Abstract

Tillandsia landbeckii Phil. is a rootless epiphyte that grows on dunes of the Atacama Desert. There is little information on its natural history, particularly concerning its reproductive ability. To better understand whether sexual reproduction can contribute to recruitment in T. landbeckii, we examined its basic reproductive traits and developed a germination protocol. We marked and censused plants, as well as collected seeds from four localities along an inland-coast gradient of the southernmost Tillandsia dune in Chile. Seeds were tested for viability and used for germination trials using four culture mediums. Plants vary in size, capsule size and number of seeds per capsule along the gradient, with larger plants occurring inland. Both the probability of flowering and of producing capsules increased with plant size. However, seed viability was low and did not differ across localities. Germination trials were successful, but also yielded relatively low germination probabilities. In summary, our results revealed plant size-related variation in T. landbeckii's reproductive capacity. In spite of this variation, however, low seed viability supports previous findings that sexual reproduction scarcely contributes to recruitment in this population; hence propagation of this species may eventually be necessary to promote genetic diversity.