121 research outputs found

    Benefit-cost analysis of participatory breeding program in Syria

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    Participatory plant breeding is seen by several scientists as a way to overcome the limitations of conventional breeding by offering farmers the possibility of deciding which varieties better suit their needs and conditions without exposing them to any risk. It exploits the potential gains of breeding for specific adaptation through the selection in the marginal environment. The participation of farmers increases the probability and speed of adoption as well as the breeding efficiency and the effectiveness of the breeding program. The objective of this study is to estimate and compare the benefits and costs of participatory and conventional barley breeding programs. Benefit-cost analysis was used to analyze the costs and benefits of the PPB program at ICARDA and the conventional program at ICARDA and NARS

    Decentralized participatory plant breeding: a case from Syria

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    Conventional modern plant breeding has been recognized to be more beneficial to farmers in high potential environments or those who could profitably modify their environment to suit new cultivars, than to the poorest farmers who could not afford to make the necessary modifications. As a consequence, low yields, crop failures, malnutrition and poverty affect a large proportion of humanity

    Decentralized participatory plant breeding

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    It is widely recognized that conventional plant breeding has been more beneficial to farmers in high potential environments or those who could profitably modify their environment to suit new cultivars, than to the poorest farmers who could not afford to modify their environment through the application of additional inputs and could not risk the replacement of their traditional, well-known and reliable varieties. As a consequence, low yields, crop failures, malnutrition, famine, and eventually poverty are still affecting a large proportion of humanity. Participatory plant breeding is seen by several scientists as a way to overcome the limitations of conventional breeding by offering farmers the possibility of deciding which varieties better suit their needs and conditions without exposing the household to any risk. Participatory plant breeding exploits the potential gains of breeding for specific adaptation through decentralized selection, defined as selection in the target environment, and is the ultimate conceptual consequence of a positive interpretation of genotype x environment interactions. This article describes a model of participatory plant breeding in which genetic variability is generated by professional breeders, selection is conducted jointly by breeders, extension specialists and farmers in a number of target environments, and the best selections are used by breeders in further cycles of recombination. Farmers handle the first phases of seed multiplication of promising breeding material in village-based seed production systems. The model has the following advantages: (i) varieties reach the release phase earlier than in conventional breeding; (ii) the release and seed multiplication concentrate on varieties known to be acceptable by farmers; (iii) it increases biodiversity because different varieties are selected in different locations; (iv) varieties fit to the agronomic management that farmers are familiar with and can afford and therefore can be beneficial to poor farmers. These advantages are particularly relevant to developing countries where large investments in plant breeding have not resulted in production increases, especially in marginal environments

    Decentralized Participatory Plant Breeding

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    This report, presented by Dr. Salvatore Ceccarelli from ICARDA, describes a model of participatory plant breeding in which genetic variability is generated by professional breeders, selection is conducted jointly by breeders, extension specialists and farmers in a number of target environments, and the best selections are used by breeders in further cycles of recombination. Farmers handle the first phases of seed multiplication of promising breeding material in village-based seed production systems. The model has the following advantages: (i) varieties reach the release phase earlier than in conventional breeding; (ii) the release and seed multiplication concentrate on varieties known to be acceptable by farmers; (iii) it increases biodiversity because different varieties are selected in different locations; (iv) varieties fit to the agronomic management that farmers are familiar with and can afford and therefore can be beneficial to poor farmers. These advantages are particularly relevant to developing countries where large investments in plant breeding have not resulted in production increases, especially in marginal environments. This report was discussed at the Stakeholder Meeting at AGM2005

    A user-friendly database for Participatory Plant Breeding programs

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    In a decentralized and participatory plant breeding (PPB) program, in contrast to conventional plant breeding, farmers select from a large number of genotypes over a number of cycles in several locations. As selection is for location-specific adaptation a PPB program based on, for example, four stages of selection, generates large, unbalanced data sets. With common spreadsheet software it is not possible, or it is at least very cumbersome to extract all the information, particularly the one that is related to genotype x environment (GE) interactions. Therefore, there is a need for an information system that makes it as easy as possible to retrieve and compare data over all given factors in the PPB-program. Due to a lack of education and financial resources in developing countries, the use of existing databases was not an option because of their complexity and/or price. We have built a simple, free and user-friendly database that allows to store, retrieve and analyze the plant breeding data. The database is implemented using the Java based HyperSQL Database Engine (HSQLDB) in the package of Open Office with links to the input formats of Genstat and GGEbiPlot. The proposed database is capable of managing the following data in a PPBprogram for barley: (I) trial data for any trial or field design (II) field data for any given trait (III) results from statistical analyses (IV) farmers selection individually or in groups

    Voriconazole treatment of Candida tropicalis meningitis: persistence of (1,3)-b-D-glucan in the cerebrospinal fluid is a marker of clinical and microbiological failure

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    Introduction: Infections are still the most common complications of cerebral shunt procedures. Even though fungal etiologies are considered to be rare, they are associated with significant morbidity and mortality. Due to their uncommonness, diagnostic procedures and optimal therapy are poorly defined. We report a case of Candida tropicalis infection of ventriculo-peritoneal cerebrospinal fluid (CSF) shunt in a 49-year-old immune competent male treated with voriconazole (VOR). Methods: Microbiological and CSF markers (1,3-b-D-glucan-BDG) of fungal infection, biofilm production capacity, sensitivity of serial isolates of the pathogen, and the concentration of the antifungal drug have been monitored and related to the clinical course of this infection. Results: Despite appropriate treatment with VOR, in terms of adequate achieved CSF drug concentrations and initial effective therapeutic response, loss of VOR susceptibility of the C tropicalis and treatment failure were observed. Conclusion: Biofilm production of the C. tropicalis isolate might have had a significant role in treatment failure. Of interest, clinical and microbiological unfavorable outcome was anticipated by persistence of BDG in CSF. Rising titers of this marker were associated with relapse of fungal infection

    In Vitro Reduced Susceptibility to Pentavalent Antimonials of a Leishmania infantum Isolate from a Human Cutaneous Leishmaniasis Case in Central Italy

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    Cutaneous leishmaniasis (CL) caused by Leishmania (Leishmania) infantum is endemic in the Mediterranean basin. Here we report an autochthonous case of CL in a patient living in central Italy with an unsatisfactory response to treatment with intralesional Meglumine Antimoniate and in vitro demonstration of reduced susceptibility to SbIII. Parasitological diagnosis was first achieved by histopathology on tissue biopsy and the patient was treated with a local infiltration of Meglumine Antimoniate. Since the clinical response at 12 weeks from the treatment’s onset was deemed unsatisfactory, two further skin biopsies were taken for histopathological examination, DNA extraction and parasite isolation. L. (L.) infantum was identified by molecular typing. The low susceptibility to Meglumine Antimoniate was confirmed in vitro: the promastigotes from the patient strain showed significantly lower susceptibility to SbIII (the active trivalent form of antimonial) compared to the reference strain MHOM/TN/80/IPT1. The patient underwent a new treatment course with intravenous liposomal Amphotericin B, reaching complete healing of the lesion. Additional studies are needed to confirm the epidemiological and clinical relevance of reduced susceptibility to SbIII of human L. (L.) infantum isolate in Italy

    LPS-induced TNF-α factor mediates pro-inflammatory and pro-fibrogenic pattern in non-alcoholic fatty liver disease

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    Lipopolysaccharide (LPS) is currently considered one of the major players in non-alcoholic fatty liver disease (NAFLD) pathogenesis and progression. Here, we aim to investigate the possible role of LPS-induced TNF-α factor (LITAF) in inducing a pro-inflammatory and pro-fibrogenic phenotype of non-alcoholic steatohepatitis (NASH).We found that children with NAFLD displayed, in different liver-resident cells, an increased expression of LITAF which correlated with histological traits of hepatic inflammation and fibrosis. Total and nuclear LITAF expression increased in mouse and human hepatic stellate cells (HSCs). Moreover, LPS induced LITAF-dependent transcription of IL-1β, IL-6 and TNF-α in the clonal myofibroblastic HSC LX-2 cell line, and this effect was hampered by LITAF silencing. We showed, for the first time in HSCs, that LITAF recruitment to these cytokine promoters is LPS dependent. However, preventing LITAF nuclear translocation by p38MAPK inhibitor, the expression of IL-6 and TNF-α was significantly reduced with the aid of p65NF-ĸB, while IL-1β transcription exclusively required LITAF expression/activity. Finally, IL-1β levels in plasma mirrored those in the liver and correlated with LPS levels and LITAF-positive HSCs in children with NASH.In conclusion, a more severe histological profile in paediatric NAFLD is associated with LITAF over-expression in HSCs, which in turn correlates with hepatic and circulating IL-1β levels outlining a panel of potential biomarkers of NASH-related liver damage. The in vitro study highlights the role of LITAF as a key regulator of the LPS-induced pro-inflammatory pattern in HSCs and suggests p38MAPK inhibitors as a possible therapeutic approach against hepatic inflammation in NASH

    Differentially expressed genes between drought-tolerant and drought-sensitive barley genotypes in response to drought stress during the reproductive stage

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    Drought tolerance is a key trait for increasing and stabilizing barley productivity in dry areas worldwide. Identification of the genes responsible for drought tolerance in barley (Hordeum vulgare L.) will facilitate understanding of the molecular mechanisms of drought tolerance, and also facilitate the genetic improvement of barley through marker-assisted selection or gene transformation. To monitor the changes in gene expression at the transcriptional level in barley leaves during the reproductive stage under drought conditions, the 22K Affymetrix Barley 1 microarray was used to screen two drought-tolerant barley genotypes, Martin and Hordeum spontaneum 41-1 (HS41-1), and one drought-sensitive genotype Moroc9-75. Seventeen genes were expressed exclusively in the two drought-tolerant genotypes under drought stress, and their encoded proteins may play significant roles in enhancing drought tolerance through controlling stomatal closure via carbon metabolism (NADP malic enzyme, NADP-ME, and pyruvate dehydrogenase, PDH), synthesizing the osmoprotectant glycine-betaine (C-4 sterol methyl oxidase, CSMO), generating protectants against reactive-oxygen-species scavenging (aldehyde dehydrogenase,ALDH, ascorbate-dependent oxidoreductase, ADOR), and stabilizing membranes and proteins (heat-shock protein 17.8, HSP17.8, and dehydrin 3, DHN3). Moreover, 17 genes were abundantly expressed in Martin and HS41-1 compared with Moroc9-75 under both drought and control conditions. These genes were possibly constitutively expressed in drought-tolerant genotypes. Among them, seven known annotated genes might enhance drought tolerance through signalling [such as calcium-dependent protein kinase (CDPK) and membrane steroid binding protein (MSBP)], anti-senescence (G2 pea dark accumulated protein, GDA2), and detoxification (glutathione S-transferase, GST) pathways. In addition, 18 genes, including those encoding Δl-pyrroline-5-carboxylate synthetase (P5CS), protein phosphatase 2C-like protein (PP2C), and several chaperones, were differentially expressed in all genotypes under drought; thus they were more likely to be general drought-responsive genes in barley. These results could provide new insights into further understanding of drought-tolerance mechanisms in barley
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