BackgroundBanana cultivars are mostly derived from hybridization between wild diploid subspecies of Musa acuminata (A genome) and M. balbisiana (B genome), and they exhibit various levels of ploidy and genomic constitution. The Embrapa ex situ Musa collection contains over 220 accessions, of which only a few have been genetically characterized. Knowledge regarding the genetic relationships and diversity between modern cultivars and wild relatives would assist in conservation and breeding strategies. Our objectives were to determine the genomic constitution based on Internal Transcribed Spacer (ITS) regions polymorphism and the ploidy of all accessions by flow cytometry and to investigate the population structure of the collection using Simple Sequence Repeat (SSR) loci as co-dominant markers based on Structure software, not previously performed in Musa.ResultsFrom the 221 accessions analyzed by flow cytometry, the correct ploidy was confirmed or established for 212 (95.9%), whereas digestion of the ITS region confirmed the genomic constitution of 209 (94.6%). Neighbor-joining clustering analysis derived from SSR binary data allowed the detection of two major groups, essentially distinguished by the presence or absence of the B genome, while subgroups were formed according to the genomic composition and commercial classification. The co-dominant nature of SSR was explored to analyze the structure of the population based on a Bayesian approach, detecting 21 subpopulations. Most of the subpopulations were in agreement with the clustering analysis.ConclusionsThe data generated by flow cytometry, ITS and SSR supported the hypothesis about the occurrence of homeologue recombination between A and B genomes, leading to discrepancies in the number of sets or portions from each parental genome. These phenomenons have been largely disregarded in the evolution of banana, as the “single-step domestication” hypothesis had long predominated. These findings will have an impact in future breeding approaches. Structure analysis enabled the efficient detection of ancestry of recently developed tetraploid hybrids by breeding programs, and for some triploids. However, for the main commercial subgroups, Structure appeared to be less efficient to detect the ancestry in diploid groups, possibly due to sampling restrictions. The possibility of inferring the membership among accessions to correct the effects of genetic structure opens possibilities for its use in marker-assisted selection by association mapping.

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High yield stability and adaptability of yellow passion fruit varieties (Passifl ora edulis Sims. f. fl avicarpa Deg.) are highly desirable attributes when exploring different environments.This study aimed to evaluate the adaptability and yield stability of yellow passion fruit varieties using AMMI (additive main effects and multiplicative interaction) and other ancillary statistics.Twelve varieties were evaluated in eight environments. Analysis of variance showed effects attributable to the varieties (G), environment (E) and their interaction (G×E). The fi rst two multiplicative components of the interaction accounted for 69% of the sum of squares. The scores of the principal interaction components showed high variability for the environments relative to the variety effects. High varietal phenotypic stability was observed in three environments; which can be used in yellow passion fruit breeding programs for initial selection trials. A biplot-AMMI analysis and yield stability index incorporating the AMMI stability value and yield capacity in a single non-parametric index were useful for discriminating genotypes with superior and stable fruit yield. AMMI analysis also allowed for the identifi cation of more productive varieties in specifi c environments, leading to signifi cant increase in passion fruit productivity.

-The objective of this study was to evaluate the influence of pH on in vitro germination

Despite the ecological and economic importance of passion fruit (Passiflora spp.), molecular markers have only recently been utilized in genetic studies of this genus. In addition, both basic genetic researches related to population studies and pre-breeding programs of passion fruit remain scarce for most Passiflora species. Considering the number of Passiflora species and the increasing use of these species as a resource for ornamental, medicinal, and food purposes, the aims of this review are the following: (i) to present the current condition of the passion fruit crop; (ii) to quantify the applications and effects of using molecular markers in studies of Passiflora; (iii) to present the contributions of genetic engineering for passion fruit culture; and (iv) to discuss the progress and perspectives of this research. Thus, the present review aims to summarize and discuss the relationship between historical and current progress on the culture, breeding, and molecular genetics of passion fruit.

The propagation of many passion fruit species (Passiflora spp.) is done by seeds or sexual method, although asexual propagation, such stem cuttings, grafting or tissue culture is also possible and very useful in many cases. In this work, it was presented information on scientific and technological advances in sexual and asexual propagation of passion fruit, considering the different propagation methods and their applications. New demands for research and development activities are also related, given the wide range of passion fruit species and its potential for food, ornamental and medicinal use.

• Premise of the study: We developed the first microsatellites for Passiflora setacea and characterized new sets of markers for P. edulis and P. cincinnata, enabling further genetic diversity studies to support the conservation and breeding of passion fruit species.• Methods and Results: We developed 69 microsatellite markers and, in conjunction with assessments of cross-amplification using primers available from the literature, present 43 new polymorphic microsatellite loci for three species of Passiflora. The mean number of alleles per locus was 3.1, and the mean values of the expected and observed levels of heterozygosity were 0.406 and 0.322, respectively.• Conclusions: These microsatellite markers will be valuable tools for investigating the genetic diversity and population structure of wild and commercial species of passion fruit (Passiflora spp.) and may be useful for developing conservation and improvement strategies by contributing to the understanding of the mating system and hybridization within the genus.

RESUMOO programa de melhoramento genético de bananeira da Embrapa Mandioca e Fruticultura Tropical visa desenvolver e selecionar novas cultivares de bananeira com alta produtividade, bom sabor dos frutos e que apresentem resistência às principais doenças. Objetivou-se com este trabalho avaliar cultivares e híbridos de bananeira visando a identificação de genótipos superiores em produtividade e resistência a doenças. Foram avaliados os híbridos da cv. Gros Michel (Calipso, Bucaneiro e Ambrosia); da cv.Yangambi (YB42-21 e YB42-17); da cv. Prata (ST42-08 e ST12-31) e de Prata-Anã (SH3640) e as cultivares Pacovan e Nanicão. As características utilizadas para as avaliações foram: altura da planta (m); diâmetro do pseudocaule (cm); número de folhas vivas na floração; número de folhas vivas na colheita; número de frutos por cacho; peso do cacho (kg); peso médio de frutos (g); comprimento do fruto (cm); diâmetro do fruto (cm); espessura da casca (mm); número de dias do plantio à floração e número de dias do plantio à colheita. Usou-se o delineamento em blocos casualizados com 10 tratamentos, cinco repetições e seis touceiras por parcela, espaçadas de 2,00 m x 3,00 m. Os híbridos avaliados apresentaram características agronômicas iguais ou superiores as cultivares que lhes deram origem. Os melhores híbridos de Prata , Yangambi e Gros Michel foram respectivamente, ST12-31, YB42-21 e Bucaneiro. Termos de indexação:Musa spp., produção, genótipos, ciclo da cultura, porte da planta. ABSTRACTThe banana genetic breeding program at Embrapa Cassava and Tropical Fruits aims to develop and select new banana varieties with high productivity, good fruit flavor and resistance to most banana diseases. The objective of this work was to evaluate banana cultivars and hybrids in order to identify superior genotypes for productivity and disease resistance. The following characteristics were evaluated: plant height (cm); pseudostem diameter (cm); number of living leaves during flowering; and at harvest number of fingers per bunch; bunch weight (kg); mean finger weight (g); finger length (cm); finger diameter (cm); skin thickness (mm); number of days from planting to flowering and number of days from planting to harvesting in the hybrids of the Gros Michel (Calipso, Bucaneiro and Ambrosia); Yangambi (YB42-21 e YB42-17); Prata (ST42-08 e ST12-31) and Prata Anã (SH3640) and in the cultivars Pacovan (Prata Type) and Nanicão (Cavendish Type). The experiment was carried out in randomized blocks design, with 10 treatments, five replications and six bushes per plot in the spacing of 2.0 m x 3.0 m. The hybrids evaluated presented agronomic characteristics equal or superior to the corresponding varieties. The best hybrids of the Prata, Yangambi and Gros Michel were ST12-31, YB42-21 and Bucaneiro, respectively.