| BACKGROUND: Many barrel or columnar cacti, including some in the Atacama Desert, produce their reproductive tissue at or near the terminal apices of solitary or minimally branched stems that lean toward the equator, reportedly to maximize exposure to photosynthetically active radiation (PAR). Those with lateral reproductive tissue, often produce the tissue on the equatorial side of the stems. An examination of the multi-stemmed, arbuscular cactus, Eulychnia breviflora, was made to determine if it follows the same general strategy. METHODS: Individuals of the species were evaluated along a 100 km transect in the Atacama Desert. The position of all floral buds and open flowers was documented relative to the center of the plants and relative to the center of... |
