125 research outputs found
Natural selection on plant resistance to herbivores in the native and introduced range
. When plants are introduced into new regions, the absence of their co-evolved natural enemies can result
in lower levels of attack. As a consequence of this reduction in enemy pressure, plant performance may increase and
selection for resistance to enemies may decrease. In the present study, we compared leaf damage, plant size and leaf
trichome density, as well as the direction and magnitude of selection on resistance and plant size between non-native
(Spain) and native (Mexico) populations of Datura stramonium. This species was introduced to Spain about five centuries
ago and constitutes an ideal system to test four predictions of the enemy release hypothesis. Compared with
native populations, we expected Spanish populations of D. stramonium to have (i) lower levels of foliar damage; (ii)
larger plant size; (iii) lower leaf trichome density that is unrelated to foliar damage by herbivores; and (iv) weak or
no selection on resistance to herbivores but strong selection on plant size. Our results showed that, on average, plants
from non-native populations were significantly less damaged by herbivores, were less pubescent and were larger than
those from native populations. We also detected different selection regimes on resistance and plant size between the
non-native and native ranges. Positive selection on plant size was detected in both ranges (though it was higher in the
non-native area), but consistent positive selection on relative resistance was detected only in the native range. Overall,
we suggest that changes in selection pressure on resistance and plant size in D. stramonium in Spain are a
consequence of ‘release from natural enemies’
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The “Mera” lahar deposit in the upper Amazon basin: Transformation of a late Pleistocene collapse at Huisla volcano, central Ecuador
Over the last years, project work in teams has become commonplace in organizations. Studies have indicated that the motivational climate in which teams operate is highly relevant in determining employee behavior. This study investigates the effect of motivational climates, as defined by goal setting theory, on collaboration in project teams. In a survey among 173 senior project members from different organizations, we found that congruence between performance and mastery climates is positively and significantly related to collaboration behavior in teams. Furthermore, we highlight the moderating role of prosocial motivation in the relationship between (in)congruence in motivational climates and collaboration. Specifically, we find that under conditions of low prosocial motivation, a focus on either a mastery or a performance climate is preferable to adopting a congruence between these two climates, at least in terms of collaboration in teams
Water use, transpiration and crop coefficients for irrigated hedgerow olives grown in Southern Portugal
Olive trees are well adapted to the Mediterranean-type agro-ecosystems of southern Portugal and have traditionally been cultivated in areas with no irrigation. According to the 2009 agricultural census, the olive tree cultivation area was around 336,000 ha, of which 164,000 ha are in the southern province of Alentejo. In this southern region of semi arid Mediterranean climate where the erratic annual precipitation of around 300 to 550 mm is not enough to fulfil crop water requirements when needed, summer irrigation is a necessity to prevent crop water stress and ensure profitable yields. Hundreds of high and also very high tree-density hedgerow orchards of the Spanish cultivar Arbequina have recently been established in the region to take advantage of the European Commission decision 2000/406/CE (Official Journal L 154, 27/06/2000 P. 0033-0033) that allowed the expansion of Portuguese olive tree planting quota to 30,000 ha of new orchards. With enhanced olive production and yield depending on irrigation water supply and management, estimating hedgerow olive orchard water uptake in southern Portugal and appropriately scheduling irrigation have since been the primary concern of researchers, farmers and water resources managers. The objective of this study was to establish relationships between olive transpiration and crop transpiration coefficients of very high tree-density hedgerow orchard grown in Alentejo under well-irrigated treatment A (3.05 mm d-1) and sustained deficit irrigation treatment B (2.12 mm d-1) regimes, to understand and improve their irrigation management. On both treatments, daily transpiration at the stand scale (mm day-1) was obtained by sap flow and by dividing the tree transpiration by the area of the planting pattern. The results were compared to the daily outputs obtained with the Penman-Monteith “big leaf” equation coupled with the Orgaz et al. (2007) specific model of bulk daily canopy conductance (Gc) for unstressed olive canopies. With the Willmott index of agreement IA and the root-mean-square error RMSE above 0.8 and below 0.4 mm d-1, respectively (Willmott, 1982), the synthetic model proved sufficiently precise to be used as an appropriate simulation tool for predicting olive stand transpiration for the region. Crop and stress transpiration coefficients were proposed for both treatments
Estimation and mapping transpiration with basal and stress crop coefficients derived from remote sensing and ground-based plant water stress indicator
The use of remote sensing for obtaining evapotranspiration (ET) from natural and agricultural surfaces is already widely used. For irrigated agriculture the two basic approaches are: (1) the solution of the energy balance equation, using remotely sensed surface temperatures and reflectances to estimate variables and components of this equation, and (2) the crop coefficient and reference evapotranspiration (ETo) approach where the crop coefficient is obtained through canopy reflectance measurements. For the latter, theoretical and field studies have shown that satellite reflectance-derived vegetation indices (VIs) are closely relate to carbon and moisture fluxes and, when combined with ground data or appropriately calibrated models, they can produce valuable estimates of crop transpiration and related processes at the canopy or ecosystem scale (D ́Urso and Calera, 2006). In this study the crop coefficient approach was used. For estimation of actual transpiration of irrigated and very high tree-density hedgerow orchards grown in Alentejo the procedure correlates (a) the basal crop transpiration coefficients (Kcb = Tmax/ETo) of the unstressed full irrigated treatment to the normalized difference vegetation index (NDVI) values assessed from Landsat5 TM and Landsat7 ETM+ (r2 = 0.86) and (b) the crop stress coefficient (Ks = Ta/KcbETo), obtained from the ratio of the sustained deficit irrigation (Ta) and fully irrigated (Tmax) daily transpiration rates, to a plant stress indicator, in the case, the basal leaf water potential (r2= 0.85). Daily tree transpiration rates on both treatments were obtained from sap flow measurements. The unstressed crop status of the full irrigation treatment was warranted from the high Willmott index of agreement (IA = 0.88) obtained with transpiration values simulated with the Penman-Monteith “big leaf” model (Willmott, 1982). In this algorithm, a specific model of bulk daily canopy conductance (Gc) for unstressed olive canopies was used (Orgaz et al., 2007). From the resulting relationship equations, known field values of leaf basal water potential and satellite-derived NDVI ́s suffice to get estimates of Ks and Kcb, respectively and from them derive and map the actual olive tree transpiration (Ta = Kcb Ks ETo) rates. The study is under way, and thus further validation applications are planned prior to using the approach for mapping olive transpiration orchards of different tree density and scale areas
Comparison of soil quality indexes calculated by network and principal component analysis for carbonated soils under different uses
There is an urgent need to conserve and improve the quality of agricultural soils in the coming decades. Decision tools capable of providing reliable information about soil quality are needed, and soil quality index (SQI) is one of the most used. Principal component analysis (PCA) is the common methodology to calculate it, however in some cases fails to differentiate soil quality properly. Therefore, the aim of this work is to assess a SQI through a different methodology as network analysis (NTA) and compare it with PCA, assuming that soil uses affect soil qualities differently. From soils with different uses (rainfed, olive grove and forest) network analysis and principal component analysis have been used to select a minimum dataset (MDS) to generate SQI from 36 physical, chemical and biological soil variables. Using NTA, geometric mean of the enzyme activities (GMEAN), bulk density (BD) and phosphatase activity (phos) where selected as indicators, while PCA selected total organic carbon (TOC), free Fe oxides (FeF), crystalline Mn oxides (MnX), pH, electrical conductivity (EC) and percentage of coarse sand (CS). Four SQI were calculated from each MDS through linear and non-linear scoring equations and by additive integration and weights. The SQI generated by NTA were more useful than those generated by PCA, as in addition to having fewer indicators they were able to better differentiate the uses in the study. This greater resolution capacity of the NTA would be the consequence of a better selection of indicators using this method than using PCA
Natural selection on plant resistance to herbivores in the native and introduced range
Citation: Valverde PL, Arroyo J, Nú ñ ez-Farfá n J, Castillo G, Calahorra A, Pérez-Barrales R, Tapia-Ló pez R. 2015. Natural selection on plant resistance to herbivores in the native and introduced range. AoB PLANTS 7: plv090; doi:10.1093/aobpla/plv090 Abstract. When plants are introduced into new regions, the absence of their co-evolved natural enemies can result in lower levels of attack. As a consequence of this reduction in enemy pressure, plant performance may increase and selection for resistance to enemies may decrease. In the present study, we compared leaf damage, plant size and leaf trichome density, as well as the direction and magnitude of selection on resistance and plant size between non-native (Spain) and native (Mexico) populations of Datura stramonium. This species was introduced to Spain about five centuries ago and constitutes an ideal system to test four predictions of the enemy release hypothesis. Compared with native populations, we expected Spanish populations of D. stramonium to have (i) lower levels of foliar damage; (ii) larger plant size; (iii) lower leaf trichome density that is unrelated to foliar damage by herbivores; and (iv) weak or no selection on resistance to herbivores but strong selection on plant size. Our results showed that, on average, plants from non-native populations were significantly less damaged by herbivores, were less pubescent and were larger than those from native populations. We also detected different selection regimes on resistance and plant size between the non-native and native ranges. Positive selection on plant size was detected in both ranges (though it was higher in the non-native area), but consistent positive selection on relative resistance was detected only in the native range. Overall, we suggest that changes in selection pressure on resistance and plant size in D. stramonium in Spain are a consequence of 'release from natural enemies'
The Azorean Biodiversity Portal: an internet database for regional biodiversity outreach
Copyright © 2010 The Natural History Museum.There is a growing interest in academia to provide biodiversity data to both the scientific community and the public. We present an internet database of the terrestrial lichens, bryophytes, vascular plants, molluscs, arthropods, vertebrates and coastal invertebrates of the Azores archipelago (Portugal, North Atlantic): the Azorean Biodiversity Portal (ABP, http://www.azoresbioportal.angra.uac.pt/). This is a unique resource for fundamental research in systematics, biodiversity, education and conservation management. The ABP was based on a regional species database (ATLANTIS), comprised of grid-based spatial incidence information for c. 5000 species. Most of the data rely on a comprehensive literature survey (dating back to the 19th century) as well as unpublished records from recent field surveys in the Azores. The ABP disseminates the ATLANTIS database to the public, allowing universal, unrestricted access to much of its data. Complementarily, the ABP includes additional information of interest to the general public (e.g. literature on Macaronesian biodiversity) together with images from collections and/or live specimens for many species. In this contribution we explain the implementation of a regional biodiversity database, its architecture, achievements and outcomes, strengths and limitations; we further include a number of suggestions in order to implement similar initiatives
PROCES KSZTAŁCENIA W ZAKRESIE PROFILAKTYKI I KONTROLI ZAKAŻEŃ ZWIĄZANYCH Z OPIEKĄ ZDROWOTNĄ W EUROPEJSKICH INSTYTUCJACH SZKOLNICTWA WYŻSZEGO – BADANIE JAKOŚCIOWE
[EN] Healthcare-associated infections (HCAIs) affect
the lives of patients through prolonged stay in hospital, illness, or
even death, incurring signifi cant costs to both healthcare systems
and society. Research shows that during a stay in a hospital, approximately
20% to 30% of patients are diagnosed with at least
one infection.
Openness, fi ne interpersonal and communication skills as well as
adequate opportunities for training courses for healthcare staff
contribute to promoting HCAI/HAI prevention.
HCAI/HAI-related education should contribute to widening knowledge
and mastering practical skills. It is assumed that lecturers,
professional instructors, and coordinators create a signifi cant foundation
for professional development and social interactions by
applying interactive pedagogical models.
[POL] Zakażenia związane z opieką zdrowotną (Healthca-
re associated infections, HCAI) wpływają na życie pacjentów poprzez
przedłużony pobyt w szpitalu, chorobę, a nawet śmierć, powodując
znaczne koszty zarówno dla systemów opieki zdrowotnej, jak i spo-
łeczeństwa. Badania pokazują, że podczas pobytu w szpitalu u około
20% do 30% pacjentów diagnozuje się co najmniej jedną infekcję
Otwarte podejście, wysokie umiejętności interpersonalne i komu-
nikacyjne, a także odpowiednie możliwości szkoleń dla personelu
medycznego przyczyniają się do promowania profi laktyki HCAI/
HAI. Kształcenie w zakresie HCAI/HAI powinno przyczynić się
do poszerzenia wiedzy i opanowania praktycznych umiejętności.
Zakłada się, że wykładowcy, profesjonalni instruktorzy, koordy-
natorzy tworzą istotne podstawy rozwoju zawodowego i interakcji
społecznych poprzez stosowanie interaktywnych modeli pedago-
gicznych
Nursing Students' Perceptions on Healthcare-Associated Infection Control and Prevention Teaching and Learning Experience: Development and Validation of a Scale in Four European Countries
Healthcare-associated infections are one of the major concerns worldwide. This
study presents the development and the validation process of the InovSafeCare
scale and aimed at identifying and measuring the ecosystem variables related to
healthcare-associated infection (HCAI) prevention and control practices in European
nurse students. Qualitative and quantitative approaches were used to (1) elaborate an
item pool related to the educational environment, the healthcare setting environment, and
the attitudes, beliefs, and performance of the nursing students regarding HCAI prevention
and control and (2) analyze psychometric properties of the scale using factor analysis.
The validated InovSafeCare scale was applied to undergraduate nursing students of
five European Higher Education Institutions. The partial least square structural equation
modeling (PLS-SEM) method with SMART-PLS3 software was used. The study sample
consists of 657 nursing students, who responded a self-report inventory. From the
analyzed data were identified 14 factors. The InovSafeCare scale reveals good validity
and reliability of the dimensions in different European countries.info:eu-repo/semantics/publishedVersio
Nursing Students' Perceptions on Healthcare-Associated Infection Control and Prevention Teaching and Learning Experience: Development and Validation of a Scale in Four European Countries
[EN] Healthcare-associated infections are one of the major concerns worldwide. This study presents the development and the validation process of the InovSafeCare scale and aimed at identifying and measuring the ecosystem variables related to healthcare-associated infection (HCAI) prevention and control practices in European nurse students. Qualitative and quantitative approaches were used to (1) elaborate an item pool related to the educational environment, the healthcare setting environment, and the attitudes, beliefs, and performance of the nursing students regarding HCAI prevention and control and (2) analyze psychometric properties of the scale using factor analysis. The validated InovSafeCare scale was applied to undergraduate nursing students of five European Higher Education Institutions. The partial least square structural equation modeling (PLS-SEM) method with SMART-PLS3 software was used. The study sample consists of 657 nursing students, who responded a self-report inventory. From the analyzed data were identified 14 factors. The InovSafeCare scale reveals good validity and reliability of the dimensions in different European countries
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