Articles
PRELIMINARY RESULTS OF TRIALS WITH DWARFING APPLE AND PEAR ROOTSTOCKS
P.16, P.22, J.9 and B.146. Four rootstocks turned out to be in between M.9 and M.26, viz.
B.9, B.469, 0.3, and MAC 9. More trials are needed to confirm these results, because the differences in vigour were not significant in all cases.
All 8 roostocks equalled the standards in their effect on fruiting capacity and fruit quality.
However, B.146 showed many burr knots and P.16 gave a lot of root suckers.
Other rootstocks appeared less interesting because these equalled (P.1) or surpassed (B.118, B.490) M.26 in vigour.
Moreover, P.1 showed many burr knots and B.118 and B.490 gave less productive trees.
Another series of trials with apple showed that virus free M.9 subclones may differ in vigour.
For example, trees on subclone Fleuren 56 were less vigorous than on the standard T.337, whereas R. Nicolai 29 (in some trials) and Cepiland induced more vigour.
A trial with dwarfing rootstocks for pear showed that here, too, a range in vigour control exists.
BP-1 and Sydo gave a vigour similar to that of Quince A, whereas BA 29 gave more vigour.
The Caucasian quince C.132 induced less vigour than Quince C, but the unknown virus status of the former may have been involved.
So far, trees on Quince C were the most precocious in cropping.
In another trial it appeared that clones of Quince C and Quince Adams differ in their effects on growth.
Virus free Quince Adams equalled virus free Quince C in vigour and precocity of cropping.