Rootstocks serve to increase productivity and improve efficiency through improved tree survival, restrict tree vigor, and increase fruit size, yield and quality. Preliminary research conducted in other areas and by the NC-140 USDA technical committee (www.nc140.org) suggests that there are several new rootstocks with attributes suitable for the Ontario tender fruit industry. Krymsk 86 is a new rootstock that is tolerant of cold temperatures, drought, excessive moisture, resistant to phytophthora, and somewhat resistant to lesion nematodes.

The objective of this research was to propagate and establish small research blocks of 'Redhaven' peach and 'Fantasia' nectarine trees on 'Krysmk 86' and 'Bailey' rootstocks to determine their suitability for Ontario's tender fruit industry.

Materials and Methods

Research plots of 'Fantasia' trees were established at two commercial orchards in Niagara-on-the-Lake (NOTL) and Beamsville, Ontario. Twenty-five trees each of 'Fantasia'/'Krymsk 86' and 'Fantasia'/'Bailey' were planted in a randomized complete block design with five trees per experimental unit. Treatments were replicated five times. Trees were planted at a spacing of ~1.5 m X 4.0 m (1666 trees/ha, 675 trees/acre) and trees were trained to a central leader system using wire trellis.

'Redhaven' trees on the same rootstocks will be planted in 2014 at the University of Guelph, Horticultural Experiment Station, Simcoe.

Initial data was collected in 2013 on tree growth (trunk circumference; tree height, tree spread, number of rootstock suckers, tree morality). If additional funding is received, additional data on fruit (total yield, total number of fruit, mean fruit size, crop load, yield efficiency) characteristics and growth with be collected once the trees begin to fruit in 2015.

Results & Discussion

'Fantasia' trees on 'Krymsk 86' had greater trunk diameters at planting at both locations. This may be more a function of propagation method than rootstock genetics as the 'Krymsk 86' rootstock were derived from tissue culture whereas the 'Bailey' trees were derived from seedlings. Trees on 'Krymsk 86' at Niagara-on-the-Lake (NOTL) were significantly taller and had slightly more branches per tree as well (Table 1).

Table 1. Vigor of 'Fantasia' nectarine trees on 'Krymsk 86' and 'Bailey' rootstock, as indicated by trunk diameter, tree height, number of branches and tree mortality planted in 2013
Niagara-on-the-Lake
At planting (Spring 2013)
RootstockTrunk diameter (cm)Tree height (cm)Number of branches/tree
Krymsk 86
1.6
101.9
5
Bailey
1.5
95.0
4
Significancey
***
**
***
P value
0.0001
0.0083
<0.0001

Beamsville
At planting (Spring 2013)
RootstockTrunk diameter (cm)Tree height (cm)Number of branches/tree
Krymsk 86
1.7
113.9
7
Bailey
1.6
112.4
7
Significancey
*
ns
ns
P value
0.0255
0.1106
0.4263

 

Niagara-on-the-Lake
Fall 2013
RootstockTree mortality (%)Trunk diameter (cm)Tree height (cm)Number of branches/treeIncrease in diameter growth Spring-Fall (cm)
Krymsk 86
2
2.27
145.6
8.0
0.70
Bailey
4
1.94
125.2
7.1
0.48
Significancey
ns
***
***
*
***
P value
0.5515
<0.0001
<0.0001
0.0423
<0.0001

 

 

Beamsville
Fall 2013
RootstockTree mortality (%)Trunk diameter (cm)Tree height (cm)Number of branches/treeIncrease in diameter growth Spring-Fall (cm)
Krymsk 86
8
1.81
141.0
9.9
0.19
Bailey
14
1.76
138.6
9.3
0.18
Significancey
*
**
ns
ns
ns
P value
0.0172
0.0028
0.0684
0.0606
0.8660

 

z average values with the same letter within a given column are not significantly different according to Duncan's multiple range test at P=0.05.
y ns, ***, **, *, indicates non significance and statistical significance at P=0.001, P=0.01, and P=0.05, respectively

At the end of the 2013 growing season, trees on 'Krymsk 86' grew significantly greater than trees on 'Bailey' at the NOTL orchard, had more branches per tree, were taller and had greater trunk diameters in comparison with trees on 'Bailey' rootstock.

Overall, seasonal growth at the Beamsville location was less than NOTL and differences between rootstocks were minimal. Moreover, tree mortality on 'Bailey' rootstock was 14% in comparison with 8% on 'Krymsk 86'. This greater loss was likely more site specific than related to rootstock differences as many of the tree losses occurred in localized locations in the orchard. Tree diameters, height, and branches per tree were all similar between rootstocks at the Beamsville site.

As this is the first year of growth and trees are in their establishment phase, these data must be considered very preliminary. Overall, trees grew greater at the NOTL location than Beamsville. 'Krymsk 86' appears more vigorous in the first leaf than 'Bailey', however this may be related to greater initial root mass of 'Krysmk 86' trees at the time of planting compared to the 'Bailey' trees (data not shown). Root size and quality may have contributed to the greater growth observed in the 'Krymsk 86' trees. Once the tree have established and overcome any transplant shock, the importance of initial growth parameters at the time of planting will become less important and vigor and production should more closely reflect genetic differences in the plant material.

Acknowledgements :

We gratefully acknowledge Mori Nurseries for providing trees, Mr. Tony Sgambelluri, Mr. T and V. Pilliteri, for providing the use of their orchards. We also acknowledge the technical assistance of Mr. Ken Slingerland. We also would like to thank the Niagara Peninsula Fruit and Vegetable Growers' Association the University of Guelph and OMAF/MRA for their financial support of this research.