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

Abstract

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.

Karyotype and nuclear DNA content of Psychotria ipecacuanha: a medicinal species

“…The same chromosomic number was also mentioned by Rout et al (2000), who used root tips obtained from somatic embryos. Souza et al (2006) not only confirmed the chromosomic number in meiotic cells, but also reported that this species exhibited small and morphologically similar metacentric chromosomes.…”

“…Identical results were obtained in Zea mays Saraiva 1993, 1997), Coffea canephora , Bixa orellana (Almeida et al 2006), Glycine max (Clarindo et al 2007) and Paullinia cupana (Freitas et al 2007). We considered these methodologies to be fundamental, as they supply more adequate chromosomic preparations in comparison with those yielded by the squashing technique (Carvalho and Saraiva 1993), usually applied in cytogenetic studies of ipecac (Assis and Giulietti 1999, Rout et al 2000, and Souza et al 2006). In accordance with Ohmido et al (1998), Guzzo et al (2000), Bauchan et al (2001), Clarindo and Carvalho (2006), Clarindo et al (2007) and Freitas et al (2007), the digital image analysis tools also contributed for providing high quality images of metaphasic cells and for discriminating subtle measurement differences in chromosomes.…”

“…Nevertheless, Assis and Giulietti (1999) and Souza et al (2006) ob-tained cytogenetic data in ipecac that contribute with taxonomy studies in this species. Apart from taxonomy, others authors have highlighted that cytogenetic information may also contribute with evolutionary (Galasso et al 2001, Doyle et al 2004) and plant breeding (Ohmido et al 1998, Harper and Cande 2000, Klein et al 2000, Galasso et al 2001, Stephens et al 2004 researches.…”

Reproductive studies in ipecac (Psychotria ipecacuanha (Brot.) stockes; Rubiaceae): pollen development and morphology

“…The type of the pollen storage product can be linked to the pollination mechanisms (Baker and Baker, 1979). Although most species of the family Rubiaceae present grains with three nuclei at the maturity (ElGhazaly et al, 2001), the pollen grains of P. ipecacuanha were bicellular when shed (Souza et al, 2003). Many heteromorphic species have binucleate pollen (Vuilleumier, 1967).…”

“…The sexual process seems to be as important to the reproduction of this species as the vegetative propagation. Reproductive studies were carried out on these same accessions of ipecac by Souza et al (2006). The pollen viability was analyzed and the percentages ranged between brevistylous and longistylous floral morphs (85.3 to 93.1%), and among the different localities (82.5 to 92.6%).…”