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The genetic variation and population structure of gene N (nucleocapsid) and part of gene L (replicase) from 13 eggplant mottle dwarf virus (EMDV) isolates from Spain were evaluated and compared with sequences of EMDV isolates from other countries retrieved from GenBank. Phylogenetic inference of part of gene L showed three main clades, one containing an EMDV isolate from Australia and the other two containing isolates from Iran and Europe, as well as four subclades. EMDV isolates from Spain were genetically very similar and grouped in a subclade together with one isolate from Germany and one from the UK. No new recombination events were detected in addition to one recombination previously reported, suggesting that recombination is rare for EMDV. The comparison of synonymous and non-synonymous rates showed that negative selection played an important role, and only two codons were under positive selection. Genetic differentiation (Fst test), phylogenetic and nucleotide diversity analyses suggest a unique introduction of EMDV to Spain and low gene flow with other countries. In contrast, Greece and Italy showed diverse populations with high gene flow between both. [ABSTRACT FROM AUTHOR]

We estimated the potential impact of Global Warming on the species richness of Iberian butterflies. First, we determined the grid size that maximized the balance between geographic resolution, area coverage and environmental representativeness. Contemporary richness was modelled in several alternative ways that differed in how sampling effort was controlled for, and in whether the non-climatic variables (physiography, lithology, position) were incorporated. The results were extrapolated to four WorldClim scenarios. Richness loss is to be expected for at least 70% of the area, with forecasts from the combined models being only slightly more optimistic than those from the purely climatic ones. Overall, the most intense losses are predicted for areas of highest contemporary species richness, while the potential slightly positive or nearly neutral changes would most often concentrate in cells of low to moderate present richness. The environmental determinants of richness might not be uniform across the geographical range of sampling effort, suggesting the need of additional data from the least intensively surveyed areas. Implications for insect conservation: Re-assessing richness and its environmental determinants in the area proves necessary for more detailed forecasts of the climate-driven changes in butterfly species richness. The expected future conditions imply widespread losses of regional richness, even under the less severe scenarios. Since the negative impact of warming is expected to be extensive, long term conservation plans should concentrate in the present protected areas of highest richness as these are most likely to represent the last refuges for mountain species. [ABSTRACT FROM AUTHOR]

Viruses that affect lagomorphs have decades of reported history of spillover events. One of these viruses is the causative agent of the so‐called rabbit or 'lagomorph' haemorrhagic disease (e.g. Lagovirus europaeus/GI.1 and L. europaeus/GI.2). In particular, L. europaeus/GI.2 has shown a great capacity to recombine with existing lagoviruses. In fact, it has replaced the former GI.1 genotype in the wild, and recently, an increase on spillover events has been detected among several lagomorph species including European and North American species of hares. In this study, we report for the first time the infection of a wild Iberian hare with GI.2 (RHDV2/b), potential shedding and associated histopathological alterations. We identify the recombinant GI.4P‐GI.2 as causative of the infection and discuss plausible causes regarding the origin of the spillover event and its potential consequences for the Iberian hare wild populations, which is an endemic species of the Iberian Peninsula as well as an important game and prey species for many predators, including endangered species. [ABSTRACT FROM AUTHOR]

The contribution of the HCPro factors expressed by several PVY isolates of different geographical origins (one from Scotland, one from Spain, and several from Tunisia) to differences in their virulence in Nicotiana benthamiana plants was investigated under two growing conditions: standard (st; 26 °C and current ambient levels of CO2), and climate change-associated (cc; 31 °C and elevated levels of CO2). In all cases, relative infection symptoms and viral titers were determined. The viral HCPro cistrons were also sequenced and amino-acid features of the encoded proteins were established, as well as phylogenetic distances. Additionally, the abilities of the HCPros of several isolates to suppress silencing were assessed under either growing condition. Overall, viral titers and infection symptoms decreased under cc vs. st conditions. However, within each growing condition, relative titers and symptoms were found to be isolate-specific, with titers and symptom severities not always correlating. Crucially, isolates expressing identical HCPros displayed different symptoms. In addition, all HCPro variants tested displayed comparable silencing suppression strengths. Therefore, HCPro alone could not be the main determinant of the relative differences in pathogenicity observed among the PVY isolates tested in this host, under the environments considered. [ABSTRACT FROM AUTHOR]

Simple Summary: Myxomatosis has affected the European domestic rabbit in Spain since the end of 1953; and rabbit haemorrhagic disease (RHD) since mid-1988. In this study, we describe the occurrence of myxomatosis; and RHD; on commercial rabbitries visited in Spain; between 1988 and 2018. Annual occurrence of myxomatosis decreased over 30 years. Cases of myxomatosis were detected most frequently between August and March; more cases occurring in September and fewer in June. Two important RHD epidemics occurred; the first in 1988–1989 due to classic RHD virus (RHDV), and the second from 2011 to 2013 due to new calicivirus (RHDVb/RHDV2). Monthly occurrence of RHD in 2011–2018 was higher from April to August. Despite seasonal variations of these diseases; we recommend that young breeders and adults should be protected by vaccination all year round; and on-farm hygiene measures implemented In this retrospective study, we describe the relative occurrence of clinical myxomatosis, and rabbit haemorrhagic disease (RHD), on 1714 commercial farms visited in Spain, between 1988 and 2018. We determined the annual prevalence based on 817 visits to 394 farms affected by myxomatosis. Myxomatosis was more prevalent from August to March, being lowest in June (3%) and highest in September (8.9%). With regard to RHD, we assessed 253 visits to 156 affected farms. We analyzed mean annual and monthly incidence. Two important RHD epidemics occurred; the first in 1988–1989 due to RHDV GI.1 (also known as RHDV), and the second from 2011 to 2013 due to RHDV GI.2 (RHDV2 or RHDVb). These epidemics occurred at times when effective vaccination had not been carried out. Relative monthly incidence in 2011–2018 was higher from April to August (p < 0.001). The results we obtained from 1404 necropsies on 102 farms did not clearly relate serosanguinous nasal discharge in rabbits with disease caused by GI.2 infection. We also assessed vaccination schedules used on 200 doe farms visited from the end of 2014 to 2018; 95.5% vaccinated against myxomatosis and 97.5% against RHD. Both diseases remain prevalent; however, effective vaccination has produced a steady decline in myxomatosis and RHDV GI.1 and GI.2 on-farm detection. The maintenance of high hygienic standards will be needed to continue and improve this control. However, further studies are required to investigate the causes of sustained virus presence and vaccine breaks. [ABSTRACT FROM AUTHOR]