In vitro pollen germination and pollen viability in passion fruit (Passiflora spp.)

The use of Passiflora species for ornamental purposes has been recently developed, but little is known about pollen viability and the potential for crossing different species. The objective of this study was to evaluate the pollen viability of six Passiflora species collected from different physiological stages of development through in vitro germination and histochemical analysis using dyes. The pollen was collected in three stages (pre-anthesis, anthesis and post-anthesis). Three compositions of culture medium were used to evaluate the in vitro germination, and two dyes (2,3,5-triphenyltetrazolium chloride, or TTC, and Lugol's solution) were used for the histochemical analysis. The culture medium containing 0.03% Ca(NO3) 4H2O, 0.02% of Mg(SO4 ).7H2O, 0.01% of KNO3, 0,01% of H3BO3, 15% sucrose, and 0.8% agar, pH 7.0, showed a higher percentage of pollen grains germinated. Anthesis is the best time to collect pollen because it promotes high viability and germination. The Lugol's solution and TTC dye overestimated the viability of pollen, as all accessions showed high viability indices when compared with the results obtained in vitro.

Heterosis in papaya: inter and intragroup analysis

Papaya (Carica papaya L.) is a typical crop of tropical areas, and Brazil is one of the leading world producers. In recent decades, papaya culture has expanded to different regions of the country, but the number of cultivars available is still limited. In the present study, a complete diallel cross was carried out using eight accessions of papaya from the UENF/Caliman germplasm bank. Four genotypes belong to the Formosa heterotic group and four, to the Solo group. This study aimed to evaluate the occurrence and viability of exploring heterosis in heterotic intragroup hybrids. Fifty-six hybrid progenies were generated and evaluated. Among the Formosa intragroup hybrids, two hybrid combinations (MR x J4 and MR x SK) showed heterosis for all traits, as well as good average total fruit production. Among the Solo intragroup hybrids, three hybrid combinations (WM x GG, WM x SS and WM x SM) stand out for fruit production and high content of soluble solids. In Formosa x Solo hybrids, all hybrid combinations with the parent JS (JS x WM, JS x GG, JS x SS and JS x SM) showed high fruit quality and good average for fruit production. The heterotic profile of the hybrids tested allowed the identification of promising hybrids within Formosa and Solo heterotic groups. The analysis of the canonical variables also allowed the visualization of distinct groups of hybrids, depending on the provenance of the parents.

GENETIC DIVERSITY AND STRUCTURE OF Oenocarpus mapora GERMPLASM CONSERVED AT EASTERN AMAZON

ABSTRACT The aim of this study was to evaluate the genetic diversity and structure in the germoplasm of Oenocarpus mapora conserved at Eastern Amazon. Thus, 88 individuals were genotyped with five microsatellite loci. These individuals belong to 24 accessions that were sampled in eight sample places of three Brazilian Amazon states conserved at the Active Germplasm Bank (AGB) of Embrapa Eastern Amazon. All loci were polymorphic and they generated 85 alleles with an average of 17 alleles per loci. Total genetic diversity (HE) was 0.48. Sample places were considered genetically distinct, with ?p = 0.354. The analysis of molecular variance (AMOVA) identified that the genetic portion among areas was of 36.14% and within 63.86%. The Nei distances varied from 0.091 between Abaetetuba and Santo Antônio do Tauá, both in the state of Pará (PA), to 4.18, between Parintins, AM and Rio Branco, AC. By means of Bayesian analysis, it was identified nine clusters that compose the accessions of the germplasm bank, with different distributions among individuals. The study showed high fixation rates per sample area, which indicates that there may have been significant inbreeding or crossing among parental individuals. It suggests that future samples should be made of different plants in natural populations. Even though, it was verified that there is considerable genetic variation in the germplasm of O. mapora.

Espectrofotometria derivativa: uma estratégia simples para a determinação simultânea de corantes em alimentos

A very simple spectrophotometric method is described for resolving binary mixture of the food colorants Sunset Yellow (INS 110) and Tartrazine Yellow (INS 102) by using the first derivative spectra with measurements at zero-crossing wavelengths. Before the spectrophotometric measurements, the dyes were sorbed onto polyurethane foam and recovered in N,N-dimethilformamide. Commercial food products (gelatine and juice powder) were analysed by using the proposed method and the HPLC technique. The results are in very good agreement and the differences between the methods is not statistically important. Therefore, the first-order derivative spectrophotometric method is accurate, precise, reliable and could be applied to the routine analysis of food samples.

Estudo da reatividade do estado excitado triplete de 1,4-diaza-9-fluorenonas frente a doadores de hidrogênio e de elétron

The effect of the introduction of nitrogen atoms upon the triplet excited state reactivity of 1,4-diaza-9-fluorenone (1) and 1,4-diaza-9-benz[b]fluorenone (2), in acetonitrile, was investigated employing the nanosecond laser flash photolysis technique. The intersystem crossing quantum yield (Φces) for 1 and 2 was determined using 9-fluorenone as a secondary standard (Φces= 0.48, in acetonitrile) and for both diazafluorenones a value of Φces= 0.28 was found. Quenching rate constants ranged from 8.17x10(4) L mol-1 s-1 (2-propanol) to 1.02x10(10) L mol-1 s-1 (DABCO) for 1,4-diaza-9-fluorenone and from 6.95x10(5) L mol-1 s-1 (2-propanol) to 5.94x10(9) L mol-1 s-1 (DABCO) for 1,4-diaza-9-benz[b]fluorenone, depending if the quenching process involves energy, hydrogen or electron transfer. A comparison between quenching rate constants for both diazaflurenones and the parent compound, i.e. 9-fluorenone, a ketone with lowest triple state of ππ* configuration, lead to the conclusion that the reactive triplet excited state for 1,4-diaza-9-fluorenone and 1,4-diaza-9-benz[b]fluorenone has ππ* configuration.

Evaluation of genetic mixtures of sorghum lines for anthracnose resistance management

The main objective of this work was to evaluate the diversification of sorghum (Sorghum bicolor) populations as a way to manage resistance to the sorghum anthracnose fungus Colletotrichum graminicola. A total of 18 three-way hybrids were obtained by crossing six single cross male-sterile F1 hybrids, derived by crossing A (non restorer sterile cytoplasm) and B (non restorer normal cytoplasm) lines, with three fertile R (restorer) lines, previously evaluated for their differential reaction to the pathogen. Variation in the level of resistance was observed, as indicated by the values of the area under the disease progress curve (AUDPC) obtained for each hybrid. Lines contributed differently to the level of resistance of each hybrid. All hybrids in which CMSXS169R was the male progenitor were classified as highly resistant. Some hybrids had a level of resistance superior to the maximum levels of each line component individually.

Analysis of land use and occupancy in permanent preservation areas according to the hydrography of Ribeirão Água Fria - Bofete, SP - Brazil

The use conflicts are determined by the inadequate occupations of the soil, as it is the case of soil occupation inside of permanent preservation areas. This study aimed to determine the classes of the soil use and if there are conflicts inside of permanent preservation areas along the drainage network of the Água Fria Stream watershed, located in Bofete city - São Paulo, Brazil. It locates geographically between the coordinates: 48°09'30" to 48°18'30" longitude WGr., 22°58'30" to 23°04'30" latitude S, with an area of 15242.84 ha. The map of soil use was elaborated through the interpretation directly in the computer screen of satellite digital image. In the orbital data, the study area is inserted in the quadrant A, of image TM/Landsat - 5, orbit 220, point 76, passage 9/8th/2007. The Geographical Information System used was CartaLinx. The conflict areas of the watershed were obtained from the crossing between the maps of soil use and of PPAs. The results allowed the conclusion that more than half of the area (51.09%) is occupied by pastures, reflex of sandy soils and low fertility. It was also verified that although almost half of the watershed is covered with some type of vegetation (48.78% of natural forest /reforestation), it has approximately a third of permanent preservation areas used inappropriately by pastures (88.15%), reforestation (10.42%) and exposed soil (1.43%), totaling 343.07ha of conflicting areas, in a total of 993.26 ha of PPAs.

Prevalence of radiographic markers of femoroacetabular impingement in asymptomatic adults

OBJECTIVE: to determine the prevalence of radiographic signs of femoroacetabular impingement (FAI) in asymptomatic adults and correlate them with data from physical examinations. METHODS: We conducted a cross-sectional study with 82 asymptomatic volunteers, 164 hips, between 40 and 60 years of age, selected by convenience. They were submitted to anamnesis and clinical examination of the hip, anteroposterior (AP) pelvis radiographs with three incidences, Dunn 45° and Lequesne false profile of each hip, to measure the variables. We measured the alpha angle, anterior offset of the femoral neck, cervical diaphyseal angle, CE angle of Wiberg, acetabular index, Sharp angle, and the crossing, ischial spine and posterior wall signs. RESULTS: our sample consisted of 66% women, mean age of 50.4 years. The average alpha angle was 45.10°, SD=8.6. One quarter of the hips showed alpha angle greater than or equal to 50°; among men the prevalence was 34%, and among women, 11%. We found indicative radiographic signs of femoroacetabular impingement in 42.6% of hips, whether femoral or acetabular, and the increased alpha angle was related to the decrease in hip internal rotation (p<0.001). CONCLUSION: the radiographic findings of femoroacetabular impingement in asymptomatic patients were frequent in the studied sample. The increase in alpha angle was associated with decreased internal rotation.

Microsatellite-dense genetic map: towards genome coverage in a tropical maize (Zea mays L.) population

Dense molecular genetic maps are used for an efficient quantitative trait loci (QTL) mapping and in the marker-assisted selection programs. A dense genetic map was generated with 139 microsatellite markers using 256 F2 plants generated by the crossing of two tropical maize inbred lines (L-02-03D and L-20-01F). This map presented 1,858.61 cM in length, where 10 linkage groups were found spanned, with an average interval of 13.47 cM between adjacent markers. Seventy seven percent of the maize genetic mapping bins were covered, which means an increase of 14% coverage in relation to the previous tropical maize maps. The results provide a more detailed and informative genetic map in a tropical maize population representing the first step to make possible the studies of genetic architecture to identify and map QTL and estimate their effects on the variation of quantitative traits, thus allowing the manipulation and use in tropical maize breeding programs.

Hybridization among wild passionflower species

(Hybridization among wild passionflower species). Passion fruits are appreciated for their ornamental value, since their flowers are showy and display a wide variety of colors. In addition, many hybrids have been produced and used in other countries. The genotypes used in selection of plants with ornamental characteristics are hybrid progenies which are used in various crossing strategies. Thus, the aim of this work was to obtain interspecific hybrids, perform backcrossing and obtain progenies from crossings between hybrids, and to determine the reproductive compatibility between the progenitors involved. The percentage of fertilized flowers, germination, and the number of fruits, seeds and plants obtained through crossing were recorded. A series of 374 crossings involved seven species and two hybrids. Crossings such as Passiflora gibertii N. E. Brown vs. P. kermesina Link & Otto and P. gibertii vs. P. alata Curtis did not produce seeds. The largest percentage of fertilized flowers (86%) was recorded for the crossing P. gardneri Mast.vs. P. cincinnata Mast.; yet, the seeds produced did not show endosperm. Interspecific hybrids were obtained from the crossings P. gardneri vs. P. alata, P. watsoniana Mast.vs. P. alata, P. watsoniana vs. P. gardneri and P. gardneri vs. P. gibertii. Seeds generated from backcrossings involving the hybrids P. sublanceolata (sin. P. palmeri var. sublanceolata (Killip) J. M. MacDougal) vs. P. foetida var. foetida L. (HD13-133 and HD13-141) and F2 reached high germination percentages.

Alternative procedures for parent choice in a breeding program for the common bean (Phaseolus vulgaris L.)

Six common bean cultivars were crossed in diallel and the segregant populations were assessed in the F2 and F3 generations to compare methodologies for parental selection in a breeding program based on hybridization. The cultivars involved in the diallel were A 114, A 77, ESAL 686, Milionário, Carioca, and Flor de Mayo. The segregant F2 and F3 generations were assessed on the experimental campus of the Universidade Federal de Larvas, in July 1994. It was found that the cultivars differed in their general combining ability (GCA). Flor de Mayo, which belongs to the Durango race, had the largest positive GCA estimate for grain field, and the cultivars from the Mesoamerican race, Milionário and A 114, the smallest GCA estimates. For flowering, the cultivar that most contributed to reduced plant cycle was ESAL 686. There was agreement among the results obtained from the diallel and the estimates of the parameter m + a of the populations. However, it was evident that the estimate of genetic variance of the populations should be considered as a condition to identify the hybrid population that will produce a line with high performance.

Genetic control of characters associated with bean golden mosaic geminivirus resistance in Phaseolus vulgaris L.

Bean golden mosaic is the most important viral disease of the bean crop (Phaseolus vulgaris L.) in Latin America. The genetics of resistance to a Brazilian strain of bean golden mosaic virus (BGMV), was studied in a 4 x 4 diallel cross without reciprocals, among the parental genotypes DOR 303, EMGOPA 201 Ouro, Carnaval, and Redlands Greenleaf C. Seedlings of the four parents, six F1 hybrids, 12 backcrosses, and F2 generations for each combination were inoculated on the eighth day after sowing by exposure to a viruliferous whitefly (Bemisia tabaci Genn.) population for 24 h, in a glasshouse, prior to transplantation to field conditions. The full set of two parents, F1, F2 and respective backcrosses for each combination was considered to be a family. Data were recorded and analyzed for foliar yellowing, plant dwarfing, and pod malformation, using a randomized block design, with two replications. Weighted generation mean analysis was performed for each of the six families. An additive gene action model was significant for the three characteristics evaluated. On the other hand, non-additive gene action had greater absolute value in most cases. Resistance to foliar yellowing conferred by genes from DRO 303 was highly heritable and was expressed equally well in the different genetic backgrounds evaluated. Such resistance may be oligogenic. Broad- and narrow-sense heritabilities were relatively high for all response traits. The three traits studied were all positively correlated, indicating that they can be simultaneously selected for enhancement. The highest correlation coefficient was obtained for dwarfing x pod malformation.

Multivariate genetic divergence and hybrid performance of cacao (Theobroma cacao L.)

Genetic distances among cacao cultivars were calculated through multivariate analysis, using the D2 statistic, to examine racial group classification and to assess heterotic hybrids. A 5 x 5 complete diallel was evaluated. Over a five-year period (1986-1990), five cultivars of the S1 generation, pertaining to the Lower Amazon Forastero and Trinitario racial groups and 20 crosses between the corresponding S0 parents were analyzed, based upon five yield components - number of healthy and collected fruits per plant (NHFP and NCFP), wet seed weight per plant and per fruit (WSWP and WSWF), and percentage of diseased fruits per plant (PDFP). The diversity analysis suggested a close relationship between the Trinitario and Lower Amazon Forastero groups. A correlation coefficient (r) was calculated to determine the association between genetic diversity and heterosis. Genetic distance of parents by D2 was found to be linearly related to average performance of hybrids for WSWP and WSWF (r = 0.68, P < 0.05 and r = 0.76, P < 0.05, respectively). The heterotic performance for the same components was also correlated with D2, both with r = 0.66 (P < 0.05). A relationship between genetic divergence and combining ability effects was suggested because the most divergent cultivar exhibited a high general combining ability, generating the best performing hybrids. Results indicated that genetic diversity estimates can be useful in selecting parents for crosses and in assessing relationships among cacao racial groups.

One-winged Drosophila subobscura: a phenotype with an obscure genetic basis

A line of one-winged Drosophila subobscura was studied. The absent wing is substituted by a bulky structure with macro and microchaetes, showing a thoracic appearance. Genetic crosses showed that there is no way to select for the trait by simple crossing. The number of one-winged flies in the various generations was always low. In one case a wingless fly was also obtained. The trait presents an unknown genetic pattern.

JAK/STAT-deficient cell lines

Mutant cell lines B3 and B10, which are unresponsive to both interferon (IFN)-alpha and IFN-gamma, and line B9, which does not respond to IFN-gamma stimulation, are described. The mutants were submitted to fluorescence-activated cell sorting (FACS) from a cellular pool, which was obtained from the parental cell line 2C4 after several rounds of mutagenesis. The unresponsiveness to IFN stimulation was observed both in terms of expression of cell surface markers (CD2, class I and II HLAs) and mRNA expression of IFN-stimulated genes (2'-5' oligoadenylate synthetase (OAS), 9-27, and guanylate binding protein (GBP)). Genetic crossing of B3, B9 and B10 with U3 (STAT1-), gamma2a (JAK2-) and U4 (JAK1-) mutants, respectively, did not restore IFN responsiveness to the hybrid cell lines. However, when these cell lines were crossed with the same mutants, but using the pairwise crosses B3 x U4, B9 x U3 and B10 x U3, the cell hybrids recovered full IFN responsiveness. The present genetic experiments permitted us to assign the mutant cell lines B3, B9 and B10 to the U3, gamma2 and U4 complementation groups, respectively. These conclusions were supported by the analysis of IFN-stimulated genes in the mutants.