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The use of manure-based organic soil amendments is common in countries with food animal production. A two-season field study was carried out in central Chile to evaluate the effect of different poultry litter (PL) and pig compost (PC) rates (7.5, 10.0, 12.5, and 15.0 Mg ha−1for each amendment) combined with different nitrogen (N) rates (0, 100, 200, and 300 kg ha−1) on dry matter (DM), grain production, and macronutrient concentration in corn (Zea mays L.) produced during the 2008–2009 (PL) and 2009–2010 (PC) seasons. The soil was clay loam. Organic amendments were applied before sowing, whereas inorganic N (urea) was applied at the 6-leaf stage (V6). When PL was combined with N, DM production ranged between 21.44 and 31.01 Mg ha−1 and grain yield was between 12.76 and 17.86 Mg ha−1. When PC was combined with N, DM production values were between 21.07 and 26.18 Mg ha−1 and grain yield was between 14.01 and 17.14 Mg ha−1. Results indicate that applying a combination of PL and N improved DM production, but applying a combination of PC and N did not affect this parameter. Grain production was only affected by increasing N rates. Applying both PL and N improved plant macronutrient concentration, while only applying PC increased N concentration. These results could be considered as the best recommended practices for using PL and PC. [ABSTRACT FROM AUTHOR]

During the course of the past three years, a new disease of Pinus radiata, referred to as ‘Daño Foliar del Pino’ (DFP) has appeared in the Arauco province of Chile and subsequently spread to other areas. The disease is typified by needle infections, exudation of resin at the bases of the needle brachyblasts and, in younger trees, necrotic lesions in the cambium, which eventually girdle the branches. The disease causes the death of young seedlings and mature trees can also succumb after a few years of successive infection, probably hastened by opportunistic fungi such as Diplodia pinea. Isolations on selective medium for Phytophthora spp. led to the consistent isolation of a Phytophthora sp. from needle tissue. DNA sequence comparisons for the ITS rDNA and cox II gene regions, and morphological observation showed that this oomycete represents a previously undescribed species for which the name Phytophthora pinifolia sp. nov. is provided. This new species is characterized by unbranched sporangiophores, and non-papillate, sub-globose to ovoid sporangia that are occasionally free from the sporangiophore with medium length pedicels. Despite using a number of oospore inducing techniques, oogonia/antheridia were not observed in isolates of P. pinifolia. Pathogenicity trials with P. pinifolia showed that it is pathogenic to P. radiata and causes rapid death of the succulent apical parts of young plants. Phytophthora pinifolia is the first Phytophthora known to be associated with needles and shoots of a Pinus sp. and its aerial habit is well matched with the occurrence and symptoms of DFP in Chile. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this work was to find new sources of resistance to chocolate spot disease, and to validate their stability across different environments. In order to do so, a collection of 307 accessions of Vicia faba was screened for resistance to Botrytis fabae under field conditions; stability of resistance of the 40 most-resistant accessions was tested in a multi-location experiment in Austria, Chile, Egypt, France and Spain over two field seasons. Although complete resistance was not found, nine accessions showed interesting levels of incomplete resistance (ranging from 10 to 20% of average severity across environments, maximum average severity being 47.9%). Genotype×environment interaction accounted for 22% of the sum of squares of the multi-environment evaluation, revealing instability of the phenotypic expression across environments. This usually hampers the efficiency of selection and reduces the adaptability of the plant material. Three accessions stand out for their consistent resistance, both in terms of reduced disease severity and high stability, which make them good candidates for breeding programs. As for environments, those with the highest total severity mean were the most discriminant between accessions. In contrast, those with lower severity means were the most representative of the whole range of environments. It can be concluded that validation of resistance to chocolate spot in different environments is an essential step when screening for material of interest and should be taken into account for further works. [Copyright &y& Elsevier]

Background: Bullying is common in schools and has negative consequences. It can be assessed using a self-reported instrument., Aim: To validate a Spanish self-reporting tool called "Survey of High School Bullying Abuse of Power" (MIAP)., Material and Methods: The instrument has 13 questions, of which 7 are multiple choice, rendering a total of 49 items. It was applied to 2.341 children of seventh and eighth grade attending private, subsidized and municipal schools in the city of Concepción, Chile. Expert judge analysis and estimated reliability using the Cronbach Alpha were used to validate the survey., Results: The instrument obtained a Cronbach Alpha coefficient of 0.8892, classified as good. This analysis generated four scales that explained 30.9% of the variance. They were called "Witness Bullying" with 18 items, accounting for 11.4% of the variance, "Bullying Victim" with 12 items, accounting for 7.5% of the variance, "Bullying Perpetrator and Severe bullying Victim", with 10 items explaining 6.4% of the variance and "Aggressor Bullying" with 6 items accounting for 5.7% of the variance., Conclusions: The MIAP can recognize four basic factors that facilitate the analysis and understanding of bullying, with good levels of reliability and validity. The remaining questions also deliver valuable information.