GROWTH AND PRODUCTIVITY OF APPLE TREES AND FRUIT QUALITY AT HARVEST AS AFFECTED BY ROOTSTOCKS

The experiments were carried out on ‘Jonagold’ trees on rootstocks of Polish selection: P2, P14, P22, P60 and Malling Series: M.26, M.9. The growth rate of trees on P14 was the most vigorous, on M.26 and P2 weaker, on M.9 and P60 intermediate and trees on P22 were the least vigorous.
Trees on P14 and P60 bore the highest cumulative yields whilst the cumulative yields for trees on M.9, M.26 and P2 were similar to each other.
The lowest cumulative yields were for trees on P22. Estimates of crop efficiency index (CEI) indicate that trees on M.9, P60 and P2 were very efficient but the most efficient ones were those on rootstock P22. On average, fruit size (expressed on a weight basis) of apples from trees on studied rootstocks were close to the optimal for consumption for ‘Jonagold’ (200-220 g). However, trees on M.9 tended to produce larger fruit and on P22 smaller ones.
There was no effect of rootstock on fruit blush area, but rootstocks affected fruit maturity.
Fruit from trees on rootstock M.9 reached harvest maturity usually 3-5 days earlier than on other rootstocks and tended to obtain the lowest values of Streif index.
The starch index was not influenced by rootstocks.
The flesh firmness reached the highest values for apples from trees on M.26 and P60. Rootstocks affected the content of carbohydrates and organic acids.
Soluble solids content was the highest for fruits from trees on P22 and P2, but the lowest on P14. Apples from the most vigorous trees, on P14 and M.26 respectively, had the highest acid content in the edible portion of flesh at harvest.

VIII International Symposium on Canopy, Rootstocks and Environmental Physiology in Orchard Systems

J. Skrzyński

Malus × domestica, yield, fruit size, flesh firmness, soluble solids, acids, Streif index

https://doi.org/10.17660/ActaHortic.2007.732.17