Mekjell Meland - Academia.edu (original) (raw)

Papers by Mekjell Meland

Elstar' is the latest-maturing commercial apple cultivar grown in Norway, with high fruit quality... more Elstar' is the latest-maturing commercial apple cultivar grown in Norway, with high fruit quality when properly managed. In May 2006, an experiment with four different crop loads [2, 4 ,6, or 8 flowers or fruitlets cm -2 trunk crosssectional area (TCSA), respectively] was established at two different stages [first bloom (FB), or 20-mm diameter fruitlets] and compared to unthinned control trees. Fruit growth was measured on individual fruit for each treatment throughout the season at weekly intervals. Thinning at FB gave a significantly lower final percentage fruit set than thinning to the same cropping level at the 20-mm fruitlet stage. However, fruit weights and soluble solids contents (SSC) were significantly higher, and the background fruit colour improved when trees were thinned at FB. The final number of fruit at harvest was less than the amount established at FB, or at the 20-mm fruitlet stage. There were significant differences between treatments in final fruit numbers per TCSA, which reflected the different crop loads. Fruit weights and SSC values were highest with the lowest crop load, and decreased with increasing crop loads. There was also a strong crop-load effect on the extent of return bloom per tree in the subsequent year. Trees thinned at FB had significantly more flower clusters than those thinned at the 20-mm fruitlet stage of. Untreated control trees had the lowest number of flower clusters. The amount of return bloom declined with increasing crop load. Second year crop loads and fruit weights were highest when trees were thinned at FB to two or four apples cm -2 TCSA in the previous year. Trees with the highest crop load had the lowest crop load in the following year. Fruit quality was generally high for all treatments.

Acta Agriculturae Scandinavica, Section B - Plant Soil Science, 2010

The performances of the plum rootstocks Marianna GF 8-1, Pixy, and Wangenheim, compared with St. ... more The performances of the plum rootstocks Marianna GF 8-1, Pixy, and Wangenheim, compared with St. Julien A as a standard, for the cultivars 'Avalon', 'Edda', 'Excalibur', 'Jubileum', 'Reeves', and 'Victoria' were assessed in a field trial in western Norway at 608 North. Trees were planted in spring 1999; the plant material was one-year-old whips, spaced 2.0 )4.5 m and formed with a central leader as free spindles. Tree vigour, yield, fruit size, fruit quality, and yield efficiency were evaluated for the seven subsequent years. Tree size was significantly affected by the rootstocks after seven years' growth. Wangenheim produced the smallest and St. Julien A and Pixy the largest trees as measured by trunk cross-sectional area, on average for the different cultivars. However, Pixy produced significant larger yields per tree for the cultivar 'Reeves' than did St. Julien A. 'Edda' gave the smallest yield and 'Avalon the largest. Trees on Pixy were the most yield efficient for all cultivars with the exception of 'Victoria'. The fruit sizes became little affected by the different rootstocks. 'Edda' and 'Victoria' produced the smallest fruits and 'Excalibur' and 'Reeves' the largest. Fruit quality characterized by the content of soluble solids was on average 16.1% and did not differ between trees on the various rootstocks. The cultivar 'Avalon' had the highest contents of soluble solids and 'Reeves' the lowest. The nutrient levels in the leaves were within the optimum range by the end of the seventh season. Trees on Marianna GF 8-1 had the highest nitrogen and magnesium leaf uptake. In conclusion, St. Julien A and Pixy were the most reliable semi-vigorous rootstocks which induced high yield efficiency and with favourable influences on fruit quality to the six European plum cultivars. Pixy is a good alternative to St. Julien A, with a lower vigour in trees, more precocity, and higher yield efficiency.

Acta Agriculturae Scandinavica, Section B - Soil & Plant Science, 2005

... Please follow the link if you wish to visit the database now. Acta Agriculturae Scandinavica,... more ... Please follow the link if you wish to visit the database now. Acta Agriculturae Scandinavica, Section B - Soil & Plant Science. ... View all references) conducted research on pruning of 'Victoria' plums. Christensen (197322. Vittrup Christensen, J. (1973). A pruning trial with plums. ...

Acta Agriculturae Scandinavica, Section B - Plant Soil Science, 2007

ABSTRACT

There is a need for classifying and conserving local apple cultivars from two main regions in Bos... more There is a need for classifying and conserving local apple cultivars from two main regions in Bosnia and Herzegovina (B&H). Consequently, 71 local apple accessions (31 from Sarajevo and 40 from eastern Bosnia) were evaluated with a set of 10 simple sequence repeats (SSRs). These accessions were compared with 37 reference cultivars (24 traditional B&H and 13 international cultivars maintained at the ex situ collection Srebrenik) to determine synonyms, homonyms, and possible introgression of foreign genotypes into the local apple germplasm. Using 10 primer pairs of microsatellites, we were able to amplify 135 alleles for the 71 local apple accessions. Detection of more than two different alleles per locus was observed for 34 accessions. Fourteen different homonyms and 12 synonyms were identified among all the apple cultivars analyzed. Analysis of molecular variance (AMOVA) revealed a significant genetic differentiation between most of the groups analyzed but not between accessions fro...

In the cherry rootstock trials at Ullensvang, Norway the following quality prameters of sweet che... more In the cherry rootstock trials at Ullensvang, Norway the following quality prameters of sweet cherry cultivars: Van, Ulster and Burlat on seedling, Colt and Gisela 5 were evaluated: mean fruit weight, content of soluble solids, acidity, flesh firmness and percentage of fruit in individual size classes. The above quality parameters fluctuated markedly during the experimental summer period of 1998. Individual cultivars responded in various ways to the kind of rootstock. The kind of rootstock exerted a significant influence on the individual factors determining fruit quality. It significantly influenced fruit external features, i.e., their size and percentage of stone in total fruit weight. The largest fruit of cv. Van noticed on seedling rootstock, cv. Ulster on Colt and cv. Burlat on Gisela 5. However the largest stone-weight per total fruit-weight in all cultivars studied was in fruits from trees on Gisela 5. The fruits of all cultivars reacted with different firmness depending on t...

…, 2003

Three different rain protective covering methods for sweet cherry (Prunus avium) trees were teste... more Three different rain protective covering methods for sweet cherry (Prunus avium) trees were tested with uncovered trees as control. The covers were a pitched cover mounted permanently, a similar cover mounted only when raining, and a permanent umbrella type enveloping the top and sides of single trees. Covers were mounted 3 weeks before and throughout the harvest period in two seasons with different weather conditions. All three covering methods increased the amount of marketable fruit from 54% on uncovered to 89% on covered trees in mean of 2 years. Fruit from umbrella covered trees had lower soluble solid content, lower juice color and lower ripeness compared with fruit from all other trees, reflecting the different microclimate in these trees such as frequently higher maximum temperatures and greater vapor pressure. The two pitched covers produced no significant changes in microclimate or internal fruit quality compared with uncovered trees.

Crop Protection, 2007

The aim of this three-year study (2001)(2002)(2003) was to optimize fungicide application against... more The aim of this three-year study (2001)(2002)(2003) was to optimize fungicide application against anthracnose (Colletotrichum acutatum) in sweet and sour cherry orchards. The experimental sprays were applied to trees receiving normal fungicide programmes (grower schedule), although without the use of dithianon, except for the first year where only the experimental applications were applied to the sour cherry trees. Fungicide treatments were applied with either dithianon or copperoxychloride added prior to flowering or with dithianon added after flowering. Spraying with dithianon or copperoxychloride prior to flowering did not significantly reduce anthracnose compared to untreated. Two applications with dithianon during the green fruit stage (from petal fall and during the following 3-4 weeks) greatly reduced anthracnose at harvest. Three applications on green fruit did not reduce disease more than two applications. In sweet cherries, two sprays with dithianon at the green fruit stage in addition to the grower schedule reduced anthracnose at harvest from 14% to 3% in 2002 and from 15% to 1% the following year. In 2001, when very few fruit developed anthracnose, no treatment effects were evident. Treatments on green sour cherry fruit similar to those on sweet cherries reduced the attack of anthracnose from 85% to 42% in 2002 and from 51% to 12% the following year. In 2001, no treatment included only sprays on green fruit. However, one treatment, which included copperoxychloride at bud burst, one application of dithianon during flowering and two applications on green fruits, reduced anthracnose from 27% to 9%. Based on these results, cherry growers are recommended to spray twice with dithianon on green fruit if they have a history of anthracnose in their orchards.

Acta Agriculturae Scandinavica, Section B - Plant Soil Science, 1995

... Best-fit regression equations approxi-mated a linear model. There was no difference in water ... more ... Best-fit regression equations approxi-mated a linear model. There was no difference in water accumulation and cracking severity at 25°C between “Sam” and “Ul-ster” fruit for either Colt or F.12/1 rootstocks (Figs. 2b and 2d). Cracking severity (Figs. ...

Acta Agriculturae Scandinavica, Section B - Plant Soil Science, 1995

Page 1. Acfa Agric. Scand. Srct. B, Soil and Planf Sci. 1995: 45, 223-230 Printed in Ireland. All... more Page 1. Acfa Agric. Scand. Srct. B, Soil and Planf Sci. 1995: 45, 223-230 Printed in Ireland. All righfs rrsrrwd Fruits from covered trees were associated with a 10% increase in weight. This paper will discuss the implications of ...

Elstar' is the latest-maturing commercial apple cultivar grown in Norway, with high fruit quality... more Elstar' is the latest-maturing commercial apple cultivar grown in Norway, with high fruit quality when properly managed. In May 2006, an experiment with four different crop loads [2, 4 ,6, or 8 flowers or fruitlets cm -2 trunk crosssectional area (TCSA), respectively] was established at two different stages [first bloom (FB), or 20-mm diameter fruitlets] and compared to unthinned control trees. Fruit growth was measured on individual fruit for each treatment throughout the season at weekly intervals. Thinning at FB gave a significantly lower final percentage fruit set than thinning to the same cropping level at the 20-mm fruitlet stage. However, fruit weights and soluble solids contents (SSC) were significantly higher, and the background fruit colour improved when trees were thinned at FB. The final number of fruit at harvest was less than the amount established at FB, or at the 20-mm fruitlet stage. There were significant differences between treatments in final fruit numbers per TCSA, which reflected the different crop loads. Fruit weights and SSC values were highest with the lowest crop load, and decreased with increasing crop loads. There was also a strong crop-load effect on the extent of return bloom per tree in the subsequent year. Trees thinned at FB had significantly more flower clusters than those thinned at the 20-mm fruitlet stage of. Untreated control trees had the lowest number of flower clusters. The amount of return bloom declined with increasing crop load. Second year crop loads and fruit weights were highest when trees were thinned at FB to two or four apples cm -2 TCSA in the previous year. Trees with the highest crop load had the lowest crop load in the following year. Fruit quality was generally high for all treatments.

Acta Agriculturae Scandinavica, Section B - Plant Soil Science, 2010

The performances of the plum rootstocks Marianna GF 8-1, Pixy, and Wangenheim, compared with St. ... more The performances of the plum rootstocks Marianna GF 8-1, Pixy, and Wangenheim, compared with St. Julien A as a standard, for the cultivars 'Avalon', 'Edda', 'Excalibur', 'Jubileum', 'Reeves', and 'Victoria' were assessed in a field trial in western Norway at 608 North. Trees were planted in spring 1999; the plant material was one-year-old whips, spaced 2.0 )4.5 m and formed with a central leader as free spindles. Tree vigour, yield, fruit size, fruit quality, and yield efficiency were evaluated for the seven subsequent years. Tree size was significantly affected by the rootstocks after seven years' growth. Wangenheim produced the smallest and St. Julien A and Pixy the largest trees as measured by trunk cross-sectional area, on average for the different cultivars. However, Pixy produced significant larger yields per tree for the cultivar 'Reeves' than did St. Julien A. 'Edda' gave the smallest yield and 'Avalon the largest. Trees on Pixy were the most yield efficient for all cultivars with the exception of 'Victoria'. The fruit sizes became little affected by the different rootstocks. 'Edda' and 'Victoria' produced the smallest fruits and 'Excalibur' and 'Reeves' the largest. Fruit quality characterized by the content of soluble solids was on average 16.1% and did not differ between trees on the various rootstocks. The cultivar 'Avalon' had the highest contents of soluble solids and 'Reeves' the lowest. The nutrient levels in the leaves were within the optimum range by the end of the seventh season. Trees on Marianna GF 8-1 had the highest nitrogen and magnesium leaf uptake. In conclusion, St. Julien A and Pixy were the most reliable semi-vigorous rootstocks which induced high yield efficiency and with favourable influences on fruit quality to the six European plum cultivars. Pixy is a good alternative to St. Julien A, with a lower vigour in trees, more precocity, and higher yield efficiency.

Acta Agriculturae Scandinavica, Section B - Soil & Plant Science, 2005

... Please follow the link if you wish to visit the database now. Acta Agriculturae Scandinavica,... more ... Please follow the link if you wish to visit the database now. Acta Agriculturae Scandinavica, Section B - Soil & Plant Science. ... View all references) conducted research on pruning of 'Victoria' plums. Christensen (197322. Vittrup Christensen, J. (1973). A pruning trial with plums. ...

Acta Agriculturae Scandinavica, Section B - Plant Soil Science, 2007

ABSTRACT

There is a need for classifying and conserving local apple cultivars from two main regions in Bos... more There is a need for classifying and conserving local apple cultivars from two main regions in Bosnia and Herzegovina (B&H). Consequently, 71 local apple accessions (31 from Sarajevo and 40 from eastern Bosnia) were evaluated with a set of 10 simple sequence repeats (SSRs). These accessions were compared with 37 reference cultivars (24 traditional B&H and 13 international cultivars maintained at the ex situ collection Srebrenik) to determine synonyms, homonyms, and possible introgression of foreign genotypes into the local apple germplasm. Using 10 primer pairs of microsatellites, we were able to amplify 135 alleles for the 71 local apple accessions. Detection of more than two different alleles per locus was observed for 34 accessions. Fourteen different homonyms and 12 synonyms were identified among all the apple cultivars analyzed. Analysis of molecular variance (AMOVA) revealed a significant genetic differentiation between most of the groups analyzed but not between accessions fro...

In the cherry rootstock trials at Ullensvang, Norway the following quality prameters of sweet che... more In the cherry rootstock trials at Ullensvang, Norway the following quality prameters of sweet cherry cultivars: Van, Ulster and Burlat on seedling, Colt and Gisela 5 were evaluated: mean fruit weight, content of soluble solids, acidity, flesh firmness and percentage of fruit in individual size classes. The above quality parameters fluctuated markedly during the experimental summer period of 1998. Individual cultivars responded in various ways to the kind of rootstock. The kind of rootstock exerted a significant influence on the individual factors determining fruit quality. It significantly influenced fruit external features, i.e., their size and percentage of stone in total fruit weight. The largest fruit of cv. Van noticed on seedling rootstock, cv. Ulster on Colt and cv. Burlat on Gisela 5. However the largest stone-weight per total fruit-weight in all cultivars studied was in fruits from trees on Gisela 5. The fruits of all cultivars reacted with different firmness depending on t...

…, 2003

Three different rain protective covering methods for sweet cherry (Prunus avium) trees were teste... more Three different rain protective covering methods for sweet cherry (Prunus avium) trees were tested with uncovered trees as control. The covers were a pitched cover mounted permanently, a similar cover mounted only when raining, and a permanent umbrella type enveloping the top and sides of single trees. Covers were mounted 3 weeks before and throughout the harvest period in two seasons with different weather conditions. All three covering methods increased the amount of marketable fruit from 54% on uncovered to 89% on covered trees in mean of 2 years. Fruit from umbrella covered trees had lower soluble solid content, lower juice color and lower ripeness compared with fruit from all other trees, reflecting the different microclimate in these trees such as frequently higher maximum temperatures and greater vapor pressure. The two pitched covers produced no significant changes in microclimate or internal fruit quality compared with uncovered trees.

Crop Protection, 2007

The aim of this three-year study (2001)(2002)(2003) was to optimize fungicide application against... more The aim of this three-year study (2001)(2002)(2003) was to optimize fungicide application against anthracnose (Colletotrichum acutatum) in sweet and sour cherry orchards. The experimental sprays were applied to trees receiving normal fungicide programmes (grower schedule), although without the use of dithianon, except for the first year where only the experimental applications were applied to the sour cherry trees. Fungicide treatments were applied with either dithianon or copperoxychloride added prior to flowering or with dithianon added after flowering. Spraying with dithianon or copperoxychloride prior to flowering did not significantly reduce anthracnose compared to untreated. Two applications with dithianon during the green fruit stage (from petal fall and during the following 3-4 weeks) greatly reduced anthracnose at harvest. Three applications on green fruit did not reduce disease more than two applications. In sweet cherries, two sprays with dithianon at the green fruit stage in addition to the grower schedule reduced anthracnose at harvest from 14% to 3% in 2002 and from 15% to 1% the following year. In 2001, when very few fruit developed anthracnose, no treatment effects were evident. Treatments on green sour cherry fruit similar to those on sweet cherries reduced the attack of anthracnose from 85% to 42% in 2002 and from 51% to 12% the following year. In 2001, no treatment included only sprays on green fruit. However, one treatment, which included copperoxychloride at bud burst, one application of dithianon during flowering and two applications on green fruits, reduced anthracnose from 27% to 9%. Based on these results, cherry growers are recommended to spray twice with dithianon on green fruit if they have a history of anthracnose in their orchards.

Acta Agriculturae Scandinavica, Section B - Plant Soil Science, 1995

... Best-fit regression equations approxi-mated a linear model. There was no difference in water ... more ... Best-fit regression equations approxi-mated a linear model. There was no difference in water accumulation and cracking severity at 25°C between “Sam” and “Ul-ster” fruit for either Colt or F.12/1 rootstocks (Figs. 2b and 2d). Cracking severity (Figs. ...

Acta Agriculturae Scandinavica, Section B - Plant Soil Science, 1995

Page 1. Acfa Agric. Scand. Srct. B, Soil and Planf Sci. 1995: 45, 223-230 Printed in Ireland. All... more Page 1. Acfa Agric. Scand. Srct. B, Soil and Planf Sci. 1995: 45, 223-230 Printed in Ireland. All righfs rrsrrwd Fruits from covered trees were associated with a 10% increase in weight. This paper will discuss the implications of ...