Agriculture Reference
In-Depth Information
'Malling
'
(
'M.
'
) was selected at East Malling in
. It is semi-dwarfing,
producing trees
% of the size of those on apple seedling rootstocks.
It is widely used in North America but by the mid-
-
s more trees were
planted on the more dwarfing rootstocks. 'M.
' induces precocious cropping
on a per tree basis but is unsuited to high-density plantings. It tolerates a wide
range of soil temperatures and is resistant to fire blight. It tends to form root
suckers.
'Malling
'
(
'M.
'
) was selected at East Malling in
, its parents being
'Northern Spy' and 'M.
. It gives
trees almost as vigorous as those on seedling rootstocks but they are much more
precocious and productive. Although it is not resistant to woolly apple aphid
it is used in South Africa on poor soils or where there is a 'replant' problem
which checks growth.
'Malling-Merton
', and was introduced into commerce in
'
(
'MM.
'
) was selected from crossing 'Northern Spy'
and 'M.
' between
and
and introduced in
. It is semi-dwarfing,
giving trees rather larger than those on 'M.
', and is outstanding for its effects
on precocity and fruitfulness. The trees do not need staking. It is widely used
in western Europe, especially in semi-intensive 'hedgerow' orchards, and in
New Zealand and South Africa where its resistance to woolly apple aphid
is important. Its susceptibility to
Phytophthora cactorum
limits its use in North
America and parts of Europe. It is very easy to propagate.
'Malling-Merton
'
(
'MM.
'
) originated at Merton, England from
'M.
'
×
'Northern Spy' parentage. It was selected in
and
and
introduced into commerce in
. Trees on it are as vigorous as those on
seedling rootstocks but it is resistant to woolly apple aphid and gives heavier
cropping. The trees are poorly anchored but it is still used in South Africa on
soils of low growth potential. It is easily propagated by stooling.
'Malling-Merton
'
(
'MM.
'
) was selected at Merton, England in
, its
parents being 'Northern Spy' and 'Merton
%ofthe
size of those on seedling rootstocks, but they are much more precocious and
productive than those on seedlings or on the older 'M.
'. It gives trees
-
' rootstock of similar
vigour. It is particularly tolerant of drought conditions and sandy soils (MAFF,
). It is resistant to woolly apple aphid and is still used in South Africa. It
is easily propagated.
'M.
'
(
'AR.
.
.
'
) was selected at East Malling from crosses made in
between 'MM.
' and 'M.
' and introduced in
. It gives trees similar in
size to, or appreciably smaller than, those on 'MM.
', has similar effects on
cropping efficiency and fruit size and is resistant to collar rot, mildew, woolly
apple aphid and the specific apple replant disease common in UK orchards.
It roots well from hardwood cuttings.
'Merton
'
(
'M.
'
) was selected from seedlings of the cross 'Northern
Spy'
×
'M.
'. It gives trees of similar size to those on 'MM.
' and is resistant
