Agriculture Reference
In-Depth Information
Asteraceae
Example:
Helianthus annuus
1. Moistening: Soak in water 18 hr.
2. Preparation after moistening:
a. Cut seed longitudinally completely through the midsection of the distal half.
b. Cut seed longitudinally the entire length through the midsection. Adjust the slope of the cut to
avoid cutting into the embryonic axis at the basal end while cutting full depth at the distal end.
c. Remove distal end of the seed, including the cotyledon tips or edges.
3. Staining time: 6-24 hr.
4. Preparation for evaluation: Expose the embryo by removal of seed coat and residual nutritive
tissue or by gently pressing it through the previously cut opening at the distal end.
5. Evaluation of viable seeds: Embryo completely stained except for a small area of the distal part of
radicle and distal 1/2 of cotyledons if supericial and distal 1/3 if extending deep through tissue.
Asteraceae
Helianthus annuus
(1)
(2)
(1)
(2)
Viable Seed
Non-Viable Seed
(1) Entire embryo evenly stained, and (2)
unstained areas in the cotyledons.
(1) Unstained radicle, and (2) half or more
of the cotyledons damaged or unstained.
