Water productivity and crop yield in five chickpea varieties – how important is supplemental irrigation?

Chickpea (Cicer arietinum L.) is one of the most important pulse crops in the world as a source of protein for human consumption. In Mediterranean regions, chickpea is traditionally grown as a rainfed crop, thus highly dependent on rainfall. In this situation, supplemental irrigation may be applied. The objective of our study was to evaluate the improvement in crop yield and water productivity with supplemental irrigation in five chickpea varieties (three kabuli type and two desi type) from the Portuguese breeding selection program. Field tests were carried out over two cropping seasons (2009, dry year and 2010, wet year), in Southern Portugal, using four irrigation treatments, full (100%) crop irrigation requirements(IR), 50 % of IR, 25 % of IR and rainfed. A significant increase in grain and shoot biomass yields was observed especially in dry years. Elixir (kabuli type) variety showed the highest grain and biomass yield, harvest index and water productivity. In the dry year, the highest water productivity for grain and biomass production was attained at the 50% and in the wet year in the rainfed treatment

Evaluating chickpea genotypes for abiotic stress tolerance

Being a leguminous crop chickpea (Cicer arietinum L.) is important for the establishment of sustainable and economically viable farming systems. Chickpea is grown and consumed across five continents, making this crop more important in international markets than other food legumes. Adaptation trials of 15 accessions of chickpea, 13 from the ICARDA collection and 2 from the Portuguese national catalogue, took place during two years in two different countries (Portugal, Syria). The trials were conducted under rainfed conditions using a late sowing date to naturally expose the plants to drought and heat stress. The accumulated results indicate a high variability in the yield response among genotypes and regions. In Portugal differences between the most productive accession and the least productive one was higher than 1000 kg/ha in 2009 (drought year) and than 1500Kg/ha in 2010 (rainy year). In general, genotypes that fasten their development cycle showed higher grain yield, especially in drought years. Comparing the two years, we observed three groups of genotypes: i) Stable genotypes, well adapted to distinct environments (like ILC588). ii) Genotypes adapted to adverse conditions, but not responding to favourable conditions (ICL 216); this genotype was also among the best performers under drought conditions in Syria. iii) Genotypes adapted to good conditions, but with bad performance under adverse conditions (ICL 3279). Across the two locations, Portugal and Syria, FLIP03-145C, FLIP87-8C and ILC 588 were on the top 5 during 2009. In 2010, only FLIP87-8C standout to be among the best performers under drought conditions in both countries

Ocean-atmosphere exchange of organic carbon and CO2 surrounding the Antarctic Peninsula

Exchangeable organic carbon (OC) dynamics and CO2 fluxes in the Antarctic Peninsula during austral summer were highly variable, but the region appeared to be a net sink for OC and nearly in balance for CO2. Surface exchangeable dissolved organic carbon (EDOC) measurements had a 43±3 (standard error, hereafter SE) μmol CL-1 overall mean and represented around 66% of surface non-purgeable dissolved organic carbon (DOC) in Antarctic waters, while the mean concentration of the gaseous fraction of organic carbon (GOCH′-1) was 46±3 SE μmol C L -1. There was a tendency towards low fugacity of dissolved CO 2 (fCO2-w) in waters with high chlorophyll a (Chl a) content and high fCO2-w in areas with high krill densities. However, such relationships were not found for EDOC. The depth profiles of EDOC were also quite variable and occasionally followed Chl a profiles. The diel cycles of EDOC showed two distinct peaks, in the middle of the day and the middle of the short austral dark period, concurrent with solar radiation maxima and krill night migration patterns. However, no evident diel pattern for GOC H′-1 or CO2 was observed. The pool of exchangeable OC is an important and active compartment of the carbon budget surrounding the Antarctic Peninsula and adds to previous studies highlighting its importance in the redistribution of carbon in marine environments. © Author(s) 2014.This is a contribution of both Aportes Atmosféricos de Carbono Orgánico y Contaminanates al océano Polar (ATOS) and the Spanish component of the Synoptic Antarctic Shelf-Slope Interactions study (ESASSI), funded by the Spanish Ministry of Science under the scope of the International Polar Year (IPY). Maria Ll. Calleja was funded by the Spanish Research Council (CSIC, grant JAEDOC030) and cofounded by the Fondo Social Europeo (FSO)Peer Reviewe

Long-term tobacco exposure and immunosenescence: paradoxical effects on T-cells telomere length and telomerase activity

Immunosenescence are alterations on immune system that occurs throughout an individual life. The main characteristic of this process is replicative senescence, evaluated by telomere shortening. Several factors implicate on telomere shortening, such as smoking. In this study, we evaluated the influence of smoking and Chronic Obstructive Pulmonary Disease (COPD) on cytokines, telomere length and telomerase activity. Blood samples were collected from subjects aged over 60 years old: Healthy (never smokers), Smokers (smoking for over 30 years) and COPDs (ex-smokers for ≥15 years). A young group was included as control. PBMCs were cultured for assessment of telomerase activity using RT-PCR, and cytokines secretion flow cytometry. CD4+ and CD8+ purified lymphocytes were used to assess telomere length using FlowFISH. We observed that COPD patients have accelerated telomere shortening. Paradoxically, smokers without lung damage showed preserved telomere length, suggesting that tobacco smoking may affect regulatory mechanisms, such as telomerase. Telomerase activity showed diminished activity in COPDs, while Smokers showed increased activity compared to COPDs and Healthy groups. Extracellular environment reflected this unbalance, indicated by an anti-inflammatory profile in Smokers, while COPDs showed an inflammatory prone profile. Further studies focusing on telomeric maintenance may unveil mechanisms that are associated with cancer under long-term smoking

High summer temperatures amplify functional differences between coral- and algae-dominated reef communities

Shifts from coral to algal dominance are expected to increase in tropical coral reefs as a result of anthropogenic disturbances. The consequences for key ecosystem functions such as primary productivity, calcification, and nutrient recycling are poorly understood, particularly under changing environmental conditions. We used a novel in situ incubation approach to compare functions of coral- and algae-dominated communities in the central Red Sea bimonthly over an entire year. In situ gross and net community primary productivity, calcification, dissolved organic carbon fluxes, dissolved inorganic nitrogen fluxes, and their respective activation energies were quantified to describe the effects of seasonal changes. Overall, coral-dominated communities exhibited 30% lower net productivity and 10 times higher calcification than algae-dominated communities. Estimated activation energies indicated a higher thermal sensitivity of coral-dominated communities. In these communities, net productivity and calcification were negatively correlated with temperature (>40% and >65% reduction, respectively, with +5 degrees C increase from winter to summer), whereas carbon losses via respiration and dissolved organic carbon release more than doubled at higher temperatures. In contrast, algae-dominated communities doubled net productivity in summer, while calcification and dissolved organic carbon fluxes were unaffected. These results suggest pronounced changes in community functioning associated with coral-algal phase shifts. Algae-dominated communities may outcompete coral-dominated communities because of their higher productivity and carbon retention to support fast biomass accumulation while compromising the formation of important reef framework structures. Higher temperatures likely amplify these functional differences, indicating a high vulnerability of ecosystem functions of coral-dominated communities to temperatures even below coral bleaching thresholds. Our results suggest that ocean warming may not only cause but also amplify coral-algal phase shifts in coral reefs.Peer reviewe

Nutrient pollution enhances productivity and framework dissolution in algae- but not in coral-dominated reef communities

Ecosystem services provided by coral reefs may be susceptible to the combined effects of benthic species shifts and anthropogenic nutrient pollution, but related field studies are scarce. We thus investigated in situ how dissolved inorganic nutrient enrichment, maintained for two months, affected community-wide biogeochemical functions of intact coral- and degraded algae-dominated reef patches in the central Red Sea. Results from benthic chamber incubations revealed 87% increased gross productivity and a shift from net calcification to dissolution in algae-dominated communities after nutrient enrichment, but the same processes were unaffected by nutrients in neighboring coral communities. Both community types changed from net dissolved organic nitrogen sinks to sources, but the increase in net release was 56% higher in algae-dominated communities. Nutrient pollution may, thus, amplify the effects of community shifts on key ecosystem services of coral reefs, possibly leading to a loss of structurally complex habitats with carbonate dissolution and altered nutrient recycling.Peer reviewe

Scaling properties of protein family phylogenies

One of the classical questions in evolutionary biology is how evolutionary processes are coupled at the gene and species level. With this motivation, we compare the topological properties (mainly the depth scaling, as a characterization of balance) of a large set of protein phylogenies with a set of species phylogenies. The comparative analysis shows that both sets of phylogenies share remarkably similar scaling behavior, suggesting the universality of branching rules and of the evolutionary processes that drive biological diversification from gene to species level. In order to explain such generality, we propose a simple model which allows us to estimate the proportion of evolvability/robustness needed to approximate the scaling behavior observed in the phylogenies, highlighting the relevance of the robustness of a biological system (species or protein) in the scaling properties of the phylogenetic trees. Thus, the rules that govern the incapability of a biological system to diversify are equally relevant both at the gene and at the species level.Comment: Replaced with final published versio

Nutrient pollution enhances productivity and framework dissolution in algae- but not in coral-dominated reef communities

Ecosystem services provided by coral reefs may be susceptible to the combined effects of benthic species shifts and anthropogenic nutrient pollution, but related field studies are scarce. We thus investigated in situ how dissolved inorganic nutrient enrichment, maintained for two months, affected community-wide biogeochemical functions of intact coral- and degraded algae-dominated reef patches in the central Red Sea. Results from benthic chamber incubations revealed 87% increased gross productivity and a shift from net calcification to dissolution in algae-dominated communities after nutrient enrichment, but the same processes were unaffected by nutrients in neighboring coral communities. Both community types changed from net dissolved organic nitrogen sinks to sources, but the increase in net release was 56% higher in algae-dominated communities. Nutrient pollution may, thus, amplify the effects of community shifts on key ecosystem services of coral reefs, possibly leading to a loss of structurally complex habitats with carbonate dissolution and altered nutrient recycling.This work was supported by KAUST baseline funding to BHJ and by grant Wi 2677/9-1 from the German Research Foundation (DFG) to C

Universal scaling in the branching of the Tree of Life

Understanding the patterns and processes of diversification of life in the planet is a key challenge of science. The Tree of Life represents such diversification processes through the evolutionary relationships among the different taxa, and can be extended down to intra-specific relationships. Here we examine the topological properties of a large set of interspecific and intraspecific phylogenies and show that the branching patterns follow allometric rules conserved across the different levels in the Tree of Life, all significantly departing from those expected from the standard null models. The finding of non-random universal patterns of phylogenetic differentiation suggests that similar evolutionary forces drive diversification across the broad range of scales, from macro-evolutionary to micro-evolutionary processes, shaping the diversity of life on the planet.Comment: 6 pages + 19 of Supporting Informatio