Agriculture Reference
In-Depth Information
Convolvulaceae
Example:
Ipomoea purpurea
1. Preconditioning: Remove hard-seededness by nicking, puncturing or cutting of seed coat in a
non-destructive location.
2. Moistening: Soak in water 18 hr.
3. Preparation after moistening:
a. Additional seed coat preparation is not usually necessary, except to accelerate the uptake of
water and/or the staining solution.
b. Cut seed longitudinally through the seed coat and into the nutritive tissue near the midsection,
including one-half of the circumference.
c. Remove distal end of the seed, including the cotyledon tips or edges.
4. Staining time: 18-24 hr.
5. Preparation for evaluation: Expose the embryo and the adjoining nutritive tissue by spreading the
cut surfaces suficiently to expose the desired tissue.
6. Evaluation of viable seeds: Embryo completely stained except for a very small area of the distal
part of radicle or 1/3 of total cotyledon area.
Convolvulaceae
Ipomoea purpurea
(2)
(1)
(2)
(1)
Viable Seed
Non-Viable Seed
(1) Entire embryo evenly stained, and (2)
slight unstained areas of radicle, hypocotyl
or cotyledons.
(1) Unstained radicle, and (2) more than
half of the cotyledons unstained.
