Population collapse of habitat-forming species in the Mediterranean: a long-term study of gorgonian populations affected by recurrent marine heatwaves.

Understanding the resilience of temperate reefs to climate change requires exploring the recovery capacity of their habitat-forming species from recurrent marine heatwaves (MHWs). Here, we show that, in a Mediterranean highly enforced marine protected area established more than 40 years ago, habitat-forming octocoral populations that were first affected by a severe MHW in 2003 have not recovered after 15 years. Contrarily, they have followed collapse trajectories that have brought them to the brink of local ecological extinction. Since 2003, impacted populations of the red gorgonian Paramuricea clavata (Risso, 1826) and the red coral Corallium rubrum (Linnaeus, 1758) have followed different trends in terms of size structure, but a similar progressive reduction in density and biomass. Concurrently, recurrent MHWs were observed in the area during the 2003-2018 study period, which may have hindered populations recovery. The studied octocorals play a unique habitat-forming role in the coralligenous assemblages (i.e. reefs endemic to the Mediterranean Sea home to approximately 10% of its species). Therefore, our results underpin the great risk that recurrent MHWs pose for the long-term integrity and functioning of these emblematic temperate reefs.

Impact of climate change environmental conditions on the resilience of different formulations of the biocontrol agent Candida sake CPA-1 on grapes.

Biocontrol agents have become components of integrated crop protection systems for controlling economically important fungal pathogens. Candida sake CPA-1 is a biocontrol agent of fungal pathogens of fruits, both pre- and post-harvest. While the efficacy of different formulations have been examined previously, few studies have considered the resilience of different formulations under changing climatic conditions of elevated temperature, drought stress and increased atmospheric CO2 . This study examined the effect of (a) temperature × RH × elevated CO2 (400 vs 1000 ppm) on the temporal establishment and viability of two dry and one liquid C. sake CPA-1 formulations on grape berry surfaces; (b) temperature stress (25 vs 35°C); and (c) elevated CO2 levels. Results indicated that temperature, RH and CO2 concentration influenced the establishment and viability of the formulations but there was no significant difference between formulations. For the combined three-component factors, increased temperature (35°C) and lower RH (40%) reduced the viable populations on grapes. The interaction with elevated CO2 improved the establishment of viable populations of the formulations tested. Viable populations greater than Log 4 CFUs per g were recovered from the grape surfaces suggesting that these had conserved resilience for control of Botrytis rot in grapes. SIGNIFICANCE AND IMPACT OF THE STUDY: The interaction between environmental factors that are expected to occur in response to climate change (CC) will have a significant impact on food security and availability. Little information exists on how elevated temperature, drought stress and increased CO2 will have on the efficacy of biocontrol agents. The impact of these factors on the viability of different formulations of the biocontrol yeast Candida sake on the surface of grapes berries was evaluated for the first time. Such knowledge is critical for projecting the efficacy of biocontrol under climate change conditions and to identify formulations that have the necessary resilience to perform under CC conditions.

Antifungal effect of volatile organic compounds produced by Bacillus amyloliquefaciens CPA-8 against fruit pathogen decays of cherry.

The present work focuses on the antifungal effect of volatile organic compounds (VOCs) produced by Bacillus amyloliquefaciens CPA-8 against Monilinia laxa, M. fructicola and Botrytis cinera, three postharvest fruit pathogens of sweet cherry fruit. VOCs were evaluated with a double petri dish assay against mycelial and colony growth of target pathogens. For this purpose, CPA-8 was grown on different media and cultured for 24 and 48 h at 30 °C before assays. Data showed that mycelial growth inhibition was higher when CPA-8 was grown on Tryptone Soya Agar (TSA) while no differences were generally observed when CPA-8 was cultured for either, 24 and 48 h. Moreover, no effects were observed on colony growth. The main volatile compounds emitted by CPA-8 were identified by solid-phase microextraction (SPME)-gas chromatography as 1,3 pentadiene, acetoin (3-hydroxy-2-butanone) and thiophene. Pure compounds were also tested in vitro on mycelial growth inhibition and their EC50 values against the three pathogens were estimated. Thiophene was the most effective VOC, showing more than 82% suppression of mycelial growth at the highest concentration (1.35 µL/mL headspace) and EC50 values ranging from 0.06 to 6.67 µL/mL headspace. Finally, the effectiveness of thiophene and CPA-8 VOCs was evaluated against artificially inoculated cherry fruits. Among the target pathogens, M. fructicola was clearly controlled by CPA-8 with less than 25% of rotten fruits compared to the control (65% disease incidence) and for all pathogens, less than 37.5% of CPA-8 treated decayed fruits produced spores (disease sporulation). Otherwise, pure thiophene showed no effect against any pathogen on disease incidence and disease sporulation. The results indicated that VOCs produced by B. amyloliquefaciens CPA-8 could develop an additive antifungal effect against postharvest fruit pathogens on stone fruit.

Persistent natural acidification drives major distribution shifts in marine benthic ecosystems.

Ocean acidification is receiving increasing attention because of its potential to affect marine ecosystems. Rare CO2 vents offer a unique opportunity to investigate the response of benthic ecosystems to acidification. However, the benthic habitats investigated so far are mainly found at very shallow water (less than or equal to 5 m depth) and therefore are not representative of the broad range of continental shelf habitats. Here, we show that a decrease from pH 8.1 to 7.9 observed in a CO2 vent system at 40 m depth leads to a dramatic shift in highly diverse and structurally complex habitats. Forests of the kelp Laminaria rodriguezii usually found at larger depths (greater than 65 m) replace the otherwise dominant habitats (i.e. coralligenous outcrops and rhodolith beds), which are mainly characterized by calcifying organisms. Only the aragonite-calcifying algae are able to survive in acidified waters, while high-magnesium-calcite organisms are almost completely absent. Although a long-term survey of the venting area would be necessary to fully understand the effects of the variability of pH and other carbonate parameters over the structure and functioning of the investigated mesophotic habitats, our results suggest that in addition of significant changes at species level, moderate ocean acidification may entail major shifts in the distribution and dominance of key benthic ecosystems at regional scale, which could have broad ecological and socio-economic implications.

Optimization of packaging and storage conditions of a freeze-dried Pantoea agglomerans formulation for controlling postharvest diseases in fruit.

AIMS: This study aimed to evaluate different packaging strategies to extend the shelf life of a freeze-dried formulation of the biocontrol agent Pantoea agglomerans strain CPA-2. METHODS AND RESULTS: Different materials and atmosphere packaging conditions (vacuum and air) were analysed on formulated P. agglomerans cells stored at 25, 5 and -20°C. Results showed the viability of CPA-2 cells stored at 5 or -20°C was significantly higher than when stored at 25°C. The highest viabilities were observed with the plastic material designated as Bottle 1, in nonvacuum packaging in all storage temperatures: 50% after 3 months at 25°C, 100% after 8 months at 5°C and 100 and 74% after 12 and 18 months, respectively, at -20°C; the final concentration was 10(12) CFU g(-1), a good concentration for a commercial product. The efficacy to control blue and green mould on apples and oranges, respectively, of these packed and stored cells was similar to fresh CPA-2 cells. CONCLUSIONS: This work showed a suitable packaging strategy for a freeze-dried formulation of the CPA-2, providing a good shelf life and efficacy against the major postharvest diseases of apples and citrus based on a plastic bottle stored at cold or frozen storage conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: The last phase of the commercial development process for biocontrol agents is presented in this work. A bacterium-based product that ensures the efficacy, stability and easy application of the antagonist to control postharvest fungal diseases on fruit was successfully obtained.

Survival of the biological control agent Candida sake CPA-1 on grapes under the influence of abiotic factors.

AIMS: As reliability of preharvest applications of biological control agents (BCAs) to control fruit pathogens is highly dependent on the survival of the selected organism, this study aimed to describe the population dynamics of the yeast-BCA Candida sake (Saito & Ota) CPA-1 on grape berries under the effect of abiotic factors such as temperature, relative humidity, sunlight and rainfall. METHODS AND RESULTS: Candida sake (5 × 10(7) CFU ml(-1)), combined with different concentrations of the food additive Fungicover(®), was applied on grape berry clusters. Treated clusters were then exposed to abiotic factors in field or laboratory conditions, recovering populations to describe C. sake population dynamics. The addition of Fungicover significantly increased C. sake multiplication under optimal growth conditions and improved survival under fluctuating abiotic factors. After field applications, significant differences in populations on grape bunches exposed or covered by fine foliage were detected. Simulated rainfall washed off C. sake populations by 0·6-0·9 log units after 20 mm of rain volume. Allowing populations to establish for 24 h or more, prior to a rain event, persistence on grape berries significantly increased and the effect of rain intensity was not observable. CONCLUSIONS: Candida sake demonstrated high survival ability under unfavourable environmental conditions and persistence under intense rain. The study evidenced the importance of the first period just after application for C. sake survival on grape tissues and also the protective effect of the additive Fungicover. SIGNIFICANCE AND IMPACT OF THE STUDY: This research provides new information on the survival of C. sake under field conditions and its practical implications for recommending timing of spray with this antagonist. Our results could be useful for other yeast antagonists applied before harvest. This work, for the first time, defines population dynamics of a yeast BCA using simulated rainfall.

Mode of action of a fatty acid-based natural product to control Botrytis cinerea in grapes.

AIMS: To investigate the efficacy and mode of action of the fatty acid-based product Foodcoat(®) (FC) against Botrytis cinerea. METHODS AND RESULTS: In vitro, in vivo and field experiments were carried out to investigate the effect of different concentrations of FC on B. cinerea germination and infection of grape leaves and berries, using three selected isolates and comparing results with those achieved by the commercialized product Protector(HML) (PRT). Furthermore, the effect of field applications of FC on the grape berry microbiota was investigated. FC reduced B. cinerea germination and grape berry severity by up to 54 and 96%, respectively, compared with the untreated controls. CONCLUSIONS: Foodcoat demonstrated efficacy that was equal or greater than the registered product, PRT. A multiple mode of action was hypothesized for FC suppression of B. cinerea, including: inhibition of germination and germ tube alteration, protection of host green tissues and enhancement of the natural yeast populations on the berry surface. SIGNIFICANCE AND IMPACT OF THE STUDY: The efficacy of both products has been quantified and their modes of action described, suggesting them for field applications against B. cinerea, alone or in combined strategies. This is also the first report of a fatty acid-based product stimulating natural yeast populations on grape berries.

Hepatitis C virus reinfection among prisoners with sustained virological response after treatment for chronic hepatitis C.

BACKGROUND & AIMS: We estimated HCV reinfection rate and its associated risk factors in inmates with chronic hepatitis C who had achieved sustained virological response (SVR) after completing combination therapy while in prison. METHODS: Individuals who had achieved an SVR after treatment provided from January 2003 to December 2009 at four prisons in Catalonia, had been tested annually for HCV RNA and were in prison during 2010, were invited to complete a questionnaire regarding risk factors for reinfection. Incidence rate was calculated as 100 person-years of follow-up. Risk factors potentially associated with reinfection were evaluated by bivariate log-rank test and multivariate Cox regression analysis. RESULTS: One hundred and nineteen subjects who had achieved an SVR agreed to participate. 98% were male, with a median age of 33.3 ± 6.3 years and 81% had a history of injection drug use (IDU). After a mean follow-up of 1.4 years, HCV reinfection was identified in nine former IDUs, seven with HCV genotype switch, for an overall reinfection rate of 5.27 cases per 100 person-years. Reinfection incidence was significantly higher among active drug users (HR=12.47; 95% CI: 2.90-53.71), HIV co-infected (HR=9.95; 95% CI: 1.73-57.34), and those engaging in more than one risk behaviors after treatment (HR=7.47; 95% CI: 1.19-46.89). CONCLUSIONS: HCV reinfection among inmates after successful treatment is high especially in those with ongoing IDU. Preventative interventions at diagnosis and during and after HCV treatment should be strongly reinforced.

Candida sake CPA-1 and other biologically based products as potential control strategies to reduce sour rot of grapes.

UNLABELLED: Sour rot of grapes is becoming increasingly important disease in many wine-growing regions, while consistent chemical or biological control has not been reported. Authors evaluated relative incidence and severity of sour rot in untreated grapevines and the effect of different biologically based treatments on sour rot at harvest. Applications of Candida sake CPA-1 plus Fungicover® , Ulocladium oudemansii and chitosan were carried out in an organic vineyard in Lleida area, Spain, during the 2009 and 2010 growing seasons. At harvest, incidence and severity of sour rot were assessed. Significantly higher incidence and severity of sour rot were observed in untreated plots in 2009, when meteorological conditions after veraison were warmer. All treatments including C. sake CPA-1 significantly reduced (P < 0·05) severity of sour rot in both seasons, ranging from 40 to 67% compared with the untreated control. Incidence of sour rot was not significantly reduced by any treatment. This study helps to characterize development of sour rot in the dry Mediterranean climate conditions of the experiment, whereas also represents the first report of biological control of sour rot. Treatments with the tested biologically based products are a promising strategy to control sour rot. SIGNIFICANCE AND IMPACT OF THE STUDY: Studies on sour rot of grapes are scarce in literature, and this is the first work specifically evaluating sour rot in Spanish vineyards. Sour rot control in field conditions through applications of antagonistic micro-organisms is reported for first time in this study, showing elevated severity reductions (40-67% compared with control). As there are no options available for sour rot control in vineyards, results point Candida sake CPA-1 as an interesting control strategy against grape bunch rots.

Formulation development of the biocontrol agent Bacillus subtilis strain CPA-8 by spray-drying.

AIMS: To prepare commercially acceptable formulations of Bacillus subtilis CPA-8 by spray-drying with long storage life and retained efficacy to control peach and nectarine brown rot caused by Monilinia spp. METHODS AND RESULTS: CPA-8 24-h- and 72-h-old cultures were spray dried using 10% skimmed milk, 10% skimmed milk plus 10% MgSO(4) , 10% MgSO(4) and 20% MgSO(4) as carriers/protectants. All carriers/protectants gave good percentages of powder recovery (28-38%) and moisture content (7-13%). CPA-8 survival varied considerably among spray-dried 24-h- and 72-h-old cultures. Seventy-two hours culture spray dried formulations showed the highest survival (28-32%) with final concentration products of 1·6-3·3 × 10(9) CFU g(-1) , while viability of 24-h-old formulations was lower than 1%. Spray-dried 72-h-old formulations were selected to subsequent evaluation. Rehydration of cells with water provided a good recovery of CPA-8 dried cells, similar to other complex rehydration media tested. Spray-dried formulations stored at 4 ± 1 and 20 ± 1°C showed good shelf life during 6 months, and viability was maintained or slightly decreased by 0·2-0·3-log. CPA-8 formulations after 4- and 6 months storage were effective in controlling brown rot caused by Monilinia spp. on nectarines and peaches resulting in a 90-100% reduction in disease incidence. CONCLUSIONS: Stable and effective formulations of biocontrol agent B. subtilis CPA-8 could be obtained by spray-drying. SIGNIFICANCE AND IMPACT OF THE STUDY: New shelf-stable and effective formulations of a biocontrol agent have been obtained by spray-drying to control brown rot on peach.

Endospore production allows using spray-drying as a possible formulation system of the biocontrol agent Bacillus subtilis CPA-8.

The role of endospore production by Bacillus subtilis CPA-8 on survival during spray-drying was investigated by comparison with a non-spore-forming biocontrol agent Pantoea agglomerans CPA-2. Endospore formation promoted heat resistance in CPA-8 depending on growth time (72 h cultures were more resistant than 24 h ones). The survival of CPA-8 and CPA-2 after spray-drying was determined after being grown in optimised media for 24 and 72 h. Spray-dried 72 h CPA-8 had the best survival (32%), while CPA-2 viability was less than 2%. CPA-8 survival directly related with its ability to produce endospores. Spray-dried CPA-8 reduced Monilinia fructicola conidia germination similarly to fresh cells, demonstrating that spray-drying did not adversely affect biocontrol efficacy. Endospore production thus improves CPA-8 resistance to spray-drying. These results can provide a reliable basis for optimising of the spray-drying formulation process for CPA-8 and other microorganisms.

Infection capacities in the orange-pathogen relationship: compatible (Penicillium digitatum) and incompatible (Penicillium expansum) interactions.

Penicillium digitatum and Penicillium expansum are the most devastating pathogens of citrus and pome fruits, respectively. Whereas P. digitatum is a very specific pathogen that only infects Citrus fruits, P. expansum has a broader host range but has not been reported to be infectious in Citrus. To determine the responses of fruits and the infection capacities of both moulds, two varieties of oranges at different maturity stages, different inoculum concentrations and two different storage temperatures were studied. In compatible interactions, no significant differences in rot dynamics among harvests were found with a 10(7) conidia mL(-1) inoculum concentration at both temperatures tested (20 °C and 4 °C). However, at other inoculum concentrations, significant differences in rot dynamics were found, especially in immature fruits. Incompatible interactions showed that P. expansum could infect oranges at commercial maturity in both tested varieties. Decay incidence and severity were higher at 4 °C than at 20 °C. In addition to infection capacity studies, histochemical tests were performed to detect wound-healing compounds for both pathogens. A positive reaction for lignin was detected for both pathogens in immature oranges over a short period (48 h). In all cases, no reactions were found in control samples. Our results indicate that pathogen concentration, host maturity and storage temperature can play important roles in the defence mechanisms of fruit. Furthermore, to our knowledge, this is the first work that demonstrates that P. expansum can infect oranges under favourable conditions.

Enhanced shelf-life of the formulated biocontrol agent Bacillus amyloliquefaciens CPA-8 combining diverse packaging strategies and storage conditions.

Two effective biocontrol products (named as BA3 and BA4) based on Bacillus amyloliquefaciens CPA-8 have been reported as a potential alternative to chemical applications against brown rot caused by Monilinia spp. on stone fruit. To have practical use, this study aimed to describe the best packaging strategies (bags or flasks, atmosphere, and temperature of storage) to not only guarantee efficacy but also stability and ease of application of the products to be handled through the normal channels of distribution and storage. In terms of the viability neither the BA3 nor the BA4 product has been compromised after twelve months of storage. However, storage at 4 °C affected the stability and visual aspect of both CPA-8 formulations, mainly associated not only to the increase of RH but also aw. Moreover, it should be pointed out that flasks did not conserve refrigerated BA3 samples in a suitable way, since RH and aw increased noticeably making their visual properties unsightly after 10 months of cold storage. At that time, the BA4 products were better preserved at 4 °C when packaged in flasks. Finally, this study also demonstrated that the most suitable packaging conditions for long-term storability (stored at 22 °C) did not show any negative effect in the biocontrol efficacy of CPA-8 in nectarines artificially infected with M. fructicola and provide suitable product delivery and field application. In conclusion, these results contribute to the final stage of development of these two CPA-8 products, practically ready for registration, thus contributing to the environmental-friendly management of postharvest diseases in stone fruit.

Efficacy of environmental friendly disinfectants against the major postharvest pathogens of stone fruits on plastic and wood surfaces.

Disinfection of surface facilities during postharvest handling operation is an important practice to avoid secondary fruit infections at stone fruit packinghouses. The aim of this work was to evaluate the effect of six environmental friendly disinfectants against Monilinia fructicola, Penicillium expansum, Rhizopus spp., and Alternaria spp. on plastic and wood surfaces. Hydrogen peroxide, peracetic acid, sodium hypochlorite, Mico-E-pro®, Proallium FRD-N®, and DMC Clean-CNS® were used as the disinfectants. Untreated and surfaces treated with water were used as controls. Plastic and wood surfaces were sampled with Rodac plates at 2 and 24 h after treatments and the number of colonies were counted. In general, all disinfectants reduce the number of viable conidia from all studied surfaces. Hydrogen peroxide used in a concentration of 150 mg L-1 was the less effective disinfectant in all studied pathogens. The commercial product Mico-E-pro® composed of oregano, onion, and orange extract at a dose of 10 mg L-1 was the most effective disinfectant. Rhizopus spp. was the pathogen more resistant to the disinfectants followed by P. expansum, M. fructicola, and Alternaria spp. Water decreased the number of conidia adhered to the surface. In addition, the untreated control showed substantial conidia reduction after 24 h of artificial inoculation.

Is it possible to eliminate hepatitis C from the prisons of Catalonia, Spain, in 2021?

AIM: Predict the elimination of chronic hepatitis C in Catalan prisons. MATERIAL AND METHOD: We analyzed the trend of the prevalence of HCV-RNA and anti-hepatitis C treatments prescribed in Catalonia in the period 2002-2016. Using linear exponential smoothing from the historical values in the time series, we estimate the time required to eliminate hepatitis C as a public health problem in prisons (prevalence of hepatitis C virus RNA<1%). RESULTS: A total of 1264 treatments were administered by 12/31/2016. The prevalence of hepatitis C virus RNA was 31.2% in 2002, decreasing to 8.81% in 2016. We estimate that prevalence will reach 0-0.5% in 5 years (second half 2021; 95% CI: 2019-2025). DISCUSSION: Appropriate actions can eliminate hepatitis C infection in prisoners. We estimate that by 2021 hepatitis C infection will no longer be a public health problem in Catalonia prisons.

Impact of mild heat treatments on induction of thermotolerance in the biocontrol yeast Candida sake CPA-1 and viability after spray-drying.

AIMS: The objective of this study was to examine the induction of thermotolerance in the biocontrol agent Candida sake CPA-1 cells by mild heat treatments to enhanced survival of formulations using spray-drying. The possible role of heat-shock proteins (HSPs) biosynthesis in induced thermotolerance and the role of sugars and sugar alcohols were also determined. METHODS AND RESULTS: Studies were conducted on C. sake cells grown in molasses medium and exposed to mild temperatures of 30 and 33 degrees C during mid- (16 h), late-exponential (24 h), early- (30 h) and mid-stationary (36 h) growth phases. The effect on viability was determined both before and after spray-drying. Cycloheximide and chloramphenicol were used to examine the role of HSPs and HPLC was used to analyse the accumulation of sugar and sugar alcohols. The results indicate that both temperatures induced thermotolerance in cells of C. sake. Mild heat-adapted cells at 33 degrees C in the early- or mid-stationary phases had survival values after spray-drying significantly higher (P

CCAAT/enhancer binding protein-mediated role of thyroid hormone in the developmental expression of the kidney androgen-regulated protein gene in proximal convoluted tubules.

The kidney androgen-regulated protein (KAP) gene is exclusively expressed in proximal tubules of mouse kidney and in the uterus of pregnant females before they give birth. It displays an exquisite and differential regulation of expression by steroid and thyroid hormones (THs) in different proximal tubule segments. Whereas the pars recta (PR cells) responds to thyroid and sexual hormones, the pars convoluta (PCT cells) represents a truly androgen-dependent compartment because expression occurs only in the presence of androgens and functional androgen receptors. Nevertheless, different hypothyroidism models have indicated that TH might also contribute to the androgenic response in PCT cells. In the present study, we aimed to determine the molecular mechanisms that ultimately control KAP expression in these cells. Using several genetically deficient mouse models and different pharmacologic and hormonal treatments, we determined that thyroid and GH modulate CCAAT/enhancer binding protein alpha and beta levels that, in turn, control KAP expression in PCT cells in a developmentally dependent manner. We demonstrated that these factors bind to sites in the proximal KAP promoter, thereby collaborating with androgens for full KAP expression. Finally, we propose that TH and GH, acting through CCAAT/enhancer binding protein, may constitute a general regulatory mechanism of androgen-dependent genes in mouse kidney.

Re-shifting the ecological baseline for the overexploited Mediterranean red coral.

Overexploitation leads to the ecological extinction of many oceanic species. The depletion of historical abundances of large animals, such as whales and sea turtles, is well known. However, the magnitude of the historical overfishing of exploited invertebrates is unclear. The lack of rigorous baseline data limits the implementation of efficient management and conservation plans in the marine realm. The precious Mediterranean red coral Corallium rubrum has been intensively exploited since antiquity for its use in jewellery. It shows dramatic signs of overexploitation, with no untouched populations known in shallow waters. Here, we report the discovery of an exceptional red coral population from a previously unexplored shallow underwater cave in Corsica (France) harbouring the largest biomass (by more than 100-fold) reported to date in the Mediterranean. Our findings challenge current assumptions on the pristine state of this emblematic species. Our results suggest that, before intense exploitation, red coral lived in relatively high-density populations with a large proportion of centuries-old colonies, even at very shallow depths. We call for the re-evaluation of the baseline for red coral and question the sustainability of the exploitation of a species that is still common but ecologically (functionally) extinct and in a trajectory of further decline.

Regional and local environmental conditions do not shape the response to warming of a marine habitat-forming species.

The differential response of marine populations to climate change remains poorly understood. Here, we combine common garden thermotolerance experiments in aquaria and population genetics to disentangle the factors driving the population response to thermal stress in a temperate habitat-forming species: the octocoral Paramuricea clavata. Using eight populations separated from tens of meters to hundreds of kilometers, which were differentially impacted by recent mortality events, we identify 25 °C as a critical thermal threshold. After one week of exposure at this temperature, seven of the eight populations were affected by tissue necrosis and after 30 days of exposure at this temperature, the mean % of affected colonies increased gradually from 3 to 97%. We then demonstrate the weak relation between the observed differential phenotypic responses and the local temperature regimes experienced by each population. A significant correlation was observed between these responses and the extent of genetic drift impacting each population. Local adaptation may thus be hindered by genetic drift, which seems to be the main driver of the differential response. Accordingly, conservation measures should promote connectivity and control density erosion in order to limit the impact of genetic drift on marine populations facing climate change.

Efficacy of Candida sake CPA-1 formulation for controlling Penicillium expansum decay on pome fruit from different Mediterranean regions.

The effectiveness of a formulated product of the yeast Candida sake CPA-1 for controlling postharvest diseases on pome fruits was demonstrated in laboratory, semicommercial, and commercial trials carried out in the major pome fruit producing region of the European Union. First, one wettable powder and seven liquid formulations were tested in laboratory trials that involved two varieties of apples and two varieties of pears. In all cases, an efficacy similar to that of fresh cells was demonstrated in the control of artificial Penicillium expansum infection. After these trials, the formulated product chosen for semicommercial and commercial trials was LF1, a liquid formulation that is particularly suitable for commercial applications. In semicommercial trials, LF1 showed a performance similar to fresh cells in most trials, and the population dynamics of both fresh and formulated cells were quite stable throughout the storage period. This indicates the high viability of C. sake CPA-1 in this formulation and the absence of adverse effects during the formulation of the product, which may significantly affect both its ability to grow on fruit and its antagonistic activity. We evaluated the control of natural infection after applying the formulated product in a commercial drencher in different packinghouses. A significant reduction in the incidence of diseases was observed with a recommended dose of around 10(7) CFU/ml when natural infections were greater than 1%. In general, large quantities of yeast were observed on the surface of unwounded fruits of different pome fruit cultivars. Moreover, populations of this biocontrol agent increased rapidly on fruit surfaces and remained quite stable for a long time under commercial storage conditions. Commercial practices used in packinghouses were therefore successfully applied for this formulated product.