A better understanding of the genetic and ecological factors underlying successful invasions is critical to mitigate the negative impacts of invasive species. Here, we study the invasion history of Helianthus annuus populations from Argentina, with particular emphasis on the role of post-introduction admixture with cultivated sunflower (also H. annuus) and climate adaptation driven by large haploblocks.
View Article and Find Full Text PDFWeedy rice, a pervasive and troublesome weed found across the globe, has often evolved through fertilization of rice cultivars with little importance of crop-weed gene flow. In Argentina, weedy rice has been reported as an important constraint since the early 1970s, and, in the last few years, strains with herbicide-resistance are suspected to evolve. Despite their importance, the origin and genetic composition of Argentinian weedy rice as well its adaptation to agricultural environments has not been explored so far.
View Article and Find Full Text PDFPremise: The phenotype of hybrids between a crop and its wild or weed counterpart is usually intermediate and maladapted compared to that of their parents; however, hybridization has sometimes been associated with increased fitness, potentially leading to enhanced weediness and invasiveness. Since the ecological context and maternal genetic effects may affect hybrid fitness, they could influence the evolutionary outcomes of hybridization. Here, we evaluated the performance of first-generation crop-weed hybrids of Raphanus sativus and their parents in two contrasting ecological conditions.
View Article and Find Full Text PDFAgricultural weeds descended from domesticated ancestors, directly from crops (endoferality) and/or from crop-wild hybridization (exoferality), may have evolutionary advantages by rapidly acquiring traits pre-adapted to agricultural habitats. Understanding the role of crops on the origin and evolution of agricultural weeds is essential to develop more effective weed management programs, minimize crop losses due to weeds, and accurately assess the risks of cultivated genes escaping. In this review, we first describe relevant traits of weediness: shattering, seed dormancy, branching, early flowering and rapid growth, and their role in the feralization process.
View Article and Find Full Text PDFHybridization between crops and their wild relatives may promote the evolution of de-domesticated (feral) weeds. Wild sunflower (Helianthus annuus L.) is typically found in ruderal environments, but crop-wild hybridization may facilitate the evolution of weedy populations.
View Article and Find Full Text PDFWhen cultivated and wild plants hybridize, hybrids often show intermediate phenotypic traits relative to their parents, which makes them unfit in natural environments. However, maternal genetic effects may affect the outcome of hybridization by controlling expression of the earliest life history traits. Here, using wild, cultivated and reciprocal crop-wild sunflower (Helianthus annuus L.
View Article and Find Full Text PDFExposure to occupational aerosols are a known hazard in many industry sectors and can be a risk factor for several respiratory diseases. In this study, a laboratory evaluation of low-cost aerosol sensors, the Dylos DC1700 and a modified Dylos known as the Utah Modified Dylos Sensor (UMDS), was performed to assess the sensors' efficiency in sampling respirable and inhalable dust at high concentrations, which are most common in occupational settings. Dust concentrations were measured in a low-speed wind tunnel with 3 UMDSs, collocated with an aerosol spectrometer (Grimm 1.
View Article and Find Full Text PDFBackground: Feral radish (Raphanus sativus L.) is a problematic weed that has become resistant to acetohydroxyacid synthase (AHAS) inhibitor herbicides due to the Trp574Leu mutation. An AHAS gene mutation that causes herbicide resistance may have negative pleiotropic effects on plant fitness.
View Article and Find Full Text PDFThe movement computerized analysis of upper limb is a valid support in the definition of residual functional capability and of specific work suitability in complex cases. This methodology of evaluation is able to correctly and objectively define the tridimensional ranges of motion of every patient's upper limb. This fact can be particularly useful for workers coming back to work after a work-related or a not work-related accident of for handicapped workers at the beginning of a new work activity.
View Article and Find Full Text PDFG Ital Med Lav Ergon
October 2005
As reported by previous literature, the prevalence of musculoskeletal disorders is high in population of local police officers, due to several risk factors, including awkward posture, jolt/vibrations and stress. The results of our study reveal that the most common musculoskeletal symptoms among local police officers are cervicobrachial pain, low back pain and sciatica. Low-back pain is associated with tasks exposing to awkward posture of the spine (traffic policemen and policemen involved in office-based duties); cervical and upper extremity disorders are related to the exposure to vibrations and to the upper limb posture held by motorcycle police.
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