Agriculture Reference
In-Depth Information
Table
.
The effect of time of taking cuttings of 'M.
'
apple rootstock and of the propagation environment on the
percentage rooting
Percentage rooting
Dates (/)
RH -%RH - %
November
December
January
February
March
From Howard (). Reprinted by permission of John
Wiley & Sons Inc.
Table
.
Establishment of Quince cuttings related to season of direct field
planting or prior stimulation with basal heat
Collection date
Mid-Nov
Mid-Jan
Mid-Feb
Prior treatment for wks at
◦
C
Directly planted into field
From Howard (). Reprinted by permission of John Wiley & Sons Inc.
Strictly speaking, etiolation is the development of plant parts in the absence of
light, but horticulturalists use the term to include development under heavy
shade. Banding is localized light exclusion. Bands of black adhesive tape or
Velcro are applied both to etiolated shoots and to light-grown shoots in the
softwood stage to exclude light from the portion of a stem that will be used as
the cutting base. When applied to non-etiolated shoots it is said to blanch the
relevant part of these. Shading refers to reducing the light level under which
stock plants are grown.
These treatments 'precondition' apple and pear shoots to root when ap-
plied at a number of different stages of development. Covering 'M.
' apple
rootstock hedges with black polythene structures for a month from budburst
raised the proportion of subsequent summer cuttings rooting from
%to
%
(Harrison-Murray and Howard,
). Although total light exclusion during
the period of shading stock plants of 'M.
' in the field maximized the improve-
ment in rooting of their cuttings, compared with those from unshaded plants,
even reduction of light to
% of ambient had a substantial effect on both the
