GROWTH AND YIELDING OF APPLE CULTIVARS ON THE ROOTSTOCK M 26 IN LATVIA

M 26 is one of the most used rootstocks in the temperate climate zone.
However, there is no clear information about the interaction between this and the commercially cultivars grown in Latvia.
Two trials were established in spring of 1998 at the Latvia State Institute of Fruit-Growing (Dobele) in the southern part of Latvia.
Four apple cultivars of different origin – ‘Auksis’ (originated in Lithuania), ‘Zarya Alatau’ (Kazahstan), ‘Lobo’ (Canada) and ‘Sinap Orlovskii’ (Russia) – were planted as one year old trees on rootstock M 26 in Dobele.
Trees were planted at 1.5×4 m, with three replications in a leached sod-calcareous soil with pH 7.4, 1.9% organic matter, where plant available K₂O and P₂O₅ were 149 mg•kg^-1 and 113 mg•kg^-1, respectively.
A second trial with two year old branched trees was planted in gleyic sod-calcareous soil, with pH 6.6, organic matter 2.3%, P₂O₅ 241 mg•kg^-1 and K₂O 267 mg•kg^-1. Dwarf rootstocks B 9, B 396, M 26 EMLA, and semi-dwarf rootstocks MM 106, G.30 and others were compared.
The planting distances were 4×2 m for dwarf rootstocks and 5×3 m for semi-dwarf rootstocks.
The trees on dwarf rootstocks were trained in a slender spindle system, and as free standing central leader trees on semi-dwarf rootstocks.
No visible incompatibility was found between rootstock M 26 and the four investigated cultivars.
Cultivars ‘Auksis’, ‘Zarya Alatau’ and ‘Sinap Orlovskii’ showed good yield and growth on this rootstock.
Differences between cultivars in bienniality were significant statistically.
Smaller bienniality was shown for the less productive cultivar ‘Lobo’ and also for the productive one ‘Sinap Orlovskii’. In the second trial trunk cross-section area of ‘Ausksis’ for trees on M 26 EMLA was higher than for trees on B 9 and B 396, little larger than trees on G.30 and smaller than trees on MM 106. Total yield of apples on M 26 EMLA was higher than on both B series rootstocks, but lower than on MM 106 and G.30. Yield efficiency of trees on rootstock M 26 EMLA was less than trees on B 9, B 396 and G.30, but close to trees on MM 106. Fertile soil and good quality plant material promoted high growth and productivity of the apple cultivar ‘Auksis’, but delayed bearing and increased biennial bearing.

XXVIII International Horticultural Congress on Science and Horticulture for People (IHC2010): International Symposium on the Challenge for a Sustainable Production, Protection and Consumption of Mediterranean Fruits and Nuts

E. Rubauskis, M. Skrivele, L. Ikase

Malus, yield efficiency, biennial yielding, canopy volume, branching

https://doi.org/10.17660/ActaHortic.2012.940.73