In respect to the great questions of heredity, the stocks offer many
points of interest. Some of these features I will now try to describe,
in order to show what still remains to be done, and in what manner the
stocks may clear the way for the study of the ever-sporting varieties.
The first point, is the question, which seeds become double-flowered and
which single-flowered plants? Beyond all doubt, the determination has
taken place before the ripening of the seed. But though the color of the
seed is often indicative of the color of the flowers, as in some red or
purple varieties, and though in balsams and some other instances the
most "highly doubled" flowers are to be obtained from the biggest and
plumpest seeds, no such rule seems to exist respecting the double
stocks. Now if one half of the seeds gives doubles, and [335] the other
half singles, the question arises, where are the singles and the doubles
to be found on the parent-plant?
The answer is partly given by the following experiment. Starting from
the general rule of the great influence of nutrition on variability, it
may be assumed that those seeds will give most doubles, that are best
fed. Now it is manifest that the stem and larger branches are, in a
better condition than the smaller twigs, and that likewise the first
fruits have better chances than the ones formed later. Even in the same
pod the uppermost seeds will be in a comparatively disadvantageous
position. This conception leads to an experiment which is the basis of a
practical method much used in France in order to get a higher percentage
of seeds of double-flowering plants.
This method consists in cutting off, in the first place the upper parts
of all the larger spikes, in the second place, the upper third part of
each pod, and lastly all the small and weak twigs. In doing so the
percentage is claimed to go up to 67-70%, and in some instances even
higher. This operation is to be performed as soon as the required number
of flowers have ceased blossoming. All the nutrient materials, destined
for the seeds, are now forced to flow into these relatively few embryos,
and it is clear that [336] they will be far better nourished than if no
operation were made.
In order to control this experiment some breeders have made the
operation on the fruits when ripe, instead of on the young pods, and
have saved the seeds from the upper parts separately. This seed,
produced in abundance, was found to be very poor in double flowers,
containing only some 20-30%. On the contrary the percentage of doubles
in the seed of the lower parts was somewhat augmented, and the average
of both would have given the normal proportion of 50%.
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Elsewhere in the archive
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account