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App-ExploraCítricos v2.0 is an application for measuring epidemiological variables with a spatio-temporal, multi-crop, multispecies-variety, multivariate, multi-pest, multiuser, and multicriteria approach for risk analysis in the citrus production chain. The objective of this work was to develop, and field validate an application for mobile devices with Android® 6.0 or higher, which would allow n-assessments in situ associated with a regional epidemiological process through a flexible design customized to a sanitary objective. The process begins by entering access codes for user authentication. Before an assessment, the user must configure the n-pests and/or n-diseases of interest associated with the citrus crop(s)/species(s), including the common and scientific name, and type of organism (fungus, virus, bacterium, etc.). The settings are stored locally for the further assessment process. Subsequently, n-scales with n-independent, qualitative or quantitative classes are configured to assess occurrence, severity, or infestation per organism. In addition, the presence/absence or vector infestation level can be assessed. Once the assessment criteria have been customized for a regional scenario, sampling begins in n-plantations with individual characterization using 26-epidemiological-productive variables, e.g., agronomic condition, age, crop, cultivar, irrigation type, nutrition, management, etc. The assessment is performed in n-plants per plantation. Per plant, the n-pests and/or n-diseases previously configured are assessed with the respective scales. The user may take up to three georeferenced photographs of pest infestation or symptoms for eventual further sampling for etiological purposes. The assessment(s) is virtually submitted to a web database, exported, or shared via email, Bluetooth, social media, or other device tools. The App was successfully validated on citrus crops of San Luis Potosi, Veracruz, and Chiapas states for CTV, CLas, CiLV, and their respective vectors with a total of 58 plantations and 37700 metadata generated. The App-ExploraCítricos v2.0 is a phytosanitary innovation that may contribute to the integration of large volumes of relevant, standardized, and quality data for risk analysis and management in citrus farming. [ABSTRACT FROM AUTHOR]

In Mexico, Theobroma cacao is affected by the black pod rot (BPR) caused by Phytophthora capsici. Currently, an epidemiological study of this disease is lacking. The objective was to determine the influence of climate, fruit set and the incidence of cacao frosty pod rot (Moniliophthora roreri) on the epidemic intensity of BPR in five locations in southeastern Mexico. The temporal structure of BPR epidemics was analyzed and the correlation of absolute change of BPR incidence with temperature, relative humidity (RH), precipitation, and fruiting flows was studied. The possible competition between P. capcisi and M. roreri was also analyzed correlatively. The epidemics had a duration of 15 to 25 weeks restricted to September - February with 6 to 24% final incidence (Yf ). The curves were best fitted to the Gompertz model (r = 0.059 - 0.123, R2 0.97 - 0.99) with an exponential phase in October corresponding with the highest rainfall. BPR was positively associated with RH greater than 90%, precipitation, temperature periods lower than 19.9, and 20 - 26.9 °C, and with fruiting intensity. P. capcisi had less parasitic fitness than M. roreri, which induced earlier epidemics, with greater duration and intensity. The characterization of BPR as a polycyclic epidemic justifies management strategies aimed at reducing the secondary inoculum. [ABSTRACT FROM AUTHOR]

The research objective was to identify the Fusarium specie(s) associated with commercial offsets of Agave tequilana and to develop a methodology to quantify the inoculum load in offsets from Jalisco mother plantations with differential epidemic inductivity to wilt and dry bud rot syndrome (SMAP). The purpose was to provide criteria for the certification of mother plantations. The samples were collect between March and May in 2018 and 2019, from 21 commercial plantations of 14 municipalities of Los Altos, South, and Valley of Jalisco. The number of diseased plants (PE) and SMAP severity (S) were estimated in 63 and 200 plants/plantation using App-SIVEA for 2018 and 2019 respectively. The CIFUSAG method was developed and applied in 7055 offsets and 46656 fungal colonies obtained from 2364 basal 'piña' wash isolates, internal tissue sections, and offset total maceration. Colony Forming Units (CFU) of Fusarium spp. (Fsp) and total fungi (HT), purification, monosporic, morphological and cultural characterization was made with Komada, water-agar, Sabouraud, SNA, and Sabouraud media, respectively, selecting 557 contrasting isolates. The highest epidemic inductivity in Los Altos was associated to moderate Fusarium Index [(FI) = (ΣFsp) / (ΣHT)] (0.30 and 0.40) and Fsp (20 and 72 CFU) compared to South, which had higher values (0.69, 0.50; 23, 84 CFU, respectively) (Tukey p=0.05). The offset base-size had no influence on FI and Fsp (p=0.183). FI and Fsp of basal 'piña' washing were not correlated with S in mother plants (r2 = 0.036 and 0.13), while PE only was correlated with Fsp (r2 = 0.94). The inoculum load obtained by washing was higher than internal tissue with a total of 17,828 CFU (93%) and FI=0.42. Molecular analysis with the EF-1a gene showed an association of 23 isolates with four phylogenetic complexes: Fusarium oxysporum, F. fujikuroi, F. solani and F. incarnatum-equiseti with identity greater than 98%. Offsets of Agave tequilana constitutes a dispersal factor of at least four species of Fusarium spp. in the range of 3.3±3 y 6.83±4.2 CFU/offset. [ABSTRACT FROM AUTHOR]

Wilt and dry bud rot of the agave (Agave tequilana var. azul) are diseases of high economic impact for this crop. The implication of Fusarium spp. in both diseases at a regional context was determined in this research. Root and soil samples were collected from 40 commercial plantations located in 13 counties at Los Altos, Jalisco an important cultivation region of agave azul in Mexico; Inoculum charge, as a Fusarium Index was obtained base on colony units (Fusarium vs total fungi) and its relationship with pH and organic matter were estimated from each sampling plantation. A total of 109 isolates were morphologically characterized as Fusarium spp. of which 25 were selected for molecular identification with ITS and EF-1a. The selection considered symptomatology, macro and microscopic characters and prevalence of colony types observed in vitro in Komada, Sabouraud, SNA and CLA media. The cultural and morphological characters evaluated were mycelial coloration, size, shape and septation of macro and microconidia, and length and number of phialides. Five species were associated with wilt and/or dry bud rot within three phylogenetic complexes: F. oxysporum of the Fusarium oxysporum species complex (FOSC) with 56% (46.2% soil y 66.7% root) regional representation; F. solani, F. falciforme and Fusarium sp. of Fusarium solani complex (FSSC) (40%); and Fusarium sp. of Fusarium fujikuroi complex (FFSC) (4%). MO and pH correlated inversely with Fusarium Index (r2=0.68- 0.70). It is postulated that wilt and dry bud rot of blue agave constitute a syndrome in which several Fusarium species are associated and parasitically specialized. A single isolate per each species complex was found associated specifically to each or both symptoms. Most isolates were associated to wilting with prevalence of F.oxysporum. [ABSTRACT FROM AUTHOR]

Cercospora agavicola, causal agent of the gray spot of blue agave (Agave tequilana), is a regulated fungus under official control in states under the Denomination of Origin of Tequila (DOT). This work was carried out in Jalisco, Mexico, the main DOT region, to determine the spatial-temporal epidemic inductivity of the fungus and to develop stochastic models to forecast the gray spot in order to support regional preventive programs. Monthly, from October 2016 to December 2017 the severity, incidence and number of diseased plants were evaluated in 41 plots established in commercial agave plantations of 3-4 years of age selected with weighted risk criteria in Los Altos (20), Valleys (11) and South (10). The regional epidemic inductivity of C. agavicola was heterogeneous with a greater risk for at least nine counties of Los Altos. However, low epidemic rates (0.0008-0.006 units week-1), strong restriction spread (1-4 plants), reduced annual increment of incidence (0-32 plants / 0.5 ha) and no spore capture evidenced the low parasitic fitness and reduced fungus epidemic potential. Consequently, limited predictive capacity was found even with the best goodness of fit models (R2 adj 0.51-0.60). The favorable hours (HFav) of January-April, with respect to infection, was consistent among models, so it can be used as preventive algorithm in SIVEA (www.sivea.org.mx). The regional losses were estimated between 237 thousand US dollars and 98.01 MDD. Cercosporin, a toxin associated with Cercospora genus, may be involved in atypical linear temporal progress and should be integrated in future research. [ABSTRACT FROM AUTHOR]

The aim of this study was to estimate yield losses induced by the agent associated with Huanglongbing, Candidatus Liberibacter asiaticus (CLas) in Persian lime (Citrus latifolia Tanaka) in Mexico, by evaluating morphological and organoleptic fruit variables. A four-year old Persian lime orchard in the state of Yucatán, Mexico, was selected; the trees were under same disease management and infection; this feature was verified by qPCR. The study was conducted under four severity levels (0=healthy, 1=25, 2=50, 3=75, 4=100, percentage of canopy with HLB symptoms). Eight morphological and organoleptic variables were evaluated in a restricted random block design with healthy and CLas infected trees. The values of weight, size, skin thickness, juice volume (JV) and pH were statistically higher in fruits from healthy trees as well as in asymptomatic branches of positive trees, in comparison with symptomatic branches (Tukey, P=0.05). CLas induced reduction on weight (17.3%) and JV (18.6%), with more damage in trees showing 100% of canopy with HLB symptoms; the regression models were: Yweight = 217.2-4.2x+0.03x², R²= 0.86; Yvolume = 645.4-11.7x+0.09x², R²= 0.82. The weight reduction implicate a 2.4 tons/ha yield loss. The detrimental effect was associated with severity level and CLas concentration, we found that the intensity of the symptoms of HLB is a function of the bacterial concentration in the model Y[bacteria] = 1.174+0.8x-0.0067x², R² = 0.91. This is the first quantitative study of CLas effects on production of Persian lime. [ABSTRACT FROM AUTHOR]

Objective/Background: Epidemiological research on Phaseolus coccineus is lacking. The aim was to develop and validate digital methods to quantify the severity associated with powdery mildew in ayocote bean. Materials and Methods: An ayocote bean plot with 65.3 % incidence and 22.7 % average powdery mildew foliar severity was selected. Based on 250 leaves collected in field with varying severity degrees, eight 7- and 8-class logarithmicdiagrammatic scales (ELD) were designed and validated in a controlled environment (CEV) and field (FV). In Rstudio®, accuracy (ß), precision (R2), reproducibility (r), and agreement level were determined with Cohen's kappa index (kw) and Lin's concordance coefficient (LCC). Additionally, a Hierarchical Cluster Analysis (HCA) was performed by scale and assessment environment for clustering by similarity evaluation. In ArcMap® v10.3, in a 15-quadrant block, an 'image segmentation' analysis was performed using supervised classification and maximum likelihood to estimate powdery mildew severity and an indicator of canopy coverage index (VCI). Results: In VEC-1, v1r2 (ELD-7c; ß=1.07, R2=0.93, r=0.87) and v1r1 (ELD-8c; ß=0.97, R2=0.85, r=0.87) scales were best evaluated. In VEC-2, comparing clusters conformed in the HCA, the ELD-7c was the best scored with perfect accuracy (ß>0.96), very high precision (R2>0.94), very high reproducibility (r=0.97-0.99) and very high agreement (kw>0.96; LCC>0.97); and in ELD-8c reproducibility and agreement decreased. In VCa, ELD-7c maintained optimal metrics, but ELD- 8c reached ideal parameters for preventive ELD in early stages of powdery mildew (ß>0.98, R2>0.98, r=0.99, kw=0.99-0.999, LCC=0.98-0.999). Image analysis estimated severity = 8.4 % (CI = 5.3 - 12.6 %) and ICV = 0.88 (CI = 0.76 - 0.99), contrasting with field assessment 47 % (CI = 38.8 - 55.3 %) and 0.46 (CI = 0.76 - 0.99), respectively, mainly with ICV > 0.94 due to less symptomatic leaf exposure. Suggests applicability for canopy estimation with restrictions for severity based on pathogen expression. Conclusion: A methodology for ELD development is proposed, comprising: image acquisition, processing and quantification; controlled validation and field validation. Validation statistics included precision (R2); accuracy (ß); reproducibility (Pearson's coefficient and Hierarchical Cluster Analysis); and agreement (Lin's Coefficient and Kappa Index), proposed in a comprehensive approach for first time. RGB-drone images are proposed to estimate a comprehensive vigor and severity coverage index. [ABSTRACT FROM AUTHOR]

Introduction: The US-Mexico region is at high risk of elevated tuberculosis (TB) incidence due to mobility and migration. Knowledge of how socio-demographic factors varies geographically, provides clues to understanding the determinants of tuberculosis and may provide guidance for regional prevention and control strategies to improve public health in Mexico. The aim of the present study was to describe the epidemiologic characteristics and spatial patterns of the incidence of tuberculosis in Tonala, Jalisco (Mexico) from 2013-2015. Methodology: The Surveillance System Database from the Health Department, complemented by information from the National Institute of Statistics and Geography, was used to obtain data for a spatial-temporal analysis of TB cases. For the geographical analysis map creation and geoinformation storing, ArcGIS software was used. Results: This study sought to characterize problem areas and jurisdictional locations of TB via a spatial approach based on analyses of case distributions and individual patient variables. The study found that tuberculosis cases were dispersed throughout Tonala County and were mainly concentrated on the Guadalajara city border. The TB cases were mainly individuals between 31 and 45 years old. Most of the cases reported during the observation period were male patients, and most cases primarily had lung involvement; however, there were quite a few cases with lymph node and intestinal disease. Conclusion: Our findings show that TB cases are essentially located in areas close to the city of Guadalajara and that most TB cases were pulmonary cases spread throughout the whole jurisdiction. [ABSTRACT FROM AUTHOR]

Candidatus Liberibacter asiaticus (CLas), causal agent of Huanglongbing disease (HLB), and the Citrus tristeza virus (CTV) constitute a serious threat to Mexican citriculture because its endemic status in limes in several regions of the Pacific coast and also for the recent detection of severe strains, respectively. The identification and cloning of some genes related to the Systemic Acquired Resistance (SAR) of the plant could help to confront the diseases as an integrated management strategy. This work had the objective of cloning specific genes inherent to the plant as a first step to obtain transgenic citrus plants putatively resistant to CLas. The genes were selected based on the response of citrus plants to a wide range of pathogens, they were; a regulating gene for salicylic acid signaling (SA) as the inducer gen Azelaic Acid Induced 1 (AZI-1), a Citrus Non- Race-Specific Disease Resistance 1 (CsNDR-1) and a pathogenesis related protein 1 gen (PR-1). These three genes (AZI-1, PR-1 and CsNDR-1) were independently inserted into pUC118-FMVPoly- 2-1, subsequently they were subcloned individually into the vector pCAMBIA 2301 while gene AZI-1 was only cloned into pCAMBIA 2201. The CsNDR-1 construct was cloned into Agrobacterium tumefaciens strains EHA5 and AgL1 while genes AZI-1 and PR-1 could not be inserted into these strains of Agrobacterium. These constructions are the first step to be able to generate transgenic citrus as an alternative to face the HLB. [ABSTRACT FROM AUTHOR]

This work had the purpose of detecting the presence of phytoplasmas associated to HLBlike symptoms, a disease caused by CLas, to improve the sampling and detection carryout in official phytosanitary actions in the Mexican citriculture. Base on alerts of negative results to CLas in citrus trees with putative symptoms of HLB, directed samplings were conducted in commercial orchards and country backyards in Hidalgo, Colima, Puebla and Veracruz in 2012, 2013 and 2018. The total DNA was analyzed by PCR with the primers P1 / P7 nested with R16F2 / R16R2 and D7f2 / D7r2. CLas infection was assessed with A2 / J5 primers. The presence of the Brazilian Huanglongbing disease-associated phytoplasma, member of the 16Sr IX group, associated with C. latifolia (NCBI, MK282760) and C. aurantifolia (NCBI, MK282761) was confirmed inducing similar but contrasting symptoms to those caused by CLas. These hosts are reported for the first time in addition to the original report on C. sinensis in Brazil. Bidens odorata and Cajanus cajan are also reported as probable alternate weed hosts as well as the presence of specimens of Graphocephala and Acinopterus (Cicadellidae), genera recognized with vector species of 16Sr III-A and Aster Yellow phytoplasma groups, respectively. [ABSTRACT FROM AUTHOR]

One of the most important phytosanitary problems in two-year plantations of Agave tequilana var. Azul. is agave wilt, that is caused by several organisms, among those pathogens are reported several species of Fusarium and Thielaviopsis pradoxa. The main goal of this research was to introduce beneficial organisms in micropropagation plants as control measure. Inoculated treatments were T1 Trichoderma harzianum (Th), T2 T. virens (Tv), T3 T. aureoviride (Ta), T4 Bacillus subtilis (Bs), T5 Tv + B, Ta + B T6, T7 absolute control (Tabs) and T8 regional control (Treg). Treatments were established in a randomized block design with two replications, the experimental unit (EU) consisted of 122 plants; the minimum sample size was 26 plants. Evaluated variables were colony forming units (CFU) of Trichoderma, Fusarium spp. and Bacillus from roots and substrate and plant height, chlorophyll from plants. Variables were evaluated every 30 days from October 2008 to May 2009. Area under curve (AUC) was calculated for each variable. Our results show that microorganism in the treatments T1, T3, T4 and T6 colonized agave roots and maintain high levels, creating a balance to Fusarium spp. in soil and roots. Under this conditions Fusarium density ranged from 2 to 2.5 log (CFU/mL-1). Analysis of variance did not detect any significant difference among treatments. However, Fusarium spp. density on soil (AUC) was higher in treatments T8 Treg (120) and T7 Tabs (75.75) compared with the rest of treatments (50 or less). Fusarium density on roots was higher on treatments T6 Ta + B (375) and T7 Treg (262.5) compared to T3 Ta (105), T5 Tv + B (187.5), and T1 T4 Th B (210). No significant differences were found on chlorophylls and plant heights. [ABSTRACT FROM AUTHOR]

Objective: Estimate the probabilistic potential of introduction of the causative agent of influenza type A in Mexico, using geo-intelligence applied to health., Methods: Ecological study of 1,973 influenza outbreaks with a high degree of pathogenicity, worldwide during the period 2014-2016. Geospatial modeling was developed with geo-intelligence tools such as spatial representation, a relational model, spatial characterization of the inoculum source with the maximum entropy model and the receiver operating characteristic (ROC) curve, using multicriteria spatial analysis. This was validated with the Moran index and geographically weighted regression., Results: Isochrones (at an initial distance of 548 km) were estimated for health risks and their exponential growth; at the fourth isochrone, the east and west coasts of the United States of America and a part of Central America were identified as possible areas that favor the introduction of the pathogen. Also, a COR curve = 0.923 was obtained; two risk periods for introduction were identified (September-March and April-August, with north-south and south-north trajectories, respectively) with high positive autocorrelation for geospatial modeling; and in one scenario, more than half of Mexico was found to be at high risk of introduction, with an estimated 78 million people exposed. A positive association was identified between significant risk areas ( p < 0.001)., Conclusion: More than 50% of Mexican territory was found to be at risk of introduction of the causative agent of influenza type A, with approximately 70% of the population exposed., Competing Interests: Conflicto de intereses. Ninguno declarado por los autores.