P-22 was developed by Dr. S. W. Zagaja at Skierniewice, Poland and is a cross between M-9 x Common Antonovka.
Influence on Scion Habit
Trees on P-22 rootstock are less vigorous then trees on M-9 but are comparable to MARK rootstock in size.
P-22 is resistant to collar rot, perennial canker, European canker and silver leaf. This rootstock has shown a high level of resistance to apple scab, powdery mildew and crown gall. P-22 is as susceptible to fire blight as M-9 and is also not resistant to woolly apple aphids.
P-22 roots well in the layer bed and resembles M-9 in growth with numerous lateral branches being produced. It defoliates medium to late, like M-9 and breaks bud late in the spring also. P-22 shows no burrknot tendency.
P-22 has exceptional winter hardiness that is comparable to Alnarp 2 and when used as an interstem which will produce trees that are MARK size. P-22 induces early fruiting and has a cropping efficiency like that of M-9. P-22 is better anchored than M-9 and is not as brittle in rooting.