Investigations on herbicide resistance in European silky bent grass (Apera spica-venti) populations

Journal of Plant Diseases and Protection - In this study, the results of two-year investigations on herbicide resistance in silky bent grass (Apera spica-venti) populations are presented....     

Durable resistance to the wheat rusts: integrating systems biology and traditional phenotype-based research methods to guide the deployment of resistance genes

Genes which confer partial resistance to the rusts in wheat figure prominently in discussions of potential durable resistance strategies. The positional cloning of the first of these genes, Lr34/Yr18 and Yr36, has revealed different protein structures, suggesting that the category of partial resistance genes, as defined by phenotype, likely groups together suites of functionally heterogenous genes. With the number of mapped partial rust resistance genes increasing rapidly as a result of ongoing advances in marker and sequencing technologies, breeding programs needing to select and prioritize genes for deployment confront a fundamental question: which genes or gene combinations are more likely to provide durable protection against these evolving pathogens? We argue that a refined classification of partial rust resistance genes is required to start answering this question, one based not merely on disease phenotype but also on gene cloning, molecular functional characterization, and interactions with other host and pathogen proteins. Combined with accurate and detailed disease phenotyping and standard genetic studies, an integrated wheat-rust interactome promises to provide the basis for a functional classification of partial resistance genes and thus a conceptual framework for their rational deployment.     

Growth responses of West-Mediterranean Pinus nigra to climate change are modulated by competition and productivity: Past trends and future perspectives

Positive and negative effects of climate change on forest growth have been observed in different parts of the world. However, much is still unknown about how forest structure and productivity might affect climate-growth relationships in the future. We examined the effects of climate, site quality, and competition on tree basal area growth of black pine (Pinus nigra Arn.) between 1964 and 2005 in 21 sites in the Iberian Peninsula. We used a new approach to simultaneously account for climate-growth relationships, inter-annual growth variability, and stand structural changes, by fitting a linear mixed effects model (LMEM) for basal area increments (BAI) using climate data, tree-ring chronologies, and repeated forest inventory data. This approach showed the potential to improve our understanding of climate effects on tree growth and to include climate in empirical forest growth models. We used the LMEM to make projections of BAI growth under two CO₂ emission scenarios and two global circulation models (GCM). The main climate drivers for growth were precipitation from previous autumn to summer and winter temperature with a positive effect, and temperature in spring-summer which had a negative effect. Tree response to climate was modulated by stand conditions, tree competition, and productivity. The more productive stands showed greater ability to either maintain or increase growth at warmer spring-summer temperatures under different levels of autumn-summer precipitation. Growth projections showed important regional differences. In general, growth under future climate is predicted to decrease although moderate growth increases might be expected in the northern region for highly and moderately productive stands.     

An acute case of intoxication with cyanobacteria and cyanotoxins in recreational water in Salto Grande Dam, Argentina

Cyanobacterial blooms and hepatotoxic microcystins (MCs) usually occur in summer, constituting a sanitary and environmental problem in Salto Grande Dam, Argentina. Water sports and recreational activities take place in summer in this lake. We reported an acute case of cyanobacterial poisoning in Salto Grande dam, Argentina, which occurred in January 2007. Accidentally, a young man was immersed in an intense bloom of Microcystis spp. A level of 48.6 μg·L(-1) of microcystin-LR was detected in water samples. Four hours after exposure, the patient showed nausea, abdominal pain and fever. Three days later, dyspnea and respiratory distress were reported. The patient was hospitalized in intensive care and diagnosed with an atypical pneumonia. Finally, a week after the exposure, the patient developed a hepatotoxicosis with a significant increase of hepatic damage biomarkers (ALT, AST and γGT). Complete recovery took place within 20 days. This is the first study to show an acute intoxication with microcystin-producing cyanobacteria blooms in recreational water.     

Monilinia species identified on peach and nectarine in Croatia,with the first record of Monilinia fructicola

During 2012, an official survey was conducted for Monilinia species present on peach and nectarine in Croatia. In total, 169 Monilinia spp. isolates were collected from 24 commercial orchards and identified according to morphology in culture and PCR. Eighty of the isolates were identified as Monilinia laxa, 70 as M. fructigena and 19 as M. fructicola. M. fructicola was found only at one location in the Mediterranean part of the country, and this is the first record of this quarantine fungus in Croatia. PCR diagnostic tests using M. fructicola‐specific primer pair MO368‐5/MO368‐10R repeatedly gave false negatives for some isolates. PCR tests using primer pair ITS1‐Mfc1/ITS4‐Mfc1 amplified M. fructicola‐specific product in all isolates and was therefore shown to be more suitable for diagnostic purposes.     

Brucellosis: a short review of the disease situation in Paraguay

A short review of the brucellosis situation, its control and eradication programs are presented. Data from over 1.2 milliom samples collected from more than 50,718 groups of cattle over a period of over 20 years (1979–2000) illustrates that over the last few years the number of individual reactors remain constant at around 3–4%. The percentage of reactive groups of animals decreased over these years, reflecting a better disease management and possibly an improved general education, handling of information on the immune (vaccination) status of animals and testing practices. Reported zoonotic cases are presented, as well as control and eradication programs, including utilization of vaccines.