LANKESTERIANA


FIGURE 2. Development of capsules of P. humboldtii (A, A'), P. longifolium (B B1) and P. pearcei (C C1) at pollination
 day (left) and one week before capsule opening (right).


In vitro germination. In order to consider only the viable
seeds when calculating germination rate, percentage of
seeds that germinated in the culture medium was corrected
with the rate of viable seed measured for each capsule,
as described in Materials and Methods. The corrected

LANKESTERIANA8(2), August 2008. 0 Umversidad de Costa Rica, 2008.


percentage of germination was lower in P humboldtii
(2.9%) than in P pearcei (38.7%) and P longifolium
(41.3%), without significant differences between the last
two (Fig. 3). Developing protocorms that subsequently
died were observed only in P pearcei (Fig. 3).