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The use of phytonanoparticles in agriculture could decrease the use of fertilizers and therefore decrease soil contamination, due to their size being better assimilated in plants. It is important to mention that the nanofertilizer is slow-releasing and improves plant physiological properties and various nutritional parameters. The influence of soil and foliar applications of phytonanoparticles of ZnO with the Moringa oleifera extract under three concentrations (25, 50, and 100 ppm) was evaluated on the cherry tomato crop (Solanum lycopersicum L.). Synthesis of the phytonanoparticles was analyzed with ultraviolet-visible spectroscopy (UV-Vis) and infrared transmission spectroscopy with Fourier transform (FT-IR), as well as the analysis with the dynamic light scattering (DLS) technique. The morphometric parameters were evaluated before and after the application of the nanoparticles. The minerals’ content of fruits was done 95 days after planting. Results showed that soil application was better at a concentration of 25 ppm of phytonanoparticles since it allowed the greatest number of flowers and fruits on the plant; however, it was demonstrated that when performing a foliar application, the fruit showed the highest concentrations for the elements Mg, Ca, and Na at concentrations of 511, 4589, and 223 mg kg−1, respectively.

Las enfermedades causadas por Fusarium en Agave aumentan, lo cual significa importantes pérdidas económicas. Es necesario entonces buscar alternativas en la prevención y control de pató­genos para reducir el uso de fungicidas químicos, y así promo­ver un tipo de control de enfermedades que sea amigable con el ambiente. Los aceites y extractos de hojas de algunas plantas son eficientes en el control de plagas y enfermedades. Piper auritum (“hierba santa”) contiene aceites esenciales que cumplen funcio­nes ecológicas, como las de atraer polinizadores y causar efectos alelopáticos. Baccharis glutinosa (“jarilla”) también se usa en el tratamiento de diversas enfermedades infecciosas. Hay diferentes extractos de plantas que tienen una actividad biológica contra microorganismos que afectan cultivos importantes. El objetivo de esta investigación fue evaluar la actividad antimicrobiana del aceite esencial y extractos de dos plantas con uso tradicional en el estado de Chiapas sobre los hongos fitopatógenos (Fusarium spp.) de Agave spp. Los extractos de P. auritum y B. glutinosa se probaron contra los hongos fitopatógenos, como parte de un di­seño experimental completamente aleatorizado. Un ANOVA se realizó con seis tratamientos y tres repeticiones por tratamiento, utilizados en tres especies de Fusarium. El aceite esencial extraí­do de las hojas de Piper auritum tuvo el mayor efecto inhibi­dor significativo (96 h) sobre Fusarium oxysporum f. sp. comiteca (75.32%), Fusarium oxysporum f. sp. tequilana (86.57%) y Fu­sarium solani f. sp. comiteca (63.36%). Por lo tanto, P. auritum mostró un claro efecto fungistático.

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.

Yam bean (Pachyrhizus erosus (L.) Urb.) tuber has a low carbohydrate content and contains several aminoacids, but contains few active compounds, such as vitamins and antioxidants. Anthocyanins are antioxidants found in Rubus fructicosus L. The osmotic drying is a technique that can be used to impregnate antioxidants in a matrix, so the objective of this study was to impregnate yam bean tuber slices with anthocyanin. The effect of temperature (40, 50 and 60oC), sucrose content (40, 50 and 60oBrix) and vacuum pulse (0, 300 and 600 mbar) on water loss (WL), solid gain (SG), color changes (ΔΕ) and anthocyanin concentration (ΔA) during osmotic drying of yam bean slices was determined. Polynomial equations were used to determine changes in WL, SG, ΔΕ and ΔA of yam bean slices after 6 h of osmotic drying. An osmotic solution at 60oC with a SC of 40oBrix, applying a vacuum pulse of 12 mbar maximized anthocyanin impregnation (6.67 mg anthocyanin per g initial dry matter) in tuber slices. The Page equation predicted optimum WL, SG and ΔA of yam bean tuber slices during osmotic drying. No relation was found between temperature, sucrose content and vacuum pulse with K and n parameters in the Page equation.

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.

The objective of this work was to determine the effect of spray drying on the microbial survival of lactic acid bacteria (LAB), acetic acid bacteria (AAB) and yeast (Y), as well as on the volatile compounds retention of the “taberna”. Different mixtures of maltodextrin, gum arabic, xanthan gum and sodium alginate as coating materials, different proportions coating material:"taberna" (1:1, 1:2 and 1:3 v/v), as well as the effect of the feeding flow (3, 6 and 9 mL/min) and the inlet air temperature (80, 90 and 100 °C) in the dryer were evaluated on the efficiency of microencapsulation, microbial survival, water activity and the morphology of the microcapsules. Optimal conditions for the encapsulation of "taberna" to maximize microbial survival and microencapsulation efficacy were: feed flow of 3 mL/min, inlet air temperature of 97 °C and a mixture of MD-AG using a coating material:“taberna” ratio of 1:1 (v/v). With these conditions, in addition to maintaining the viability of the three microbial groups, most of the aromatic compounds of the "taberna" were retained.

Soy milk is a food rich in proteins, phenolic compounds and lactose-free. However, due to organoleptic and anti-nutritional characteristics, soy milk is not very popular among the population. The objective of this article is to evaluate the changes in the activity of α-galactosidase and β-glucosidase, as well as phytates, isoflavones, phenolic compounds contents and antioxidant activity of soy milk during the fermentation with Lactobacillus plantarum BAL-03-ITTG and Lactobacillus fermentum BAL-21-ITTG. Soy milk was fermented for 24 h with L. plantarum and L. fermentum separately, with an increase of 1.2 to 1.4 log CFU g-1 for both strains. The results showed that the strains are able to produce β-glucosidase, carrying out the conversion of β-glucosides in their corresponding aglycones, with an increase of 420 to 490 %. In addition, the strains can decrease approximately 20 % of the content of phytate in soy milk during fermentation. Therefore, both strains could be used in future works to obtain food from fermented soy milk.

Agave grijalvensis (B. Ullrich) was inoculated with Glomus fasciculatum (Thaxter sensu Gerd.) Gerd. and Trappe) and fertilized with different amounts of phosphorus (P) during plant development. Mycorrhizal colonization, fructan accumulation and fructosyltransferases enzymatic activities were determined. Glomus fasciculatum increased fresh weight of A. grijalvensis, the number of leaves, root length and fructan concentrations in stems and leaves. Phosphorus increased sucrose content, but reduced glucose and fructose concentrations in both leaves and stems. Activities of 1-fructosyltransferase (1-SST) (EC 2.4.1.99) and β-fructan-1-fructosyltransferase (1-FFT) (EC 2.4.1.100) were determined and explained due to different levels of fructans detected in A. grijalvensis plantlets.

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.)...

Pesticide by-products found in soil are usually more toxic and persistent than the pesticides themselves. For example, Endosulfan lactone (EL) (a by-product of the organochloride pesticide endosulfan). EL is created by the enzymatic activity (and related oxidative processes) of microorganisms in the soil. A sustainable method of EL removal is the introduction of Eisenia fetida earthworm. In this paper, it will be demonstrated the impact of vermicomposting process related to Eisenia fetida earthworm on EL by measuring initial and final concentrations of the compound and overall enzymatic activity in sterile and non-sterile solid substrate over 56 days. As a baseline, it be observed there were higher EL removals in non-sterile solid substrate (90.86%) at day 5 than in sterile solid substrate (83.86%) at day 14. In samples with Eisenia fetida, the presence of EL in non-sterile solid substrate was 36%, however in sterile solid substrate it was only 18% at day 1 and 7, with a maximum enzyme activity of 0.4659 mmol/mg protein per min at day 7. The evidence found in this study suggests that EL removal in a non-sterile solid substrate is higher when a vermicomposting is present and that the influence of microorganisms from the solid substrate with the earthworm, increases removal.

La quitinasa y B-1,3-glucanasa desempeñan una función importante en la reacción de defensa contra patógenos fúngicos. En Agave americana existe poca información sobre el comportamiento de estas proteínas en respuesta a la infección de Fusarium oxysporum. En este estudio, se realizó un análisis de microscopía electrónica de barrido (MEB) en raíces de A. americana infectadas con F. oxysporum y se evaluó la actividad de quitinasa y B-1,3-glucanasa en raíces de A. americana a 0, 7, 15 y 30 días después de inoculación con F. oxysporum. MEB reveló que 15 días después de la inoculación (DDI) son suficientes para que el hongo infecte las raíces de A. americana. La actividad de quitinasa en plantas infectadas incrementó significativamente a los 15 DDI con respecto a las plantas no infectadas, mientras que la actividad de B-1,3 glucanasa no presentó diferencia estadística significativa con plantas testigo. Los resultados sugieren que, en respuesta a la infección por F. oxysporum, A. americana activa proteínas PRs de tipo quitinasas.

Basil (Ocimum basilicum L.) is a hyperaccumulative herbaceous plant that has the ability to grow in contaminated soils and is believed to harbor a wide variety of bacterial species resistant to recalcitrant toxic chemical compounds. The objective of this work was to evaluate the potential for removal of decaclorobiphenyl PCB-209 by bacteria associated with the O. basilicum plant. A total of 34 endophytes and 52 strains from the rhizosphere of this plant were isolated using selective culture media. The adaptive capacity of the bacteria in phenol and Arochlor 1242 was initially determined and then a set of bacteria was selected and their removal potential of decachlorobiphenyl PCB-209 was evaluated. The phylogenetic analysis of 16S rRNA gene grouped to the O. basilicum isolates within bacterial genera Acinetobacter, Bacillus, Lysinibacillus, Novosphingobium, Pseudomonas, Rhizobium, Sphingobium, Stenotrophomonas, and Terribacillus as well as bacterial strains Pseudomonas taiwanensis BS-1, Rhizobium nepotum BS-2, Terribacillus sacharophilus BS-3, Stenotrophomonas rhizophila BS-4, Bacillus arybhattai BS-5, and Lysinibacillus macroides BS-6 showed the ability to adapt and use phenol and Arochlor 1242 as source of C. The strains BS-4 isolated from the root of the plant showed a higher potential from the removal of the PCB-209 (390.75 mg L−1) at an initial concentration of 500 mg L−1 and also had the ability to synthesize biosurfactant (EI = 60%) compared to the other strains evaluated. The diversity of bacteria associated to O. basilicum had biological qualities that may contribute to their adaptation and proliferation in an environment contaminated by PCB and be used efficiently as bioremediation to relieve agricultural soils contaminated by persistent organic compounds.

The aim of this work was to develop and evaluate the effect of an edible coating produced with protein isolate and gum from the Cajanus cajan seed to be applied to strawberries (Fragaria spp.). The films were formulated using 1 and 2% gum, and 5 and 10% protein isolate, as well as glycerol (2%) as a plasticizer. The formulated films were evaluated in terms of water vapor permeability (WVP), opacity, color, scanning electron microscopy, and texture. Once the ideal formulation with sufficiently low WVP and opacity was selected, it was applied to the strawberries, which were evaluated in terms of mass loss, color, firmness, acidity, pH, soluble solids, anthocyanin content, vitamin C content, and acceptability degree by an untrained consumer panel. Results showed that film made from 5% of protein isolate and 1% of gum had the lowest WVP of all treatments. Applied to strawberries, the coating resulted in a reduction of the total soluble solid content, the consumption of citric acid, and the mass loss of coated with respect to uncoated strawberries after 10 days of storage at 5 °C, without causing sensorial changes.

The aim of the present work is to evaluate the changes on the phenylalanine ammonia lyase (PAL) activity, phenolic compounds accumulation and photochemical efficiency in leaves of P. glandulosa treated with Cd2+ (0.001 M) and Cu2+ (0.52 M) concentrations for 96 h under hydroponic conditions. The results showed that only leaves treated with copper had a decrease in photochemical efficiency and leaf epidermal polyphenols in P. glandulosa leaves after 96 h of exposure. On the other hand the reverse-phase HPLC analysis revealed higher levels of phenolic compound (gallic, vanillic and caffeic acids) and flavonoids (rutin and kaempferol-3-O-glucosides) in plant leaves from Cu and Cd-treatments with respect to control plants. Finally, highest increments in PAL activity was observed in extracts of leaves treated with Cu and Cd (about 205 and 284%), respectively, with respect to control plants after 96 h treatment. These suggest that activation of phenylpropanoid pathway represent a source of nonenzymatic antioxidants that protect at P. glandulosa against oxidative stress when exposed to cadmium and copper. Hence future studies are necessary to elucidate the participation of phenylpropanoid pathway in the reduction of metal toxicity in Prosopis species.

Olive trees are one of the most important oil crops in the world due to the sensorial and nutritional characteristics of olive oil, such as lipid composition and antioxidant content, and the medicinal properties of its leaves. In this paper, callus formation was induced using nodal segments of olive tree (Olea europaea cv. cornicabra) as explants. Fatty acid profile, total phenolic compounds and total flavonoid compounds were determined in callus culture after 15 weeks and compared with leaf and nodal segments tissues. There was no statistical difference in phenolic compounds among leaf, nodal segments and callus culture, whereas flavonoid compounds were higher in leaf. Fatty acid profile was similar in leaf, nodal segments and callus culture and was constituted by hexadecanoic acid, octadecanoic acid, cis-9-octadecenoic acid, cis-9,12-octadecadienoic acid, cis-9,12,15-octadecatrienoic acid. Hexadecanoic acid was the main fatty acid in callus, leaf and nodal segments with 35.0, 39.0 and 40.0% (w/w), of the lipid composition, respectively. With this paper, it is being reported for the first time the capacity of callus culture to accumulate fatty acids. Our results could serve to continue studying the production of fatty acids in callus cultivation as a biotechnological tool to improve different olive cultivars.

The effect of metals on the photosynthetic activities and epidermal polyphenol content of Prosopis glandulosa and Prosopis juliflora leaves was investigated by the tissue tolerance test. Foliar tissues of Prosopis glandulosa and Prosopis juliflora were incubated with Cd2+ (0.001 M) or Cu2+ (0.52 M) concentrations for 96 h. The results showed that significant reductions (p < 0.05) of photochemical efficiency in P. juliflora leaves were found after 96 h of exposure to 0.52 M Cu2+ compared with Cd-treatments and controls. In contrast, P. glandulosa leaves showed a progressive increase on photochemical efficiency at 72 h after Cu-treatment. The results also showed a significant decrease (p < 0.05) of epidermal polyphenols in P. juliflora leaves after 24 h of exposure to 0.52 M Cu2+ compared with Cd-treatments and control leaves. On the other hand, the values of leaf epidermal polyphenols observed in P. glandulosa exposed to copper and cadmium did not show any difference with respect to control. These findings are very important and suggest that these compounds could be considered as a protection mechanism of P. glandulosa when is treated with these heavy metals. Finally, the results of bioaccumulation showed that the copper concentration in P. glandulosa was higher than the values detected in P. juliflora Nevertheless, the cadmium concentration in foliar tissues of P. juliflora was significantly higher than P. glandulosa after 96 h of exposure to Cu2+ or Cd2+. Therefore, future studies are necessary to elucidate the effects of heavy metals on the biosynthesis of flavonoids and participation of these compounds in the reduction of metal toxicity in Prosopis species.

Factors such as slow growth, low rates of sexual and asexual reproduction, and viability of seeds among others limit the massive propagation of Agave americana L. by conventional methods. In this study, callus induction and shoot proliferation was determined in A. americana using Murashige and Skoog (MS) medium supplemented with dicholorophenoxyacetic acid (2,4-D) and 6-benzyl adenine (BA). Meristematic tissue was used as the explants, and were placed on MS medium supplemented with 30.0 g·L−1 sucrose with 0.11, 0.18, or 0.45 μm 2,4-D and 11.0, 22.0, 38.2, 44.0, 58.7, or 73.3 μm BA. Treatments were implemented according to factorial experimental design 3 × 6. After 1 month, the number of explants with callus was determined, whereas the numbers of shoots per explant were monitored after 4, 16, 20, and 36 weeks. The maximum percent of explants with callus was obtained with 0.11 μm 2,4-D and 58.7 and 73.3 μm BA, whereas the maximum numbers of shoots per explant (71) were obtained with 0.11 μm 2,4-D and 73.3 μm BA. The effect of different concentrations of indolebutyric acid (IBA) in the rooting of shoots was evaluated. There were no significant effects of IBA on the number of roots, root length, and axillary roots. Plantlets were acclimatized in the glasshouse and they did not show any phenotypic alteration. This is a highly efficient protocol for the in vitro propagation of A. americana via indirect organogenesis.

In the present study the characterization and properties of silver nanoparticles from Prosopis glandulosa leaf extract (AgNPs) were investigated using UV–Vis spectroscopic techniques, energy dispersive X-ray spectrometers (EDS), zeta potential and dynamic light scattering. The UV–Vis spectroscopic analysis showed the absorbance peaked at 487 nm, which indicated the synthesis of silver nanoparticles. The experimental results showed silver nanoparticles had Z-average diameter of 421 nm with higher stability (−200 mV). The EDS analysis also exhibited presentation of silver element. Additionally, the different concentrations of AgNPs (25, 50, 75 and 100 mg/mL) showed antibacterial activity against Acinetobacter calcoaceticus and Bacillus cereus. Finally, AgNPs from leaf extracts of P. glandulosa may be used as an agent of biocontrol of microorganism of importance medical. However, further studies will be needed to fully understand the antimicrobial activity of silver nanoparticles obtain from P. gland...

The green iguana appears to be a reservoir for bacteria causing gastrointestinal infections in humans. The presence of diarrheogenicE. coli(DEC) pathotypes, however, has not been studied in this reptile. The aim of the current work was to investigate the prevalence of DEC in the intestines of 240 captive green iguanas, their phylogenetic groups, and the antibiotic susceptibility profile.E. colistrains were isolated from 41.7% of the intestinal content of green iguanas. DEC strains was identified in 25.9% of the screened population and were detected in the majority (62%, p=0.009] of those reptiles carryingE. colistrains. Among DEC strains, STEC strains carrying thestx1gene were the most prevalent pathotype isolated (38.7%), followed by EAEC and ETEC (27.4% each). Genetic markers of DEC strains belonging to the EHEC pathotype were not detected. More than a half of DEC strains were classified into the Clade I-II phylogroup (64.5%), followed by the phylogroup A (14.5%). The antibiotic susceptibility method demonstrated that a high proportion of DEC strains were resistance, or non-susceptible, to carbenicillin, amikacin, and ampicillin (85, 74, and 66%, respectively). We conclude that the green iguana kept in captivity is a reservoir of DEC strains bearing resistance to first-line antibiotics, including penicillins. Given the increase presence of the green iguana in Latin American households, these reptiles represent a potential source of transmission to susceptible humans and therefore a potential source of gastrointestinal disease.ImportanceLatin-American countries present a high burden of diarrheal disease. In this part of the world, besides common pathogens, diarrheal diseases are also caused by pathogenic types ofE. colireferred as “diarrheagenicE. coli” (DEC). While inhabitants of Latin American countries suffer of self-limiting diarrhea when infected with DEC, a main target of these strains are tourists from developed countries who are not exposed to DEC strains. Efforts are in place to decrease the burden of DEC-associated diarrheal disease. As such, this study investigated a potential reservoir of DEC strains that had been underestimated, the green iguana. These reptiles are very common in Latin American households and are found virtually everywhere in Mexico, Central and South America. We found that 25% of green iguanas carried DEC strains in their intestines. We also demonstrated a high prevalence of antibiotic resistance in these strains, posing a potential risk to humans.

Cotton production in the Mexicali valley is adversely affected by wilt and root rot disease associated with Fusarium species. Therefore, the aim of this study was to identify the antifungal activity and presence of lipopeptides genes in Bacillus subtilis strain Bs-Cach isolated from the rhizosphere of the cachanilla (Pluchea sericea). The dual culture technique was conducted to test antifungal effect of the Bs-Cach on the growth of Fusarium solani strains (ICA-3 and ICA-4, respectively), and the presence of iturin (ItuA), surfactin (SrfC), and fengycin (FenD) (lipopeptides genes), was evaluated by PCR analysis. The results obtained revealed that Bs-Cach inhibited the growth of F. solani ICA-3 and ICA-4, with a range of percentage inhibition from 50 and 52 after 120 h, respectively. On the other hand, our result of the PCR amplification of the lipopeptide genes from DNA of Bs-Cach showed solely the presence of iturin but not surfactin and fengycin genes. The analysis of sequence ituA present in Bs-Cach showed 84 % identity with iturin A synthetase of different B. subtilis strains. This study showed that B. subtilis Bs-Cach strain has the ability of inhibiting F. solani strains by at least one mechanism, the lipopeptide synthesis. This result turns Bs-Cach into a potential alternative for the biological control of F. solani. Nevertheless, this study was conducted under in vitro conditions, and further studies are required to investigate whether these results hold true under field conditions.

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, ...

The effect of plant growth-promoting bacteria inoculation on plant growth and the sugar content in Agave americana was assessed. The bacterial strains ACO-34A, ACO-40, and ACO-140, isolated from the A. americana rhizosphere, were selected for this study to evaluate their phenotypic and genotypic characteristics. The three bacterial strains were evaluated via plant inoculation assays, and Azospirillum brasilense Cd served as a control strain. Phylogenetic analysis based on the 16S rRNA gene showed that strains ACO-34A, ACO-40 and ACO-140 were Rhizobium daejeonense, Acinetobacter calcoaceticus and Pseudomonas mosselii, respectively. All of the strains were able to synthesize indole-3-acetic acid (IAA), solubilize phosphate, and had nitrogenase activity. Inoculation using the plant growth-promoting bacteria strains had a significant effect (p < 0.05) on plant growth and the sugar content of A. americana, showing that these native plant growth-promoting bacteria are a practical, simple, and efficient alternative to promote the growth of agave plants with proper biological characteristics for agroindustrial and biotechnological use and to increase the sugar content in this agave species.

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...

A diazotrophic bacterial strain denominated 11B isolated from the rhizosphere of a banana plant (Musa spp.) was characterized morphologically, biochemically, and phylogenetically, whereas the symbiotic potential of the strain was assessed through tests of host range, interstrain nodulation competitiveness, and capacity to synthesize indole-3-acetic acid (IAA) and solubilize phosphate. Based on morphological and physiological–biochemical properties, as well as 16S ribosomal deoxyribonucleic acid (rDNA) sequence and phylogenetic analysis, the strain 11B belonged to the genus Rhizobium with 100.0% sequence similarity with Rhizobium tropici CAF440. The optimum growth temperature and pH for strain 11B are 28°C and 7.2, respectively. This strain was able to produce IAA, solubilize phosphate, and fix large amounts of nitrogen (N2) and form effective nodules on the legumes Acaciella angustissima, Gliricidia sepium, Leucaena leucocephala, Lysiloma acapulcensis, and Phaseolus vulgaris. The rhizobial strain ...

The objective of this study was to evaluate the changes of green metallic nanoparticles on biochemical and physiological effects in Annona muricata L., plants. Changes in proline, phenolic compounds, antioxidants enzyme, phenylalanine ammonia lyase (PAL) activity and phytohormones in A. muricata leaves exposed to Ag, Cu and Cu/Ag phytonanoparticles were evaluated up to 120 h. The results showed that the foliar application of green metallic nanoparticles at 250, 500, 750 and 1000 ppm caused changes significantly in flavonoids, anthocyanins, phenylalanine ammonia lyase and peroxidase activities in A. muricata leaves after 120 h exposure. The foliar application of green nanoparticles stimulates the enhancement of the antioxidant protection system that protect at A. muricata against oxidative stress caused by reactive oxygen species (ROS). Our results showed that values of gibberelins, auxins and proline depended of nanoparticle concentration and composition.

The present study was conducted to evaluate the impact of monometallic and bimetallic nanoparticles (NPs) of copper (Cu) and silver (Ag) from Justicia spicigera on the photochemical efficiency and phenol pattern of Prosopis glandulosa. In this study, the existence of localized surface plasmon resonance absorption associated with the nano-sized nature of Ag, Cu and Cu/Ag particles was confirmed by the presence of a single peak around 487, 585, and 487/580 nm respectively. Zeta potential and electrophoretic mobility were found to be 0.2 mV and 0.02 μmcm/(Vs) for synthesized NPs indicating less stability and thus tendency to agglomerate, and broad distribution of particles. Cu-NPs and Cu/Ag-NPs demonstrate that the dispersed phase is stable and has a minimum particle size at zeta potentials above –30 mV. Changes in phenolic compounds, total chlorophyll, and photochemical efficiency in leaves exposed to Ag, Cu and Cu/Ag phyto-nanoparticles were evaluated up to 72 hours. The results revealed that Ag-NP and Cu-NP from J. spicigera at 100 mg/L showed significant reduction in chlorophyll, epidermal polyphenol content and photochemical efficiency of P. glandulosa. In contrast, the application of bimetallic Cu/Ag-NP from J. spicigera showed a positive impact on physiological parameters of P. glandulosa after 72 h of exposure.

International audience; This work introduces a new vision-based approach for estimating chlorophyll contents in a plant leaf using reflectance and transmittance as base parameters. Images of the top and underside of the leaf are captured. To estimate the base parameters (reflectance/transmittance), a novel optical arrangement is proposed. The chlorophyll content is then estimated by using linear regression where the inputs are the reflectance and transmittance of the leaf. Performance of the proposed method for chlorophyll content estimation was compared with a spectrophotometer and a Soil Plant Analysis Development (SPAD) meter. Chlorophyll content estimation was realized for Lactuca sativa L., Azadirachta indica, Canavalia ensiforme, and Lycopersicon esculentum. Experimental results showed that-in terms of accuracy and processing speed-the proposed algorithm outperformed many of the previous vision-based approach methods that have used SPAD as a reference device. On the other hand, the accuracy reached is 91% for crops such as Azadirachta indica, where the chlorophyll value was obtained using the spectrophotometer. Additionally, it was possible to achieve an estimation of the chlorophyll content in the leaf every 200 ms with a low-cost camera and a simple optical arrangement. This non-destructive method increased accuracy in the chlorophyll content estimation by using an optical arrangement that yielded both the reflectance and transmittance information, while the required hardware is cheap.

We report here the complete genome sequence of Rhizobium sp. strain ACO-34A, isolated from Agave americana L. rhizosphere. No common nod genes were found, but there were nif genes for nitrogen fixing. A low average nucleotide identity to reported species supports its designation as a novel Rhizobium species that has a complete ribosomal operon in a plasmid.

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.

The influence of Naphtaleneacetic acid (NAA) and 6-Benzylaminopurine (BAP) on callus formation, its morphology and fatty acids profile were examined from Jatropha curcas L. Embryo from seeds of J. curcas L. were sown in Murashige and skoog (MS) medium with NAA and BAP. All treatments induced callus formation, however callus morphology was different in most of the treatments. Higher callus biomass was presented with 1.0 NAA + 0.5 BAP mg/L. Plant growth regulators modifies the fatty acids profile in callus of J. curcas L. BAP was induced linoleic and linolenic acids.

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...

Extraction of oils from castor bean (Ricinus communis L.) and Jatropha curcas L. to produce biofuel is set to increase. The produced seed cake could be applied to soil as it is nutrient rich, but might affect soil functioning. Seven soils from Chiapas, Mexico, were amended with seed cake of both plants while CO 2 , CH 4 and N 2 O emissions and mineral N concentrations were monitored in an aerobic incubation. The concentration of phorbol esters in the J. curcas seed cake (JSC) was 0.993 mg/g while no ricin was detected in the R. communis seed cake (RSC). Application of JSC increased CO 2 emission 2.5-times, N 2 O 12.6-times and CH 4 18.4-times compared to the unamended soil, while RSC CO 2 emission 2.1-times, N 2 O 21.3-times and CH 4 2.3-times. On average, 66% of the 88 mg organic N added with JSC was mineralized and 83% of the 101 mg organic N of the RSC within 56 days. It was found that J. curcas and castor bean seed cake increased CO 2 , CH 4 and N 2 O emission and mineral N in soil, without inhibiting soil microbial activity.

Vermicompost and worm-bed leachate (WBL) are two products obtained from vermicomposting. The objective of this study was to evaluate the effect of different combinations of vermicompost and WBL on cultivating radish (Raphanus sativus L.). A multilevel factorial design with 25 treatments was used to investigate the effect of vermicompost at 0, 10, 20, 30, or 40% and WBL at 0, 10, 20, 30, or 40% on germination and growth parameters. A maximum seed germination of 54%, number of leaves (2.8), and plant height (8.6 cm) were obtained with 10% vermicompost and 10% WBL. A maximum shoot (7.0 g) and root (7.3 g) dry weight was obtained with 10% vermicompost and 15% WBL. Vermicompost and worm-bed leachate have an inhibitory effect at higher concentrations on seed germination and plant growth. These inhibitory effects might be due to increased salt concentrations, pH or auxin-like effects of humic and fulvic acids.

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.

Aims: To characterize the bacterial community of taberna, an alcoholic traditional beverage from the Southern part of Mexico produced by the fermentation of the coyol palm sap (Acrocomia aculeate). Methods and Results: Bacterial 16S rDNA libraries were constructed from metagenomic DNA extracted during the fermentation process at 0, 60 and 108 h. A total of 154 clones were sequenced, and 13, 10 and nine unique sequences were found at each sampling time. At the onset of the fermentation, Zymomonas mobilis, Fructobacillus spp., Pantoea agglomerans and other Gammaproteobacteria were detected. After 60 h, lactic acid bacteria were found and 30% of clones in the library were related to Lactobacillus nagelii, L. sucicola and L. sp. By the end of the experiment, i.e. after 108 h, the bacterial community included Z. mobilis, Lact. nagelii and Acetobacter pasteurianus. Conclusions: Our results suggest that Z. mobilis population represented an important proportion of the bacterial community (60–80%), as well as the lactobacilli during the fermentation process. The bacterial diversity was low and decreased as the fermentation progressed. Significance and Impact of the Study: This culture-independent study suggests that Z. mobilis and lactobacilli play an important role in the alcoholic fermentation of the taberna beverage.

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

This paper reports on the optimum concentrations of naphthalene acetic acid (NAA) and 6-benzyladenine (BA) to stimulate callus growth and NAA; kinetin and silver nitrate (AgNO3) for callus redifferentiation in Dianthus caryophyllus L. Meristems were excised and placed in MS medium with 30 g l−1 sucrose and 9.0 μM 2,4-d. Callus clusters were transferred to MS medium containing NAA (0, 1.7, 3.3, and 5.0 μM) and BA (0, 1.7, 3.3, and 5.0 μM) for proliferation and to MS medium with 30 g l−1 sucrose, 2.5 g l−1 phytagel, kinetin (0, 33, and 66 μM); NAA (0, 7.95, and 15.9 μM) and AgNO3 (0, 23.54 and 47.08 μM) for shoot and root induction. Treatments were applied according to a Box–Behnken design. After callus growth and redifferentiation, plants were incubated in the greenhouse at 18 ± 2°C for 4 wk and at 20–26°C for 4 wk. Finally, plants were changed to near-commercial greenhouse conditions with different day (30–35°C) and night (16–24°C) temperatures. Results showed better callus growth at higher NAA concentrations. A maximum callus weight was found with 5.0 μM NAA but without BA. A maximum of 78% calluses with shoots was obtained with 15.9 μM NAA, 47.08 μM AgNO3, and 0.74 μM kinetin and 58% with roots with 15.7 μM NAA and 47.08 μM AgNO3, but without kinetin. The shoots obtained showed little hyperhydricity. Vigorous plants were obtained after gradual acclimatization with an 80% survival rate under nursery conditions.

Extracts of neem (Azadirachta indica A. Juss.) and Gliricidia sepium Jacquin, locally known as 'mata-raton', are used to control pests of maize. Their application, however, is known to affect soil microorganisms. We investigated if these extracts affected emissions of methane (CH4), carbon dioxide (CO2) and nitrous oxide (N2O), important greenhouse gases, and dynamics of soil inorganic N. Soil was treated with extracts of neem, mata-raton or lambda-cyhalothrin, used as chemical control. The soil was amended with or without urea and incubated at 40% and 100% water holding capacity (WHC). Concentrations of ammonium (NH4+), nitrite (NO2(-)) and nitrate (NO3(-)) and emissions of CH4, CO2 and N2O were monitored for 7d. Treating urea-amended soil with extracts of neem, mata-raton or lambda-cyhalothrin reduced the emission of CO2 significantly compared to the untreated soil with the largest decrease found in the latter. Oxidation of CH4 was inhibited by extracts of neem in the unamended soil, and by neem, mata-raton and lambda-cyhalothrin in the urea-amended soil compared to the untreated soil. Neem, mata-raton and lambda-cyhalothrin reduced the N2O emission from the unamended soil incubated at 40%WHC compared to the untreated soil. Extracts of neem, mata-raton and lambda-cyhalothrin had no significant effect on dynamics of NH4(+), NO2(-) and NO(3)(-). It was found that emission of CO2 and oxidation of CH4 was inhibited in the urea-amended soil treated with extracts of neem, mata-raton and lambda-cyhalothrin, but ammonification, N2O emission and nitrification were not affected.

The effects of earthworm-processed sheep manure (vermicompost) on growth, productivity, and characteristics of bell pepper fruits (Capsicum annum) (cv ‘Ancho supremo’) were investigated in a greenhouse experiment. Six treatments were applied combining vermicompost and soil in 0:1, 1:1, 1:2, 1:3, 1:4, and 1:5 (v/v) ratios. Plant characteristics were measured 21 and 90 days after transplanting. Addition of vermicompost increased plant size significantly with 8 cm in the 1:3 vermicompost: soil treatment compared to the unamended soil after 21 days, but no significant differences were found after 90 days. Seven more flowers were found in the 1:2 vermicompost: soil treatment and four in the 1:3 vermicompost: soil treatment compared to the unamended soil after 90 days. The number of marketable fruits per plant was significantly 1.5 and 1.9 times greater in the 1:2 and 1:3 vermicompost: soil treatments compared to plants cultivated in unamended soil after 90 days. The addition of vermicompost to soil in...

Extracts of plants have been used to control pests, but little information exists about how effective they are to limit crop damage, or how they affect plant growth, crop yield and insects. Extracts from Azadirachta indica A. Juss. (L.) leaves (NEEM treatment), a plant originating from India known for its bio-insecticide characteristics, and Gliricidia sepium (Jacquin kunth ex Walp.) (GLIRICIDIA treatment), a plant originating from Mexico and Central America known to repel insects, were compared to a standard insecticide, lambda-cyalothrin or Karate ® (CHEMICAL treatment) for insect pest efficacy in cultivated maize in Chiapas, Mexico. Untreated maize plants served as control (CONTROL treatment). Plant damage, crop growth, yield and fauna were monitored during four growing seasons from 2003 to 2006. Mean maize yield was significantly higher in the NEEM and CHEMICAL treatments, i.e. 9784 and 9916 kg ha −1 , respectively, compared to the CONTROL treatment (7206 kg ha −1 ). The GLIRICIDIA treatment yielded 8747 kg ha −1 . Of the 26 insect species found during the growing season, only the number of Spodoptera frugiperda (Lepidoptera: Noctuidae), Macrodactylus spp. (Coleoptera: Melolonthidae) and Frankliniella spp. (Thysanoptera: Thripidae) was significantly different between the treatments, with the lowest values found in the chemical treated plots. The amount of beneficial insects was not affected by treatment, while the amount of insects that cause damage was significantly lower (ca. 2-fold) in the CHEMICAL treatment than in the other treatments. Mean damage to the newly formed leaves was 18% in the NEEM treatment and 23% in the GLIRICIDIA treatment and significantly lower than that of the CONTROL treatment (37%), but significantly higher than that of the CHEMICAL treatment (11%). It was found that leaf extracts of G. sepium and A. indica reduced damage to the newly formed leaves and increased yields compared to untreated maize plants, with neem being more effective. However, neem was not as effective as chemical control with lambda-cyalothrin, for overall maize protection.

An orthogonal experimental design L9 (34) in triplicate was used to optimize the osmotic drying process of jicama or Yam bean (Pachyrhizus erosus). The effect of sucrose content, temperature, time of submerging and thickness of the fruit, on the osmotic drying process of Yam bean were tested. Maximal water loss was obtained when 10 mm fruit slices were submerged in a sucrose concentration of 60° Brix maintained at 60 °C for 2 h, while maximum impregnation was obtained when 5-mm slices were submerged in a 50° Brix solution maintained at 60 °C for 6 h.

The effects of earthworm-processed sheep-manure (vermicompost) on the growth, productivity and chemical characteristics of tomatoes (Lycopersicum esculentum) (c.v. Rio Grande) were investigated in a greenhouse experiment. Five treatments were applied combining vermicompost and soil in proportions of 0:1, 1:1, 1:2, 1:3, 1:4 and 1:5 (v/v). Growth and yield parameters were measured 85 days and 100 days after transplanting. Addition of vermicompost increased plant heights significantly, but had no significant effect on the numbers of leaves or yields 85 days after transplanting. Yields of tomatoes were significantly greater when the relationship vermicompost:soil was 1:1, 1:2 or 1:3, 100 days after transplanting. Addition of sheep-manure vermicompost decreased soil pH, titratable acidity and increased soluble and insoluble solids, in tomato fruits compared to those harvested from plants cultivated in unamended soil. Sheep-manure vermicompost as a soil supplement increased tomato yields and soluble, insoluble solids and carbohydrate concentrations.

Native rhizobia are ideal for use as commercial legume inoculants. The characteristics of the carrier used to store the inoculants are important for the survival and symbiotic potential of the rhizobia. The objective of this study was to investigate the effects of peat (PEAT), perlite sugarcane bagasse (PSB), carboxymethyl cellulose plus starch (CMCS), and yeast extract mannitol supplemented with mannitol (YEMM) on the survival, nodulation potential and N2 fixation capacity of the native strains Sinorhizobium mexicanum ITTG R7T and Rhizobium calliandrae LBP2-1T and of the reference strain Rhizobium etli CFN42T. A factorial design (4 × 3) with four repetitions was used to determine the symbiotic potential of the rhizobial strains. The survival of the strains was higher for PEAT (46% for strain LBP2-1T, 167% for strain CFN42T and 219% for strain ITTG R7T) than for the other carriers after 240 days, except for CFN42T kept on CMCS (225%). All the strains kept on the different carriers effectively nodulated common bean, with the lowest number of nodules found (5 nodules) when CFN42T was kept on CMCS and with the highest number of nodules found (28 nodules) when ITTG R7T was kept on PSB. The nitrogenase activity was the highest for ITTG R7T kept on PEAT (4911 μmol C2H4 per fresh weight nodule h−1); however, no activity was found when the strains were kept on YEMM. Thus, the survival and symbiotic potential of the rhizobia depended on the carrier used to store them.

This study aimed to evaluate the removal of polychlorinated biphenyls, with a vermicomposting system, using the following as components: the earthworm Eisenia fetida, peat moss and rabbit excrement and a compound called decachlorobiphenyl, for a period of 91 days under non-sterile conditions. The results obtained were a removal of decachlorobiphenyl 79.6 % with an initial concentration of 100 mg L−1, 89.7 % with 150 mg L−1 and 95.38 % with 200 mg L−1; the earthworms bioaccumulated less than 5 mg L−1 in all concentrations of decachlorobiphenyl analysed without apparent toxic effect. Weight gain was observed in earthworms that assimilated contaminant during vermicomposting, as the number of cocoons produced in contrast to the control in which both the weight and the number of cocoons were lower. To our knowledge, this is the first study which suggests that vermicomposting may be a suitable mechanism for removal of decachlorobiphenyl with high recalcitrance from contaminated sediment or soils.