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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.

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.

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.

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.

"Los bioestimulantes vegetales activan el proceso de germinación de las semillas; accionan funciones f isiológicas en las plantas, contienen sustancias propias del metabolismo vegetal, que mejoran el uso de nutrientes y son una opción para mitigar estrés por salinidad. El objetivo del estudio fue evaluar el efecto de un bioestimulante de origen natural (FitoMas-E ® ), como atenuante de la salinidad en la germinación de las variedades de albahaca ( Ocimum basilicum L.) Emily, Napoletano y Nufar. Las semillas se sometieron a concentraciones de NaCl (0, 50, 100 y 150 mM) y dosis de FitoMas-E ® (0, 0.5, 1 y 1.5 mL L -1 ), en un diseño completamente al azar con arreglo factorial con cuatro repeticiones, en condiciones controladas. Se evaluó porcentaje y tasa de germinación, altura de la plántula, longitud de radícula, biomasa fresca y seca de la radícula, biomasa fresca y seca de la parte aérea. Los resultados mostraron que la altura de la planta, longitud de la radícula, biomasa fresca de parte aérea y biomasa seca de la radícula con 150 mM de NaCl fueron las más dañadas. Napoletano y Nufar mostraron longitud de radícula mayor en 0 mM y conforme la concentración de NaCl incrementó, la longitud de radícula disminuyó signif icativamente para las tres variedades. Las plántulas de semillas tratadas con FitoMas-E ® , incrementaron longitud de radícula, destacando Napoletano en 1 mL L -1 y Nufar con 0.5 mL L 1 . Napoletano mostró biomasa fresca de parte aérea mayor en 0 mM con 0.5 mL L -1 de FitoMas-E ® . Las plántulas de Napoletano de semillas tratadas con 0.5 mL L -1 de FitoMas-E ® incrementaron la biomasa seca de radícula en 0 y 50 mM de NaCl. Se concluye que el FitoMas-E ® con dosis de 0.5 y 1 mL L -1 mitiga el efecto del estrés salino de moderado a severo en semillas de albahaca."

En la naturaleza las plantas se encuentran expuestas a diversas condiciones de estrés que retardan su desarrollo y disminuyen su rendimiento. Uno de los problemas agrícolas más extendidos es la acumulación de sales en la superficie del suelo o la salinización del agua para riego. El objetivo del estudio fue evaluar un consorcio de hongos micorrízicos arbusculares (HMA) de las especies Funeliformis mosseae y Claroideoglomus etunicatum como posibles mitigadores del estrés por NaCl en plántulas de variedades de albahaca en la etapa de emergencia. Se utilizó un diseño completamente al azar con arreglo factorial. El factor 1 fueron tres variedades de albahaca (Nuffar, Genovese y Napoletano), el factor 2 fueron tres niveles de estrés salino (0, 50 y 100 mM de NaCl) y el factor 3, los hongos micorrizicos arbusculares (0 –control- y 1 g del inoculo) con cuatro repeticiones de 30 semillas cada una. Se evaluó la composición química del sustrato y del inóculo utilizados, la tasa y porcentaje de emergencia, altura de plántula, longitud de raíz, biomasa fresca de parte aérea y de raíz y porcentaje de colonización. Los resultados mostraron que tanto el sustrato como el inóculo utilizados fueron adecuados para el desarrollo de las especies de HMA evaluadas y para la especie vegetal en estudio. Ninguna de las raíces de las plántulas de las variedades en estudio mostraron presencia de vesículas, arbúsculos y/o hifas cenocíticas. Todas las variables presentaron valores superiores en aquellas plántulas cuyas semillas se inocularon con HMA. Las variedades mostraron diferencias para la mayoría de las variables evaluadas, siendo Napoletano superior, mientras que Genovese mostró lo contrario. La mayoría de las variables disminuyeron sus valores conforme las concentraciones de NaCl incrementaron.

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

Any improvement in agricultural systems that results in higher production should also reduce negative environmental impacts and enhance sustainability. The aim of this research was to investigate the effect of two different production systems, one open-field and the other shade-enclosure with four bocashi doses, in order to find the best environmental option in terms of yield, physiological and morphometric characteristics in one oregano (Origanum vulgare L.) cultivar. In this study a completely randomized block design was used with four replications and evaluated for photosynthetic and transpiration rate, stomatal conductance, chlorophyll, leaf area and temperature, aerial and roots fresh and dry biomass, fresh and dry yield. The results showed that oregano adapted best to the shade-enclosure with increase yield of fresh and dry leaf weight of 165% and 118%, respectively, when compared to open-field. Also, higher doses of bocashi improved yield in both environments but more so in shade-enclosure. Soil moisture retention was higher in shade-enclosure which was reflected in physiological variables for soil matric potential, transpiration, stomatal conductivity, photosynthesis being significantly higher in shade-enclosure compared to open-field, thus improving yield. It seems that oregano plants can be grown and perform better under shade-enclosure than open-field and bocashi is a suitable organic fertilizer.

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.

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.

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 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.

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.

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.