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ResumoAnálise do comportamento meiótico em Cordia ecalyculata Vell. (Boraginaceae). A espécie Cordia ecalyculata pertence à família Boraginaceae, é conhecida popularmente por café de bugre. Para ins medicinais é indicada como tônico, diurético, anti-inlamatório e inibidor do apetite. Visando contribuir para um melhor entendimento da espécie, inlorescências jovens de seis indivíduos foram coletadas e ixadas em solução de etanol e ácido acético (3:1) por 24 h. As lâminas foram preparadas utilizando a técnica de esmagamento e coradas com carmim acético a 1%. Durante a microsporogênese poucas irregularidades foram encontradas, as mais frequentes estão relacionadas à segregação irregular dos cromossomos, tais como: Ascensão precoce para os polos em metáfase I e II, bivalente não orientado em metáfase I e II, e cromossomos retardatários em anáfase I e II, levando a formação de micronúcleos. Outra irregularidade observada esta relacionada a organização das ibras dos fusos em meiose II, que se organizam na forma em T e V. Na coniguração de fuso na forma de V ocorreu fusão entre dois núcleos que estavam próximos, formando tríade ao invés de tétrade, levando à formação de micrósporos 2n inal da meiose. Entretanto, as irregularidades observadas não comprometeram a fertilidade da espécie em análise, uma vez que a viabilidade dos grãos de pólen variou de 95,42% a 100%. AbstractCordia ecalyculata belongs to the Boraginaceae family, and is commonly known as buggy coffee. It is indicated for medicinal use as a tonic, diuretic, anti-inlammatory and appetite suppressant. Young inlorescences of Biotemas, 27 (4): 21-27, dezembro de 2014 ISSNe 2175-7925 http://dx.doi.org/10.5007/2175 Revista Biotemas, 27 (4), dezembro de 2014 22 D. Nascimento et al. six individuals were collected and ixed in a mixture of ethanol and acetic acid (3:1) for 24 hours. The slides were prepared by crushing and staining tissue with 1% acetic carmine. During microsporogenesis some irregularities were observed, mostly frequently related to irregular chromosome segregation. Irregularities included: precocious migration to poles in metaphase I and II, disoriented bivalent chromosomes at metaphase I and II, laggard chromosomes in anaphase I and II, and micronuclei formation. We also observed irregular spindle organization in meiosis II, leading to 'T' and 'V' shaped spindle conigurations. In the V-shaped coniguration, two nearby nuclei fused, forming triads instead of tetrads; this lead to formation of 2n microspore at the end of meiosis. However, pollen grain viability was not compromised, as pollen grain viability varied between 95.42% and 100%.

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The subtribe Eugeniinae comprises of two genera, Eugenia (ca. 1,100 species) and Myrcianthes (ca. 40 species). Eugenia is the largest genus of neotropical Myrtaceae and its latest classification proposes 11 sections. This study describes the seed anatomy of forty-one species of Eugeniinae in order to provide possible diagnostic characteristics. Following standard anatomical techniques, flower buds, flowers, and fruits were processed and analyzed using microtome sections and light microscopy. The phylogeny used the regions ITS, rpl16, psbA-trnH, trnL-rpl32, and trnQ-rps16, following recent studies in the group. Ancestral character reconstruction uncovered that: (1) the ancestral ovule in Eugeniinae was campylotropous (98.9% probability), bitegmic (98.5% probability), and unitegmic ovules arose on more than one lineage independently within Eugenia; (2) the pachychalazal seed-coat appeared with a 92% probability of being the ancestral type; (3) non-lignified seed-coat (24,5% probability) and aerenchymatous mesotesta (45.8% probability) are diagnostic characters in Myrcianthes pungens (aerenchymatous mesotesta present in the developing seed-coat) and in the species of E. sect. Pseudeugenia until the species of E. sect. Schizocalomyrtus and it is the type of seed-coat that predominates in most basal sections on the tree; (4) the partial sclerification (only in the exotesta—exotestal seed-coat) is mainly observed in species of E. sect. Excelsae, E. sect. Jossinia (group X), and E. sect. Racemosae (22.2% probability); (5) and in the species of the recent lineages of Eugenia, with a probability of 27.2%, predominate the exomesotestal or testal construction of the seed-coat [character observed in almost all species analyzed of E. sect. Jossinia (group Y) and E. sect. Umbellatae]. A dehiscent fruit is considered as a plesiomorphic state in Myrtaceae; the ancestor of this family had seeds with a completely sclerified testa, and the other testa types described for the current species with dehiscent and indehiscent fruits are simplified versions of this ancestral type. Perhaps, this means that the sclerified layers in the seed-coat have remained in whole or in part as a plesiomorphic condition for taxa with a capsule and bacca. Maintaining the plesiomorphic condition may have represented a selective advantage at some point in the evolutionary history of the family and its groups.