2. Materials and Methods
2.1. Gametophyte Study
2.2. Whole Seed Studies
- Fresh weight relations of seeds were determined by comparing gametophyte weight with whole seed weight. Seed age ranged from 3 to 30 months and included 394 seeds.
- Dry weight relations of seeds were determined by separating seeds into sarcotesta, sclerotesta and gametophyte tissue. The flotation tissue was included with the sclerotesta category. For older seeds, the embryo was included with the gametophyte category. Seed age ranged from 7 to 24 months and included 60 seeds. To provide a check on the influence of sequentially harvesting seeds of more than one age from the same trees, a population of eight trees were set aside to supply a single seed age.
- Seed equatorial dimension relationships were determined by cutting each seed in half then measuring the diameter of sarcotesta, sclerotesta, flotation tissue and gametophyte tissue. Total diameter of each category was determined by adding the diameters of each side. Seed age ranged from 4 to 28 months and included 210 seeds.
- Seed longitudinal dimension relationships were determined with the same seeds by measuring the diameter of sarcotesta, sclerotesta, flotation tissue and gametophyte. Seed age ranged from 4 to 28 months and included 210 seeds.
Conflicts of Interest
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