Abstract
The coastal plant Pandanus odoratissimus L.f. is distributed from the tropics to the subtropics. We studied this species to clarify the differences in its population dynamics and growth strategies between populations at a tropical plot at Cipatujah, West Java, Indonesia (7°46´S, 108°04´E) and at subtropical plot at Tokuno-shima Island, Japan (27°53´N, 128°57´E). We measured plant morphological characteristics and estimated plant growth from stem elongation during a one year period. We analysed genetic differentiation using five inter-simple sequence repeat (ISSR) primers. Based on a sample of 60 individuals, we found 87 polymorphic ISSR loci in the tropical plot, versus 76 in the subtropical plot, suggesting higher genetic diversity in the tropical plot. The plants in the tropical plot had a taller, less-branched stem and larger leaves. The average stem elongation was 18 cm yr-1 in the tropical plot and 7 cm yr-1 in the subtropical plot. This difference probably caused the difference in maximum plant height between the tropical plot (9 m) and the subtropical plot (4.6 m). The stem diameters were similar in the two populations. The fruits were bigger in the tropical plot. Climate differences strongly affected plant height and fruit size, but had little effect on stem diameter.