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Background. One of the classic land degradation problems that man has had to face is controlling, preventing, or improving soils affected by salinity. Objective. The objective of this study was to evaluate the physiological and morphometric response of Origanum vulgare L. plants subjected to five concentrations of NaCl (0, 50, 100, 150 and 200 mM NaCl). Methodology. The experiment was established in a completely randomized design with five treatments based on different concentrations of NaCl (0, 50, 100, 150 and 200 mM) with four replications per treatment. Each repetition consisted of 14 plants. The variables evaluated were fresh and dry weight of leaves, leaf area, fresh and dry weight of stem, stem length, fresh and dry weight, and root length, chlorophyll content a and b, relative water content and water potential. Results. The results showed that the fresh and dry weight of leaves, stem and root, foliar area, as well as the length of stem and root showed significant differences between treatments, they decreased as NaCl concentrations increased in the culture medium, as did the chlorophyll content "a and b". It is concluded that oregano plants have the capacity to absorb Na from the culture medium in 50, 100 and 150 mM of NaCl. Implications. The study makes the possibility to determine the tolerance of oregano to salinity, by subjecting the plants to different concentrations of NaCl and assessing whether it has the capacity to absorb Na+ from the culture medium. The study shows that it is possible to grow oregano in floating root hydroponic conditions, considering the advantages that this system offers, such as saving water and nutrients, being possible to obtain adequate yield using water of moderate salinity (50 mM NaCl) that represents an electrical conductivity of 5.8 dS m-1. Conclusions. All variables decreased as NaCl concentrations increased in the culture medium. Oregano showed the ability to absorb Na+ from the culture medium in 50, 100 and 150 mM NaCl.

Background. Salicornia bigelovii (Torr) is a halophyte plant, whose cultivation could be optimized by applying eco-friendly homeopathic treatments, generating new applicable knowledge to reduce saline stress in this and other plant species. Objective. Evaluate physiological response in S. bigelovii plants irrigated with different proportions of seawater (AM), with application of the homeopathic medicine for human use Natrum muriaticum (HOM) in three cultivation periods, considering morphometric variables and chlorophyll content. Methodology. A completely randomized experimental design with factorial arrangement and four repetitions was applied. Factor one corresponded to four different proportions of AM (0, 25, 50 and 100%), factor two, to two HOM dynamizations in 7th and 13th centesimal dilution 1:99 and a control without HOM (NaM-0CH, NaM- 7CH and NaM-13CH) and factor three, at three cultivation periods (1, 2 and 3 months). The morphometric response variables evaluated were plant height (AP), stem thickness (GT), plant cover (CV), number of branches (NR) and chlorophyll content "a", "b" and total. Results. There were significant differences between treatments (p≤0.01). The CV and NR variables were favorably modified when applying NaM-7CH and NaM-13CH (p≤0.01 and 0.001, respectively). The highest AP was obtained with AM-0 / NaM-13CH and the highest GT with AM-50 / NaM-7CH (p≤0.01). The second degree interaction only affected the concentration of chlorophyll "b", with the highest values (p≤0.05) during T-2 with respect to T-1, indistinctly to the application of NaM and AM. The content of chlorophyll "a" and total was reduced with AM-50. Implications. The NaM-AM interaction modified the morphological expression of S. bigelovii (Torr) and the concentration of chlorophyll "a" and total. Conclusion. Positive morphological effects were observed at different salinity levels (% of AM) attributable to HOM treatments, such as higher AP with AM-0 / NaM-13CH and higher GT with AM-50 / NaM-7CH, but inconclusive results for chlorophylls. NaM is an eco-friendly alternative to increase the biomass production of S. bigelovii.

Background. The electrical conductivity (EC) of a nutrient solution (NS) in hydroponic or soilless systems influences the yield and quality of the fruits. Objective. The aim of this research was to determine the quality and fruit yield of bell pepper in response to the electrical conductivity of the nutrient solution. Methodology. A completely randomized experimental design with 15 replications was used. The treatments consisted of four nutrient solutions with different electrical conductivity (1.5, 2.0, 2.5 and 3.0 dS m-1) based on the Steiner nutrient solution. Yield, firmness, and bioactive compounds (phenolic compounds, vitamin C, lycopene, β-carotene, and the antioxidant activity) were quantified in fruits. Results. The results showed that an electrical conductivity of 2.0 dS m-1 or higher increased the bioactive compounds but decreased the yield and firmness of the fruits. Implications. The correct selection of the EC in the NS is a preponderant factor to get functional foods, with high yields and to avoid unnecessary costs in fertilization Conclusion. The high EC in the NS reduced the yield and the firmness of the fruits. From an EC of 2.0 dS m-1 in the NS, the content of vitamin C, total phenols, lycopene, total capsaicinoids, β-carotene and the antioxidant activity of pepper fruits increased.

Background. Mezquite gum (Prosopis laevigata [Humb. & Bonpl. ex Willd.]) is similar to the gum Arabic; its production is associated to the stress condition of the tree. Objective. To induce and evaluate the gum production and quality. Methodology. A completely randomized design with factorial arrangement was used, factor one was seasons (spring and autumn), factor two was tree heights (2.0 and 3.0 m) and factor three was the application of two products, acid 2 -chloroethyl- phosphone (Etherel 240®) + distilled water and a control (distilled water). Results. The gum was produced only in primary branches between 10 and 15 days after applying 2-chloroethyl phosphonic acid + distilled water. Gum production was higher in autumn in 3.0 m trees, with an average of 57 g per tree. A yield of 10.8 kg ha-1 of gum with a density of 190 trees ha-1 was estimated. The content of ash and protein in gum was higher in trees of 2.0 m in autumn, while the content of fiber and nitrogen-free extract in gum was higher in trees of 3.0 m in autumn. The moisture and fat content in gum was higher in spring in trees of 2.0 and 3.0 m, respectively. The pH of the gum was less acid in 3.0 m trees in spring with a lower content of impurities. Implications. It is suggested to carry out other tests to determine the presence of acid 2-chloroethyl-phosphonic in the chemical composition of the gum. Conclusion. The application of acid 2-chloroethyl-phosphonic (20%) + distilled water stimulated gum secretion in mesquite trees. Trees treated with distilled water (control) did not produce gum.

Abiotic stress due to salinity is considered one of the main problems facing agriculture that has the detrimental effect of restricting the growth and development of plants. The objective of this study was to evaluate the effect of arbuscular mycorrhizal fungus species (Rhizophagus fasciculatum) as reliever of NaCl-stress in sweet basil seedlings in emergence stage. A completely randomized design with factorial arrangement with four replications was used; first factor was sweet basil varieties (Nufar, Genovese, and Napoletano), factor two were NaCl concentrations (0, 50, and 100 mM) and factor three was inoculation of seeds with Rhizophagus fasciculatum (+AMF) an arbuscular mycorrhizal fungi and non-inoculated seeds (−AMF). Chemical composition of the substrate, rate and emergence percentage, plant height, root length, fresh and dry biomass of aerial part and root, spore count, and colonization percentage were assessed. The results showed differences in all variables with Napoletano showing higher values of all variables at 0, 50 or 100 mM NaCl with AMF. Majority of variables decreased with NaCl concentrations. The substrate was suitable for growth of Rhizophagus fasciculatum and for sweet basil. No root colonization was found in any seedlings inoculated with AMF; however, the micrograph of the inoculated plants showed vegetative mycelium, a mycorrhizal structure that shows the initiation of the colonization process.

El estudio y desarrollo de recursos vegetales en ambientes áridos-salinos va en aumento. Salicornia bigelovii, es una halófita de gran interés. Sin embargo, la productividad de este tipo de plantas está limitada por la disponibilidad de nitrógeno. Una opción a la fertilización química figuran los microorganismos promotores del crecimiento y las micorrizas. En el presente estudio se evaluó el efecto de Glomus intraradices, tres cepas de rizobacterias (Klebsiella pneumoniae, Bacillus amyloliquefaciens y Azospirillum halopraeferens) y dos tipos de suelos (arcilloso y arenoso) en salicornia, en invernadero. La inoculación de las bacterias bajo condiciones de suelo arenoso estimuló significativamente el crecimiento y factor nutrimental de Salicornia (NPK). Se observó sinergismo entre G. intraradices y las rizobacterias. Al inocularse en forma individual las bacterias, se comportaron con diferencias significativas. Existió sinergismo entre G. intraradices y Klebsiella pneumoniae y A. halopraeferens, en la captación de N; lo contrario ocurrió con G. intraradices y Bacillus amyloliquefaciens con altos valores significativos en la absorción de P y K. El tipo de suelo fue un factor determinante en el comportamiento y en la expresión del beneficio de los microorganismos. Las rizobacterias y micorriza en estudio tienen potencial de uso como promotoras del crecimiento en salicornia.

The improvement, conservation and propagation of Yucca have high perspectives in the North of México; due it is an important ornamental plant, endemic of the Comarca Lagunera. This study was developed in 2007 in natural populations of blue palm (Yucca rigida) in the municipality of Mapimí, Durango, México. The objective was to characterize the habitat and natural populations in different altitude, based on population density and the characteristics of plant height, number of branches, stem diameter, number of fruit per plant, number of seeds per fruit and germination percentage. Results showed that growth of Yucca rigida occurs on superficial soils. It is associated with desert vegetation such as rosetophylla and microphylla, about 1200 to 1300 meter above the sea level. During this study, was found a population density of 890 plants ha-1, and the plant height and stem diameter showed a tendency to increase when the altitude increased.  A low percentage of immature seeds were found, showing that the pollinizer has a good efficiency, moreover offer a high biodiversity of plants, due to the crossed pollination, determining the diversity of population. It is necessary to increase the number of researches to quantify the plant potential and to conservation of genetic variability of this population.

Se determinó el valor nutrimental de alfalfa henificada (AH), dos genotipos de fríjol yorimón [IT90K-277-2 (FYG18) y Sesenteño (FYG25)], un clon de pasto taiwán (PT), un cultivar local de nopal en dos presentaciones, pencas tiernas de 15 días de edad o ";;;nopalitos";;; (NT) y pencas maduras (NM) de 60 días de edad y germinado de semillas de maíz (GM) del genotipo ASGROW 7573. Se cuantificó el contenido de materia seca (MS), proteína cruda (PC), lípidos totales (LT), cenizas (C), fibra cruda (FC) y energía bruta (EB), así como la concentración de ácido linoleico (LA), ácido α-linolénico (ALA), ácidos grasos poliinsaturados (PUFA) y ácidos grasos n-3. Los resultados revelan que los genotipos de frijol yorimón FYG25 y FYG18, mostraron el mayor contenido de PC. Respecto a la concentración de LT, el genotipo de yorimón FYG25 mostró la mayor cantidad seguido del FYG18 y AH. Los forrajes verdes de frijol yorimón (FYG25 y FYG18), así como el pasto Taiwán tuvieron el contenido mayor de ácido α-linolénico. Las semillas de germinado de maíz mostraron los contenidos mayores de ácido linolénico seguido del nopal tierno. Ambos ácidos grasos poliinsaturados (ALA y LA) son precursores del ácido ruménico y del ácido vaccénico en rumiantes. Por lo tanto, el uso de estos forrajes verdes en la alimentación de rumiantes es una alternativa que podría modificar las proporciones de ácido grasos en la leche y la carne con el propósito de incrementar los PUFA, específicamente el ácido ruménico así como el ácido vaccénico.

A nivel mundial la papa junto con el arroz, el maíz y el trigo, constituyen los cuatro cultivos más importantes para la alimentación humana. En años recientes se ha detectado en algunas regiones de Estados Unidos (EUA) y Canadá, la bacteria Clavibacter michiganensis ssp sepedonicus (Cms) la cual provoca la enfermedad denominada podredumbre anular (PA) en el cultivo de papa. Esta bacteria ocasiona una pudrición en el tubérculo, tallos y hojas de este cultivo y tiene la particularidad de diseminarse por semilla. Dada la cercanía con los EUA y Canadá, y siendo México un país importador de semilla de esos países, las probabilidades de una eventual introducción de esta enfermedad son significativas, especialmente en áreas con amplias extensiones de papa. El estado de Sonora es una de las regiones más importantes en relación a la producción de papa y otros cultivos en México. Por lo anterior, se realizó la presente investigación, teniendo como objetivos conocer la situación actual de Cms en las zonas agrícolas donde se desarrolla el cultivo de papa en el estado de Sonora, en material vegetativo de importación y aquel de procedencia nacional considerado semilla por los productores. La investigación se llevó acabo en la Universidad de Sonora, Campus Santa Ana; el desarrollo del estudio consistió en la obtención de semilla procedente del extranjero y aquella nacional que utilizan algunos productores paperos para su siembra. Asimismo se desarrolló una toma de muestra vegetativa en las etapas de plántula, floración y madurez fisiológica. Para su diagnóstico se consideraron medios específicos, conjugación de anticuerpos específicos con la bacteria en estudio, formación de capas de inmunocomplejos, revelados enzimáticos y pruebas de patogenicidad. Los resultados muestran positiva la presencia de Cms en tubérculo de consumo (Navojoa, Hermosillo y Agua Prieta) mientras que en aquella de importación los resultados indican negativa su presencia. En las etapas vegetativas de plántula, floración y fructificación y aquella semilla de origen extranjero resultó ser nulo su diagnóstico.

Los alimentos orgánicos son producidos mediante prácticas que promueven la fertilidad del suelo y la diversidad biológica, y excluyen todos aquellos productos químicos que se usan en la agricultura convencional. En regiones aisladas este tipo de producción no presenta serios inconvenientes, ya que el mismo sistema protege los cultivos de altos niveles de plagas y enfermedades. La demanda de alimentos orgánicos se ha incrementado desde hace dos décadas, por lo que producir en baja escala y en forma aislada no puede satisfacer los requerimientos del mercado. Esta demanda se ha convertido en una oportunidad de desarrollo importante en varios países. En superficies mayores tienden a aumentar las poblaciones de plagas y enfermedades, por lo que es necesario implementar actividades que ayuden al sistema a reducir dichas poblaciones. Este tipo de agricultura permite el control biológico, cultural, mecánico y físico, aunque su utilización la limitan los estándares y reglamentos señalados por las agencias certificadoras. Los productores deben determinar el manejo óptimo de plagas mediante estrategias que estén consideradas dentro del ambiente regulatorio del movimiento orgánico. Se presentan algunas alternativas adecuadas para implementar un programa de manejo, con un enfoque que considera la regulación actual para lograr y no poner en riesgo de pérdida, la certificación como productor orgánico.