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The “permanent tomato”, “spotted tuber”or “zebra chip”in potato and “chlorotic buds”of chili, are three diseases described in Mexico with coincidental signs of flower abortion, obscuration of vascular tissue at the base of the stem and root of the plants. The association between these diseases and the emerging bacterium Candidatus Liberibactersolanacearum(CLs) as well as the psyllid Bactericera cockerelli as its vector has been mentioned. These diseases, which were initially located in three states of Mexico, have spread to the main Solanaceae producing regions, both in field conditions and in the greenhouse. The objective of the study was to know the presence of CLs associated with diseases that affect the tomato, para and chilicrops in Mexico. The bacterium was identified by PCR of the 16S rDNA gene, cloning and sequencing. The alignment of nucleotide sequences was performed with the Clustal W method and the phylogenetic tree was built with the Neighbor-Joining algorithm from distances calculated with the Tajima-Nei method and a Felsenstein index of 1000 replicas, using the software MEGA version 5.05. A total of 167 samples were analyzed, of which 86 were positive, from 14 states of Mexico. Five nucleotide sequences from Guanajuato, San Luis Potosiand Sinaloa corresponding to tomato, potato and chili, adults and eggs of B. cockerelli were obtained. The analysis of the sequences showed an identity of 99.4%when compared between these and up to 99.8% with GenBank accessions described for CLs in the USA, New Zealand and Canada. Keywords: chlorotic buds, tomato permanent, zebra chip, El “permanente del tomate”, “manchado del tubérculo” o “zebra chip” en papa y “brotes cloróticos” del chile, son tres enfermedades descritas en México con signos coincidentes de aborto de flor, oscurecimiento de tejido vascular en la base del tallo y raíz de las plantas. Se ha mencionado la asociación entre estas enfermedades y la bacteria emergente Candidatus Liberibacter solanacearum (CLs) así como al psílido Bactericera cockerelli como su vector. Estas enfermedades, que en inicio se localizaban en tres estados de México se han diseminado a las principales regiones productoras de solanáceas, tanto en condiciones de campo como en invernadero. El objetivo del estudio fue conocer la presencia de CLs asociado a enfermedades que afectan los cultivos de tomate, para y chile en México. La bacteria se identificó por PCR del gen 16S de ADNr, clonación y secuenciación. La alineación de secuencias nucleotídicas se realizó con el método Clustal W y el árbol filogenético se construyó con el algoritmo de Neighbor-Joining a partir de distancias calculadas con el método de Tajima-Nei y un índice de Felsenstein de 1 000 réplicas, utilizando el software MEGA versión 5.05. En total se analizaron 167 muestras, de las cuales 86 resultaron positivas, provenientes de 14 estados de México. Se obtuvieron cinco secuencias nucleotídicas de Guanajuato, San Luis Potosí y Sinaloa correspondientes al tomate, papa y chile, adultos y huevecillos de B. cockerelli. El análisis de las secuencias mostró una identidad de 99.4% al comparase entre estas y hasta 99.8% con accesiones del GenBank descritas para CLs en EUA, Nueva Zelanda y Canadá. Palabras clave: brotes cloróticos, permanente del tomate, zebra chip

In country, non-target arthropod (NTA) field evaluations are required to comply with the regulatory process for cultivation of genetically modified (GM) maize in Mexico. Two sets of field trials, Experimental Phase and Pilot Phase, were conducted to identify any potential harm of insect-protected and glyphosate-tolerant maize (MON89Ø34-3 × MON-88Ø17-3 and MON-89Ø34-3 × MON-ØØ6Ø3-6) and glyphosatetolerant maize (MON-ØØ6Ø3-6) to local NTAs compared to conventional maize. NTA abundance data were collected at 32 sites, providing high geographic and environmental diversity within maize production areas from four ecological regions (ecoregions) in northern Mexico. The most abundant herbivorous taxa collected included field crickets, corn flea beetles, rootworm beetles, cornsilk flies, aphids, leafhoppers, plant bugs and thrips while the most abundant beneficial taxa captured were soil mites, spiders, predatory ground beetles, rove beetles, springtails (Collembola), predatory earwigs, ladybird beetles, syrphid flies, tachinid flies, minute pirate bugs, parasitic wasps and lacewings. Across the taxa analysed, no statistically significant differences in abundance were detected between GM maize and the conventional maize control for 69 of the 74 comparisons (93.2%) indicating thatthe single or stacked insect-protected and herbicide-tolerant GM traits generally exert no marked adverse effects on the arthropod populations compared with conventional maize. The distribution of taxa observed in this study provides evidence that irrespective of variations in overall biodiversity of a given ecoregion, important herbivore, predatory and parasitic arthropod taxa within the commercial maize agroecosystem are highly similar indicating that relevant data generated in one ecoregion can be transportable for the risk assessment of the same or similar GM crop in another ecoregion.

The effects of ultrasound-assisted extraction (UAE) at different ultrasound power densities (UPDs; 40, 80, and 120 mW/mL) and solid:liquid (S:L) ratio (1:2, 1:3, and 1:6) on the extraction of carbohydrates from Agave tequilana plant of different ages were evaluated. Extracts obtained (6- and 7-year-old plant) were analyzed in the yield of carbohydrates (YC), fructan (FRU) content, simple sugars, fructan profile and the average degree of polymerization (DPn). UPD, S:L ratio, and plant age all affected YC, FRU, and DPn. Maximum YC and FRU were obtained from the older agave with UPD and S:L ratio of 120 mW/mL and 1:6, respectively; while glucose, fructose, and sucrose were highly released from the younger plant. Agave of 7-year-old presented the highest DPn. Fructan degradation occurred at high UPD, increasing the simple sugars and decreasing the DPn. Thermal-traditional extraction without sonication caused more fructan degradation; and overall, ultrasound enhanced fructan extraction and minimized fructan damage, representing a technological alternative for fructan extraction from agave. Keywords: agave; fructans; ultrasound; power density; solid:liquid ratio; plant age. Practical Application: Agave tequilana Weber var. azul plants have significant amounts of fructans. Extraction of these components by alternative methods such as ultrasound could represent advantages, improving the extraction and product quality. This research presents an alternative for the extraction of fructans assisted with ultrasound, evaluating different powers and solid-liquid ratios from agave heads of two different ages. Both variables, as well as age of agave showed a strong effect on fructan extraction. Ultrasound enhanced the extraction and minimized fructan damage, representing a technological alternative.

Environmental risk assessment (ERA) of genetically modified (GM) crops is a process to evaluate whether the biotechnology trait(s) in a GM crop may result in increased pest potential or harm to the environment. In this analysis, two GM insect-resistant (IR) herbicide-tolerant maize hybrids (MON-89Ø34-3 9 MON-88Ø17-3 and MON-89Ø34-3 9 MON-ØØ6Ø3-6) and one herbicide-tolerant GM hybrid (MON-ØØ6Ø3-6) were compared with conventional maize hybrids of similar genetic backgrounds. Two sets of studies, Experimental Phase and Pilot Phase, were conducted across five ecological regions (ecoregions) in Mexico during 2009–2013, and data were subject to meta-analysis. Results from the Experimental Phase studies, which were used for ERA, indicated that the three GM hybrids were not different from conventional maize for early stand count, days-tosilking, days-to-anthesis, root lodging, stalk lodging, or final stand count. Statistically significant differences were observed for seedling vigor, ear height, plant height, grain moisture, and grain yield, particularly in the IR hybrids; however, none of these phenotypic differences are expected to contribute to a biological or ecological change that would result in an increased pest potential or ecological risk when cultivating these GM hybrids. Overall, results from the Experimental Phase studies are consistent with those from other world regions, confirming that there are no additional risks compared to conventional maize. Results from Pilot Phase studies indicated that, compared to conventional maize hybrids, no differences were detected for the agronomic and phenotypic characteristics measured on the three GM maize hybrids, with the exception of grain moisture and grain yield in the IR hybrids. Since MON-89Ø343 9 MON-88Ø17-3 and MON-89Ø34-3 9 MONØØ6Ø3-6 confer resistance to target insect pests, they are an alternative for farmers in Mexico to protect the crop from insect damage. Additionally, the herbicide tolerance conferred by

Fusarium oxysporum f. sp. ciceris (Foc) is a phytopathogenic fungus that causes the disease known as Fusarium wilt in chickpea cultivation. In Mexico, chickpea export only grown in the Northwest (Sinaloa, Sonora and Baja California Sur). Considering that Foc limits the production of this crop and no information concerning the identification of physiological races of this fungus in Mexico, the goal was to isolate and identify by molecular and biological tests physiological races of the fungus present in the growing areas chickpea in the northwest region of Mexico. During the period 2010-2014 were collected chickpea plants with symptoms of wilting and yellowing at different locations in the States of Sinaloa, Sonora and Baja California Sur. The fungus was isolated from small portions of the plant, which were seeded in medium potato-dextrose agar culture medium supplemented with pentanitroclorobenceno (PCNB) and chloramphenicol. We isolated and purified spore cultures, DNA was extracted for identification of physiological races by PCR and enzymatic sequencing. These strains were inoculated into chickpea in differential lines, confirming Mexico for the first time the identification of physiological races Foc 0 and 5., Fusarium oxysporum f. sp. ciceris (Foc) es un hongo fitopatógeno que causa la enfermedad conocida como fusariosis vascular en el cultivo del garbanzo. En México, el garbanzo para exportación sólo se cultiva en el Noroeste (Sinaloa, Sonora y Baja California Sur). Considerando que Foc limita la producción de este cultivo y que en México no existe información referente a la identificación de las razas fisiológicas de este hongo, el objetivo fue aislar e identificar mediante pruebas moleculares y biológicas las razas fisiológicas del hongo presentes en las zonas de cultivo de garbanzo de la región del noroeste de México. Durante el periodo 2010-2014 se colectaron plantas de garbanzo con síntomas de marchitez y amarillez en diferentes localidades de los estados de Sinaloa, Sonora y Baja California Sur. El hongo se aisló a partir de pequeñas porciones de la planta, los cuales fueron sembradas en medio de cultivo papa-dextrosa-agar suplementado con pentanitroclorobenceno (PCNB) y cloranfenicol. Se aislaron y purificaron cultivos monospóricos, a los cuales se les extrajo el ADN para la identificación de razas fisiológicas mediante PCR y secuenciación enzimática. Estas cepas se inocularon en líneas diferenciales de garbanzo, confirmándose por primera vez en México la identificación de las razas fisiológicas 0 y 5 de Foc.

Mexico, the center of origin of maize (Zea mays L.), has taken actions to preserve the identity and diversity of maize landraces and wild relatives. Historically, spatial isolation has been used in seed production to maintain seed purity. Spatial isolation can also be a key component for a strategy to minimize pollen-mediated gene flow in Mexico between transgenic maize and sexually compatible plants of maize conventional hybrids, landraces, and wild relatives. The objective of this research was to generate field maize-to-maize outcrossing data to help guide coexistence discussions in Mexico. In this study, outcrossing rates were determined and modeled from eight locations in six northern states, which represent the most economically important areas for the cultivation of hybrid maize in Mexico. At each site, pollen source plots were planted with a yellow-kernel maize hybrid and surrounded by plots with a white-kernel conventional maize hybrid (pollen recipient) of the same maturity. Outcrossing rates were then quantified by assessing the number of yellow kernels harvested from white-kernel hybrid plots. The highest outcrossing values were observed near the pollen source (12.9% at 1 m distance). The outcrossing levels declined sharply to 4.6, 2.7, 1.4, 1.0, 0.9, 0.5, and 0.5% as the distance from the pollen source increased to 2, 4, 8, 12, 16, 20, and 25 m, respectively. At distances beyond 20 m outcrossing values at all locations were below 1%. These trends are consistent with studies conducted in other world regions. The results suggest that coexistence measures that have been implemented in other geographies, such as spatial isolation, would be successful in Mexico to minimize transgenic maize pollen flow to conventional maize hybrids, landraces and wild relatives.