Reproductive studies on ipecac (Cephaelis ipecacuanha (Brot.) A. Rich; Rubiaceae): meiotic behavior and pollen viability

Estudos reprodutivos em poaia (Cephaelis ipecacuanha (Brot.) A. Rich; Rubiaceae): comportamento meiótico e viabilidade polínica

Reproductive studies were carried out on Brazilian accessions of ipecac, Cephaelis ipecacuanha. Meiotic behavior was studied using the squashing technique. Irregular chromosome segregation in meiosis I and II, many sets of chromosomes in telophase II, micronuclei, incorrect cytoplasm division, incomplete cytokinesis and anomalous post-meiotic products, mainly polyads, were observed. The mean meiotic index was lower than 72%. Pollen viability was analyzed using Alexander solution, and the percentages ranged between brevistylous and longistylous floral morphs (85.3 to 93.1%), and among different localities (82.5 to 92.6%) analyzed. The size of pollen ranged between viable and sterile, and empty and shrunken sterile. In its natural habitat, this species is known to propagate by vegetative multiplication, but sexual reproduction seems to be as important as the vegetative propagation to this species.

ipecac; heterostyly; meiosis; microsporogenesis; microgametogenesis; pollen viability

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