The rationale for this study was to characterize the dormancy factors that contribute to slow germination and poor stand performance in Pensacola bahiagrass (Paspalum notatum Flugge). Several dormancy releasing treatments were ineffective. The importance of the lemma was established by excising parts of the seed covers. Removing the second glume and sterile lemma did not reduce dormancy. Removing the palea resulted in significantly improved germination but still not as rapid nor as complete as removing the lemma. Germination was observed to occur by the coleorhiza protruding through an opening in the lemma caused by the separation of fibers immediately above the embryo. Aging the seed increased germination and the number of seed with visible, separated fibers. A dormancy mechanism is proposed in which water uptake and the expansion of the embryo are restricted until an opening occurs in the lemma.

A broad source of Gerbera × hybrida Hort. germplasm was evaluated for vase life. Senescence mode, i.e., bending or folding of stems or wilting of ligulae was also recorded for flowers evaluated. Intensive selection was practiced to improve vase life. About 10% of the plants from a sample population were selected for having flowers with high vase life. Progeny means for vase life resulting from a topcross between these plants and `Appleblossom' were used to select five plants (about 1.5% of the sample population) whose flowers had high vase life. A diallel cross using these five plants as parents resulted in a progeny population with an increase in mean vase life of 3.4 days compared to mean vase life for the initial sample population. Increases in vase life means for days to bending, folding, and wilting were 0.3, 3.5, and 1.2 days, respectively. Plants with flowers which senesced due to wilting had the longest mean vase life before and after breeding. Changes in proportion of senescence modes were observed; bending decreased, folding and wilting increased. Frequencies of bending, folding, and wilting were compared to vase life means for 10 progenies. Proportion of bending generally decreased as vase life increased.

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Callus cultures were initiated from mature excised caryopses of bahiagrass (Paspalum notatum Flugge) on Murashige & Skoog medium supplemented with 20 gl-1 sucrose and 2 mg 1-~ 2,4-D. Excised mature caryopses readily germinated and callus developed at the base of coleoptiles. There was considerable variation in the amount of non-embryogenic callus among the cultures. Most of the explants produced non-embryogenic translucent callus consisting of thin-walled cells and unorganized tissue. Some of these calli gave rise only to roots. Other explants formed embryogenic calli which were distinguished morphologically as white, globular and friable. Somatic embryos developed and germinated precociously when embryogenic caUi were transferred to a 2,4-D-free medium. Somatic embryogenesis was confirmed by histological sections and scanning electron microscopy. Of the 300 cultures, 35 were embryogenic but only 10 produced plants that were successfully grown to maturity.