Host adaptation and specialization in Tetranychidae mites.

Composite generalist herbivores are comprised of host-adapted populations that retain the ability to shift hosts. The degree and overlap of mechanisms used by host-adapted generalist and specialist herbivores to overcome the same host plant defenses are largely unknown. Tetranychidae mites are exceptionally suited to address the relationship between host adaptation and specialization in herbivores as this group harbors closely related species with remarkably different host ranges-an extreme generalist the two-spotted spider mite (Tetranychus urticae Koch [Tu]) and the Solanaceous specialist Tetranychus evansi (Te). Here, we used tomato-adapted two-spotted spider mite (Tu-A) and Te populations to compare mechanisms underlying their host adaptation and specialization. We show that both mites attenuate induced tomato defenses, including protease inhibitors (PIs) that target mite cathepsin L digestive proteases. While Te solely relies on transcriptional attenuation of PI induction, Tu and Tu-A have elevated constitutive activity of cathepsin L proteases, making them less susceptible to plant anti-digestive proteins. Tu-A and Te also rely on detoxification of tomato constitutive defenses. Te uses esterase and P450 activities, while Tu-A depends on the activity of all major detoxification enzymatic classes to disarm tomato defensive compounds to a lesser extent. Thus, even though both Tu-A and Te use similar mechanisms to counteract tomato defenses, Te can better cope with them. This finding is congruent with the ecological and evolutionary times required to establish mite adaptation and specialization states, respectively.

Plant, pest and predator interplay: tomato trichomes effects on Tetranychus urticae (Koch) and the predatory mite Typhlodromus (Anthoseius) recki Wainstein.

Trichomes are well-known efficient plant defense mechanisms to limit arthropod herbivory, especially in Solanaceae. The present study aims to evaluate the impact of trichome types on the development, survival and dispersal of Tetranychus urticae, and the phytoseiid predatory mite Typhlodromus (Anthoseius) recki. Six Solanum lycopersicum cultivars and two wild Solanum species, S. cheesmaniae and S. peruvianum, presenting contrasting densities and types of trichomes, were considered. Cultivars and species were characterized by counting each trichome type on leaves, petioles and stems. Mites stuck on petiole and stem and alive mites on the leaflet used for mite release and in the whole plant were counted three weeks after T. urticae plant infestation. Tetranychus urticae settlement and dispersal were differently affected by trichomes. Trichome types V and VI did not affect settlement and dispersal, whereas trichome types I and IV on the petiole had the highest impacton mites. Trichomes on leaves slightly affected mite establishment, there appears to be a repellent effect of trichome types I and IV. The low densities of both T. urticae and its predator detected for the cv. Lancaster could not be clearly associated to the trichome types here considered. The predator did not seem to be affected by plant characteristics, but rather by T. urticae numbers on the plant. The trichome traits unfavorable to T. urticae, did not affect the predator which showed high efficiency to control this pest on all the plant genotypes considered, but at a favorable predator:prey ratio (1:1). Altogether, these results are encouraging for the use of T. (A.) recki as a biological control agent of T. urticae regardless of the trichome structure of the tomato cultivars, but other conditions should be tested to conclude on practical implementations.

Natural versus conventional production of Spanish white wines: an exploratory study.

BACKGROUND: Natural wine (NW) lacks an official or agreed definition, but it can be generally described as a wine produced with organic or biodynamic grapes with minimal intervention in the cellar, and with minimal or no use of oenological additives. The present study aimed to test the hypotheses that self-defined NWs differ from conventional wines (CW) in their chemical composition and main sensory characteristics. The levels of conventional oenological parameters, turbidity, biogenic amines, ochratoxin A, ethyl carbamate, sulphites, chlorides, some metals, major, trace and Strecker aldehyde volatile compounds were determined in 28 wines, including natural and conventional Spanish commercial white wines. Wines were also sensory described following a labelled free sorting task. RESULTS: NWs presented higher pH, volatile acidity (VA) and turbidity values, and a more intense yellow colour, whereas they have a lower malic acid content compared to theor conventional counterparts. NWs presented lower levels of total sulphur dioxide but significantly higher levels of biogenic amine putrescine, although both compounds are within the legal limits in all cases. None of the dimensions of the similarity space discriminated NWs from CWs. However, 70% of the NWs were grouped on the basis of various aromatic defects related to their higher content in 4-ethylphenols and VA. The remaining 30% were not differentiated from their conventional counterparts. CONCLUSION: It could be confirmed that NW can be globally differentiated from CW with respect to to their chemical and their sensory profiles, whereas the content in toxicants was not significantly different, with the exception of total sulphur dioxide and putrescine levels. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

How has COVID-19, lockdown and social distancing changed alcohol drinking patterns? A cross-cultural perspective between britons and spaniards.

During the early months of 2020, the world experienced a novel, violent, and relentless pandemic era. By the end of the year more than seventy-seven million cases of COVID-19 had been reported around the globe. Due to it being a highly contagious disease, the recommended measures adopted by most nations to prevent infection include social distancing and quarantine. How did these measures affect people's relationship with alcohol consumption in cultures where alcohol plays an important social role? A questionnaire-based study, designed to follow the drinking behaviour of people before and during lockdown was applied to two different cultural groups impacted by the pandemic during the strict phase of lockdown. These are the British and Spanish populations (179 participants from each country were interviewed). Considering the frequency of consumption of the alcoholic beverages evaluated (wine, beer, cider, whisky and spirits), the results showed that a significant lockdown*country interaction was observed. Overall, Spanish participants consumed alcoholic beverages less frequently during lockdown than before, while British participants reported no change in their consumption habits. Spaniards' decrease in alcohol consumption is related to the absence of a social contexts while Britons seems to have adapted their consumption to the modified context. Results suggest that, alcohol consumption is a central core of the British culture, while for the Spanish, socialization is more a cultural characteristic than the alcohol itself.

To fear the unknown: Covid-19 confinement, fear, and food choice.

The coronavirus outbreak in December 2019 completely changed the dynamic of consumption in different sectors of industry. The food and beverage industries have been profoundly affected, from production, to modifications in consumers' choices. Among the different reasons behind those modifications is confinement, which forces consumers to stay at home for an extended period and just go out to perform essential tasks, such as going to the supermarket. We hypothesized that this new dynamic of consumption could create a situation of fear that changes food choice. To test this hypothesis, two studies were conducted in three countries with a different degree of confinement: Mexico (flexible), Spain (strict), and Peru (hard). Study one consisted of a free association task with 60 participants in each country with the inductor word "coronavirus and food". The different associations served as the basis to build a structured questionnaire, which was used in the second study focused on fear and food choice. The second study was applied to 450 participants in the same three countries. Results showed that fear can be separated into nine dimensions: social, emotional, food supply, government, basic needs, food-delivery, overeating, immunity, and family conflicts. The participants could also be clustered into four different groups that differ in their country of origin and sex, but also in their food choice. Overall, the results showed that fear influenced consumer's food choices during a confinement period.

Wine quality and berry size: a case study with Tempranillo Tinto progenies.

BACKGROUND: Small berry size is normally associated with quality wine production. However, the contribution of grapevine variety and environment to sensory quality has not been well established. In this study, genotypes from two intra-specific hybrid populations were categorized by size according to berry diameter and weight: small (< 13.5 mm, <1.5 g), and large (>16 mm, >2 g). Chemical and sensory attributes of wines produced in two consecutive vintages (2017 and 2018) from each size category were characterized. Perceived intrinsic wine quality was judged by 20 wine professionals. RESULTS: Wines obtained from small berry genotypes consistently displayed higher proportions of phenolic compounds and deeper color and were judged higher in quality regardless of genetic background and vintage. Perceived quality was positively correlated with anthocyanin and phenolic content. Wines presented high sensory variability in both vintages. Small berry size genotypes produced sweeter, fruitier wines with greater astringency; whereas wines from larger berries were perceived as more alcoholic and with lower positive aroma intensities. Berry size influenced color and phenolic compounds more than genotype or environment. CONCLUSION: Small berry-size genotypes were related to high quality judgements in both years, thus providing a predictor of wine categories, which could be used to meet different market demands. © 2020 Society of Chemical Industry.

Aroma profiling of an aerated fermentation of natural grape must with selected yeast strains at pilot scale.

The use of non-Saccharomyces strains in aerated conditions has proven effective for alcohol content reduction in wine during lab-scale fermentation. The process has been scaled up to 20 L batches, in order to produce lower alcohol wines amenable to sensory analysis. Sequential instead of simultaneous inoculation was chosen to prevent oxygen exposure of Saccharomyces cerevisiae during fermentation, since previous results indicated that this would result in increased acetic acid production. In addition, an adaptation step was included to facilitate non-Saccharomyces implantation in natural must. Wines elaborated with Torulaspora delbrueckii or Metschnikowia pulcherrima in aerated conditions contained less alcohol than control wine (S. cerevisiae, non-aerated). Sensory and aroma analysis revealed that the quality of mixed fermentations was affected by the high levels of some yeast amino acid related byproducts, which suggests that further progress requires a careful selection of non-Saccharomyces strains and the use of specific N-nutrients.

The genome of Tetranychus urticae reveals herbivorous pest adaptations.

The spider mite Tetranychus urticae is a cosmopolitan agricultural pest with an extensive host plant range and an extreme record of pesticide resistance. Here we present the completely sequenced and annotated spider mite genome, representing the first complete chelicerate genome. At 90 megabases T. urticae has the smallest sequenced arthropod genome. Compared with other arthropods, the spider mite genome shows unique changes in the hormonal environment and organization of the Hox complex, and also reveals evolutionary innovation of silk production. We find strong signatures of polyphagy and detoxification in gene families associated with feeding on different hosts and in new gene families acquired by lateral gene transfer. Deep transcriptome analysis of mites feeding on different plants shows how this pest responds to a changing host environment. The T. urticae genome thus offers new insights into arthropod evolution and plant-herbivore interactions, and provides unique opportunities for developing novel plant protection strategies.

Rapid sensory-directed methodology for the selection of high-quality aroma wines.

BACKGROUND: The present work contributes by developing a rapid sensory-directed methodology for the screening and selection of high-quality wines with different sensory profiles. Verdejo and Tempranillo musts were fermented with 50 different yeasts each under controlled laboratory conditions. Resulting samples were firstly categorised according to five levels of quality by a panel of wine professionals. Higher quality samples were described by flash profiling by a semi-trained panel and most distinctive samples were screened by gas chromatography-olfactometry (GC-O). RESULTS: Seven Verdejo and five Tempranillo samples were classified in the highest quality category, presenting different aroma profiles such as citrus, fruit in syrup, boxtree/vegetal, tropical or wet grain aromas for Verdejo and red fruit or fruit in syrup for Tempranillo. ß-Damascenone, 3-mercaptohexyl acetate and ethyl butyrate appeared as distinctive quality compounds linked to dried, tropical and red fruit aromas, respectively. CONCLUSIONS: The categorisation task followed by flash profiling and GC-O analysis was shown to be a rapid and effective sensory-directed methodology for the screening of distinctive and quality wine aroma profiles in a case study of yeast selection. The wine industry could benefit from the use of this methodology as a complementary tool for optimising different technical processes. © 2016 Society of Chemical Industry.

Tomato Whole Genome Transcriptional Response to Tetranychus urticae Identifies Divergence of Spider Mite-Induced Responses Between Tomato and Arabidopsis.

The two-spotted spider mite Tetranychus urticae is one of the most significant mite pests in agriculture, feeding on more than 1,100 plant hosts, including model plants Arabidopsis thaliana and tomato, Solanum lycopersicum. Here, we describe timecourse tomato transcriptional responses to spider mite feeding and compare them with Arabidopsis in order to determine conserved and divergent defense responses to this pest. To refine the involvement of jasmonic acid (JA) in mite-induced responses and to improve tomato Gene Ontology annotations, we analyzed transcriptional changes in the tomato JA-signaling mutant defenseless1 (def-1) upon JA treatment and spider mite herbivory. Overlay of differentially expressed genes (DEG) identified in def-1 onto those from the timecourse experiment established that JA controls expression of the majority of genes differentially regulated by herbivory. Comparison of defense responses between tomato and Arabidopsis highlighted 96 orthologous genes (of 2,133 DEG) that were recruited for defense against spider mites in both species. These genes, involved in biosynthesis of JA, phenylpropanoids, flavonoids, and terpenoids, represent the conserved core of induced defenses. The remaining tomato DEG support the establishment of tomato-specific defenses, indicating profound divergence of spider mite-induced responses between tomato and Arabidopsis.

New species and new records of Tetranychidae (Acarina, Prostigmata) from Thailand.

Sampling efforts conducted in several provinces from Thailand disclosed three new species of tetranychid mites. Two of them belong to the genus Tetranychus, namely Tetranychus occultaspina sp. nov. and Tetranychus truncatissimus sp. nov. and the third species belongs to the genus Schizotetranychus, Schizotetranychus krungthepensis sp. nov. They were collected on Ipomoea aquatica, Bambusa multiplex and Saccharum officinarum, respectively. New records and new hosts are also mentioned. 

Attitudes towards natural wines among Spanish winemakers: Relationship with environmental awareness.

There is an important movement in the wine industry towards the production of alternative and more sustainable wines. Natural wine (NW) is a controversial category of alternative wines, which needs to be further explored. Given the role of technical experts as opinion leaders, the present work aims to explore the attitudes of Spanish winemakers towards NW and their relationship with their overall environmental awareness. Therefore, 307 Spanish winemakers completed a questionnaire to evaluate: (1) their attitudes towards NW by scoring their agreement with 31 statements, (2) their ecological awareness by evaluating 11 items, (3) their frequency of consumption and interest towards NW, and (4) their sociodemographic profile and general information about wine production. PCA with varimax rotation calculated on 28 of the 31 statements related to their attitudes showed six independent dimensions. Further hierarchical cluster analysis calculated with the six dimensions showed five clusters of wine experts with different attitudes towards NW. Results show that there is a major negative attitude towards the flavour of NW, their ageing capacity and their quality-price ratio, but a positive one in terms of economic impact for the wine industry. Aspects related to the role of NW in tradition, social identity, ecology, health, artisanal production and economic feasibility mark differential attitudes. Interestingly, the dimension related to winemakers attitude towards tradition, social identity, and ecology of NW was positively correlated with their overall ecological awareness and thus their life style. This paper sheds light in the understanding of the behaviour of Spanish winemakers regarding ecological transition and provides tools for policymaking regarding NW certification.

Integrating ecology and genetics to address Acari invasions.

Because of their small size and tolerance to many of the control procedures used for a wide variety of commodities, Acari species have become one of the fastest, unwanted pest travelers since the beginning of this century. This special issue includes eleven studies on adventive and invasive Acari species affecting major crops and livestock around the world. The nucleus for this special issue is formed by the presentations in the symposium on invasive mites and ticks organized at the International Congress of Acarology in Recife, Brazil (ICA-13), in the summer of 2010. This special issue illustrates the increased concerns about domestic and international invasive mites and ticks worldwide.

Review of the invasion of Tetranychus evansi: biology, colonization pathways, potential expansion and prospects for biological control.

In the last two decades the subtropical red tomato spider mite, Tetranychus evansi, has expanded its geographical distribution and emerged as a major invasive agricultural pest. The mite is considered to be native to South America. Since its first report from north-eastern Brazil in 1952, it has been reported from different continents. This paper reviews literature on several aspects of the biology of T. evansi related to its status as an invasive species. It addresses taxonomical issues, occurrences, life history traits, host-plant interactions, genetic diversity of geographical isolates and worldwide colonisation pathways. It also presents updated data which allowed the assessment of the actual worldwide distribution of this species, from its discovery to the latest reports. As T. evansi is considered an emerging agricultural pest, we also present data based on modelling of the potential of T. evansi to colonize new geographical areas. In addition, this review presents past and current research on natural enemies of T. evansi potentially useful for its biological control. While summarizing the knowledge on T. evansi, the review emphasizes research possibilities that are worth pursuing, mainly concerning the ability of T. evansi to establish new populations and to detect new promising natural enemies.

Microsatellites reveal a strong subdivision of genetic structure in Chinese populations of the mite Tetranychus urticae Koch (Acari: Tetranychidae).

BACKGROUND: Two colour forms of the two-spotted spider mite (Tetranychus urticae Koch) coexist in China: a red (carmine) form, which is considered to be native and a green form which is considered to be invasive. The population genetic diversity and population genetic structure of this organism were unclear in China, and there is a controversy over whether they constitute distinct species. To address these issues, we genotyped a total of 1,055 individuals from 18 red populations and 7 green populations in China using eight microsatellite loci. RESULTS: We identified 109 alleles. We found a highly significant genetic differentiation among the 25 populations (global FST = 0.506, global FST {ENA} = 0.473) and a low genetic diversity in each population. In addition, genetic diversity of the red form mites was found to be higher than the green form. Pearson correlations between statistics of variation (AR and HE) and geographic coordinates (latitude and longitude) showed that the genetic diversity of the red form was correlated with latitude. Using Bayesian clustering, we divided the Chinese mite populations into five clades which were well congruent with their geographic distributions. CONCLUSIONS: Spider mites possess low levels of genetic diversity, limit gene flow between populations and significant and IBD (isolation by distance) effect. These factors in turn contribute to the strong subdivision of genetic structure. In addition, population genetic structure results don't support the separation of the two forms of spider mite into two species. The morphological differences between the two forms of mites may be a result of epigenetic effects.

Insights on the chemical basis of the astringency of Spanish red wines.

The main goal of the present study is to provide an insight on the role played by non-volatile molecules on the different in-mouth attributes, particularly astringency. For achieving such goal, the main in-mouth sensory attributes of 34 oaked Spanish red wines were measured by a trained panel. The wine content in 30 sensory-active molecules was analysed by different HPLC based methodologies together with classical enological parameters and two proanthocyanidin indexes. Fourteen compounds (aconitic acids, polymeric proanthocyanidins, caftaric, caffeic and coutaric acids and seven quercetins) were found to be at concentrations above reported taste thresholds and to have a reasonably high range of occurrence. Two highly statistically significant models for astringency were built with those compounds. Even if the models could not be fully validated by sensory addition experiments, the research has demonstrated that wine astringency is driven by polymeric proanthocyanidins and by certain phenolic acids, the rate trans/cis-aconitic acid and flavonol profiles. The research has highlighted the existence of extremely complex interactions between non-volatile compounds on the in-mouth sensory perception. Particularly remarkable is the lack of additivity and potential antagonism found between the pairs cis/trans-aconitic acids, between aconitic and caffeic acids and between quercetin-3-O-galactoside and quercetin-3-O-glucoside. Also remarkable was the sweetness×astringent interaction and the matrix-dependence of the sensory responses elicited by flavonols. These results suggest the need for new paradigms and experimental procedures for fully decoding the real sensory relevance of individual non-volatile compounds in the overall wine flavour.

Differences between sympatric populations of Eotetranychus carpini collected from Vitis vinifera and Carpinus betulus: insights from host-switch experiments and molecular data.

Eotetranychus carpini (Oudemans) is an important pest of grapevine (Vitis vinifera L.) in southern Europe. This mite is also found on a number of different plants, including Carpinus betulus L., which commonly occurs in stands and hedgerows bordering vineyards, where it may serve as a potential mite reservoir. The economic importance of this pest has motivated a number of studies aimed at investigating whether the mites found on V. vinifera and C. betulus are conspecific. The results obtained to date have been inconclusive. In this study, we used biological and molecular approaches to investigate this issue. First, we conducted host-switch experiments to test the ability of E. carpini to develop on an alternative host plant, using mite populations originally collected on either C. betulus or V. vinifera plants from the same area. Second, we investigated DNA-based differentiation using nucleotide sequences of the ITS1-5.8S-ITS2 region of the ribosomal DNA of individual E. carpini from the populations examined in our host-plant experiments. We also analyzed sequences of individuals collected in other regions (Italy and Slovenia) to estimate species variation. The results from our host-switch experiments suggest the differentiation of mites collected on the two hosts. Mites collected from C. betulus did not survive and reproduce on V. vinifera and vice versa. Our molecular work revealed significant genetic differentiation between the mites collected from the two hosts, but no evidence of genetic variation among specimens collected from the same host species. Our results indicate the existence of host races of E. carpini.

Modeling grape taste and mouthfeel from chemical composition.

This research aims at predicting sensory properties generated by the phenolic fraction (PF) of grapes from chemical composition. Thirty-one grape extracts of different grape lots were obtained by maceration of grapes in hydroalcoholic solution; afterward they were submitted to solid phase extraction. The recovered PFs were reconstituted in a wine model. Subsequently the wine models, containing the PFs, were sensory (taste, mouthfeel) and chemically characterized. Significant sensory differences among the 31 PFs were identified. Sensory variables were predicted from chemical parameters by PLS-regression. Tannin activity and concentration along with mean degree of polymerization were found to be good predictors of dryness, while the concentration of large polymeric pigments seems to be involved in the "sticky" percept and flavonols in the "bitter" taste. Four fully validated PLS-models predicting sensory properties from chemical variables were obtained. Two out of the three sensory dimensions could be satisfactorily modeled. These results increase knowledge about grape properties and proposes the measurement of chemical variables to infer grape quality.