XVI International Botanical Congess

Bursera medranoana (Burseraceae) is a species of hybrid origin between Bursera morelensis and Bursera schlechtendalii. B. medranoana lives in the state of Hidalgo, Mexico, where its population is as big as the one of B. morelensis, and much higher than B. schlechtendalii. B. medranoana has perfect flowers and all individuals bear fruits, but field observations suggested that pollen grains were absent. This study stablish that anthers start its development normaly, but at the moment that microspore mother cells start meiosis, anther's fertile tissue degenerates, so B. medranoana presents male sterility. There is evidence that the production of seeds is asexual. Some tegumentary cells produce somatic embryos. B. medranoana is a case of apomictic plant.