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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.

The fruit of 18 Solanum lycopersicum var. cerasiforme accessions from Mexico were evaluated for total phenolics (TP) by the Folin-Ciocalteau assay, phenolic profiles by high performance liquid chromatography-diode array detection-mass spectrometry (HPLC-DAD-MS), antioxidant activity (AoxA) by 2,2´-azino-bis(3-ethylbenzothiazolin)-6-sulfonic acid (ABTS), 2,2-diphenil-1-pycrilhydrazyl (DPPH), and oxygen radical absorbance capacity (ORAC), and antimutagenic activity (AmuA) by the Ames assay. TP was measured as Gallic Acid Equivalents (GAE) and the AoxA as Trolox Equivalents (TE). TP varied from 37 to 86 mg GAE 100 g−1 fresh weight (fw). The AoxA by ABTS (568-1187 µmol TE 100 g−1 fw) and DPPH (157-350 µmol TE 100 g−1 fw) correlated with TP and the levels of caffeoylquinic acids and rutin. The AmuA did not correlate with the levels of phenolics. Some accessions had higher AoxA and AmuA than those reported for commercial cultivars and also showed high levels of caffeoylquinic acids and rutin; thus, their consumption could have good health promoting effects.

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 identif icación de razas f isiológicas 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.

Anthracnose of papaya fruit caused by the fungus Colletotrichum gloeosporioides is one of the most economically important postharvest diseases. Hot water immersion (HW) and calcium chloride (Ca) treatments have been used to control papaya postharvest diseases; however, the effect of the combination HW-Ca on the pathogen growth and the development of the disease in infected papaya fruit has been scarcely studied. The aim of this study was to evaluate the effect of the HW-Ca treatment on the in vitro growth of C. gloesporioides conidia and the quality of infected papaya. In vitro, the HW-Ca treated conidia showed reduced mycelial growth and germination. In vivo, the HW-Ca treatment of infected papaya delayed for 5 days the onset of the anthracnose symptoms and improved the papaya postharvest quality. The combined treatment HW-Ca was better than any of the individual treatments to inhibit the in vitro development of C. gloeosporioides and to reduce the negative effects of papaya anthracnose.

In this research, a healthy ready-to-eat expanded snack was produced using a maize/common bean (70/30%) mixture and characterized for its nutritional value, antioxidant potential, and phytochemical composition. Free and bound extracts were obtained and analyzed for phenolic profiles by ultra-high performance liquid chromatography with diode-array detector–tandem mass spectrometry (UPLC-DAD-MSn) and antioxidant activity (IC50) by ABTS and DPPH methods. Fatty acids and amino acid profiles were obtained by gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC), respectively. Fourteen phenolic compounds were identified and quantified (mg/100 g, dw); the main compounds included three phenolic acids (ferulic, diferulic, p-coumaric) and three flavonoids (naringenin, kaempferol, methyl isoflavone). The IC50 (mg/mL) values obtained by ABTS (4.17 and 0.12) were smaller than those measured by DPPH (5.93 and 0.33). Seven fatty acids were also identified and the two most abundant were unsaturated (oleic, linoleic). The snack also showed an acceptable balance of amino acids according to the FAO, 2013 requirements, as well as a chemical score = 74.09 in vitro protein digestibility = 77.21%, C-PER = 1.53 and PDCAAS = 57.20%. The expanded snack could be source of bioactive, nutritional and antioxidant compounds for the improvement of the consumer's health.

"La variación genética de maíz (Zea mays ssp. mays L.) en México ha sido estudiada especialmente en el centro-sur del país. El estado de Sinaloa (primero en producción) posee 23% de la variación genética racial nacional, pero su evaluación es escasa. Recolectamos 144 muestras de maíz (Tuxpeño Norteño, Vandeño, Onaveño, Elotero de Sinaloa, Tabloncillo, Tabloncillo Perla, Bofo, Jala, Blando de Sonora, Chapalote, Dulcillo del Noroeste y Reventador) en distintos puntos del estado con el objetivo de describir las características morfológicas y agronómicas relevantes para determinar un patrón de agrupación. Las accesiones fueron evaluadas en dos ambientes con un diseño de látice simple 12×12, analizando 27 variables. El ANDEVA detectó diferencias significativas entre accesiones (todas las variables), interacción genotipo × ambiente (anchura/longitud del grano) y ambientes en la espiga (longitud del tramo ramificado, número de ramificaciones primarias y longitud de la rama central), mazorca (diámetro/longitud, longitud del pedúnculo y de mazorca) y grano (volumen y peso/volumen). Los tres primeros componentes principales (CP) explicaron 64% de la varianza, donde las variables: número de hojas, diámetro y longitud de la mazorca; la anchura y espesor de grano; anchura/longitud del grano y floración; son las más importantes. La representación gráfica de los CP1 y CP2 reveló seis grupos y la de conglomerados cinco. Algunas accesiones poseían características compartidas con más de un grupo racial y su posición fue cercana a la de quienes compartían características. Se confirma una amplia diversidad genética de maíces nativos en Sinaloa."

The majority of snacks expanded by extrusion (SEE) are made with vegetable sources, to improve their nutritional content, it has been proposed to incorporate squid (Dosidicus gigas), due to its high protein content, low price and high availability. However, the interaction of proteins of animal origin with starch during extrusion causes negative effects on the sensory properties of SEE, so it is necessary to know the type of protein–carbohydrate interactions and their effect on these properties. The objective of this research was to study the interaction of proteins and carbohydrates of SEE elaborated with squid mantle, potato and corn. The nutritional composition and protein digestibility were evaluated, Fourier transform infrared (FTIR) and Differential Scanning Calorimetry (DSC) were used to study the formation of protein–starch complexes and the possible regions responsible for their interactions. The SEE had a high protein content (40–85%) and biological value (&gt, 93%). The melting temperature (Tm) was found between 145 and 225 °C, the Tm values in extruded samples are directly proportional to the squid content. The extrusion process reduced the amine groups I and II responsible for the protein–protein interaction and increased the O-glucosidic bonds, so these bonds could be responsible for the protein–carbohydrate interactions.

Echeveria species (Crassulaceae) are used in traditional medicine and some of their biological activities are demonstrated (e.g. antimicrobial, anti-inflammatory, anticancer). However, their chemical composition has been scarcely studied. The methanol extracts (ME) of three Echeveria species (E. craigiana, E. kimnachii and E. subrigida) from Mexico were analyzed for the sterol (GC-MS) and phenolic (HPLC-DAD-ESI-MSn) composition. Eleven sterols were identified, E. kimnachii showed the highest total content (7.87 mg/g ME), and the main constituents were γ-sitosterol in E. craigiana (33.9%) and E. subrigida (54.4%), and lupenone in E. kimnachii (28.9%). The phenolic analysis showed differences among the Echeveria species, which contained flavonoids derivatives and tannins as the main components. The main flavonoids in E. craigiana were hexoside derivatives of quercetin and isorhamnetin, both with a 3-hydroxy-3-methylglutaroyl substituent; in E. subrigida hexosides of isorhamnetin, quercetin and kaempferol; and E. kimnachii showed the greatest diversity including proanthocyanidins and less common flavonoid derivatives of kaempferol O,O-disubstituted by acyl derivatives. The characteristic phytochemicals of each studied Echeveria species could be responsible of its specific biological activities and useful as chemotaxonomic markers. The kaempferol derivatives in E. kimnachii are rare in nature and they will be isolated and characterized., Journal of Applied Botany and Food Quality, Vol 91 (2018): Journal of Applied Botany and Food Quality

Context:Helicteres vegae Cristóbal (Sterculiaceae) (Hv) and Heliopsis sinaloensis B.L. Turner (Asteraceae) (Hs) are endangered and poorly studied plant species; related plants have been used against chronic-degenerative and infectious diseases. Therefore, Hv and Hs could be sources of bioactive compounds against these illnesses. Objective: To determine the chemical composition and biological activities (antioxidant, antimutagenic and antimicrobial) of Hv and Hs leaves (L) and stems (S). Materials and methods: Methanol extracts (ME) of each plant/tissue were evaluated for their phytochemicals; phenolics (HPLC-DAD-ESI-MS); antioxidant activity (AA) (0.125–4 mg/mL) (DPPH, ABTS, ORAC and β-carotene discoloration); antimutagenicity (0.5 and 1 mg/plate) (Ames assay, tester strain Salmonella enterica serovar Typhimurium YG1024, 1-nitropyrene as mutagen); activity against human pathogens (1 mg/mL); and toxicity (0.01–2 mg/mL) (Artemia salina assay). Results: All ME showed flavonoids and triterpenes/steroids. The ME-SHv had the highest content of total phenolics (TP) (2245.82 ± 21.45 mg GAE/100 g d.w.) and condensed tannins (603.71 ± 1.115 mg CE/100 g d.w.). The compounds identified were flavonoids (kaempferol 7-O-coumaroylhexoside, and two kaempferol 7-O-rhamnosylhexosides) and phenolics [rosmarinic acid, and 3′-O-(8″-Z-caffeoyl) rosmarinic acid]. The ME-LHs showed the highest content of flavonoids (357.88 mg RE/g d.w.) and phenolic acids (238.58 mg CAE/g d.w.) by HPLC. The ME-SHv showed the highest AA. All ME were strong antimutagens (63.3-85.7%). Only the Hs extracts were toxic (ME-LHs, LC50 = 94.9 ± 1.7 μg/mL; ME-SHs, LC50 = 89.03 ± 4.42 μg/mL). Discussion and conclusions: Both Hv and Hs are potential sources of preventive and therapeutic agents against chronic-degenerative diseases.

In the state of Sinaloa Mexico, traditional farmers still cultivate maize accessions with a wide diversity of morphological characteristics, but the gene reservoir maintained in these populations has been poorly studied and it is being lost due to changes in land use and the adoption of hybrid commercial varieties. The aim of this study was to evaluate the genetic diversity of some of these maize populations to contribute to their preservation. Twenty eight accessions were used for the analysis. DNA was extracted from 396 individuals and probed with 20 microsatellites distributed across the maize genome. A total of 121 alleles were obtained (average of 6.1 alleles per locus) and a total genetic diversity of 0.72. The UPGMA-cluster analysis, model-based population structure and principal component analysis revealed three major groups, one formed mainly by accessions of races typical of the Northwestern lowlands (Chapalote, Dulcillo del Noroeste, Tabloncillo Perla, Blando de Sonora and Elotero de Sinaloa) and the other two with accessions mainly from Tabloncillo and Tuxpeno. The high number of alleles per locus and total genetic diversity found in this study demonstrate a broad genetic basis of the accessions of maize landraces from Sinaloa, representing a gene reservoir useful in breeding programs.

In Mexico, common bean grain has been used for centuries in Mexican population diet. The organoleptic and nutritional properties and other characteristics are related to protein composition. Proteomics approaches have been employed to detected genetic variation of soybean and other crops, but there is not a report of this technologies applied to common beans. The proteomics characterization of three genotypes of common bean produced in Sinaloa was realized. The genotypes: Azufrado Higuera, Azufrado Noroeste and Azufrado Regional 87 were evaluated. A protein extraction protocol based on TCA/acetone precipitations was optimized in order to perform Twodimensional gel electrophoresis. Gels analysis shown significant differences between all the genotypes, but a strong homology was detected between Azufrado Higuera and Azufrado Noroeste seed storage proteins, but not with Azufrado Regional 87. These results are the first attempt to employ proteomics technique to common beans studies.

Tomato (Solanum lycopersicum) fruit is susceptible to chilling injury (CI), a physiological disorder caused by low, non-freezing temperatures that affects fruit postharvest quality. Little is known about the biochemical basis of CI, and the aim of this study was to identify proteins related to this disorder in ‘Imperial’ tomato fruit. CI and protein expression changes were analyzed during fruit ripening (0, 4, 8, and 12 days at 21 °C) after storage under chilling (5 °C) and non-chilling conditions (21 °C) for 5, 15, and 25 days. The main CI symptoms observed were uneven fruit ripening and color development, pitting, and decay. Protein analysis of two-dimensional gels showed that 6% of the detected spots (≈300) changed their expression in response to cold. The identified proteins are involved in carbon metabolism, oxidative stress, photosynthesis, and protein processing and degradation; two were related to cold stress, showing higher accumulation in non-damaged tissue of chilled fruit: thioredoxin peroxidase (TPxI) and glycine-rich RNA-binding protein (GR-RBP). This is the first report suggesting an important role for TPxI and GR-RBP in cold response during tomato fruit ripening, and they may be acting through redox sensing and regulation of gene expression at low temperature. These enzymes and the other chilling-related proteins might be working together to maintain the cellular homeostasis under cold stress conditions.

Waxed and nonwaxed mature green tomato fruits were stored at 12C (nonchilled) or 5C (chilled) for 5, 10, 15 and 20 days before being transferred to 22C for 3, 6, 9 and 12 days, were evaluated for weight loss, chemical composition, skin color, chilling injury (CI) index and pigment content. Waxed fruits showed a delay in weight loss, color development and ripening. The sensitivity of tomato fruit to CI was reduced in waxed fruits, which showed a delay in the appearance of symptoms. A delay in chlorophyll degradation and lycopene synthesis was observed as a result of the use of wax and low temperature. Waxing of tomato fruits allowed their storage at temperatures below critical reducing CI sensitivity and maintaining quality giving more time for marketing. PRACTICAL APPLICATIONS Nowadays, local tomato producers use wax on fruits as an everyday practice to carry postharvest fungicides and to improve brightness. They store tomato fruits at nonchilling temperature (12C) because lower temperatures would cause chilling injury and irregular ripening. In this way, it is interesting that waxing tomato fruits allow reducing their storage temperature, protecting them from chilling injury and maintaining their quality and correct color change and ripening; thereby producers and sellers have more days to position their fruits with no extra cost.

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.

Leishmanisis is a parasitic diseases caused by intracellular protozoan of Leishmania genus. These parasites are transmitted by the bite of phlebotomine flies. Leishmanises are classified in different clinic variants: cutaneous localized or diffuse, mucocutaneous and visceral. In Mexico, the leishmanisis are distributed in several states, however Durango was considered free of leishmaniasis.A 9 year old male patient with an ulcerated pruriginous node of circular shape, 13 x 18 mm diameter, localized in the back of the right arm with 6 months progression. The patient was a permanent resident of Durango, Mexico. Histopathology evidenced macrophages infected with amastigotes. The PCR-RFLP result was consistent with Leishmania mexicana. Treatment with glucantime was satisfactory.Here we report the first clinical case of leishmanisis cutaneous localized caused by Leishmania mexicana from Durango, Mexico in a 9 years old male, confirming the increasing propagation of this protozoan parasite in Mexico.

The Mexican fruit fly, Anastrepha ludens Loew (Diptera: Tephritidae), is one of the most harmful pests of mango causing direct damage by oviposition on the fruit pulp. Mango for export is subjected to hydrothermal treatment as a quarantine method for the control of this pest, but exposure to heat for long periods of time reduces considerably the quality and shelf-life of treated fruit. The aim of this work was to study morphological changes of third-instar larvae and adults of A. ludens after in vitro exposure to high temperature at sublethal times. A heating block system was used to expose larvae at 46.1°C for 19.6 and 12.9 min, producing 94.6 and 70% mortality, respectively. Treated larvae were processed for optical microscopy. A fraction of surviving treated larvae was separated into containers with artificial diet to allow development into adults. Adult sexual organs were dissected and processed for transmission electron microscopy analysis. Results showed that 94.6% of the treated larvae died at 46.1°C for 19.6 min and none of the surviving larvae eclosed to adulthood, as they developed as malformed puparia. For the in vitro treatment at 46.1°C during 12.9 min, 70% of the treated larvae died and only 3.75% reached the adult stage, but ultrastructural damage in the male testes and in the female ovaries was observed. Additionally, 11.1% of the adult flies from the in vitro treatment also showed wing malformation and were incapable of flying. The analysis showed that surviving flies were unable to reproduce.

The pulp of the Vitex mollis fruit is edible and traditionally used to treat diarrhoea. The antibacterial activity of this fruit is reported here for the first time. The fruit pulp was extracted with methanol (ME) and the extract was fractionated with solvents. ME and their fractions [hexanic (HF), chloroformic (CF), ethyl acetate (EAF) and aqueous (AqF)] were assayed against human pathogenic bacteria (microdilution test) and their phytochemicals determined (qualitative chemical determinations). The samples (i.e., ME, HE, CF, EAF and AqF) showed antibacterial activity; EAF was the most active, showing such activity against Shigella dysenteriae [minimal inhibitory concentration (MIC)=2 mg/ml]. Phenolics were mainly found in ME and EAF; compounds of this chemical family are well known for their antidiarrhoeal and antimicrobial activities. The reported antibacterial activity and phenolics content of V. mollis fruit could be associated with its use in the treatment of diarrhoea. Key words: Antibacterial activity, diarrhoea, phytochemical analysis, Vitex mollis

A simplified protocol to obtain transgenic tomato plants was established. The effects of culture media composition and Agrobacterium concentration were evaluated. The highest shoot-forming capacity index (5.6) was observed when leaf explants were cultured for 6 weeks with 2 mg·L−1 zeatin, 0.1 mg·L−1 indoleacetic acid, and 300 mg·L−1 timentin. Shoot elongation and root formation were performed in one step on growth regulator-free media. The highest percentage (82%) of fully developed plantlets was obtained when shoots were cultured for 4 weeks with 0.5× Murashige and Skoog (MS) media and 15 g·L−1 sucrose. A 100% of plant survival rate was observed after 4 weeks of being transplanted to ex vitro conditions followed by fruit production (15 fruits/plant) after 2 more weeks. Transient expression of β-glucuronidase was visualized in 100% of the leaf explants infected with Agrobacterium at an OD600 = 0.5 and cocultured for 48 h with 2 mg·L−1 benzylaminopurine, 0.1 mg·L−1 naphthaleneacetic acid, and 100 μM acetosyringone. Stable transformation was confirmed by histochemical glucuronidase assay and polymerase chain reaction (PCR) analysis with a total efficiency of 19.1%. The complete protocol, from shoot induction to fruit production of soil-adapted transgenic plants can be accomplished in only 4 months, and it seems to be very useful for both micropropagation and genetic transformation purposes.