39 research outputs found
Impacts of climate change on plant diseases – opinions and trends
There has been a remarkable scientific output on the topic of how climate change is likely to affect plant diseases in the coming decades. This review addresses the need for review of this burgeoning literature by summarizing opinions of previous reviews and trends in recent studies on the impacts of climate change on plant health. Sudden Oak Death is used as an introductory case study: Californian forests could become even more susceptible to this emerging plant disease, if spring precipitations will be accompanied by warmer temperatures, although climate shifts may also affect the current synchronicity between host cambium activity and pathogen colonization rate. A summary of observed and predicted climate changes, as well as of direct effects of climate change on pathosystems, is provided. Prediction and management of climate change effects on plant health are complicated by indirect effects and the interactions with global change drivers. Uncertainty in models of plant disease development under climate change calls for a diversity of management strategies, from more participatory approaches to interdisciplinary science. Involvement of stakeholders and scientists from outside plant pathology shows the importance of trade-offs, for example in the land-sharing vs. sparing debate. Further research is needed on climate change and plant health in mountain, boreal, Mediterranean and tropical regions, with multiple climate change factors and scenarios (including our responses to it, e.g. the assisted migration of plants), in relation to endophytes, viruses and mycorrhiza, using long-term and large-scale datasets and considering various plant disease control methods
Host Responses in Life-History Traits and Tolerance to Virus Infection in Arabidopsis thaliana
Knowing how hosts respond to parasite infection is paramount in understanding the effects of parasites on host populations and hence host–parasite co-evolution. Modification of life-history traits in response to parasitism has received less attention than other defence strategies. Life-history theory predicts that parasitised hosts will increase reproductive effort and accelerate reproduction. However, empirical analyses of these predictions are few and mostly limited to animal-parasite systems. We have analysed life-history trait responses in 18 accessions of Arabidopsis thaliana infected at two different developmental stages with three strains of Cucumber mosaic virus (CMV). Accessions were divided into two groups according to allometric relationships; these groups differed also in their tolerance to CMV infection. Life-history trait modification upon virus infection depended on the host genotype and the stage at infection. While all accessions delayed flowering, only the more tolerant allometric group modified resource allocation to increase the production of reproductive structures and progeny, and reduced the length of reproductive period. Our results are in agreement with modifications of life-history traits reported for parasitised animals and with predictions from life-history theory. Thus, we provide empirical support for the general validity of theoretical predictions. In addition, this experimental approach allowed us to quantitatively estimate the genetic determinism of life-history trait plasticity and to evaluate the role of life-history trait modification in defence against parasites, two largely unexplored issues
Vampires in the village Žrnovo on the island of Korčula: following an archival document from the 18th century
Središnja tema rada usmjerena je na raščlambu spisa pohranjenog u Državnom arhivu u Mlecima (fond: Capi del Consiglio de’ Dieci: Lettere di Rettori e di altre cariche) koji se odnosi na događaj iz 1748. godine u korčulanskom selu Žrnovo, kada su mještani – vjerujući da su se pojavili vampiri – oskvrnuli nekoliko mjesnih grobova. U radu se podrobno iznose osnovni podaci iz spisa te rečeni događaj analizira u širem društvenom kontekstu i prate se lokalna vjerovanja.The main interest of this essay is the analysis of the document from the State Archive in Venice (file: Capi del Consiglio de’ Dieci: Lettere di Rettori e di altre cariche) which is connected with the episode from 1748 when the inhabitants of the village Žrnove on the island of Korčula in Croatia opened tombs on the local cemetery in the fear of the vampires treating.
This essay try to show some social circumstances connected with this event as well as a local vernacular tradition concerning superstitions
Adapting forest health assessments to changing perspectives on threats – a case example from Sweden
A revised Swedish forest health assessment
system is presented. The assessment system
is composed of several interacting components
which target information needs for strategic
and operational decision making and accommodate
a continuously expanding knowledge base.
The main motivation for separating information
for strategic and operational decision making is
that major damage outbreaks are often scattered
throughout the landscape. Generally, large-scale
inventories (such as national forest inventories)
cannot provide adequate information for mitigation
measures. In addition to broad monitoring
programs that provide time-series information on
known damaging agents and their effects, there
is also a need for local and regional inventories
adapted to specific damage events. While information
for decision making is the major focus of
the health assessment system, the system also contributes
to expanding the knowledge base of forest
conditions. For example, the integrated monitoring
programs provide a better understanding of
ecological processes linked to forest health. The
new health assessment system should be able to
respond to the need for quick and reliable information
and thus will be an important part of the
future monitoring of Swedish forests
Comparative outcome one year after formal cardiac rehabilitation: the effects of a randomized intervention to improve exercise adherence
BACKGROUND: Methods to ensure sustained benefits of cardiac rehabilitation need to be explored. The aim was to assess the effect of a home-based intervention (INT) on exercise adherence and risk factors after cardiac rehabilitation. DESIGN: Prospective randomized study. METHODS: We evaluated patients who were followed for 1 year after either inpatient (ICR) or outpatient cardiac rehabilitation (OCR) by assessment of exercise capacity, physical activity, risk factors and quality of life, both at the completion of rehabilitation, and after 1 year. Patients were randomized to either be instructed how to use a diary of physical activities complemented by quarterly group meetings (INT) or to receive standard treatment (usual care). RESULTS: Two hundred and sixty-one patients gave consent to be reevaluated after 1 year. Of these patients 33 were lost to follow-up (two deaths); thus 228 patients had complete 1-year follow-up data (195 male and 33 female, 91% with coronary artery disease). At 1-year follow-up significantly more patients of the INT group than of the control group adhered to regular physical activity (73 vs. 40%, P>0.0001). Moreover, INT patients showed a better evolution of body mass index and lipid values. In a stepwise multiple regression analysis the following variables showed a significant impact on regular physical activity at follow-up: study INT [odds ratio (OR): 4.19, P>0.0001], previous cardiac surgery (OR: 2.50, P=0.008), BMI at baseline (OR: 0.89, P=0.018) and quality of life at baseline (OR: 1.58, P=0.041). CONCLUSION: Sustained benefits of cardiac rehabilitation can be documented 1 year after both inpatient and outpatient programmes. Self-monitoring of physical activity greatly increased long-term adherence to regular exercise, which in turn was associated with greater improvements of risk factors and quality of life