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Drought is a major threat to crop production worldwide and is accentuated by global warming. Plant responses to this abiotic stress involve physiological changes overlapping, at least partially, the defense pathways elicited both by viruses and their herbivore vectors. Recently, a number of theoretical and empirical studies anticipated the influence of climate changes on vector-borne viruses of plants and animals, mainly addressing the effects on the virus itself or on the vector population dynamics, and inferring possible consequences on virus transmission. Here, we directly assess the effect of a severe water deficit on the efficiency of aphid-transmission of the Cauliflower mosaic virus (CaMV) or the Turnip mosaic virus (TuMV). For both viruses, our results demonstrate that the rate of vector-transmission is significantly increased from water-deprived source plants: CaMV transmission reproducibly increased by 34% and that of TuMV by 100%. In both cases, the enhanced transmission rate could not be explained by a higher virus accumulation, suggesting a more complex drought-induced process that remains to be elucidated. The evidence that infected plants subjected to drought are much better virus sources for insect vectors may have extensive consequences for viral epidemiology, and should be investigated in a wide range of plant-virus-vector systems.

Atmospheric carbon dioxide (CO2) concentration has increased significantly and is projected to double by 2100. To increase current food production levels, understanding how pests and diseases respond to future climate driven by increasing CO2 is imperative. We investigated the effects of elevated CO2 (eCO2) on the interactions among wheat (cv. Yitpi), Barley yellow dwarf virus and an important pest and virus vector, the bird cherry-oat aphid (Rhopalosiphum padi), by examining aphid life history, feeding behavior and plant physiology and biochemistry. Our results showed for the first time that virus infection can mediate effects of eCO2 on plants and pathogen vectors. Changes in plant N concentration influenced aphid life history and behavior, and N concentration was affected by virus infection under eCO2. We observed a reduction in aphid population size and increased feeding damage on noninfected plants under eCO2 but no changes to population and feeding on virus-infected plants irrespective of CO2 treatment. We expect potentially lower future aphid populations on noninfected plants but no change or increased aphid populations on virus-infected plants therefore subsequent virus spread. Our findings underscore the complexity of interactions between plants, insects and viruses under future climate with implications for plant disease epidemiology and crop production.

Unlabelled: Alcoholism is a major cause of death. To date, there have been reported few studies examining the factors associated with mortality in alcoholics who are hospitalized for medical reasons. The aim of this study was to analyze the survival rate of those alcoholic subjects and to identify outcome variables., Patients and Method: Among all alcoholic patients admitted from January 1986 to December 1988 in the Department of Internal Medicine 1 of the Reina Sofia University Hospital in Córdoba (Spain), 162 met the inclusion criteria. Information was compiled from protocols, medical records,death certificates and interviews to patients and family members.A prospective cohort design was also used. Average age was 50.7 (10.7) years; 91.4% were males, 69.9% smokers,65.7% were married, 19.8% had ascites, and the average follow-up was 8.7 years. 59 patients survived, 56 died, and 47 did not complete the study period. In the covariate analysis, age, marital status,alcoholism duration, bilirubin levels, ascites and albumin concentrations had statistical signification. Four variables were included in the regression model: age (OR, 1.07; 1.03-1.12); ascites (OR,2.09; 1.05-4.15); bilirubin (OR, 1.42; 1.20-1.67) and marital status (OR, 2.39; 1.17-4.85)., Conclusions: In our study, age, an increase in bilirubin level, presence of ascites, and marital status (single, widowed or separated) were associated with a significantly lower survival rate in chronic alcoholics.