Mecanismos intercomplementares de autopolinização em Sida cordinfolia (Malvaceae)

Abstract

Sida is one of the most popular genres of Malvaceae, family where there are records of very complex mechanisms of self-pollination. Since this genus has one autogamy preponderant, reason for his success as ruderal, this situation led us to question about its possible self-pollinaton mechanisms. To elucidate this issue, floral biology and breeding system of Sida cordifolia were studied in urban area in the Zona da Mata, Pernambuco - Brazil. The corolla configuration, the slender stilettos and anthers lumped; as well as, the beginning of anther dehiscence with the unopened flower and stigma remaining receptive until the wilt; are factors that contribute to their self-pollination events. Were recorded and tested two types of spontaneous self-pollinaton mechanisms: one similar to cleistogamy of pre-anthesis and the other being the late self-pollination by corolla movements action; such mechanisms act in a complementary way, being this the first record of this type for this family. The spontaneous self-pollination in species cause high fruit production, reaching the cross or mixed pollination level, which optimizes the different environments occupation, including those highly anthropized.