Dimorfismo floral: viabilidade do pólen, sementes e morfoanatomia de plântulas de Erythroxylum suberosum A. St.-Hil. (Erythroxylaceae)

Abstract

The Cerrado is one of the biodiversity hostspots. In the domain, the genus Erythroxylum is among the most occurring and Erythroxylum suberosum A. St.-Hil has a wide distribution. The species exhibit distyly, characteristic gives a variation in the pollen supply and in the fertilization established among the morphotypes. Thus, the present work was carried out to evaluate the floral dimorphism of Erythroxylum suberosum in relation to pollen viability, morphological characteristics of the fruit, seed, germination and initial seedling development in addition to identify if there is an alteration in the response pattern among physiognomies of Cerrado. Pollen grains, fruits and seedlings of the two morphotypes were evaluated with the aid of light microscopy, plus seed germination. The seeds viability produced were conducted from fruits in maturation different stage. The results demonstrated differences in pollen viability among the morphotypes and physiognomies. The fruits did not present structural differences among the studied coloration patterns. Seed germination started six days after sowing. The seedling is phanerocotylar, epigeal and of reserve (PER), exhibiting semi-photosynthetic cotyledons. Significant differences in the germination rate among the morphotypes and physiognomies were found. The characteristics presented by E. suberosum are necessary requirements for its establishment and development on the Cerrado and allows its representativeness in the domain.