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The establishment of Pachycereus pringlei seedlings is a scarce event; soil conditions are one of the factors attributed to its high mortality rate in the early stages of development. The use of organic manures as a substrate helps to improve the structure, porosity, and density of the soil where they live, in addition to providing nutrients that would benefit the roots, increasing the possibility of their establishment during the emergence stage. The objective of this study was to evaluate the effect of different proportions of organic manures as a sown substrate in the emergence and establishment of Pachycereus pringlei seedlings, using nine treatments of organic manures in a completely randomized experimental design with four replications. The variables measured were emergence rate (ER) and percentage (EP) and their indices, seedlings’ morphometric, and physiological characteristics in the establishment stage. The results showed that the evaluated variables in the emergence and seedling establishment phase indicate the preference for natural substrate and organic manure combinations in proportions of 50 and 30%, respectively. The analysis of variance showed significant differences regarding the morphometric and physiological variables of the stem and root of the evaluated treatments. The emergence and establishment analyses show that cardon seedlings under different organic manure treatments and controlled conditions had excellent survival results compared to the low rates of recruitment and survival reported under natural conditions. Similarly, the implementation of organic manures improved the physiological and morphometric characteristics of the cardon seedlings compared to the control treatment with the natural substrate.

Salicornia bigelovii (Torr.) es una planta con un promisorio potencial agroindustrial y la homeopatía es una alternativa natural que no afecta la inocuidad del organismo tratado. El objetivo del estudio fue evaluar el efecto del medicamento homeopático Natrum muriaticum (NaM) sobre variables de respuesta productiva de S. bigelovii con diferentes niveles de salinidad (NS) en cultivo hidropónico, aplicando un diseño experimental completamente al azar, con arreglo factorial (3A x 3B) y tres repeticiones de 15 plantas c/u. Como factor A, se aplicaron dos niveles de salinidad (NS-50 y NS-100) y un control sin salinidad (NS-0), como factor B, dos dinamizaciones centesimales de NaM (NaM-7CH y NaM-31CH) y un control sin medicamento (NaM-0CH). Las variables respuesta evaluadas fueron longitud parte aérea (LPA), longitud parte radicular (LPR), grosor de tallo (GT), área foliar (AF), potencial hídrico (PH), contenido relativo de agua (CRA), clorofila ‘a’, clorofila ‘b’ y clorofila total. Con el tratamiento homeopático NaM-7CH, se registraron valores superiores en LPR y con NaM-31CH, mayores valores promedio en clorofila ‘a’, clorofila ‘b’ y clorofila total. Con el tratamiento salino NS-50 se obtuvieron valores mayores para LPA, LPR, GT, AF, CRA, clorofilas ‘a’, ‘b’ y totales. Los valores promedio mayores en la morfología de la planta correspondieron a las interacciones NS-50/NaM-7CH y NS-50/NaM-31CH. Esto sugiere un efecto positivo NaM sobre variables relevantes de respuesta productiva de S. bigelovii y su potencial aplicabilidad en el cultivo hidropónico de esta halófita costera.

Background: Goat milk production has been increasing in northern Mexico; however, there is little information available about its quality. Objective: To compare goat milk quality during three seasons among creole goats in a traditional grazing system and stabled Saanen and French-Alpine goats. Methods: An experiment was performed in a completely randomized nested design with seasonality factor (fixed effects) with three levels (rain, transition, and drought) and breed factor (fixed effect with three levels (Creole, Saanen and French-Alpine)) nested within the season-of-the-year factor. Fifteen goats were randomly selected: five Creole in the extensive grazing system, five stabled Saanen, and five stabled French-Alpine. The factors assessed in milk were fat content, non-fat solids, protein, lactose, salts, density, freezing point, conductivity, and pH (using a Lactoscan® device). Results: With respect to season for all the breeds: fat, non-fat solids, protein, lactose, and salt contents were higher (p≤0.05) for goats sampled in the rainy season, followed by drought and transition seasons, respectively. The variables related to milk quality by breed and season showed that milk fat content of creole goats was greater (p≤0.05) in the drought season; salt and non-fat content (p≤0.05) in the three seasons of the year; density and protein increased (p≤0.05) in the transition and rainy seasons, while lactose was greater (p≤0.05) in drought and rainy seasons; protein was greater (p≤0.05) in transition and rainy seasons; and the freezing point was lower (p≤0.05) in the transition season. Regarding conductivity, French-Alpine milk was greater (p≤0.05) in the drought season. Conclusion: Season of the year significantly affects milk quality, with increased quality during the rainy season in creole grazing goats.

El mildiu velloso (Peronospora belbahrii) afecta el desarrollo de la albahaca (Ocimum basilicum) y su control es complicado, debido al uso restringido de fungicidas. El objetivo de este estudio fue someter semillas de albahaca variedad Nufar a tratamientos de termoacondicionamiento de 40, 50 y 60°C expuestas a diferentes intervalos de tiempo (30, 60 y 90 min) para evaluar la relación existente entre la aparición de los síntomas de la enfermedad con la humedad relativa y temperaturaambiente, así como el efecto de los tratamientos de preacondicionamiento de la semilla en la severidad e incidencia de la enfermedad en la planta, y su respuesta fisiológica. Las semillas se sembraron en macetas bajo malla sombra ycuando las plantas alcanzaron 15 cm de crecimiento, se infectaron con P. belbahrii. La incidencia de la enfermedad se determinó semanalmente y 60 días después de la siembra se determinaron las variables morfométricas y fisiológicas mostrando diferencias significativas entre temperatura, tiempo de exposición e interacción en la mayoría de las variables evaluadas. Se observó una disminución en la incidencia de la enfermedad en plantas de semillas sometidas a condicionamiento térmico tratadas a 60°C por 60 min de exposición. Este mismo tratamiento mostró menor apertura estomática y transpiración y mayor concentración subestomatal deCO2, lo que sugiere una probable relación con la entrada de P. belbahrii a la hoja disminuyendo su incidencia.

Basil (Ocimum basilicum L.) is a medicinal and aromatic plant of commercial interest; it can be grown in salinized soils by applying a stress mitigator. The objective was to evaluate the biochemical response of two basil varieties inoculated with AMF Rhizophagus fasciculatus and appraise its usefulness as a NaCl-stress mitigator. A completely randomized design with a factorial arrangement, four replicates per treatment and four plants per replicate was used. Three factors were considered, (1) two basil varieties (Napoletano and Nufar); (2) three NaCl concentrations (0, 50 and 100 mM); and (3) R. fasciculatus inoculum absence or presence (0 and 10 g). The variables evaluated were a substrate chemical analysis; shoot (STP) and root (RTP) total protein content; shoot (SP) and root (RP) proline content; shoot (SGA) and root (RGA) glutathione peroxidase activity; spore count and colonization. The spore content was 50 to 70 spores per gram of inoculum. The STP and RTP were highest in both varieties in 0 mM with AMF and decreased in Napoletano in 100 mM. The SP and RP were highest in Nufar in 50 and 100 mM with AMF and lowest in Napoletano in 0 and 50 with AMF. The SGA and RGA were highest in Napoletano in 50 and 100 mM with AMF. The colonization was high; however, decreased as NaCl increased. These results suggest that inoculation with AMF has a positive effect to mitigate NaCl-stress and a biochemical benefit for basil plants.

Halophytes are capable of growing in saline environments. However, this attribute results from a wide genetic variability, making it difficult to approximate halophytes’ agroecological management. We examined the hydro-climatological attributes associated with the distribution of species of the genus Suaeda in NW Mexico and SW USA, and for S. edulis in central México. The analysis focused on the introduction of the semi-domesticated species Suaeda edulis as a new crop, from central regions of México, reaching an average yield of 8 Mg ha−1 of biomass, to arid NW México. The list of Suaeda species was elaborated from the eHALOPH and Calflora databases, and the NW México Herbarium Network. According to the Hydro-Environmental Availability Index (HEAI), the central regions of Mexico reflect a greater water availability, suitable for S. edulis. In such a humid region, HEAI varied from 6 to 18, indicating sufficient moisture for crops. In contrast, other Suaeda species, including S. nigra, S. esteroa, and S. californica, spread in NW Mexico and SW United States, where the water availability is null during the year, with HEAI scoring from 0 to 4. Under such dryness, S. edulis in NW Mexico will require water through optimized irrigation and plant breeding strategies to ensure its viability as a new crop.

El uso indiscriminado de fertilizantes ha contribuido a la salinidad del suelo tanto como al agotamiento de recursos minerales del mismo ocasionando así dependencia a los fertilizantes sintéticos por parte de los productores agrícolas. El objetivo del presente trabajo fue determinar el contenido inorgánico de N, P, K en las formas asimilables para las plantas de seis abonos orgánicos potenciales a utilizarse en la agricultura orgánica, bajos los principios del cuidado al medio ambiente. Las determinaciones de los elementos fueron realizados a través de un espectrofotómetro marca HANNA modelo HI83225-01. El abono con mayor contenido de nitrógeno es sus formas asimilables fue el guano de murciélago, seguido por la gallinaza y lombricomposta Fertium®. En el caso del fósforo, el abono que mostró la más alta cantidad fue de igual manera el guano de murciélago seguido por la gallinaza y estiércol de vaca. Para la determinación de potasio fue el guano de murciélago quien obtuvo el resultado más alto junto con la gallinaza y lombricomposta Fertium ®. Los seis abonos observaron valores altos de conductividad eléctrica (CE), y la gallinaza, guano de murciélago y estiércol de vaca observaron los mayores valores de éste parámetro, relacionados de forma signif icativa con el contenido de nutrientes. En cuanto al pH los seis abonos se encontraron con valores dentro de los permitidos por las normas mexicanas. Los resultados permiten generar información del contenido de nutrientes de los seis abonos para realizar su adecuada aplicación por los productores.

Separately and in combination a marine yeast Debaryomyces hansenii and a marine bacterium Stenotrophomonas rhizophila were evaluated for their biocontrol potential against Fusarium proliferatum on muskmelon fruit. The results show that the mixture of yeast and bacterium in vitro reduced the growth of F. proliferatum, possibly due to either by direct parasitism, nutrient competition, lytic enzymes, biosurfactants and/or volatile organic compounds (VOCs). Disease incidence and lesion diameter caused by F. proliferatum on muskmelon was reduced significantly, especially when fruit was inoculated with the mixture of D. hansenii + S. rhizophila. These results indicated that D. hansenii, S. rhizophila and their combination treatments were effective for the postharvest biocontrol of fruit rot on muskmelon.

Muskmelon (Cucumis melo L.) is a primary crop of Mexico. Nevertheless, the fruit has a high susceptibility to postharvest fungal diseases. Fusarium species are one of the main causes of diseases that limit production of muskmelon. The objective of this study was to characterize and identify by taxonomic keys and molecular markers species of Fusarium related to rot of muskmelon var. Reticulatus in Northwest Mexico. To identify the causative agent, fruits were collectedm from cultivated fields. The isolated fungi were inoculated on muskmelon to determine its pathogenicity. Morphological analyses as well as molecular techniques confirmed that the pathogen was the fungus Fusarium proliferatum.

Capsicum annuum var. aviculare is one of the most extremely hot chilies, measuring between 50,000 and 100,000 Scoville Units. In the present work we studied the growth and development of chiltepin (Mazocahui), under field conditions, inoculated with previously selected and cultivated native strains of Bacillus amyloliquefaciens and Azospirillum halopraeferens. The seed was inoculated by the vacuum technique, and later at 34, 120, 180 and 210 days after germination. A drip irrigation system with a salinity (TDS) = 0.8 ppt was used. The results show that germination is significantly favored by the promoter effect caused by the beneficial bacteria. These inoculants increased some parameters of growth and development. We found significant differences regarding the control for the total weight and length of root and stem of the plants, as well as the total content of proteins, and in some parts of the plant analyzed as stem and leaf. Both bacteria increased fruit yield in the Mazocahui genotype. Our findings suggest that the application of strains of Bacillus amyloliquefaciens and Azospirillum halopraeferens, influence the increase in yield of Capsicum annuum var. aviculare, under field conditions. In addition, the data show the usefulness of the inoculation of chiltepin seed for agricultural producers in semi-arid areas where salinity is a problem.

La albahaca (Ocimum basilicum L.) es una especie que presenta variabilidad en la tolerancia a distintos tipos de estrés abiótico y se considera una planta sensible a la salinidad en las etapas iniciales de su crecimiento. El objetivo del presente estudio fue determinar el efecto de la salinidad en la germinación de albahaca. Veinte variedades se sometieron a tres concentraciones de NaCl (0, 50 y 100 mM) en un diseño completamente al azar con cuatro repeticiones. El trabajo se desarrolló en cámara de germinación. Las variables que se midieron fueron tasa y porcentaje de germinación, longitud de radícula, altura de plántula, biomasa fresca y seca de radícula y parte aérea. Los resultados evidenciaron que las variedades Sweet Dani, Red Rubin, Genovese Italian, Mrs Burns, Cinnamon, Emily y Dolly tuvieron una mejor respuesta en las variables germinación, tasa de germinación, longitud de radícula, altura de plántula, biomasa fresca y seca de radícula y parte aérea. Se discute la respuesta diferencial entre las variedades al someterlas a diferentes niveles de NaCl.

Antecedentes y Objetivos: Los tés recreativos son bebidas preparadas, por infusión/ebullición, de diferentes partes de plantas que se consumen en un entorno social/alimenticio. Se consideran generalmente saludables y con usos medicinales, aunque ese no es su único propósito de consumo. En México, los tés recreativos prácticamente no se mencionan en los estudios etnobotánicos. Este estudio describe la etnobotánica, contenido de fenólicos y actividad antioxidante de plantas silvestres empleadas como tés recreativos en dos rancherías de las zonas montañosas de la región de Los Cabos, Baja California Sur, México: Reserva de la Biosfera Sierra La Laguna y comunidad San Blas-Cacachilas.Métodos: La información etnobotánica se obtuvo mediante encuestas semi-estructuradas y estancias con los rancheros de ambas comunidades. Se calculó el porcentaje de citas, preferencia y valor cultural de cada especie registrada, además de describir sus usos medicinales adicionales. El contenido de fenólicos y actividad antioxidante se determinó por métodos colorimétricos y fueron correlacionados con parámetros etnobotánicos.Resultados clave: Se registraron 12 taxa de plantas silvestres para elaborar tés recreativos, 11 en Sierra La Laguna y seis en San Blas-Las Cacachilas. La damiana (Turnera diffusa) obtuvo el mayor valor cultural (71.2%), seguido de margarita (Aloysia barbata) (41.1%) y anís silvestre (Tagetes filifolia/T. micrantha) (21.5%). Los tés recreativos tuvieron sus principales usos medicinales como antigripales/antitusivos y relajantes generales. El contenido de antioxidantes presentó correlación negativa con el porcentaje de citas y la preferencia. Los usos etnofarmacológicos de A. barbata y el helecho peyote (Pellaea ternifolia) son descritos por primera vez, y se documentaron nuevos usos para la damiana y el cerezo (Prunus serotina).Conclusiones: Los rancheros de Baja California Sur tienen gran afinidad por el consumo de tés recreativos de plantas silvestres, y aquellos usados para tratar padecimientos comunes como gripe/tos o estrés son los preferidos. El presente es el primer estudio etnobotánico específico para tés recreativos en México.

Halophytes are capable of growing in saline environments. However, this attribute results from a wide genetic variability, making it difficult to approximate halophytes’ agroecological management. We examined the hydro-climatological attributes associated with the distribution of species of the genus Suaeda in NW Mexico and SW USA, and for S. edulis in central México. The analysis focused on the introduction of the semi-domesticated species Suaeda edulis as a new crop, from central regions of México, reaching an average yield of 8 Mg ha−1 of biomass, to arid NW México. The list of Suaeda species was elaborated from the eHALOPH and Calflora databases, and the NW México Herbarium Network. According to the Hydro-Environmental Availability Index (HEAI), the central regions of Mexico reflect a greater water availability, suitable for S. edulis. In such a humid region, HEAI varied from 6 to 18, indicating sufficient moisture for crops. In contrast, other Suaeda species, including S. nigra, S. esteroa, and S. californica, spread in NW Mexico and SW United States, where the water availability is null during the year, with HEAI scoring from 0 to 4. Under such dryness, S. edulis in NW Mexico will require water through optimized irrigation and plant breeding strategies to ensure its viability as a new crop.

Ethnobotany is an adequate tool to identify the most import wild edible plants used by local people and to develop strategies for its sustainable use and policy making. This research records the wild edible plants used by the inhabitants of the Sierra la Laguna Biosphere Reserve, in Mexico, and identified priority species for sustainable development. The employed quantitative approach included the application of a food-oriented index named Food Significance Index (FSI), which integrated cultural, agricultural and food parameters; moreover, it used multivariate analysis to identify priority edible species for use and/or conservation. Fifty taxa were identified as the most important wild edible plants in the reserve, integrated into five priority groups. Foods in priority group 1 had the highest culinary diversity by grouping three fruits (Ficus petiolaris, Stenocereus thurberi, and Cyrtocarpa edulis), one almond-like seed (Cnidoscolus maculatus), one vegetable (Matelea cordifolia), and one condiment (Capsicum annuum). Priority groups 2-5 were selective for one or two types of food, such as fruits, teas, or seeds. Since group 1 was the most diverse, the FSI and the employed strategy permitted to identify the priority wild edible plant species with the highest potential for food security. The selected six species should be included in the future management program of the reserve as the priority wild edible plants to develop strategies for conservation, sustainable use, and improvement of the local population income. General policies to manage the selected six species are outlined.

Se define como reconversión de cultivos al cambio de producto o actividad que representa mayor rentabilidad económica y viabilidad social para el productor agrícola, al mismo tiempo que da un mejor uso del suelo, mejora la fertilidad del mismo y rompe con el ciclo biológico de plagas y enfermedades. En las zonas árido-desérticas, donde se produce el 70% de los alimentos agrícolas a nivel mundial, entre los factores adversos de tipo abiótico, se destaca el de la salinidad, el cual se agudiza conforme pasa el tiempo, mermando la producción de los cultivos convencionales. En este tipo de ambientes árido-salinos, las especies vegetales nativas son halotolerantes tolerando salinidades que varían de 2 a 55 g/L de agua. Algunas especies presentan tener una importancia agroindustrial como lo es la halófita Salicornia bigelovii, la cual puede ser utilizada para forraje, alimento humano, productos cosmetológicos, producción de biocombustibles, comprimidos a base de biomasa seca para la creación de escritorios, libreros, entre otros. La producción de Salicornia, demanda aguas salobres o agua de mar, la cual es un recurso que puede ser extraído de los litorales costeros o bien de tierras firmes continentales. El escalamiento de su producción depende de por tanto de la intensificación de nuestro conocimiento sobre diversos aspectos de su biología, fisiología, bioquímica e interacción con microorganismos benéficos que contribuyan a un mejor desarrollo y mejorada productividad de este recurso, sin alterar el medio ambiente

Los bioestimulantes del crecimiento vegetal son sustancias naturales para el tratamiento de los cultivos como activadores de las funciones fisiológicas, por lo que su aplicación permite un mejor aprovechamiento de los nutrientes y representan una opción adecuada para enfrentar problemas de estrés abiótico por salinidad. El objetivo del presente estudio fue determinar el efecto del humatos de vermicompost como atenuante de la salinidad en el crecimiento y desarrollo de plantas de dos variedades de albahaca (Ocimum basilicum L.), una tolerante y una sensible a la salinidad, las cuales se sometieron a tres concentraciones de NaCl (0, 50 y 100 mM) y a la aplicación de humatos de vermicompost con dos diluciones (0 y 1/60 v/v) en un diseño completamente al azar con seis repeticiones. El trabajo se desarrolló en una casa malla sombra y se midió longitud de tallo y raíz, biomasa fresca y seca de raíz, tallo, hoja y el área foliar. Los resultados mostraron que la variedad Napoletano en 0 mM de NaCl y la disolución de 1/60 (v/v) de humatos de vermicompost fue la de mejor respuesta en todas las variables medidas, mientras que los valores inferiores los presentó la variedad Sweet Genovese en 100 mM de NaCl. Se discute la respuesta diferencial entre las variedades al someterlas a diferentes niveles de NaCl y la aplicación de humatos de vermicompost.

The objective of this study was to compare the morphology of M. spicata and R. officinalis plants, and the relative abundance quantification, colony-forming units, ribotypes, and biofilm former bacteria under an inorganic fertilizer and the use of vermicompost leachate in the rhizosphere under a closed hydroponic system. In mint (Mentha spicata) plants treated with the vermicompost leachate, growth increase was determined mainly in root length from an average of 38 cm in plants under inorganic fertilizer to 74 cm under vermicompost leachate. In rosemary (Rosmarinus officinalis), no changes were determined between the two treatments. There were differences in the compositions of microbial communities: For R. officinalis, eight ribotypes were identified, seven for inorganic fertilizer and four for vermicompost leachate. For M. spicata, eight ribotypes were identified, three of them exclusive to vermicompost leachate. However, no changes were observed in microbial communities between the two treatments. Otherwise, some changes were observed in the compositions of these communities over time. In both cases, the main found phylum was Firmicutes, with 60% for R. officinalis and 80% for M. spicata represented by the Bacillus genus. In conclusion, the use of vermicompost leachate under the hydroponic system is a viable alternative to achieve an increase in the production of M. spicata, and for both plants (mint and rosemary), the quality of the product and the microbial communities that inhabited them remained unaltered.

Attenuators of salt-stress favor the use of effluents, being a low-cost organic product. The present study aimed to evaluate the effect of vermicompost leachate (VL) added to shrimp-culture effluent on seeds and seedlings of Salicornia bigelovii (Torr.) under salt-stress, evaluating germination, water relations variables, and biomass. Seeds were irrigated with distilled water (DW) (CE: 0.0027 dS m−1), freshwater (FW) (CE: 1.36 dS m−1), seawater (SW) (CE: 55.83 dS m−1), shrimp residual water (SRW) (CE: 59.85 dS m−1), and with the same water sources but adding VL in 1:20 v/v. The means for the index of germination rate (IGR), germination energy (GE), and germination time (MGT) were higher with DW, DWVL, FW, and FWVL, decreasing with the others (p ≤ 0.05). In seedlings, the lowest water potential (Ψw) and osmotic potential (Ψs) were observed with SW, SWVL, SRW, and SRWVL (p ≤ 0.05), evidencing higher stress but the highest relative water content (RWC). The fresh and dry biomass increased and showed significant differences with SRW, and adding VL (DWVL, FWVL, SWVL, and SRWVL) acted as an effective attenuator of salt-stress. The response of water relations variables suggested an osmotic adjustment for mitigating the salt-stress in seedlings, lowering the Ψw and Ψs but increasing the RWC.

Objetivo: realizar la valoración económica del consumo y producción de materias primas para la elaboración de biodiésel en Guatemala. Metodología: se utilizó fue el Método de Valoración Contingente para estimar el valor económico-ambiental que los consumidores y productores le otorgan a la producción de las materias primas Higuerillo (Ricinus communis) y Piñón (Jatropha curcas) para generación de biodisel. Para el caso de la Palma Africana (Elaeis guinnensis), se utilizó el método de valoración denominado Cambio de Productividad para establecer el excedente del productor y el método de valoración contingente para determinar el excedente de los consumidores. Resultados: los resultados del análisis de valoración económica ambiental reportan bienestar o excedentes para el consumo de biodiésel y la producción de las tres materias primas a valor presente en el orden de los US $71 millardos de dólares para un periodo de quince años y con la meta de sustituir el 80% del diésel por biodiésel con el cultivo y producción de 374,832 hectáreas. De este excedente total, el 99.76% está dado por el excedente de los consumidores por lo que el bienestar de los productores de las materias primas a valor actual se estimó en US $169 millones. Limitaciones: son las propias de la metodología de valoración económica que se utilizó, ya que al generar mercados hipotéticos se pueden caer en sesgos de la información los cuales se reducen por las técnicas estadísticas utilizadas. Conclusiones: se recomienda que la asignación de recursos se debe orientar a la demanda de los compradores que más valoran el consumo de biodiésel, es decir aquellos que muestran una mayor disposición a pagar (DAP).

La aplicación de sustancias húmicas, estimula mecanismos bioquímicos, fisiológicos, se han realizado investigaciones que revelan las propiedades y funciones de estas sustancias. El objetivo de esta investigación fue evaluar el efecto de diferentes concentraciones de Liplant® aplicadas vía foliar (1/10, 1/20, 1/30 v/v y un control-agua destilada-) en el crecimiento, producción y calidad de fruto de tomate, y factibilidad económica. Realizándose bajo condiciones de campo y utilizando un diseño de bloques completos al azar, 5 días después del trasplante se midió altura, diámetro de tallo; 65 días después, se consideró peso fresco y seco de frutos, diámetro polar y ecuatorial, número de frutos, rendimiento, acidez titulable, sólidos solubles totales, índice madurez, contenido de vitamina C, pH del jugo del fruto, pérdida de humedad y firmeza de frutos. La factibilidad económica se realizó considerando rendimiento, valor y costo de producción, beneficio neto, costo y la relación beneficio/costo. Se realizaron análisis de varianza y comparaciones múltiples de medias (Tukey HSD p= 0.05). El pH de jugo no mostró diferencias significativas entre concentraciones de Liplant®. Altura, diámetro del tallo, número de frutos, diámetro polar y ecuatorial, peso fresco y seco de frutos, rendimiento, firmeza de fruto, sólidos solubles totales, vitamina C y pérdida de humedad de fruto mostraron valores superiores cuando las plantas se asperjaron con la dilución de Liplant® de 1/30 (v/v). La dilución de 1/30 (v/v) de Liplant® generó un beneficio de $36 753.9 miles de pesos Cubanos por hectárea, un beneficio/costo de $3.60 pesos cubanos y un costo por peso de $0.21.

Aloe vera L. is a perennial liliaceous plant with succulent green leaves, it is a xerophyte with economic and social value, but little is known about its response to salt stress and its mechanisms of tolerance, especially at moderate concentrations. The objective was to investigate the effect of salinity stress (0, 30, 60, 90 and 120 mM NaCl) on Aloe by measuring physiological and morphometric traits related to growth. The results of measuring physiological traits showed no significant differences compared to the control at 30 and 60 mM (chlorophylls a, b, total, relative water content, net assimilation rate, specific leaf weight, and specific leaf area), even at 90 mM or 120 mM most parameter variations were not significantly different. Similarly, for morphological traits no significant differences were found compared to the control for all 16 morphological traits at 30 mM, or even at 60 mM since at this concentration only one trait varied significantly (1 out of 16). Although the general trend of increasing NaCl was to lower leaf fresh weight as salinity increased, presumably due to a decrease in water content. However leaf dry weight was not significantly reduced at any of the salinity concentrations applied. Thus, total dry leaf biomass was basically the same or similar, this suggesting that Aloe has an ability to withstand these levels of salinity stress. It is noteworthy to point out, that there is a general trend of lower growth (lower parameters both physiological and morphological) that is not significant at low doses (30 and 60 mM), however becoming more significant at higher doses (90 and 120 mM). Thus, we suggest that Aloe has continuum responses to NaCl stress.

Because the high biodiversity of Mexico about 12% of the country's total area is included as a Natural Protected Areas (NPAs); however, in the last years, according to the official data, an astonishing number of mining concessions covering 28% of the total area of the country has been granted already. The objective of this work is to quantify the geographical overlap of mining concessions with the federal NPAs of Mexico including the exploration/exploitation status of minerals to be extracted. We use geo-referenced polygons of the NPAs and those of mining exploration and exploitation concessions until 2010 and calculated their overlap extension with the application of ArcView GIS 3.3 (ESRI; Redland, CA, U.S.A.). Our results showed that a total of 1609 mining concessions covering an area of 1,486,433 ha geographically overlaps with the NPAs. With the exception of Natural Monuments (NM), all the different categories of NPAs in Mexico showed mining concessions; 75% of Natural Resources Protection Area (NRPA); 63% of Biosphere Reserve (BR); 47% of Protected Area for Flora and Fauna (PAFF); 22% of Sanctuary (S); and 15% of National Park (NP). The impacts of metal mining activities on NPAs are not only limited to biodiversity and affectation to human communities, but they also have a radius of influence not yet evaluated since most of the NPAs have a special role in supplying watersheds and aquifers. Obviously, currently in Mexico a NPA decree does not represent an obstacle to megamining projects; in consequence, their real environmental impacts are underestimated. It is a priority to legally support canceling the mining concessions already granted in the NPAs and stop granting new ones in the future. In the proportion to which environmental authorities continue to openly accept mining concessions within the NPAs, through modifying management programs that allow these activities, they may cause a significant increase in rejections of local people toward the changes in management programs and on the promotion of new NPAs in Mexico.

Salicornia bigelovii Torr. is a potential new crop for coastal and saline lands, because of the oil content of its seeds, its properties as fresh vegetable, forage, and other uses. As a true halophyte, it can grow with seawater irrigation. The aim of this study was to determine the phenology and water requirements of Salicornia as a new plant resource in growing areas for salt-tolerant crops in coastal and saline lands, and elucidate scenarios of sustainability about these issues. Water requirements were estimated in experimental plots on the coastal line and fulfilled with drip irrigation connected to seawater aquaculture discharge ponds, 30 m from the sea. The recorded phenological events were germination, flowering, fructification, maturation, and physiological death. Results reflect the difficulty to adopt it as a new crop because of its long-life cycle, around nine months, contrasting with the life cycle of common crops, from three to four months. Irrigation needs reached a depth of 240 cm, significantly exceeding those of conventional crops. Such limitations are highlighted, but also its potential use as a biofilter of coastal aquaculture effluents, being a productive target-biomass, feasible to be used as a dual-purpose use of water and energy required in aquaculture farms.

In Baja California Sur, Mexico, a foliar disease occurred on sweet basil which seriously affected its quality and yield. The most common symptoms were yellowing and necrosis on leaves, caused by a downy mycelium growth on the lower leaf surface. Symptomatic leaves from two sampling sites were collected for morphological studies and molecular analysis of pathogen DNA. Based on morphological characteristics (sporangiophore size of 240–530 × 7–11 μm, branches of 5–8 order and a sporangia size of 27–31 × 21–25 μm) and molecular analysis (the GenBank blast of the PCR assays showed unique rDNA sequence data with 99% similarity to P. belbahrii), the pathogen was identified as Peronospora belbahrii, the causal agent of basil downy mildew. This is the first report of P. belbahrii affecting sweet basil in Mexico.

An automated irrigation system was developed to optimize water use for agricultural crops. The system has a distributed wireless network of soil-moisture and temperature sensors placed in the root zone of the plants. In addition, a gateway unit handles sensor information, triggers actuators, and transmits data to a web application. An algorithm was developed with threshold values of temperature and soil moisture that was programmed into a microcontroller-based gateway to control water quantity. The system was powered by photovoltaic panels and had a duplex communication link based on a cellular-Internet interface that allowed for data inspection and irrigation scheduling to be programmed through a web page. The automated system was tested in a sage crop field for 136 days and water savings of up to 90% compared with traditional irrigation practices of the agricultural zone were achieved. Three replicas of the automated system have been used successfully in other places for 18 months. Because of its energy autonomy and low cost, the system has the potential to be useful in water limited geographically isolated areas.

The aim of this research was to investigate the effect of two different production systems, open-field and shade-enclosure, and four gypsum doses, to find the best environmental option in terms of physiological, morphometric characteristics and with optimum yield in two crops, oregano and thyme in Baja California Sur, Mexico. One cultivar of oregano and one of thyme were grown in shade-enclosure and open-field environments and evaluated for photosynthetic rate, transpiration rate, stomatal conductance, chlorophyll, leaf area, fresh and dry biomass and yield. The results showed significant differences between environmental conditions, crops and their interaction. Gypsum doses had no significant effect on any of the variables measured. For both species shade-enclosure variables measured were more favorable than open-field. In general, of the two crops, oregano performed better than thyme under shade-enclosure conditions, except for Chl a, b, total and leaf water potential which were higher in thyme.

Cowpea and kidney bean plants were grown in a hydroponic system, and the effect of calcium silicate supplied to the nutrient solution under salt stress was investigated. The plants were subjected to four different treatments: (1) nutrient solution alone (C), (2) nutrient solution + 40 mmol l )1 NaCl (NaCl), (3) nutrient solution + 40 mmol l )1 NaCl + 0.5 mmol l )1 CaSiO3 (NaCl + Si1) and (4) nutrient solution + 40 mmol l )1 NaCl+1 mmol l )1 CaSiO3 (NaCl + Si2). The results showed that, in both species, salinity reduced all growth variables but silicate supplementation however partly overcame this growth reduction. Addition of silicate in NaCl-stressed plants maintained membrane permeability. Net photosynthesis, chlorophyll content, stomatal conductance and transpiration were higher in plants under control treatment, and the inclusion of silicate in the nutrient solution resulted in a slight increase in these plant parameters. Intercellular CO2 was slightly higher in plants under silicate treatment than in plants under control or NaCl treatment. Calcium concentration in shoots and roots in both species was slightly higher in the treatments where silicate was added. Potassium concentration for salt treatment was reduced in shoot and root of both species in the absence of silicate. Sodium and chloride concentration in shoots and roots in both species were slightly higher in the presence of NaCl and were slightly reduced in the plants under silicate treatments. The results suggest that, in hydroponically grown plants, the inclusion of silicate in the nutrient solution is beneficial because it improves growth, physiological parameters and may contribute to a more balanced nutrition by enhancing nutrient uptake under NaCl-stressed conditions. Added calcium silicate may ameliorate the parameters affected by high salinity, may reduce sodium and chloride, and can

This study calculated the compositional nutrient diagnosis (CND) norms of cowpea (Vigna unguiculata (L.) Walp.), as well as identified significant nutrient interactions of this crop growing in an irrigated calcareous desert soil. Three genotypes were distributed in rows in a 2-ha field. The soil showed high heterogeneity in its chemical properties. For statistical analysis, 86 foliar composite samples from healthy plants were used. Preliminary CND norms were developed using a cumulative variance ratio function and the χ2 distribution function. Means and standard deviations of row-centered log ratios V X of five nutrients (N, P, K, Ca, and Mg) and a filling value R, which included all nutrients not chemically analyzed. Preliminary CND norms are: V N * =0.174±0.095, V P * =−2.172±0.234, V K * =−0.007±0.267, V Ca * =−0.022±0.146, V Mg * =−1.710±0.132, and V R 5 * =3.728±0.084. These CND norms are associated with dry bean yields higher than 1.88 t ha−1, and are associated with the following foliar concentrations: 26.2 g N kg−1, 2.5 g P kg−1, 22.9 g K kg−1, 21.6 g Ca kg−1, and 4 g Mg kg−1. Cowpea plants growing in desert calcareous soils took up lower amounts of N, P, and K than those considered as optimum in a previous report. Six interactions were strongly indicated for cowpea through principal component analyses: positive for Ca–Mg, and negative for N–Ca, N–Mg, Ca–P, Mg–P, and K–P. Furthermore, two interactions were identified using simple correlations, negative N–P and positive K–Ca.

Mineral-nutrient stress is one of the main factors limiting crop production, especially in arid lands. The mineral requirement of a crop is difficult to determine, and the interpretation of foliar chemistry composition is not easy. This study was conducted to compute the minimum yield target for fresh fruit of yellow pepper (Capsicum annuum L.) and the corresponding Compositional Nutrient Diagnosis (CND) as well as to identify significant nutrient interactions of this crop in desert calcareous soils. Preliminary CND norms were developed using a cumulative variance-ratio function and the chi-square distribution function. From a small database, we computed means and standard deviations of row-centered log ratios, VX, of five nutrients (N, P, K, Ca, and Mg) and a filling value, R, which comprises all nutrients not chemically analyzed and quantified them in 54 foliar samples of the popular yellow pepper cv. ‘Santa Fe’. This cultivar is widely grown in northwest Mexico under arid conditions. These norms are associated to fresh fruit yields higher than 15.04 t ha–1. Principal-component analyses, performed using estimated CND nutrient indexes, allowed us to identify four interactions: negative P-Ca, P-Mg, and N-K, and positive Ca-Mg. Pepper plants growing on calcareous soils tend to take up more Ca and Mg than considered as optimum in other soil conditions.

In Baja California Sur (bcs), Mexico, dry-semi warm and warm climates prevail associated to an extreme trend of diurnal temperatures and the environmental dryness. In this State, the maximum summer t exceeds 40° C and the minimum varies from 5 to 12° C, with a minimal for the State of 2° C in winter, at the top of the Sierra de La Laguna; only Los Cabos region has a warm humid climate. Because precipitation in the state is low, oscillating from 310 mm in the southern area of the state to 120 mm per year in the northern portion, predictions and scenarios under climate conditions point to an intensification of droughts. The aim of this work was to carry out a comparative analysis of trends of temperature, precipitation and hydro-environmental aridity among contrasting localities of bcs, by means of the application of Aridity Indexes and the determination of the Standardized Water Gap (bhe), through a numerical scale modification of the De Martonne Index. With the values of temperature and precipitation for the different climate change scenarios for four weather stations, the indicators Hydro Environmental Availability Index (idha) and Hydro Environmental Drought Index (isha) were calculated to determine their trend and the consequent bhe, an innovative quantification of water deficit, which is proposed in this paper. The maximum value of bhe (10 units), indicating prevalence of drought, is observed from February to June in almost the entire state. Results suggest that bhe tend to increase and intensify under climate change conditions, which is more evident from the South towards the North of the State. According to the trends of the indexes idha, isha and bhe, under six scenarios of climatic change for four regions of bcs, bhe can be estimated with a major significance for the region Gustavo Díaz Ordaz-Vizcaíno, Mulegé County, in the North of the State, where may reach a value bhemax = 10 and bhemin = 7.23, values which suggest extreme dryness, corresponding to the maximum values among localities. We conclude that the analysis of trends in PP and t and their integration into bi-parametric indicators are a reliable tool for the construction of scenarios and climate change trends.

Background Despite the ecological and socioeconomic importance of wild Capsicum annuum L., few investigations have been carried out to study basic characteristics. The peninsula of Baja California has a unique characteristic that it provides a high degree of isolation for the development of unique highly diverse endemic populations. The objective of this study was to evaluate for the first time the growth type, associated vegetation, morphometric traits in plants, in fruits and mineral content of roots, stems and leaves of three wild populations of Capsicum in Baja California, Mexico, near biosphere reserves. Results The results showed that the majority of plants of wild Capsicum annuum have a shrub growth type and were associated with communities consisting of 43 species of 20 families the most representative being Fabaceae, Cactaceae and Euphorbiaceae. Significant differences between populations were found in plant height, main stem diameter, beginning of canopy, leaf area, leaf average and maximum width, stems and roots dry weights. Coverage, leaf length and dry weight did not show differences. Potassium, sodium and zinc showed significant differences between populations in their roots, stems and leaves, while magnesium and manganese showed significant differences only in roots and stems, iron in stems and leaves, calcium in roots and leaves and phosphorus did not show differences. Average fruit weight, length, 100 fruits dry weight, 100 fruits pulp dry weight and pulp/seeds ratio showed significant differences between populations, while fruit number, average fruit fresh weight, peduncle length, fruit width, seeds per fruit and seed dry weight, did not show differences. Conclusions We concluded that this study of traits of wild Capsicum, provides useful information of morphometric variation between wild populations that will be of value for future decision processes involved in the management and preservation of germplasm and genetic resources.

En México 30% de su superficie agrícola está afectada por la salinidad. Lo anterior expuesto repercute para que una agricultura convencional a base de glicófitas, no sea redituable y productiva. Con el interés de ampliar el conocimiento con halófitas de interés agroindustrial y poder proponerlas al sector productivo que presenta problemas de sales, se desarrolló el presente estudio bajo condiciones de salinidad clorhídrica y sulfática inducida, evaluando dos genotipos de Salicornia bigelovii en las etapas de germinación y desarrollo (genotipo mejorado SOS-7 y genotipo silvestre Bahía de Kino= BK=), desarrollándola en condiciones de salinidad: dos de cloruro de sodio (NaCl) a 0.5 molar y a 1 molar y dos de sulfato de calcio (Ca2SO4+2H2O) a 0.5 Molar y a 1 Molar, con la inoculación de dos bacterias promotoras del crecimiento vegetal (BPCV) (Azospirillum halopraeferens= Ah y Klebsiella pneumoniae= Kp) y un control sin inocular. Los resultados indican que al evaluar a Salicornia en condiciones salinas clorhídricas y sulfáticas con la inoculación de BPCV, entre los resultados obtenidos figuran que un porcentaje mayor de germinación fue observado en presencia de las BPCV, sobresaliendo aquellos inoculados con Kp. Se observó, que conforme la salinidad incrementa, Kp presenta tener mayor efectividad con el genotipo silvestre BK. Estudios concernientes como posibles biofertilizantes son necesarios en las diferentes etapas fenológicas con los genotipos en estudio, quienes para la etapa de germinación, resultaron tener expectativas.

The effects of salinity on the growth and production of `nopalitos' (young cladode sprouts) of Opuntia ficus-indica (L.) Mill. cv. Copena V-1 were investigated. Salinity (NaCl) irrigation levels with electrical conductivities of 2, 5, 10, 13, 18 and 21 dS m–1 were used. In general, all cladode variables (stem area, number of young cladodes, length and width of cladodes, and fresh and dry weights) decreased with increasing salinity. The root-to-stem ratio and young cladode water content decreased significantly as salinity increased. Other variables that decreased with increasing salinity included harvest index, relative growth rate, stem area ratio, dry mass accumulation, and Na+ and Cl– concentrations. For rooted cladodes, increased salinity decreased fresh weight, succulence, and root fresh weight, dry weight and length. Our conclusions suggest that this species is salt sensitive; however, there is some indication that it could be effectively managed in saline environments. Further studies and evaluation of different cultivars are needed to identify the mechanism of adaptation of salt tolerance in this species. Einflusse von NaCl-Versalzung auf Wachstum und Produktion von jungen Kladodien beiOpuntia ficus-indica Der Einflus der Versalzung auf Wachstum und Produktion von jungen Kladodien `nopalitos' (cladode sprouts) von Opuntia ficus-indica (L.) Mill.-cultivar Copena V-1 wurden untersucht. Versalzte Bewasserungsmengen (NaCl) mit einer elektrischen Konduktivitat von 2, 5, 10, 13, 18 und 21 dS m–1 wurden verwendet. Grundsatzlich nahmen alle Kladodienvariablen (Stengelflache, Anzahl von jungen Kladodien, Lange und Breite der Kladodien, Frisch- und Trockengewicht) mit zunehmender Versalzung ab. Das Wurzelstengelverhaltnis und der Wassergehalt junger Kladodien nahm signifikant mit ansteigender Versalzung ab. Andere Variablen, die mit zunehmender Versalzung abnahmen, einschlieslich Ertragsindex, relative waren Wachstumsrate, Stengelflachenverhaltnis, Trockenmasseakkumulation und Na+ sowie Cl– Konzentrationen. Fur bewurzelte Kladodien fuhrte eine zunehmende Versalzung zu einer Abnahme des Frischgewichtes und der Sukkulenz sowie des Wurzelfrischgewichtes, des Trockengewichtes und der Lange. Es kann angenommen werden, dass diese Art salzempfindlich ist; allerdings gibt es keinen Hinweis, dass mit Erfolg in einer salzigen Umwelt behandelt werden kann. Weitere Untersuchungen und unterschiedliche Kultivare werden benotigt, um den Mechanismus der Adaption der Salztoleranz in dieser Art zu identifizieren.

La importancia economica de la albahaca ( Ocimum basilicum L.) a nivel mundial, ha impulsado la busqueda de estrategias como el acondicionamiento previo a la semilla para mejorar los indices de vigor en la planta, relacionados con un rendimiento mayor, calidad y tolerancia a algun tipo de estres . El objetivo del presente estudio fue determinar el umbral optimo de acondicionamiento de la semilla con diferentes gradientes de escarificacion sobre las caracteristicas de vigor relacionadas a variables morfometricas y fisiologicas en plantulas de albahaca durante las etapas de germinacion, emergencia y desarrollo vegetativo inicial. Semillas de albahaca variedad Nuffar se sometieron a tratamientos de acondicionamiento termico mediante la exposicion de calor seco, en cuatro gradientes de temperatura (40, 50, 60 y 70°C) y diferentes intervalos de tiempo (30, 60 y 90 min) y un tratamiento control (25°C), mediante un diseno completamente al azar con arreglo factorial con cuatro y/o cinco repeticiones. Los resultados mostraron que la temperatura y los tiempos de exposicion afectaron significativamente ( p ≤0.05) las variables de tasa y porcentaje de germinacion y emergencia, asi como las variables morfometricas y fisiologicas de la planta. En la etapa de germinacion, el tratamiento de 70oC afecto negativamente la respuesta de la planta en todas las variables evaluadas, independientemente de los tiempos de exposicion, mientras que los tratamientos de 40, 50 y 60oC fueron iguales al control. En la etapa de emergencia, se observo una tendencia determinada hacia el tratamiento de 60oC por un tiempo de exposicion de 60 min, el cual mejoro significativamente las caracteristicas de vigor. Sin embargo, no fue asi para el tratamiento de 70oC, el cual provoco disminucion en las variables evaluadas. Asimismo, durante la etapa vegetativa inicial, la exposicion a 60oC por 30 y 60 min mejoro significativamente las variables morfo fisiologicas de las plantas comparado con el control y el resto de los tratamientos.

La albahaca (Ocimum basilicum L.) presenta gran variabilidad en la tolerancia a distintos tipos de estres. Es considerada una planta sensible a la salinidad en las etapas iniciales de su crecimiento. Con este trabajo se pretendio evaluar la respuesta de variedades de O. basilicum a la influencia de diferentes niveles de NaCl. Dichas variedades poseen buen comportamiento agricola, pero se desconoce su tolerancia a la salinidad. La experiencia se llevo a cabo en condiciones controladas, donde las plantas se desarrollaron en una camara de crecimiento en presencia de tenores salinos. Se realizaron evaluaciones de altura de la planta, longitud de la raiz y la biomasa expresada como unidad de biomasa fresca y seca de la raiz y tallo, al inicio y al finalizar el ensayo. El analisis de las respuestas de las variedades indico que, estas, en condiciones nutricionales normales, presentaron un ritmo de crecimiento relativamente semejante y que la adicion de NaCl al medio provoco alteraciones en su crecimiento. Se observo que las Basil Genoveser Italiam, Basil Sweet Dani, Basil Red Rubin, Basil Thai, Basil Dolly, Basil Cinamon, Basil Mrs Burns, Basil Emily, Basil Sweet Genoveser, Basil Dolce Vita mostraron una mayor respuesta en los indicadores germinacion, tasa de germinacion, longitud de la radicula, altura de la planta, biomasa fresca y seca de la radicula, biomasa fresca y seca de la parte aerea y ademas los cultivares con menor respuesta en esta fase son cultivares Basil Lemon, Basil Siam Queen,Basil Dark Opal, Basil Spicy Glove, Basil Licorice, Basil Purple Ruffles, Basil Lettuce Leaf, Basil Italiam Large Leaf, Basil Genoveser, Basil Napoletano, las que se vieron afectadas negativamente por el NaCl, aunque el dano fue mas pronunciado en unas variedades que en otras. ABSTRACT Basil (Ocimum basilicum L.) presents great variability in tolerance to different types of stress. It is considered sensitive to salinity in the initial stages of plant growth. This work was intended to evaluate the response of varieties of O. basilicum to the influence of different levels of NaCl. The varieties have good agricultural performance, but its tolerance to salinity is unknown. The experiment was conducted under controlled conditions where the plants were grown in a growth chamber in the presence of saline tenors. Evaluations of plant height, root length and biomass expressed as a unit of fresh and dry biomass of the root and stem, at the beginning and end of the test were performed. The analysis of the responses of the varieties indicated that they, under normal nutritional conditions, showed a relatively similar rate of growth and that the addition of NaCl to the environment caused alterations in growth. It was observed that Basil Genoveser Italiam, Dani Sweet Basil, Basil Red Rubin Basil Thai Basil Dolly, Cinamon Basil, Basil Mrs Burns, Emily Basil, Sweet Basil Genoveser, Basil Dolce Vita showed a greater response in indicators germination rate, germination, radicle length, plant height, fresh and dry biomass of the radicle, fresh and dry biomass of the aerial part and also cultivars with reduced response at this stage are cultivars Basil Lemon, Basil Siam Queen, Dark Opal Basil Basil Spicy Glove, Basil Licorice, Basil Purple Ruffles Basil Lettuce Leaf, Basil Italiam Large Leaf Basil Genoveser, Basil Napoletano, which were negatively affected by NaCl, although the damage was more pronounced in some varieties than others.

Enrique Troyo-Dieguez1, Arturo Cruz-Falcon1, Alejandra Nieto-Garibay1, Ignacio Orona-Castillo2 , Bernardo Murillo-Amador1, Jose Luis Garcia-Hernandez2 and Alfredo Ortega-Rubio1 1Programa de Agricultura en Zonas Aridas, Centro de Investigaciones Biologicas del Noroeste, S.C. (CIBNOR, S.C.). La Paz, Baja California Sur; 2Facultad de Agricultura y Zootecnia (FAZ), Universidad Juarez del Estado de Durango, Gomez Palacio, Durango; Mexico

In this work we present and discuss some of the advances reached in relation to environmental crop management and adaptation to warming climates of legume crops, frequently associated to plant breeding, towards drought tolerance. At the same time, the benefits related to the contribution to the development of an appropriate legumes-based agriculture for arid zones are analyzed. The Leguminosae and Gramineae families are by far the world’s most important sources of food. Legumes include beans, soybeans, peas, alfalfa, and other crops, which supply protein fats, fiber and wood. Through their root nodules, inhabited by Rhizobium bacteria, the legumes also improve the nitrogen balance in the soil. Legumes comprise one of the largest plant families in the world, with near 18,000 species. Most species are tropical and include trees, woody vines, and herbaceous plants. All legume plants bear pods or legumes, which are diversely modified within the family. Most have compound leaves. As regards to warming climates under the effects of climate change, drought is defined as any period during which water deficits in the plant or agroecosystem affect growth and development; in this sense, the duration of drought determines the quantity of damage caused to crops. Two reasons are analyzed to develop programs of breeding and management directed to drought tolerance by means of an environmental understanding and ecophysiological selection of plants, according to their interactions with the environment: The first one is to maximize the productivity and consistently the plant performance, stabilizing or increasing productivity. The second one is to improve the drought tolerance; under this consideration the mechanisms of water conservation, constitute for the plants an important option to survive a drought, although they tend to limit their productive potential. It is concluded that an appropriate ecological management of crops and the ecophysiological selection can constitute a feasible way for agricultural sustainability.

El uso de bionutrientes estimula la emergencia y el crecimiento vegetal debido a que están compuestos por sustancias naturales activadores de las funciones fisiológicas de las plantas, por lo que su aplicación permite un aprovechamiento mejor de los nutrientes y representa una opción para enfrentar problemas de estrés abiótico por salinidad. El objetivo del presente estudio fue determinar el efecto de un bionutriente (FitoMas-E) derivado de la caña de azúcar como atenuante de la salinidad en la emergencia y el crecimiento de plántulas de variedades de albahaca (Ocimum basilicum L.) con respuesta diferencial al estrés por salinidad. Tres variedades de albahaca, Napoletano, Emily y Nufar se sometieron a cuatro concentraciones de NaCl (0, 50, 100 y 150 mM) y cuatro dosis de FitoMas-E (0, 0.5, 1.0 y 1.5 mL L-1) en un diseño completamente al azar con arreglo factorial con cuatro repeticiones. El trabajo se desarrolló en una estructura de malla sombra y las variables que se midieron fueron, porcentaje y tasa de emergencia, longitud de radícula, altura de plántula, biomasa fresca y seca de radícula y de parte aérea. Los resultados evidenciaron que en condiciones de estrés salino (NaCl) de moderado a severo, las variables disminuyeron significativamente, siendo largo de la raíz, altura de la planta y biomasa seca de raíz en 150 mM de NaCl las más afectadas. Se observó que cuando se aplicó FitoMas-E las plantas incrementaron significativamente sus valores en las variables estudiadas, lo que revela el efecto estimulante de este bionutriente, siendo 0.5 mL L-1 la dosis estimulante para la variedad Napoletano y 1.0 mL L-1 para la variedad Emily, aún y cuando se encontraban en condiciones de estrés salino hasta 100 mM de NaCl. Para la concentración de 150 mM se evidenció una afectación extrema para las variedades Emily y Nufar.

For a sustainable management of grazing lands, is necessary to know the strategy of nature to sustain the grassland,in consequence, the management schemes must be based in programs related to an environmental characterizationand adequate monitoring. With the aim to develop a tool to support the diagnosis of grasslands, we hereby proposethe application of the Hydro-Environmental Availability Index (HEAI), with scale from 0 to 10. According to theapplication of HEAI in 36 localities of Sonora, Mexico, five of them (13.9 %) fluctuated from 0 to 2.5, in consequence,their grasslands are highly vulnerable to drought, with very low possibilities for management. Twenty (55.6 %)oscillated from 2.5 to 5, suggesting a management with severe restrictions. Eleven (30.5 %) fluctuated from 5 to 7.5,proposing a sustainable management with adequate rotations and preventions during a drought, and none of localitiesreached values for HEAI > 7.5, high potential for sustainable management, with appropriate rotations. It must beconsidered that the actions to prevent the effects of overgrazing, not always are enough to mitigate the overwhelmingconsequences of droughts, which are exacerbated by climate change.

Diurnal and seasonal water relations and ecophysiological variables (soil humidity, transpiration, evapotranspiration, stomatal resistance, morphological changes, production), matched with some microclimatological variables, were studied in a hot pepper (Capsicum frutescens) experimental plot. Two treatments of plants with plastic mulches were assigned, black and blank-opaque, to compare them with plants without a mulch, established at the Experimental Station of CIBNOR in La Paz Baja California Sur, Mexico. Plants with blank-opaque plastic mulch showed the highest values of flower number, fruit production, leaf area, and canopy-projected area. Also, the biggest evapotranspiration rates were recorded from January to April for plants under the blank-opaque plastic mulch. Soil water content appeared to be a primary determinant factor for production. Soils under the blank-opaque plastic mulch had the biggest water content along the experiment. Plants without any plastic mulch had the lowest availability of soil water, rendered the lowest fruit production, and registered the highest evapotranspiration rates. May and June were the months with the highest air temperature during the experiment. Plants with black plastic mulch had intermediate records among the other two groups. When plants were allowed to face a drought stress, they responded through an osmotic adjustment for maintaining a low water potential, and thus supporting a partial turgor pressure. This adjustment was evident to be coupled with a stomatal regulation in order to minimize the loss of water through the transpiration process. Some drought tolerance strategies as a leaf size reduction were more evident in plants without a mulch.

Diurnal and seasonal water relations, soil humidity, transpiration, water demand, stomatal resistance, and fruit production, as well as some microclimatic parameters, were studied in a semidomesticated chile ecotype (Capsicum frutescens) under two treatments of plastic mulches, black and opaque, and compared with plants without a mulch in Baja California Sur, a Mexican semiarid state. Plants with opaque plastic mulch showed the highest chile production and total growth. The biggest transpiration rates from January to April was evidenced also by this treatment. The soil water content seemed to be determinant. Opaque plastic mulch plants had more soil moisture during the whole experiment. Plants without plastic mulch had the least chile production, with a lesser soil water content. These plants evidenced an osmotic adjustment under drought stress with low water potential, maintaining a partial turgor pressure, and stomatal regulation, in order to control the lost of water by transpiration.