Micropropagation of a recalcitrant pine (Pinus pinea L.): An overview of the effects of ectomycorrhizal inoculation

Stone pine (Pinus pinea L.) is an economically important forest species in some regions of Iberian Peninsula. Portugal and Spain have nearly 500,000 ha of stone pine stands, representing 85% of worldwide distribution. The main use of this species is for the production of seeds (pinion) for food industry. In addition to its enormous profitability as a producer of seeds, it has beneficial impact on soil protection, dunes fixation and is a pioneer species particularly for cork and holm oaks degraded ecosystems. Stone pine plantations are today a major source of income for forestry holdings. Investments have targeted breeding, reforestation, forest management and harvesting. The maternal inheritance of desirable characteristics such as cone weight, number of seeds per cone and seed length is considerably high in this species thus encouraging the selection of seeds from “plus” trees. The selected trees have been propagated by grafting and micropropagation. However, grafting generates high variability due to scion-rootstock interaction that varies production levels. The production of clonal plants from selected seeds by micropropagation techniques has advanced very slowly due to the recalcitrance of this species in tissue culture and particularly to adventitious rooting of microshoots. Due to the tremendous importance of developing a reproducible tissue culture method for clonal propagation, a study has been carried out for over a decade to enhance rooting and acclimation. During this period of time, continuous increments in the multiplication rate and rooting frequency were achieved by introducing variations in culture media composition and conditions. Auxins, carbohydrates, light quality and duration, temperature at different concentrations and levels as well as compounds such as coumarin; salicylic acid, polyamines, etc. were tested for induction and expression phases of adventitious rooting. Despite these efforts, microshoots regenerated through organogenesis from mature embryo cotyledons failed to root or to have sustained root growth. At this point, an in vitro co-culture technique of stone pine microshoots with ectomycorrhizal-fungi was introduced to overcome the adventitious root growth cessation in vitro and improve root development during acclimation phase. An overview of the results showing the positive effect of fungal inoculation in promoting root growth in vitro and on plantlet survival during acclimation will be presented. Preliminary results of biochemical signals between Pinus pinea/Pisolithus arhizus during early steps of in vitro culture detected by liquid chromatography-mass spectrometry that might be responsible for the positive effect on root growth will be also presented

Differentially expressed genes involved in lipid metabolism in the muscle tissue of Alentejano and Bísaro pig breeds

The Alentejano (AL) and Bísaro (BI) pigs stand as the predominant local breeds raised in Portugal. AL pigs are characterized by lower growth rates and precocious and higher lipid deposition, particularly of monounsaturated fatty acids, when compared to BI pigs. Lipid and fatty acids composition of meat and meat products are important features for consumers health, and gene expression is a decisive process determining fatty acid composition and deposition rates in the muscle tissue of every mammal. This study investigates the transcriptomic fundamentals associated to the phenotypical differences through a real-time qPCR approach on a set of candidate genes responsible for regulating lipid metabolism processes. Longissimus lumborum samples were collected at slaughter from five animals of each breed raised under similar conditions until ~150kg BW. Total RNA was extracted, and target cDNA was amplified to estimate expression levels when compared to endogenous control genes. Several lipogenic related genes were found to be overexpressed in the AL breed including ACLY (log2FC=0.50, p<0.05), ELOVL6 (log2FC=0.67, p<0.01), ME1 (log2FC=0.78, p<0.05), while other major lipogenic markers, such as FASN (log2FC=0.45, p=0.09) and ACACA (log2FC=0.28, p=0.17) did not attain statistical significancy, but indicate a tendency towards AL. The gene coding for the central appetite regulation hormone (LEP) was detected as significantly overexpressed in AL (log2FC=1.60, p<0.05), which may suggest the occurrence of leptin resistance in this breed, comparable to what happens with the genetically similar Iberian pig, failing to decrease feeding and increase stored energy expenditure. Similarly, adiponectin resistance is predicted to have developed in AL pigs since higher ADIPOQ levels (log2FC=0.90, p<0.01) are associated with leaner animals due to the activation of fatty acid oxidation pathways by this regulator. These results agree with the previously described high intramuscular fat content profile of the AL breed, essential in enhancing the overall sensory quality of its meat and meat products

Eléctrodo de terra em serpentina

Este artigo tem como principal objectivo a divulgação de uma aplicação informática para calcular a resistência de difusão de eléctrodos de terra em serpentina, a qual é representada analiticamente por uma sinusóide. No cálculo da resistência utilizou-se o chamado método da matriz, desenvolvido por S. Meliopoulos. Como a distribuição de potencial no solo obedece à equação de Laplace, o eléctrodo de terra é previamente discretizado em pontos-fonte de corrente eléctrica, situados no eixo dos condutores. O modelo discreto é representável por um sistema de equações lineares que permite calcular as correntes dos pontos-fonte, arbitrando uma tensão no eléctrodo. A corrente deste é a soma das correntes pontuais, e a lei de Ohm permite calcular facilmente a resistência de terra. Os resultados permitem observar que a resistência da serpentina diminui com o aumento do número de máximos, com o aumento da profundidade de enterramento e com o aumento da largura da vala. Conclui-se da utilidade da serpentina, comparada com o simples cabo horizontal, já que possui resistência de terra menor

Differential role of entorhinal and hippocampal nerve growth factor in short- and long-term memory modulation

Afghanistan - Primitive wellColorVolume 33, Page

UV Spectroscopy of Metal-Poor Massive Stars in the Small Magellanic Cloud

The Hubble Space Telescope has provided the first clear evidence for weaker winds of metal-poor massive stars in the Small Magellanic Cloud, confirming theoretical predictions of the metallicity dependence of mass-loss rates and wind terminal velocities. For lower luminosity O-type stars however, derived mass-loss rates are orders of magnitude lower than predicted, and are at present unexplained.Comment: 4 pages, 3 figures. To appear in 'The Impact of HST on European Astronomy', Eds., G. De Marchi & F.D. Macchetto, Astrophysics & Space Science, Springe

In vitro cultivation of Brosimum gaudichaudii Tréc. (Moraceae)

O objetivo desta pesquisa foi avaliar o potencial organogenético de entrenós, discos foliares, e raízes de Brosimum gaudichaudii utilizando 12 diferentes combinações dos fitorreguladores 6-benzilaminopurina e ácido naftaleno acético, em meio MS (diluído à metade), sólido (6,5 g de ágar), e com 20 g.L-1 de sacarose. Independentemente das combinações hormonais testadas verificou-se a formação de calos friáveis (2 a 20 mm de diâmetro) em 90% dos entrenós usados como explantes. No entanto, os tratamentos testados não foram capazes induzir calos ou gemas em raízes e em discos foliares. O estudo anatômico revelou a formação de meristemóides nas regiões mais externa e mais interna dos calos. Os resultados obtidos poderão servir de base para novos testes de indução de calos na espécie.The objective of this research was to evaluate the organogenic potential of internodes, leaf discs and roots of Brosimum gaudichaudii using 12 different combinations of the plant growth regulators 6-benzylaminopurine and naphthalene acetic acid in MS medium (half strength), solid medium (6.5 g agar) and sucrose medium (20 g.L-1). Regardless the hormonal combination tested, we observed the formation of friable calluses (2 - 20 mm wide) in 90% of the internode explants. However, the treatments were not able to induce callus or buds on roots and leaf discs. The anatomical analysis revealed meristemoid formation in the outer and inner regions of the calluses. The results may serve as the basis for further testing of callus induction in this species

Sr-Nd isotope signatures of surficial sediments from the Portuguese continental shelf

This study focus on the Sr-Nd isotope signatures of detrital and carbonate fractions of seven samples from surficial sediments deposited in the Portuguese continental shelf. 87Sr/86Sr and 143Nd/144Nd isotope compositions of the lithic component are used to constrain potential endmember contributions and determine sediment provenance. The 87Sr/86Sr ratios measured in the acid leachates of the seven sediment samples (carbonate fraction) lie within the range 0.7088 – 0.7092, close to the value for modern seawater (0.7091 – 0.7092), suggesting a dominant biogenic origin for this component. In contrast, the Sr isotope signatures for acid-leached silicate residues (lithic fraction) from the same samples are widely variable (87Sr/86Sr = 0.7179 to 0.7346) reflecting the input of terrigenous particles from three distinct sources (northern Iberian Variscan crust, southern Iberian Variscan crust and North African aerosols). The narrow range of ƐNd(0) values displayed by these samples (-8.5 to -10.6) does not allow effective discrimination between the different endmembers

QUANTIFICATION OF CALCIUM IN SPARKLING WINES BY INFRARED SPECTROSCOPY

Markets are increasingly competitive and the companies feel the urge to improve their manufacturing processes. Blending that with a larger control of quality and safety it was created a need to develop new methods of analysis each time more accurate, faster and with lower costs. Alentejo is a region with a wide variety of soils, most of them are rich in calcium and potassium. In the production of sparkling wine many wineries use encapsulated yeast in alginate beads, instead of the traditional method, champenoise. The first method is faster, allowing a more versatile production, reducing the risk of contamination and features organoleptic characteristics similar to the traditional method (yeast free). However, encapsulated yeast spheres should be only used if the base wine matches a number of features, among them calcium content. In this study the calcium content in the wine was determined by atomic absorption spectroscopy (AAS) and by near-infrared spectroscopy. The AAS is a high sensitivity method clearly produces a reliable result, however it is very time consuming and produces great quantities of environmental waste, therefore the possibility of using near-infrared spectroscopy as a method was studied to be a fast, simple and clean alternative to the AAS. It was obtained a calibration model with a variation coefficient higher than 0.80 which indicates that the near-infrared spectroscopy as an adequately alternative the ASS

Generate disaggregated soil allocation data using a minimum cross entropy model

Montado ecosystem in the Alentejo Region, south of Portugal, has enormous agro-ecological and economics heterogeneities. A definition of homogeneous sub-units among this heterogeneous ecosystem was made, but for them is disposal only partial statistical information about soil allocation agro-forestry activities. The paper proposal is to recover the unknown soil allocation at each homogeneous sub-unit, disaggregating a complete data set for the Montado ecosystem area using incomplete information at sub-units level. The methodological framework is based on a Generalized Maximum Entropy approach, which is developed in thee steps concerning the specification of a r order Markov process, the estimates of aggregate transition probabilities and the disaggregation data to recover the unknown soil allocation at each homogeneous sub-units. The results quality is evaluated using the predicted absolute deviation (PAD) and the “Disagegation Information Gain” (DIG) and shows very acceptable estimation errors