Compatibilidade anatômica de pereiras e marmeleiros enxertados nos porta-enxertos Pyrus calleryana e Chaenomeles sinensis

The objective of this work was to evaluate the graft growth and the anatomical characterization of pear (Pyrus communis x P. pyrifolia) and quince (Cydonia oblonga) cultivars grafted on Pyrus calleryana and Chaenomeles sinensis rootstocks. Sprouted graft percentages at 60 days and the length and diameter of the graft sproutings at 120 days were evaluated. Stem cuttings from the grafting region were performed in transversal and longitudinal sections, and the secondary xylem was separated for tissue comparison. The pear trees showed good development on P. calleryana rootstock, and the anatomical sections showed that the vascular tissues were connected, which did not occur when the trees were grafted on C. sinensis, in which the grafts sprouted, but did not develop, and the vascular tissues did not connect. The quince trees showed good development on both rootstocks due to the good connection of the vascular tissues. The connection of vascular tissues is essential for the success of grafting. The evaluated species did not differ significantly as to their secondary xylem tissues. The incompatibility found between the pear trees and the C. sinensis rootstocks is not anatomical.O objetivo deste trabalho foi avaliar o crescimento dos enxertos e a caracterização anatômica de cultivares de pereira e marmeleiro enxertadas nos porta-enxertos Pyrus calleryana e Chaenomeles sinensis. Foram feitas avaliações quanto às percentagens dos enxertos brotados aos 60 dias e quanto ao comprimento e o diâmetro da brotação dos enxertos aos 120 dias. Cortaram-se porções caulinares da região da enxertia, em seções transversais e longitudinais, e o xilema secundário foi separado para comparação dos tecidos. As pereiras apresentaram bom desenvolvimento sobre o porta-enxerto P. calleryana, e os cortes anatômicos apresentaram tecidos vasculares conectados, o que não ocorreu quando as pereiras foram enxertadas em C. sinensis, em que os enxertos brotaram mas não se desenvolveram, e os tecidos vasculares não se conectaram. Os marmeleiros apresentaram bom desenvolvimento em ambos os porta-enxertos, em razão da boa conexão dos tecidos vasculares. A conexão dos tecidos vasculares é fundamental para o sucesso da enxertia. As espécies utilizadas não diferiram significativamente quanto a seus tecidos do xilema secundário. A incompatibilidade encontrada entre as pereiras e o porta-enxerto C. sinensis não é anatômica

Observing the Evolution of the Universe

How did the universe evolve? The fine angular scale (l>1000) temperature and polarization anisotropies in the CMB are a Rosetta stone for understanding the evolution of the universe. Through detailed measurements one may address everything from the physics of the birth of the universe to the history of star formation and the process by which galaxies formed. One may in addition track the evolution of the dark energy and discover the net neutrino mass. We are at the dawn of a new era in which hundreds of square degrees of sky can be mapped with arcminute resolution and sensitivities measured in microKelvin. Acquiring these data requires the use of special purpose telescopes such as the Atacama Cosmology Telescope (ACT), located in Chile, and the South Pole Telescope (SPT). These new telescopes are outfitted with a new generation of custom mm-wave kilo-pixel arrays. Additional instruments are in the planning stages.Comment: Science White Paper submitted to the US Astro2010 Decadal Survey. Full list of 177 author available at http://cmbpol.uchicago.ed

Polymorphism analysis of the CTLA-4 gene in paracoccidioidomycosis patients

The CTLA-4 protein is expressed in activated T cells and plays an essential role in the immune response through its regulatory effect on T cell activation. Polymorphisms of the CTLA-4 gene have been correlated with autoimmune, neoplastic and infectious illnesses. This work aimed to verify possible associations between single nucleotide polymorphisms (SNPs) in CTLA-4, -318C/T in the promoter and +49A/G in exon 1 and paracoccidioidomycosis (PCM) caused by Paracoccidioides brasiliensis. For this purpose, 66 chronic form PCM patients and 76 healthy controls had their allele, genotype and haplotype frequencies determined. The genetic admixture structure of the patients and controls was evaluated to eliminate ancestral bias. The comparison of frequencies indicated no significant differences between patients and controls that could link the SNPs to PCM. Groups were admixture matched with no difference observed in population ancestry inference, indicating that the absence of association between CTLA-4 polymorphisms and PCM could not be attributed to ancestral bias. This study showed that there was no association between the CTLA-4 SNPs -318 and +49 and the resistance or susceptibility to PCM

Rooting of stem segments from fig tree cultivars

Although Brazil is the largest fig (Ficus carica L.) producer in the Southern Hemisphere, it mainly uses only one cultivar, ‘Roxo de Valinhos’. In addition, propagation is almost entirely through hardwood cuttings. Therefore, the aim of this study was to establish a propagation method that provides more successful rooting of stem segments of fig cultivars for the purpose of expanding the genetic base of the fig tree. The cultivars used were ‘Brunswick’, ‘Calabacita’, ‘Negro de Bursa’, ‘Mini Figo’, ‘Lampa Preta’, ‘Lemon’, ‘Troiano’,’ Nazaré’, ‘Três num Prato’, ‘Princesa’, ‘Colo de Dama’, ‘Montes’, ‘Bêbera Branca’, ‘Pingo de Mel’, and ‘Roxo de Valinhos’. The propagation methods used were layering, hardwood cuttings, nodal segments, herbaceous cuttings originating from the removal of sprouts, and herbaceous cuttings obtained during growth. We found that the propagation method influences the rooting of stem segments, and cultivars differ in their rooting potential.

Estimates for Genetic Variance Components in Reciprocal Recurrent Selection in Populations Derived from Maize Single-Cross Hybrids

This study was carried out to obtain the estimates of genetic variance and covariance components related to intra- and interpopulation in the original populations (C0) and in the third cycle (C3) of reciprocal recurrent selection (RRS) which allows breeders to define the best breeding strategy. For that purpose, the half-sib progenies of intrapopulation (P11 and P22) and interpopulation (P12 and P21) from populations 1 and 2 derived from single-cross hybrids in the 0 and 3 cycles of the reciprocal recurrent selection program were used. The intra- and interpopulation progenies were evaluated in a 10×10 triple lattice design in two separate locations. The data for unhusked ear weight (ear weight without husk) and plant height were collected. All genetic variance and covariance components were estimated from the expected mean squares. The breakdown of additive variance into intrapopulation and interpopulation additive deviations (στ2) and the covariance between these and their intrapopulation additive effects (CovAτ) found predominance of the dominance effect for unhusked ear weight. Plant height for these components shows that the intrapopulation additive effect explains most of the variation. Estimates for intrapopulation and interpopulation additive genetic variances confirm that populations derived from single-cross hybrids have potential for recurrent selection programs