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The objective was to evaluate the effects of In vitro biocontrol of Trichoderma spp. and Bacillus spp. against Fusarium oxysporum and its in vivo effect on Solanum lycopersicum plants. The antagonistic effect in vitro of microcapsules of Trichoderma spp. and Bacillus spp. against F. oxysporum, was evaluated by inhibition and antagonism classification, in the in vivo part growth variables in plant and fruit were measured. Trichoderma asperellum showed inhibition of 84.7% and class 1 and Bacillus spp., obtained an inhibition of 83.7% with a positive classification. The canonical correspondence analysis of the fruit, the T1 treatment indicates that the variables that highlight the effect of the treatment are the firmness of the fruit and the Brix. The canonical correspondence analysis of the plant, the height presents a significant difference (P < 0.05), highlighting B. subtilis, Bacillus liquefasciens, T. harzianum and T. asperellum + Bacillus amiloliquefasciens, with 1.05 and 1.1 m compared to the control of 74 cm, also highlighted the number of total fruits in the T. harzianum treatment with an average of 22.6 fruits and root weight in B. subtilis with 37.12 g. Strains of Trichoderma spp. and Bacillus spp. successfully inhibited F. oxysporum also induced growth in the tomato plant. [ABSTRACT FROM AUTHOR]

The objective was to evaluate the antagonistic effect in vitro of native strains of Trichoderma asperellum, Trichoderma harzianum and two isolates of Bacillus spp. against Fusarium oxysporum and Dickeya chrysanthemi. Bacillus, isolated from soil samples of Aloe vera plantations, was morphologically identified and a modified dual culture confrontation was carried out, placing the F. oxysporum in the center of the Petri dish and Bacillus in the four cardinal points; it was arranged under a completely randomized experimental design with five repetitions, the variables registered were percentage of antagonism, inhibition halo and concentration of conidia. For Trichoderma they were confronted against F. oxysporum and D. chrysanthemi with a dual confrontation, a percentage of inhibition and antagonism classification were determined. In the confrontation of T. asperellum it obtained a percentage of inhibition of 70.5% against F. oxysporum and 41.9% against D. chrysanthemi. Regarding the inhibition halos of Bacillus (B5 and B4), they obtained 4 mm. In the conidia concentration B5 showed 1.3, B4 2.6 and the control 12.6 spores per dilution. Trichoderma and Bacillus represent a viable alternative for the control of F. oxysporum and D. chrysanthemi. [ABSTRACT FROM AUTHOR]

Huanglongbing (HLB) reduces the growth and development of citrus and induces changes in secondary metabolites such as flavonoids, limonoids, and polyamines. Likewise, infected plants have a deficient absorption of nutrients such as zinc, potassium, manganese, and copper. Therefore, the objective of this study was to evaluate the influence of different rootstocks on morphology and mineral changes of Citrus limon and Citrus sinensis cv. Valencia plants inoculated with Candidatus Liberibacter asiaticus. In a greenhouse of the Experimental Station-Autonomous University of Tamaulipas, the Candidatus Liberibacter asiaticus bacteria were inoculated to Citrus limon plants (growing on Citrus volkameriana, Citrus macrophylla, and Citrus aurantium rootstocks) and Citrus sinensis cv. Valencia (growing on Citrus volkameriana and Citrus aurantium rootstocks). The experiment was established under a completely randomized design with 45 graft/rootstock repetitions. In each graft/rootstock combination, the plant height and stem diameter were determined using a tape measurer and a Vernier, respectively. In addition, the nutrient content of foliar samples was determined by an X-ray fluorescence spectrometer. In both citrus species, the C. aurantium rootstock promoted a higher concentration of the bacteria. On the other hand, the rootstock that showed the best agronomical results after inoculation with the bacteria was C. volkameriana, presenting the least variation in mineral content and conferring greater plant height (15%) and stem diameter (23%). In contrast, the presence of Ca. Liberibacter asiaticus decreased S content and increased Cu concentration in C. lemon plants. Similarly, plants infected with C. sinensis presented higher Fe content. Finally, in both species, no significant differences were observed for Mn, P, and Zn concentration. [ABSTRACT FROM AUTHOR]

Pollutants and microbiota present in the residual sludge of hydraulic fracturing were determined and characterized physicochemically. Analyses included determination of pH, electric conductivity, organic matter percentage, as well as total carbonates, inorganic nitrogen and extractable phosphorous. In addition, presence of hydrocarbons by gas chromatography, potentially toxic elements (PTEs) by atomic absorption and presence of radioactive isotopes by gamma spectrometry were determined. Moreover, fungi and bacteria present in the residual sludge were classified taxonomically to the level of genus. Medium and heavy hydrocarbon fractions were found in concentrations above the maximum limits permitted (MLP) by Mexican environmental norms. Cu, Pb, Zn, Fe and Mg, however, were below the MLP. Likewise, gamma spectrometry analysis revealed naturally occurring Ac228, Ra226 and K40. The microbiological analysis found presence of the bacteria Bacillus spp., Micrococcus sp., Diplococcus sp. and Staphylococcus sp. and the fungi Trichoderma sp., Aspergillus sp. and Penicillium spp. [ABSTRACT FROM AUTHOR]

Five samples of agricultural soil and five samples of Aloe barbadensis (P. Mill., 1768) plants with symptoms of wilt and root necrosis were collected in five localities of the state of Tamaulipas, México. The aims of this study were the morphological identification, molecular identification and in vitro evaluation of the antagonistic activity of Trichoderma spp. on Fusarium spp. Four strains of Trichoderma asperellum, one strain of Trichoderma harzianum and five strains of Fusarium oxysporum were identified by morphological and molecular methods. The evaluation of the antagonistic activity of T. harzianum isolate (TP) showed the highest inhibition in Fusarium spp. (78.80%). The evaluation of the antagonistic activity of Trichoderma spp. extracts in Fusarium spp. did not show significant differences between treatments (P ≤ 0.05), with Trichoderma growth percentages that oscillated between 81.08 and 94.38%. The native isolate of T. harzianum (TP) showed significant competitive capability against the mycelial growth of F. oxysporum. Trichoderma species are promising agents of biological control in the central area of the State Tamaulipas, Mexico. [ABSTRACT FROM AUTHOR]

This article highlights the importance of native bacteria in the bioremediation of sites affected by oil spills. Hydrocarbons released in oil spills are a source of contamination for aquatic and terrestrial ecosystems due to their persistence in the environment and are considered highly toxic, causing serious damage to human health as well as to the flora and fauna of the affected sites. In order to mitigate the negative effects caused by oil This article highlights the importance of native bacteria in the bioremediation of sites affected by oil spills. Hydrocarbons released in oil spills are a source of contamination for aquatic and terrestrial ecosystems due to their persistence in the environment and are considered highly toxic, causing serious damage to human health as well as to the flora and fauna of the affected sites. In order to mitigate the negative effects caused by oil. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the insecticidal activity of the polyphenolic compounds found in neem on S. frugiperda larvae. Three neem extracts (1:12 (m/v) with 70% ethanol, 1:12 (m/v) with 0% ethanol (only water), and 1:4 (m/v) with 0% ethanol) were employed. Subsequently, the extraction of phytochemical compounds of each extract was performed using ultrasound and microwave technologies simultaneously. The compound characterization was performed by HPLC-mass. In addition, the insecticidal evaluation of the neem extract was performed against S. frugiperda of the second-stage larvae. The extracts were applied by spraying the larvae according to each bioassay. Results showed that the extract obtained with a 1:12 (m/v) relationship and 70% ethanol was effective for the control of S. frugiperda larvae. In this extract, the predominant organic compound families were: methoxyflavones, flavonols, hydroxycoumarins, anthocyanins, methoxycinnamic acid, and alkylflavones. Phytochemical compounds obtained from neem seeds with environmentally friendly solvents and alternative technologies (ultrasound and microwave) have potent insecticidal activity against S. frugiperda larvae. [ABSTRACT FROM AUTHOR]

Lophophora williamsii (peyote) is a spineless cactus that stands out for its psychoactive alkaloid content and considered vulnerable due to the destruction of its habitat and illegal extraction. The objective of this study is to describe the spatial distribution and interactions between facilitator species and L. williamsii that are important for this species conservation and reintroduction programs. The spatial distribution pattern was determined by Ripley's K-function. To know whether L. williamsii requires facilitator species, 10 plots of 100 m2 each were considered to perform dasometric measurements of the perennial species. Frequency of peyotes under the canopy of perennial species and open spaces was determined. The cardinal directions in which peyote individuals were found under the facilitator species were recorded, as well as soil surface temperature and solar radiation at soil level under the foliage and open spaces. L. williamsii showed an aggregated spatial distribution; 97.7% of peyotes were found under the foliage of facilitator species, where temperature and solar radiation were significantly lower than in the open spaces. Among the facilitator species, those that stand out are Flourensia cernua , Agave lechuguilla , Larrea tridentata , and Prosopis glandulosa. Significantly greater frequencies of peyotes were observed positioned on the northern quadrant of the facilitator crown. The results obtained show that L. williamsii needs the protection of perennial species for its establishment. Thus, the disappearance of these species could put at risk the persistence of peyote in these communities. These findings point out that the conservation and restoration of wild peyote populations require maintenance from the facilitator species. • Florencia cernua was the main facilitator species for Lophophora williamsii. • The highest L. williamsii density population is reported (7570 ind./ha). • Important data for future L. williamsii conservation and restoration planning. [ABSTRACT FROM AUTHOR]

Pectin is a co-product from juicing and the physico-chemical quality is important to functionality of pectin in food and pharmaceutical applications. Juice and peel from Huanglongbing (HLB) control and infected Valencia oranges were analyzed. Infected fruit had smaller diameter, lower L* and b* values and highly variable a* values. Juice from infected fruit had higher pectinmethylesterase (PME) activity of 1.5 Units/mL, which retained higher activity during 15 days of storage at 4 °C, and juice had higher cloud loss. Also, the juice obtained from infected fruit had lower °Brix (8.5–8.9), higher titratable acidity (0.71–0.88%), and lower pH (3.45–3.75). Molecular weights of 154–157 kDa and degrees of esterification of 65–67% were similar. Pectin yield from dried peel was reduced by 6% in infected fruit to 4.18 g/100 g. Total neutral sugars in pectin from control fruit were higher, 84.1 μg/mg, compared to infected fruit, 60.7 μg/mg. Glucose, galactose, and arabinose, were higher in control fruit, 25.0, 40.8, and 9.7 μg/mg, compared to 14.5, 27.4, and 8.3 μg/mg in infected fruit. Viscosity was 0.015 Pa s, in 1% pectin from control or infected fruit (p > 0.05). Juice quality, including cloud stability, was negatively impacted by HLB, however pectin functionality was minimally impacted. • Huanglongbing negatively impacts citrus juice ◦Bx, pH, titratable acidity, color. • Juice from infected fruit has higher pectinmethylesterase activity and cloud loss. • Lower yield of pectin from peel was obtained from infected fruit. • Pectin is similar in control or infected fruit. [ABSTRACT FROM AUTHOR]