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Gonzalez-Toril E.,CSIC - National Institute of Aerospace Technology | Santofimia E.,Instituto Geologico Y Minero Of Espana | Blanco Y.,CSIC - National Institute of Aerospace Technology | Lopez-Pamo E.,Instituto Geologico Y Minero Of Espana | And 5 more authors.
Microbial Ecology | Year: 2015

The exposure of fresh sulfide-rich lithologies by the retracement of the Nevado Pastoruri glacier (Central Andes, Perú) is increasing the presence of heavy metals in the water as well as decreasing the pH, producing an acid rock drainage (ARD) process in the area. We describe the microbial communities of an extreme ARD site in Huascarán National Park as well as their correlation with the water physicochemistry. Microbial biodiversity was analyzed by FLX 454 sequencing of the 16S rRNA gene. The suggested geomicrobiological model of the area distinguishes three different zones. The proglacial zone is located in the upper part of the valley, where the ARD process is not evident yet. Most of the OTUs detected in this area were related to sequences associated with cold environments (i.e., psychrotolerant species of Cyanobacteria or Bacteroidetes). After the proglacial area, an ARD-influenced zone appeared, characterized by the presence of phylotypes related to acidophiles (Acidiphilium) as well as other species related to acidic and cold environments (i.e., acidophilic species of Chloroflexi, Clostridium and Verrumicrobia). Sulfur- and iron-oxidizing acidophilic bacteria (Acidithiobacillus) were also identified. The post-ARD area was characterized by the presence of OTUs related to microorganisms detected in soils, permafrost, high mountain environments, and deglaciation areas (Sphingomonadales, Caulobacter or Comamonadaceae). © 2015, Springer Science+Business Media New York. Source

The presence of heavy metals in cocoa's crop is becoming a difficulty for farmers and cooperatives at Huanuco and Ucayali regions, Peru. In this research cadmium and lead content in cocoa's soils and leaves was evaluated. For it, soil and foliar samples were collected in 22 organic crop plots located at Huánuco (17) and Ucayali (5) region. Pearson's correlation analysis was realized between content of lead and cadmium available in soils with foliar variables (P, Mg, Ca, Zn, Cd, Pb) and soil (Sand, Clay and K). According to the soil analysis only the potassium was deficient; while in leaf tissue deficiencies of N, P, K, Mg and Zn were observed. The average values of cadmium and lead available in soils were 0.53 ppm and 3.02 ppm and in foliar were 0.21 ppm and 0.58 ppm respectively. Source

Juarez J.D.,University of Murcia | Juarez J.D.,National University of Agriculture of La Selva | Parrilla I.,University of Murcia | Vazquez J.M.,University of Murcia | And 2 more authors.
Reproduction, Fertility and Development | Year: 2011

Two experiments were performed in the present study that demonstrated that boar spermatozoa are capable of surviving rapid cooling rates within a range of 15-5°C before freezing. Boar ejaculates diluted in Beltsville thawing solution (BTS) (1:1, v/v) were held at 17-20°C and shipped over a 24-h time period from two AI centres to a cryobiology laboratory, where they were pooled (Experiment 1) or cryopreserved individually (Experiment 2) using a standard 0.5-mL straw freezing protocol. The effects of cooling before freezing were assessed after thawing through the objective evaluation of sperm motility and flow cytometric analysis of membrane integrity, acrosomal status, changes in membrane lipid architecture monitored by merocyanine and annexin V binding and intracellular production of reactive oxygen species. In Experiment 1 (six replicates), two semen pools (five ejaculates per pool) were cooled from 15 to 5°C at rates of 0.08, 0.13, 0.40 and 1.50°Cmin-1. These cooling rates did not result in any significant differences (P>0.05) in any of the post-thaw sperm assessments, even in thawed samples incubated under capacitation conditions. In Experiment 2, three individual ejaculates from 16 boars were slowly (0.08°Cmin-1) or rapidly (1.5°Cmin-1) cooled before freezing. A consistent interboar variability (P<0.01) was detected, which was independent of the cooling rate used. Cooling rate only significantly influenced (P<0.05) sperm assessments in four of 16 boars, which exhibited slightly higher percentages of motile cells and intact plasma and acrosomal membranes in the samples that had been cooled slowly. These findings demonstrate that boar spermatozoa undergoing cryopreservation can withstand rapid cooling rates before freezing. © 2011 CSIRO. Source

Kieck J.S.,University of Hamburg | Zug K.L.M.,University of Hamburg | Huamani Yupanqui H.A.,National University of Agriculture of La Selva | Gomez Aliaga R.,United Nations Office on Drugs and Crime | Cierjacks A.,University of Hamburg
Agriculture, Ecosystems and Environment | Year: 2016

Biodiversity may be positively related to crop yield, but the mechanisms by which such effects are realized are as yet poorly understood. Reduced pest incidence may be one cause. To better predict the quality and strength of biodiversity effects in cacao agroforestry systems and to disentangle potential drivers, we analyzed relationships of plant diversity with crop quantity (yield, fruit set, fruit size), pathogen incidence (Moniliophthora perniciosa, Moniliophthora roreri, Phytophthora spp.), and with the profile of selected secondary compounds (methylxanthines and polyphenols) in seeds of 48 cacao trees cultivated on 14 farms in Peruvian Amazonia. Our results revealed no correlation of yield per hectare or total fruit set with plant alpha diversity measures on the studied cacao farms. However, the number and size of ripe fruits without fungal infestation increased at higher diversity of the herb and shrub layer and at lower diversity and smaller basal area of shade trees. Greater diversity in the herb and shrub layer reduced the incidence of the Phytophthora pathogen but increased the incidence of M. roreri. At higher alpha diversity in the understory, contents of caffeine, theobromine, and catechin hydrate in cacao seeds significantly increased. The changes in plant secondary compounds showed inconsistent relations with the infestation rates of fungal pathogens. While trees infested with M. perniciosa showed higher contents of polyphenols and caffeine in seeds, cacao trees with higher caffeine content in seeds were less likely to be affected by Phytophthora. Similarly, a higher epicatechin content in seeds was associated with reduced M. roreri incidence. Our data provide evidence for a tight interplay of biodiversity, pathogen incidence, and the crop's secondary metabolism on cacao farms. Overall, considering biochemical traits in yield-diversity relationships allowed for a better understanding of the contribution of biotic interactions to biodiversity effects in tropical agroforestry systems. © 2016 Elsevier B.V. Source

Aspilcueta-Borquis R.R.,Sao Paulo State University | Sesana R.C.,Sao Paulo State University | Berrocal M.H.M.,National University of Agriculture of La Selva | Seno L.D.O.,Sao Paulo State University | And 5 more authors.
Genetics and Molecular Biology | Year: 2010

The objective of the present study was to estimate genetic parameters for test-day milk, fat and protein yields and 305-day-yields in Murrah buffaloes. 4,757 complete lactations of Murrah buffaloes were analyzed. Co-variance components were estimated by the restricted maximum likelihood method. The models included additive direct genetic and permanent environmental effects as random effects, and the fixed effects of contemporary group, milking number and age of the cow at calving as linear and quadratic covariables. Contemporary groups were defined by herd-year-month of test for test-day yields and by herd-year-season of calving for 305-day yields. The heritability estimates obtained by two-trait analysis ranged from 0.15 to 0.24 for milk, 0.16 to 0.23 for protein and 0.13 to 0.22 for fat, yields. Genetic and phenotypic correlations were all positive. The observed population additive genetic variation indicated that selection might be an effective tool in changing population means in milk, fat and protein yields. Copyright © 2009, Sociedade Brasileira de Genética. Source

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