface colour), but the results varied from year to year. Fruit set was reduced to about half of control values and the percentage of class 1 fruits was doubled compared to the control trees. All thinning compounds caused some minor leaf injury but no fruit damage. No differences in the amount of gummosis (internal disorder of the fruits) were observed due to treatments. Return bloom was improved by thinning.
Forfattere
Ann NorderhaugSammendrag
Det er ikke registrert sammendrag
Forfattere
Ann Norderhaug H. SickelSammendrag
Det er ikke registrert sammendrag
Forfattere
Ann NorderhaugSammendrag
Det er ikke registrert sammendrag
Forfattere
N. Sæther H. Sickel Ann Norderhaug O. VangenSammendrag
Det er ikke registrert sammendrag
Forfattere
R. Holme Ann NorderhaugSammendrag
Det er ikke registrert sammendrag
Forfattere
I. Austad Ann Norderhaug L. Hauge A. MoenSammendrag
Det er ikke registrert sammendrag
Forfattere
Ann Norderhaug Silke Hansen J.B. JordalSammendrag
Det er ikke registrert sammendrag