GERMINAÇÃO DE SEMENTES DE Piptadenia moniliformis Benth. SOB ESTRESSE HÍDRICO

O período de germinação e o estabelecimento de plântulas é um dos fatores mais importantes para a sobrevivência das espécies, principalmente nos locais em que a disponibilidade de água é limitada, como na região da Caatinga. Neste sentido, o objetivo deste trabalho foi avaliar o efeito do estresse hídrico sobre a germinação de sementes de Piptadenia moniliformis Benth. Foram utilizados três lotes (L1, L2 e L3), correspondentes aos anos de produção de 2006, 2007 e 2008, respectivamente. Antes do teste de germinação, as sementes foram escarificadas com ácido sulfúrico concentrado durante 30 minutos. Para induzir o deficit hídrico, foi utilizado o polietileno glicol (PEG 6000), nos seguintes potenciais osmóticos: - 0,3; -0,6; -0,9, -1,2 e -1,5 MPa e a água (0 MPa) sob as temperaturas de 25 e 30ºC. As características avaliadas foram: porcentagem de germinação e de plântulas normais, índice de velocidade de germinação e massa seca de plântulas. O processo germinativo de sementes de Piptadenia moniliformis Benth. é comprometido a partir de potenciais hídricos inferiores a -0,6 MPa a 25 e 30 °C; potenciais hídricos iguais ou inferiores a -1,2 MPa inibem a formação de plântulas normais nas duas temperaturas; a tolerância ao estresse hídrico simulado com PEG 6000 é variável entre lotes de sementes e temperaturas de germinação.

Fault tolerance logging-based model for deterministic systems

Fault tolerance allows a system to remain operational to some degree when some of its components fail. One of the most common fault tolerance mechanisms consists on logging the system state periodically, and recovering the system to a consistent state in the event of a failure. This paper describes a general fault tolerance logging-based mechanism, which can be layered over deterministic systems. Our proposal describes how a logging mechanism can recover the underlying system to a consistent state, even if an action or set of actions were interrupted mid-way, due to a server crash. We also propose different methods of storing the logging information, and describe how to deploy a fault tolerant master-slave cluster for information replication. We adapt our model to a previously proposed framework, which provided common relational features, like transactions with atomic, consistent, isolated and durable properties, to NoSQL database management systems.

FIELD TOLERANCE OF SELECTED VARIETIES TO AND FUNGICIDE EFFICACY AGAINST ALTERNARIA BLIGHT OF SWEET POTATO

Alternaria blight (AB) of sweet potato ( Ipomoea batatas L. ), caused by Alternaria spp., was recently reported in South Africa, but is common in southern and eastern Africa. Elsewhere in the world, AB is controlled primarily using resistant varieties. Twenty-five sweet potato varieties/breeding lines, from different origins were assessed for tolerance to AB. The materials were planted in fields having a history of AB disease and rated for tolerance based on a General Disease Index (GDI), with the lowest scores representing tolerance, and the higher scores representing susceptibility. Variety 199062-1 had the lowest GDI value, and was the most tolerant to AB; while W119 had the highest GDI value and was the most susceptible to the disease. Other varieties/breeding lines showed a variation in GDI values between most tolerant and most susceptible. Among the fungicides tested under field conditions, the mixture azoxystrobin-difenoconazole was the most effective in reducing AB intensity. Fungicides pyraclostrobin-boscalid, unizeb, azoxystrobin-chlorothalonil and cymoxanil-mancozeb were also effective against the disease.

Intraspecific individual variation of temperature tolerance associated with oxygen demand in the European sea bass (Dicentrarchus labrax)

The European sea bass (Dicentrarchus labrax) is an economically important fish native to the Mediterranean and Northern Atlantic. Its complex life cycle involves many migrations through temperature gradients that affect the energetic demands of swimming. Previous studies have shown large intraspecific variation in swimming performance and temperature tolerance, which could include deleterious and advantageous traits under the evolutionary pressure of climate change. However, little is known of the underlying determinants of this individual variation. We investigated individual variation in temperature tolerance in 30 sea bass by exposing them to a warm temperature challenge test. The eight most temperature-tolerant and eight most temperature-sensitive fish were then studied further to determine maximal swimming speed (U-CAT), aerobic scope and post-exercise oxygen consumption. Finally, ventricular contractility in each group was determined using isometric muscle preparations. The temperature-tolerant fish showed lower resting oxygen consumption rates, possessed larger hearts and initially recovered from exhaustive exercise faster than the temperature-sensitive fish. Thus, whole-animal temperature tolerance was associated with important performance traits. However, the temperature-tolerant fish also demonstrated poorer maximal swimming capacity (i.e. lower UCAT) than their temperature-sensitive counterparts, which may indicate a trade-off between temperature tolerance and swimming performance. Interestingly, the larger relative ventricular mass of the temperature-tolerant fish did not equate to greater ventricular contractility, suggesting that larger stroke volumes, rather than greater contractile strength, may be associated with thermal tolerance in this species.

Changes in Hematological Parameters and Erythrocyte Osmotic Fragility in Lame and Aged Horses Administered with Resveratrol Supplement

The study was aimed at evaluating the changes in haematological parameters and erythrocyte osmotic fragility in lame and aged horses administered with resveratrol supplement (Equithrive joint®). A total of 16 horses of both sexes, aged 18 ± 0.65 and showing lameness grade 3 were used for the study. The horses weighed 350-450 kg and comprised 8 horses which were administered with resveratrol supplement for 4 weeks and 8 others, which served as controls and given only Saccharomyces cerevisiae yeast strain used as carrier in the supplement. Blood samples were collected from each horse before supplementation and at weekly intervals for 4 weeks of the experiment. Haematological parameters and erythrocyte osmotic fragility were determined by standard methods. Equithrive joint® increased significantly (P ˂ 0.05) packed cell volume, haemoglobin concentration and erythrocyte counts in the treated horses while total leucocyte, neutrophil and eosinophil counts decreased significantly (P ˂ 0.05) in the treated horses compared with the untreated horses. Erythrocyte osmotic fragility test showed decreased haemolysis in the treated horses. The result indicated that equithrive joint® a potent antioxidant and anti-inflammatory agent maintained the membrane integrity of red blood cells and may be of value in aiding horses move with ease during ageing.

The relationship between population structure and aluminum tolerance in cultivated sorghum.

2011

Association mapping provides insights into the origin and the fine structure of the sorghum aluminum tolerance locus, AltSB.

2014

Identification of novel drought-tolerant-associated SNPs in common bean (Phaseolus vulgaris)

Common bean (Phaseolus vulgaris L.) is a leguminous in high demand for human nutrition and a very important agricultural product. Production of common bean is constrained by environmental stresses such as drought. Although conventional plant selection has been used to increase production yield and stress tolerance, drought tolerance selection based on phenotype is complicated by associated physiological, anatomical, cellular, biochemical, and molecular changes. These changes are modulated by differential gene expression. A common method to identify genes associated with phenotypes of interest is the characterization of Single Nucleotide Polymorphims (SNPs) to link them to specific functions. In this work, we selected two drought-tolerant parental lines from Mesoamerica, Pinto Villa, and Pinto Saltillo. The parental lines were used to generate a population of 282 families (F3:5) and characterized by 169 SNPs. We associated the segregation of the molecular markers in our population with phenotypes including flowering time, physiological maturity, reproductive period, plant, seed and total biomass, reuse index, seed yield, weight of 100 seeds, and harvest index in three cultivation cycles. We observed 83 SNPs with significant association (p < 0.0003 after Bonferroni correction) with our quantified phenotypes. Phenotypes most associated were days to flowering and seed biomass with 58 and 44 associated SNPs, respectively. Thirty-seven out of the 83 SNPs were annotated to a gene with a potential function related to drought tolerance or relevant molecular/biochemical functions. Some SNPs such as SNP28 and SNP128 are related to starch biosynthesis, a common osmotic protector; and SNP18 is related to proline biosynthesis, another well-known osmotic protector.

Intra- and extracellular osmotic regulation in the hololimnetic Caridea and Anomura: a phylogenetic perspective on the conquest of fresh water by the decapod Crustacea

We investigate extra- and intracellular osmoregulatory capability in two species of hololimnetic Caridea and Anomura: Macrobrachium brasiliense, a palaemonid shrimp, and Aegla franca, an aeglid anomuran, both restricted to continental waters. We also appraise the sharing of physiological characteristics by the hololimnetic Decapoda, and their origins and role in the conquest of fresh water. Both species survive salinity exposure well. While overall hyperosmoregulatory capability is weak in A. franca and moderate in M. brasiliense, both species strongly hyporegulate hemolymph [Cl-] but not osmolality. Muscle total free amino acids (FAA) increase slowly but markedly in response to the rapid rise in hemolymph osmolality consequent to hyperosmotic challenge: 3.5-fold in A. franca and 1.9-fold in M. brasiliense. Glycine, taurine, arginine, alanine and proline constitute a parts per thousand 85% of muscle FAA pools in fresh water; taurine, arginine, alanine each contribute a parts per thousand 22% in A. franca, while glycine predominates (70%) in M. brasiliense. These FAA also show the greatest increases on salinity challenge. Muscle FAA titers correlate strongly (R = 0.82) with hemolymph osmolalities across the main decapod sub/infraorders, revealing that marine species with high hemolymph osmolalities achieve isosmoticity of the intra- and extracellular fluids partly through elevated intracellular FAA concentrations; freshwater species show low hemolymph osmolalities and exhibit reduced intracellular FAA titers, consistent with isosmoticity at a far lower external osmolality. Given the decapod phylogeny adopted here and their multiple, independent invasions of fresh water, particularly by the Caridea and Anomura, our findings suggest that homoplastic strategies underlie osmotic and ionic homeostasis in the extant freshwater Decapoda.

Variação no conteúdo protéico e pigmentar em variantes cromáticas de Gracilaria domingensis nas populações naturais de Rio do Fogo-RN, BRASIL

The seaweed Gracilaria domingensis is a common species in the coast of Rio Grande do Norte. This species lives in the intertidal zone, where colour strains (red, green and brown) co-occur during the whole year. Seaweeds that live in this region are exposed to daily changes and to the rhythm of the tide. During the low tide they are exposed to dissection, hiper-or hipo-osmotic shock, high temperatures and high irradiance. The aim of this study was to analyze whether the pigment and protein content of the colour strains of G. domingensis is affected by some environmental parameters in a temporal scale. The seaweeds were collected during 10 months in the seashore of Rio do Fogo (RN). The total soluble proteins and the phycobiliprotein were extracted in phosphate buffer and the carotenoids were analyzed by a standardized method through HPLC-UV. The pigments analysis showed that phycoerithrin is the most abundant pigment in the three strains. This pigment was strongly correlated with nitrogen and the photosynthetically active radiation. Chlorophyll presented higher concentrations than carotenoids during the whole, but the ratio carotenoid/chlorophyll-a was modified by incident radiation. The most abundant carotenoid was ß-carotene and zeaxanthin, which had higher concentrations in the higher radiation months. The concentration increase of zeaxanthin in this period indicated a photoprotective response of the seaweed. The three strains presented a pigment profile that indicates different radiation tolerance profile. Our results pointed that the green strain is better adapted to high irradiance levels than the red and brown strains

Minority type matters : ethnic diversity and tolerance in 29 European democracies

Past research has shown that having a large population of ethnic minorities beyond the neighborhood level arouses intolerance in the majority. However, this paper presents the argument that the effect of minority size on tolerance depends on minority type: the less subject the minority is to negative stereotyping, the more favorable the effect that minority size has on tolerance. In this study, a hierarchical linear model was applied to a dataset on advanced and emerging democracies in Europe. The analysis shows that when the duration and level of democracy are controlled for, ethnic tolerance was associated positively with native minority size and negatively with foreign population size.

Prevalence and risk factors for reduced sound tolerance (hyperacusis) in children

OBJECTIVE: To estimate the prevalence of reduced sound tolerance (hyperacusis) in a UK population of 11-year-old children and examine the association of early life and auditory risk factors with report of hyperacusis. DESIGN: A prospective UK population-based study. STUDY SAMPLE: A total of 7097 eleven-year-old children within the Avon longitudinal study of parents and children (ALSPAC) were asked about sound tolerance; hearing and middle-ear function was measured using audiometry, otoacoustic emissions, and tympanometry. Information on neonatal risk factors and socioeconomic factors were obtained through parental questionnaires. RESULTS: 3.7% (95% CI 3.25, 4.14) children reported hyperacusis. Hyperacusis report was less likely in females (adj OR 0.64, 95% CI 0.49, 0.85), and was more likely with higher maternal education level (adj OR 1.72, 95% CI 1.08, 2.72) and with readmission to hospital in first four weeks (adj OR 1.98, 95% CI 1.20, 3.25). Report of hyperacusis was associated with larger amplitude otoacoustic emissions but with no other auditory factors. CONCLUSIONS: The prevalence of hyperacusis in the population of 11-year-old UK children is estimated to be 3.7%. It is more common in boys.

Aluminium tolerance in bean traditional cultivars from Madeira

Common bean (Phaseolus vulgaris L.) is the most important legume crop in the world, providing low-cost, high quality protein, minerals and dietary fiber for human nutrition. The crop was originated from diversity centers in America and exhibits adaptation abilities to different environmental conditions, including soil with low pH. Acid soils occupy 30% of the agro ecosystem areas in the world. In Madeira, acid Andosols and unsatured Cambisols are the dominant groups of soils. Generally, under acidic and infertile conditions, besides of H+ toxicity, soluble aluminium (Al) is the most important abiotic factor limiting plant development and crop productivity. In the field, the hidden roots are also affected and the reduction of root growth under Al stress can be clearly observed in early stages. Seedlings of fifty bean accessions from the Archipelago of Madeira were tested under controlled conditions in the presence of 50 mM Al at pH 4.4. In general, the tested germplasm appeared to be sensitive or very sensitive to Al toxicity. However, fifteen traditional cultivars clearly exhibited elevated Al-tolerance, with an average root relative elongation (RRE) exceeding 50%, while top six accessions surpassed the 60% RRE mark. The Madeira bean germplasm is a valuable resource for sustainable crop production in acid soils and it could be used as parental lines in breeding programs aimed for Al tolerance in common beans.

Screening of wheat Landraces from Madeira Island for iron tolerance

Since the fifteen century, the rainfed-cultivation of wheat for grain is traditionally performed on the Island of Madeira. Under several microclimatic conditions and along very sloppy mountains, the landraces are grown on isolated terraces of Andosols with high amounts of iron. Iron oxides are the main inorganic binding agent contributing to the stability of aggregates and to soil fertility in long-term sustainable agriculture in acid and iron-rich soils. After a two day period of seedling initial growth, a screening test of sixty traditional wheat (Triticum spp.) landraces from the ISOPlexis Genebank at the University of Madeira, Funchal, was performed using nutrient solutions containing 10 or 600 mM Fe, during five days, under controlled laboratory conditions. The elongation of the longest primary root was measured for each genotype and the mean root increment relative to control (as, % relative root increment or RRI; n=28) calculated. This parameter appeared to be a sensitive indicator of Fe tolerance in wheat. Over 85% of wheat germplasm showed the RRI higher than 50%, while the RRI of seven accessions exceeded 70%. This indicates that those landraces are Fe tolerant and might be of particular interest for cultivation under acid rich iron soils of tropical and subtropical areas.

Aluminium tolerance in bean traditional cultivars from Madeira

Common bean (Phaseolus vulgaris L.) is the most important legume crop in the world, providing low-cost, high quality protein, minerals and dietary fiber for human nutrition. The crop was originated from diversity centers in America and exhibits adaptation abilities to different environmental conditions, including soil with low pH. Acid soils occupy 30% of the agro ecosystem areas in the world. In Madeira, acid Andosols and unsatured Cambisols are the dominant groups of soils. Generally, under acidic and infertile conditions, besides of H+ toxicity, soluble aluminium (Al) is the most important abiotic factor limiting plant development and crop productivity. In the field, the hidden roots are also affected and the reduction of root growth under Al stress can be clearly observed in early stages. Seedlings of fifty bean accessions from the Archipelago of Madeira were tested under controlled conditions in the presence of 50 mM Al at pH 4.4. In general, the tested germplasm appeared to be sensitive or very sensitive to Al toxicity. However, fifteen traditional cultivars clearly exhibited elevated Al-tolerance, with an average root relative elongation (RRE) exceeding 50%, while top six accessions surpassed the 60% RRE mark. The Madeira bean germplasm is a valuable resource for sustainable crop production in acid soils and it could be used as parental lines in breeding programs aimed for Al tolerance in common beans.