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The improvement of the symbiosis generated by arbuscular mycorrhizal fungi (AMF) against pathogenic microorganisms has been described, however, the ef fect of AMF in peanut crops is of interest due to the value of the productive chain that has not been fully attended. Therefore, this research work evaluated six treatments: (T1) Control plants without AMF, (T2) Plants with vermicompost leachate, (T3) Plants inoculated with commercial mycorrhizae, (T4) Plants inoculated with native mycorrhizae, (T5) Plants inoculated with commercial mycorrhizae + leachate and (T6) Plants inoculated with commercial mycorrhizae + native mycorrhizae; in this sense, mycorrhizal fungi were isolated, identifying Rhizoglomus clarum, Acaulospora alpina and Acaulospora af f. bireticulata, and inoculated in peanut plants in an area of 144 m2 in the open, so that, to corroborate the incidence of the treatments evaluated, agronomic variables such as height, width of biomass, foliar damage by Cercospora personata, number of f lowers, were evaluated during the pre-harvest every 15 days and the post-harvest variables were; leaf area index, root length, fruit and lipid yield, as well as the prof ile of fatty acids present in the fruit. Finally, peanut quality was evaluated according to CODEX STAN 200-1995, showing that the best treatment was leaching + commercial mycorrhizae, reporting yields of 65.05% of fruits and 58% of total lipids, mostly monounsaturated fatty acids (52 % oleic acid) followed by polyunsaturated (21% linoleic acid), f inally according to CODEX STAN 200-199 the peanuts obtained correspond to the basic quality with dimensions of 4 to 4.5 cm wide and long respectively, these peanuts cannot be exported but they can be marketed in the country for agro-industrial transformation, allowing improved agricultural practices by reducing the use of agrochemicals.

A modified method for the direct extraction of DNA from alkaline-saline soils with minimum DNA fragmentation and a possible reduction in chimera formation during polymerase chain reaction (PCR) was developed. The commercial extraction kit Power Soil DNA (Mo Bio™ Laboratories, Inc.) was used as a reference technique. The method reported here was based on cell lysis employing ethylenediaminetetraacetic acid (EDTA), sodium dodecyl sulfate (SDS), and cell disruption with mechanical force with FastPrep-24™ equip followed by one cycle of freezing at -40 °C for 60 min and thawing at 65 °C for 20 min. The extraction method was tested for allophonic soils with large concentrations of organic matter, fulvic and humic acids, electrolytic conductivity (EC) ranging between 2.6 dS m-1 and 39.9 dS m-1, and pH between 8.8 and 10.9. The yield of DNA extracted depended on soil type, i.e., DNA extracted from soil varied between 2.35 (Texcoco-2) to 3.66 (Texcoco-1) μg DNA g-1 soil. The proposed method in this study produced enough DNA with yield and quality for PCR amplification of 16S rDNA when bovine serum albumin (BSA) was added to the reaction buffer. The DNA obtained had sufficient quality and yield for later use for 16S sequencing or possible use in other sequencing technologies, e.g. whole metagenome shotgun sequencing.

Hydrocarbon contamination cause serious environmental damage and human health problems, therefore, to resolve this problem has been proposed diversely remediation techniques friendly with the environment i.e. bioaugmentation, biostimulation, natural attenuation and phytoremediation. Among options, the phytoremediation causes minimum alterations to soil, low cost, it has proved good eff iciency and gained public acceptation. In the present study, the capacity of Mimosa pigra to restore a contaminated soil with both anthracene and phenanthrene was evaluated, along with the soil physicochemical changes due to both plant and contaminant presence in the soil. A silt-loam contaminated soil with 100 mg kg-1 (dry weight) anthracene and 200 mg kg-1 (dry weight) phenanthrene was used in all three treatments: Contaminated soil with M. pigra (C1), contaminated soil without M. pigra (C2), and not contaminated soil with M. pigra (C0) as control. After 70 days of experimentation both biomass and height of M. pigra was not affected due to soil contaminants. There was no difference among treatments for some physicochemical characteristics e.g. soil pH, electrolytic conductivity, soil-texture, and total nitrogen content throughout the experiment. M. pigra increased the soil water holding capacity after 50 and 70 days of the experiment, however, total organic carbon content was lower after 70 days compared to the control treatment. The higher contaminant removal rate was before 7 days of experimentation for all treatments. Anthracene and phenanthrene content were lower in treatments with the presence of M. pigra: 92% of phenanthrene and 80% of anthracene were removed in C1 while nearly 77% of phenanthrene and 60% of anthracene were removed in C2. This suggest a greater removal of contaminants using M. pigra. Total removal of contaminants was not achieved. However, M. pigra was able to accumulate both compounds, showing the M. pigra capability for bioremediation use in contaminated soils.

El chile xcat´ik (Capsicum annuum L.) es el segundo más consumido en la península de Yucatán, después del habanero. Los biofertilizantes microbianos son una opción factible de integrarse a los sistemas de producción para disminuir el uso de fertilizantes químicos. El objetivo del trabajo se basó en la evaluación del efecto de la aplicación de Bacillus subtilis, Trichoderma harzanium y un consorcio microbiano en las características agronómicas de la planta y la calidad del fruto del chile xcat´ik. El experimento se realizó en condiciones de invernadero, a través de un diseño experimental de bloques completos al azar con cuatro repeticiones. De acuerdo a los resultados se encontró que la aplicación de B. subtilis incrementó significativamente la altura de plantas respecto al testigo, así mismo la aplicación de B. subtilis y T. harzanium incrementó el volumen de raíz. Se observó que existen diferencias estadísticas en los contenidos de lípidos y proteínas en el fruto de plantas biofertilizadas con T. harzanium, y que en los frutos de plantas tratadas particularmente con B. subtilis y T. harzanium se acumulan mayores cantidades de fósforo.

The carrot is considered a model system in plant cell culture. Spray drying represents a widely used technology to preserve microorganisms, such as bacteria and yeasts. In germplasm conservation, the most used methods are freeze drying and cryopreservation. Therefore, the aim of this work was to evaluate the effect of spray drying on the viability and totipotency of somatic carrot cells. Leaf, root and stem explants were evaluated to induce callus with 2 mg/L of 2,4-dichlorophenoxyacetic acid (2,4-D). Calli obtained from the stem were cultivated in a liquid medium with 1 mg/L of 2,4-D. Cell suspensions were spray dried with maltodextrin-gum Arabic and maltodextrin-xanthan gum mixtures, two outlet air temperatures (50 and 60 °C) and 120 °C inlet air temperature. Results showed that carrot cells were viable after spray drying, and this viability remained for six months at 8 °C. The totipotency of the microencapsulated cells was proven. Cells that were not spray dried regenerated 24.6 plantlets, while the spray dried cells regenerated 19 plantlets for each gram of rehydrated powder. Thus, spray drying allowed researchers to obtain viable and totipotent cells. This work is the first manuscript that reported the spray drying of plant somatic cells.

This work was conducted with the objective to evaluate the effect of vermicompost application on chemical characteristics, energetic parameters and amino acids prof ile of hybrid race corn grain cultivated under open-f ield and rained conditions. The experiment was accomplished under a randomized complete design with three repetitions. Three treatments were evaluated: 1) Maize after inoculation with a commercial mycorrhizal arbuscular fungi mixture (Tec Myc 60®) plus vermicompost (V+M); vermicompost (V) and chemical fertilization (CF). Starch content in grain was 1.9% higher in V+M treatment in comparison with chemical, whereas crude protein, ether extract, crude f iber, acid detergent f iber, neutral detergent f iber, total phosphorous and phytic phosphorous were not different between treatments. Energetic parameters were not different between three treatments. 17 amino acids were evaluated of wich only tryptophan, leucine, valine, histidine and aspartic acid were higher in CF and V treatments in comparison with V+M treatment. In conclusion, it is possible to cultivate maize using vermicompost as fertilizer because chemical characteristics, energetic parameters and amino acids prof ile in maize grain were not affected compared with the maize cultivated with vermicompost added with biofertilizers (V+M) or with corn cultivated with chemical fertilizers (CF).

Tempisque (Sideroxylon capiri Pittier) is classified as a threatened species and has been reported with a high content of phenols and flavonoids in the leaves. The use of abiotic elicitors such as radiation has been reported due to the changes it produces in the metabolism of plants by activating their defense mechanisms and increasing the biosynthesis of bioactive compounds with antioxidant capacity such as phenols and flavonoids. Therefore, the aim of this work was to evaluate the effect of UV-B radiation on growth parameters and the synthesis of bioactive compounds in in vitro culture of tempisque callus. For the callus induction, we used thidiazuron (TDZ) and 2,4-dichlorophenoxyacetic acid (2,4-D) at 0, 0.5 and 1 mg/L. Calluses were exposed to UV-B radiation (0, 1, 2, 3 and 4 h/day) for two and four weeks. The highest callus formation index was obtained with TDZ and 2,4-D at 1 mg/mL. The greatest increase in the concentration of phenols and flavonoids was detected in the fourth week with 4 h of exposure per day. The highest concentrations of quercetin (230 µg/g dry weight), kaempferol (235 µg/g dry weight) and gallic acid (240 µg/g dry weight) were found in callus obtained from leaves explants.

The aim of this investigation was to determine the effect of vermicompost (V) and phosphate rock (PR) on blackberry (Rubus fruticosus L. agg.) plants inoculated with Glomus mosseae (Nicol. & Gerd.)...

Potato (Solanum tuberosum L.) is the fourth major crop worldwide after cereals. Some producers use irrigation water with high salinity, which consequently decreases the agronomic yield and potato q...

The aim of this investigation was to determine the effect of vermicompost, vermiwash, and phosphate rock on plant, total phenols, flavonoids, and anti-oxidant activity in Piper auritum Kunth leaves. P. auritum plants were obtained from cuttings and were planted according to the Box-Behnken experimental design with three repetitions at the central point. The factors and levels were vermicompost (10, 20, and 30 g plant−1), vermiwash (5, 10, and 15 mL plant−1), and phosphate rock (1, 2, and 3 g plant−1). Plant growth parameters (plant height, stem diameter, leaves number) and chlorophyll content were measured 1 month after treatment applications. Total phenols, total flavonoids, and 1,1-diphenyl-2-picryl-hydrazyl radical scavenging activity was measured after 4 months. Vermicompost, vermiwash, and phosphate rock had no statistically significant effect on plant growth. Plant height, stem diameter, leaves number, chlorophyll, innermost number, fresh weight stem, fresh weight leaves, fresh weight root, ...

Los protocolos actuales para la micropropagacion de Agave americana L. tienen limitaciones para su aplicacion comercial debido al bajo numero de plantas producidas por cada explante. La organogenesis indirecta podria ser una alternativa, sin embargo, es necesario optimizar los reguladores de crecimiento vegetal para maximizar el numero de plantas. El objetivo del trabajo fue optimizar la concentracion de acido 2,4-diclorofenoxiacetico (2,4-D) y de 6-bencil adenina (BA) sobre la induccion de callos embriogenicos en A. americana usando meristemos apicales como explante para maximizar el numero de brotes por callo, utilizando un diseno experimental de superficie de respuesta. Se utilizo el medio Murashige Skoog (MS) adicionado con 30 g l-1 de sacarosa, y con 0,11;0,18; 0,45 o 2,26 μM de 2,4-D, y 11,0; 22,0; 38,2 o 44,0 μM de BA. Se implementaron 9 tratamientos con 3 repeticiones y el numero de brotes por callo fue evaluado despues de 4, 16, 20 y 36 semanas. Se indujo el enraizamiento in vitro usando medio MS adicionado con acido indolbutirico (AIB). Se obtuvo un maximo de 74 plantulas por callo, usando 2,26 μM de 2,4-D y 38,2 μM de BA. En conclusion, la organogenesis indirecta podria ser una alternativa para la micropropagacion de A. americana L con fines comerciales.

The objective of this study was to investigate the effect of vermicompost, rock phosphate, Glomus fasciculatum (arbuscular mycorrhizal fungi), and Penicillium sp. (phosphate solubilizing fungi) on growth; mycorrhization percent; fructan, sucrose, glucose, and fructose contents in leaves and stem of Agave americana L. Experiments were done according to an orthogonal experimental design L8 with four variables at two levels: vermicompost (0 or 10 g per plant), rock phosphate (0 or 1 g per plant), G. fasciculatum (0 or 1 × 106 spores per plant), and Penicillium sp. (0 or 1 × 109 spores per plant). Vermicompost affected stem dry weight; the fructan, glucose, and fructose in stem; and mycorrhization percent in roots. Rock phosphate and Penicillium sp. increased the mycorrhization percent. Co-inoculation of Penicillium sp. and G. fasciculatum increased A. americana plant growth. The results obtained suggested a synergistic interaction between the arbuscular mycorrhizic fungi and the phosphate solubilizin...

The aim of this investigation was to determine the effect of vermicompost and phosphate rock on plant growth, total phenols, flavonoids, flavanones, and antioxidant activity in Annona purpurea Moc & Sesse ex Dunal leaves. Annona purpurea seedlings were planted according to factorial 32 experimental design with nine repetitions. The factors were vermicompost (0, 50, and 100 g plant−1) and phosphate rock (0 and 10 g plant−1). Plant height, stem diameter, number of leaves, and chorophyll content were determined one month after application of the different treatments and total phenols, flavonols, flavanones, total flavonoids, and 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity in dry leaves after 4 months. Plant height and stem diameter increased by phosphate rock, but not by vermicompost. Total phenols in leaves decreased by vermicompost. Flavonol content decreased by rock phosphate, whereas flavanones increased by vermicompost. Antioxidant activity decreased by vermicompost addition.

In the present study, the hexane, acetone and methanol extracts of stem, branches and roots from Crotalaria longirostrata were evaluated for their antifungal activity against Fusarium sp., Fusarium verticillioides and Aspergillus flavus. The variables analyzed were inhibition halos, mycelial growth inhibition, sporulation and minimum inhibitory concentration. Phytochemical analysis revealed the presence of saponins, coumarins, anthrones, anthraquinones, flavonoids and alkaloids on different organic extracts. The hexane extract showed zones of inhibition between 6.3 and 10.5 mm. The mycelia growth and sporulation of A. flavus were reduced to 90% with methanol extract. The minimum inhibitory concentration values obtained with hexane extracts were 6.75 mg mL-1 and with methanol extracts were 50 and 25 mg mL-1 for Fusarium strains. This is the first study reporting of phytochemical composition and biological activity of C. longirostrata that could be used as a natural alternative to control in vitro of certain important pathogenic fungi.

Worm-bed leachate is a nutrient-rich by-product of composting organic wastes with earthworms. Worm-bed leachate was stored and characterized while its possible antifungal activity towards the pathogenic fungus Colletotrichum gloeosporioides (Penz.) Penz. and Sacc. was investigated in vitro. The pH decreased from 9.6 at the onset of the storage to 8.9 after 28 days, while the total N and C nearly halved. The surfactin concentration in the worm-bed leachate reached 10.8 μg L−1 at day 10, while that of iturin A and iturin A homologues increased towards the end of the storage. Sterilized worm-bed leachate had little effect on the growth of C. gloeosporioides, but unsterilized worm-bed leachate inhibited growth 100%. It was found that unsterilized worm-bed leachate inhibited growth of C. gloeosporioides, but sterilizing the worm-bed leachate strongly reduced the inhibitory effect indicating that the microorganisms in the worm-bed leachate out-competed the fungus for nutrients or were antagonistic towa...

La leguminosa tropical Acaciella angustissima inoculada con o sin la cepa Sinorhizobium mexicanum ITTG R7T fue cultivada en un suelo tratado con (Al) para estudiar la tolerancia a este metal. Las plantas de A. angustissima fueron crecidas en el suelo con 0, 2, 4 y 6 mg de Al kg-1. Se hizo un seguimiento del efecto de Al e inoculacion en el crecimiento, la nodulacion, el contenido de nitrogeno y el contenido de taninos en las plantas. La altura, el peso seco total y el peso seco de la raiz de las plantas decremento significativamente cuando el suelo fue tratado con Al, pero incremento cuando fue inoculado. El Al disminuyo el numero de nodulos. El inoculo incremento el N total y el contenido de taninos de las plantas. En este experimento fue encontrado que el Al reduce el crecimiento de la leguminosa arbustiva tropical fijadora de N2 A. angustissima, mientras la inoculacion con S. mexicanum ITTG R7T estimula el crecimiento e incrementa el contenido de taninos y nitrogeno.

Jatropha curcas L. will be cultivated in large parts of the central highlands of Chiapas (Mexico) so that its seeds can be extracted for biofuel. Little is known how the cultivation of J. curcas, which contains phorbolesters, might affect soil processes. Soil was sampled at five locations and amended with leaves of J. curcas while dynamics of ammonium (NH4+), nitrite (NO2−) and nitrate (NO3−) and emissions of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), well known greenhouse gasses, were monitored. If we considered no priming effect, then between 12 and 31% of the C added with Jatropha leaves mineralized within 56 days. However, the concentration of mineral N (sum of NH4+, NO2− and NO3−) did not increase in the Jatropha-amended soils compared to the unamended soils. The mean CO2 emission rate increased significantly 3.7 times when Jatropha leaves were added to the different soils. The N2O emission was low in the unamended soil and remained

© 2015 The Netherlands Entomological Society. Social bee colonies can allocate their foraging resources over a large spatial scale, but how they allocate foraging on a small scale near the colony is unclear and can have implications for understanding colony decision-making and the pollination services provided. Using a mass-foraging stingless bee, Scaptotrigona pectoralis (Dalla Torre) (Hymenoptera: Apidae: Meliponini), we show that colonies will forage near their nests and allocate their foraging labor on a very fine spatial scale at an array of food sources placed close to the colony. We counted the foragers that a colony allocated to each of nine feeders containing 1.0, 1.5, or 2.0 M sucrose solution [31, 43, and 55% sucrose (wt/wt), respectively] at distances of 10, 15, and 20 m from the nest. A significantly greater number of foragers (2.6-5.3 fold greater) visited feeders placed 10 vs. 20 m away from the colony. Foraging allocation also corresponded to food quality. At the 10-m feeders, 4.9-fold more foragers visited 2.0 M as compared to 1.0 M sucrose feeders. Colony forager allocation thus responded to both differences in food distance and quality even when the travel cost was negligible compared to normal colony foraging distances (10 m vs. an estimated 800-1 710 m). For a nearby floral patch, this could result in unequal floral visitation and pollination.

The concentration of nitrous oxide (N 2 O) and carbon dioxide (CO 2 ) in the atmosphere has increased considerably over the last century, but few studies are available showing their production from soils in semi-arid areas. Soils from the tropical semi-arid Central Depression of Chiapas were sampled from fields cultivated with maize (MAI treatment), under canopy of Acacia angustissima (TIMBRE) or outside the canopy of the trees (OUT), adjusted to 40%, 60%, 80% or 100% of water-holding capacity (WHC) and amended with 0, 15 or 50 mg (NH 4 NO 3 )-N kg −1 dry soil. The production of N 2 O, CO 2 and concentrations of NH 4 + , and NO 3 − were monitored in the laboratory under aerobic conditions. Production of N 2 O in the first 3 days was significantly larger from the MAI and OUT soils, compared to the TIMBRE soil, while the addition of 50 mg inorganic N doubled the production of N 2 O. In all treatments, soil at 100% WHC had the largest production of N 2 O. The emission of CO 2 was significantly larger from soils at 60% and 80% WHC compared to the soil at 40% and 100% WHC, although the addition of inorganic N had no significant effect on CO 2 emission. The application of inorganic N and the absence of vegetation increased the production of N 2 O.

The effects of different inorganic fertilizers and rhizobial inoculation on shoot height, total shoot and root dry weight, nodule number, total shoot nitrogen, nitrogenase activity and tannic acid content of Acaciella angustissima (Mill.) Britton & Rose were investigated in the laboratory. Seedlings were grown in a climate chamber in glass tubes containing sterilized mixture of vermiculite and peat moss, and treated with combinations of nitrogen (N) at 45 mg plant¹, phosphorus (P) at 30 mg plant¹, potassium (K) at 20 mg plant¹ and inoculated with the bacterium Sinorhizobium mexicanum. The combined applications of N, P or K to uninoculated plants increased shoot height and dry weight as compared to the unamended plantlets. The tannin content in uninoculated plants was highest when amended with P+K. Treatment had a significant effect on plant growth, nodulation and tannin content varied. The plants treated with P + K + S. mexicanum had significantly longer shoot height, total shoot and root dry weight, nodule number, total shoot nitrogen, nitrogenase activity and tannic acid content in comparison with unamended plants. It was found that N reduced number of nodules, tannin content and nitrogenase activity of A. angustisisma. As such, farmers should refrain from applying N fertilizer, but could apply P and K to maximize tannin production in A. angustissima. Se investigaron en el laboratorio los efectos de diferentes fertilizantes inorgánicos y la inoculación rizobial sobre la altura de planta, peso seco total de planta, peso seco de raíz, el número de nodulos, el nitrógeno total de la planta, la actividad de la nitrogenasa y el contenido de ácido tánico de Acaciella angustissima (Mili.) Britton & Rose. Las plántulas fueron crecidas en una cámara climática en tubos de vidrio conteniendo una mezcla de vermiculita y turba, y tratadas con las combinaciones de nitrógeno (N) en 45 mg planta"¹, fósforo (P) en 30 mg planta"¹, potasio (K) en 20 mg planta"¹ e inoculado con la bacteria Sinorhizobium mexicanum. La combinación de las aplicaciones de N, P o K en plantas sin inocular incrementa la altura y el peso seco de planta en comparación con las plantas sin tratamiento. El contenido de taninos en plantas no inoculadas fue el más alto cuando suplementamos con P+K. El tratamiento tuvo un efecto significativo sobre el crecimiento de planta, modulación y el contenido de tanino variado. Las plantas tratadas con P + K + S. mexicanum tuvieron significativamente mayor altura de planta, peso seco total de planta, peso seco de raíz, el número de nodulos, nitrógeno total de planta, actividad de la nitrogenasa y contenido de taninos en comparación con las plantas sin suplementar. Fue encontrado que el N reduce el número de nodulos, el contenido de taninos y la actividad de la nitrogenasa de A. angustisisma. Como tal, los agricultores deberían abstenerse de aplicar el fertilizante de N, pero podrían aplicar P y K para maximizar la producción de tanino en A. angustissima.

El objetivo del trabajo fue evaluar el efecto de dos hongos micorrizicos arbusculares (HMA) a diferentes concentraciones de fosforo sobre la sobrevivencia y el crecimiento de plantulas de pina {Ananas comosus (L.) Merr.) obtenidas por micropropagacion. Las plantulas se multiplicaron masivamente en cultivos in vitro y se aclimataron gradualmente bajo un esquema de estres por temperatura en tres etapas secuenciales. Los efectos de los HMA y el fosforo no fueron significativos sobre la sobrevivencia y la altura de las plantulas, sin embargo, Glomus claroideum estimulo que las plantulas tuvieran mayor numero de hojas y peso seco. Los resultados sugieren que la altura de las plantulas fue mayor cuando fueron cultivadas con G. claroideum y 0,9 mM de fosforo.