Pollen dispersal pattern from the mediterranean shrub Cistus ladanifer L. to its congener C. laurifolius L.: ecological and conservation implications

Gene flow between congeners in natural systems can have important consequences for the species involved. Cistus ladanifer plays a significant role in natural ecosystems and is also considered a valuable source of natural resources. The objective of this study is to investigate the pollen dispersal pattern from this species to its congener, Cistus laurifolius. To this end, an analysis of pollen analog dispersal (using fluorescent dye) was conducted in a mixed population of both species. The pollen dispersal pattern of C. ladanifer to C. laurifolius was estimated, and the relationship between the dispersal distance and the distance from the pollen analog source of C. ladanifer plants was investigated. The results showed the ability of C. ladanifer to pollinate C. laurifolius. Cistus laurifolius plants closer to the particle emission source provided by C. ladanifer individuals received a greater amount of pollen analogs (fluorescent dye) on their stigmas than those farther away. Most of the detected pollen analogs (80%) dispersed within 60 meters of the donor plants. The evidence of pollen transfer from C. ladanifer to C. laurifolius highlights the importance of studying pollen dispersal patterns in species that are potential candidates for exploitation and use as new crops. This is crucial to avoid impacts on populations of other wild congeners.