GENETIC VARIABILITY OF WILD AND COMMERCIAL PASSION FRUIT (Passiflora edulis Sims.) ACCESSIONS USING RAPD MARKERSABSTRACT -There are a great diversity of colors, sizes and aromas of fruits in wild accessions of P. edulis in Brazilian Savannah. These accessions are also important resistance sources against illness which can be incorpored in passionfruit breeding programs. In this work, the objetive was to evaluate the genetic variability in wild and commercial P. edulis accessions using RAPD markers. The genomic DNA of each accession was extracted and amplified using thirteen decamer primers (OPD-04, OPD-07, OPD-08, ) to obtain RAPD markers. These markers were transformed in binary matrix data to estimate genetic distances among accessions and to perform cluster and graphical dispersion analysis. A total of 187 markers were generated, and only 28 (14.97%) of them were monomorphic. The genetic distances among the 15 P. edulis accessions varied from 0.091 to 0.496. The molecular markers demonstrated the high genetic variability of the wild and commercial P. edulis accessions. The accessions with yellow fruits presented greater genetic distances in relation to the accessions with purple fruits. Lower genetic distances were verified among the accesses of the same geographical origin.

One of the current challenges of tropical fruit crop improvement is to incorporate molecular marker-based approaches into conventional breeding programmes. This study was designed to build an integrated genetic map of the sweet passion fruit (Passiflora alata), a diploid (2n = 18) outcrossing species which is greatly appreciated for in natura consumption, and reported to inspire cosmetic and pharmaceutical companies to create plant-derived compounds. With this in mind, a full-sib family of 180 individuals was genotyped using different molecular marker types, such as amplified fragment length polymorphisms (AFLP), microsatellite-AFLP (M-AFLP), simple sequence repeats (SSR), resistance gene analogues (RGA) and target region amplification polymorphism (TRAP). On average, the rate of polymorphism between the parental genotypes was 20.3%. We also searched for single nucleotide polymorphisms (SNPs) in some AFLP bands and in seven gene fragments, and found one SNP every 87 bp. All SNPs were biallelic and occurred most frequently in putative gene fragments (81.5%) rather than in AFLP bands (60.0%) analyzed. Excellent gel profiles were obtained allowing the recognition of all types of segregation expected for a progeny of an outcrossing species. Multipoint linkage analysis was performed using OneMap software, with logarithm of the odds (LOD) score ≥ 5.6 and recombination fraction <0.5. The resulting integrated map consists of 549 markers, 2.0% of which fit a segregation ratio of 1:1:1:1, 1.3% a ratio of 1:2:1, 27.3% a ratio of 3:1 and 69.4% a ratio of 1:1. The map spanned a total of 2073.0 cM, with an average distance between adjacent markers of 3.8 cM. This is the first linkage study on sweet passion fruit and should prove useful for quantitative trait loci mapping.

Yellow and sweet passion fruit are insect-pollinated species native to the tropics. Fruits are used commercially for human consumption worldwide. The yellow passion fruit is an outcrossing species with selfincompatible flowers. However, the reproductive system of the sweet passion fruit (Passiflora alata) has not been well elucidated. The objective of this work was to characterize aspects of the mating system in the sweet passion fruit using random amplified polymorphic DNA (RAPD) and microsatellite markers, particularly the rate of outcrossing in P. alata progenies. A multilocus outcrossing rate of t m = 0.994 was determined from RAPD and t m = 0.940 from microsatellites, supporting P. alata as an outcrossing species. The fixation indices of the maternal generation (F m ) were )0.200 and 0.071 with RAPD and microsatellite loci, respectively, indicating the absence of inbreeding in the maternal generation. The paternity correlation (r p ) varied from )0.008 with RAPD markers to 0.208 with microsatellite markers, suggesting a low probability of finding full sibs within the progenies. The results demonstrated that all progenies assessed in this study were derived from outcrossing.The genus Passiflora is comprised of over 400 species, 120 of which are native to Brazil. South America is considered the main centre of Passiflora genetic diversity and species are distributed from sea level to the Andes Mountains. Yellow passion fruit (Passiflora edulis Sims f. flavicarpa Deg.) and sweet passion fruit (P. alata Curtis) are grown commercially for their edible and aromatic fruits and used in juice concentrate blends consumed worldwide. In addition, the plant leaves, and to a lesser extent fruit pulp contains passiflorine, a substance with sedative and antispasmodic action used in the pharmaceutical industry (Rudnicki et al. 2007).Yellow passion fruit is an outcrossing species with perfect, self-incompatible (Bruckner et al. 1995, Rego et al. 2000 insect-pollinated flowers. However, the reproductive system of the sweet passion fruit has not been well elucidated, which is essential to establish strategies for selection and improvement, and to propose effective approaches for conservation (Endels et al. 2007). Braga et al. (2005) suggested that sweet passion fruit is an outcrossing species, with levels of self-sterility easily overcome artificially.Intrinsic factors such as flower colour and morphology, and environmental attributes including pollinator behaviour and flowering plant abundance can indicate the mating system of a plant species (Varassin et al. 2001, Parzies et al. 2008). In addition, the rate of outcrossing (t) is a key parameter of the mating system best estimated using genetic markers generated from plant progenies (Baye and Becker 2004). It measures the fraction of seeds in a given population generated by outcrossing; when t = 0, population is completely autogamous and when t = 1 population is panmitic. The complement is the fraction because of selfing, s = 1 ) t. There are two possibilities for computing the...

BackgroundThe macauba has been identified as the most promising native species for the production of vegetable oil and biomass. Several studies confirm its potential for numerous purposes (liquid and solid biofuels, food, cosmetics and pharmaceuticals), but this Brazilian biodiversity resource has been little explored, and work aimed at their domestication and genetic improvement are relatively recent. This study consisted of a multivariate approach to levels of trans fatty acids, oil yield and physical characteristics found in fruits of macauba of natural populations. The objective was to quantify the genetic variability among 35 genotypes of natural populations of macauba from 16 locations in different regions of Brazil. Euclidean Distance measurements were estimated and the cluster analysis obtained by the UPGMA method considering separately the fatty acid profile, and traits related to physical part and the fruits oil content.ResultsIt was observed the formation of seven groups for the profile of fatty acids and five groups for physical characteristics and oil yield. Large variations were observed for different types of mesocarp (pulp) fatty acids and kernel. Oleic acid (18: 1) in mesocarp was the largest contribution to the total divergence. The results indicate variations to the physical characteristics and oil yield, especially the oil percentage in mesocarp and weight of the whole fruit which contributed 64.58 % of the divergence between genotypes.ConclusionsThe study identified genotypes potential to generate variability and obtaining selection gains, directing plant breeding programs according with demands of oils market.