Induced systemic resistance (ISR) is a mechanism involved in the plant defense response against pathogens. Certain members of the Bacillus genus are able to promote the ISR by maintaining a healthy photosynthetic apparatus, which prepares the plant for future stress situations. The goal of the present study was to analyze the effect of the inoculation of Bacillus on the expression of genes involved in plant responses to pathogens, as a part of the ISR, during the interaction of Capsicum chinense infected with PepGMV. The effects of the inoculation of the Bacillus strains in pepper plants infected with PepGMV were evaluated by observing the accumulation of viral DNA and the visible symptoms of pepper plants during a time-course experiment in greenhouse and in in vitro experiments. The relative expression of the defense genes CcNPR1, CcPR10, and CcCOI1 were also evaluated. The results showed that the plants inoculated with Bacillus subtilis K47, Bacillus cereus K46, and Bacillus sp. M9 had a reduction in the PepGMV viral titer, and the symptoms in these plants were less severe compared to the plants infected with PepGMV and non-inoculated with Bacillus. Additionally, an increase in the transcript levels of CcNPR1, CcPR10, and CcCOI1 was observed in plants inoculated with Bacillus strains. Our results suggest that the inoculation of Bacillus strains interferes with the viral replication, through the increase in the transcription of pathogenesis-related genes, which is reflected in a lowered plant symptomatology and an improved yield in the greenhouse, regardless of PepGMV infection status.

The aim of this study was to evaluate the effect of inoculation with Bacillus spp. isolates on the photosynthetic apparatus of Capsicum chinense plants infected with PepGMV. In vitro and greenhouse experiments were performed to evaluate whether the inoculation improved plants’ performance through the increase in photosynthetic efficiency to control PepGMV. The results showed that despite PepGMV infection, the plants inoculated with some isolates of Bacillus spp. had a healthy photosynthetic mechanism, as the photochemical parameters and gas exchange increased. The maximum photochemical quantum yield of PSII (Fv/Fm) of plants with PepGMV and inoculated with Bacillus isolates (M9, K46, and K47) increased (7.85, 7.09, and 7.77%, respectively) with respect to uninoculated controls. In inoculated plants, the CO₂ assimilation rate increased and the transpiration rate decreased, therefore indicating an increased water use efficiency. This effect was reflected by the less severe symptoms caused by PepGMV in the plants obtained from seeds inoculated with different Bacillus spp. Plants inoculated with K47 isolates showed an increase in fruit yield and quality. This study suggests that it is possible to protect, at the greenhouse level, C. chinense plants from PepGMV through selected rhizobacteria inoculation.

White leg shrimp (Litopenaeus vannamei) is a widely cultured species along the Pacific coast and is one of the most important crustaceans in world aquaculture. The microbiome composition of L. vannamei has been previously studied in different developmental stages, but there is limited information regarding the functional role of the microbiome during the development of L. vannamei. In this study the metatranscriptome in different developmental stages of L. vannamei (larvae, juvenile and adult) were generated using next generation sequencing techniques. The bacterial phyla found throughout all the stages of development belonged to the Proteobacteria, Firmicutes and Actinobacteria, these bacterial phyla are present in the digestive tract and are capable of producing several hydrolytic enzymes, which agrees with high representation of the primary metabolism and energy production, in both host and the microbiome. In this sense, functional changes were observed as the development progressed, in both host and the microbiome, in stages of larvae the most represented metabolic functions were associated with biomass production; while in juvenile and adult stages a higher proportion of metabolic functions associated to biotic and abiotic stress in L. vannamei and the microbiome were shown. This study provides evidence of the interaction of the microbiome with L. vannamei, and how the stage of development and the culture conditions of this species influences the gene expression and the microbiome composition, which suggests a complex metabolic network present throughout the life cycle of L. vannamei.

The aim of this study was to evaluate the concentration and distribution of a number of macro- and micronutrients in response to imbibition in habanero pepper seeds extracted from fruits with different stages of maturity and postharvest storage times, as well as in their seedlings. Fruits were harvested unripe, half-ripe, and ripe, and were subjected to storage for 0 (control), 7, and 14 days postharvest prior to seed extraction. An X-ray microfluorescence analysis was carried out on seeds pre- and post-imbibition, as well as on seedlings at 10 and 14 days after sowing. K, Ca, Fe, P, Mg, and Mn were detected by elemental analysis. The results indicated that the elements had a higher concentration and distribution in seeds extracted from half-ripe fruits and ripe unstored fruits, as well as in seeds extracted from fruits stored for 7 and 14 days postharvest. K and Ca were the elements with the highest distributions and concentrations in seeds and seedlings pre- and post-imbibition compared to the other elements. At all maturity stages, postharvest storage increased the concentration and distribution of mineral nutrients in seeds and seedlings before and after imbibition. Storage translocated mineral elements to the radicle before germination, increased meristem growth in emerged seedlings, decreased electrical conductivity, and increased germination. Fourteen days of postharvest storage increased the distribution of macro- and micronutrients in immature seeds, decreasing electrical conductivity, potentiating germination, and improving mineral element distribution in seedlings.

Fruits of species of the genus Bromelia contain compounds with health benefits and potential biotechnological applications. For example, Bromelia karatas fruits contain antioxidants and proteins with bactericidal activity, but studies regarding the activity of these metabolites and potential benefits are required. We evaluated the bactericidal activity of the methanolic extract (treated and not treated with activated charcoal) and its fractions (hexane, ethyl acetate, and methanol) from ripe B. karatas fruit (8 °Brix) against Escherichia coli, Enterococcus faecalis, Salmonella enteritidis, and Shigella flexneri. The methanolic extract (ME) minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined at eight concentrations. The methanolic extract MIC was 5 mg/mL for E. faecalis and 10 mg/mL for the other bacteria; the MBC was 20 mg/mL for E. coli and E. faecalis, and 40 mg/mL for S. enteritidis and S. flexneri. Through gas chromatography–mass spectrometry, 131 compounds were identified, some of which had previously been reported to have biological activities, such as bactericidal, fungicide, anticancer, anti-inflammatory, enzyme inhibiting, and anti-allergic properties. The most abundant compounds found in the ME of B. karatas fruits were maleic anhydride, 5-hydroxymethylfurfural, and itaconic anhydride. This study shows that B. karatas fruits contain metabolites that are potentially beneficial for health.

El monitoreo nutrimental en cultivos hortícolas representa una herramienta que ayuda a modificar y ajustar las dosis de fertilización originalmente proyectadas. En esta investigación a través de dos experimentos, se identificó la respuesta del cultivo de chile habanero (Capsicum chinense Jacq.) a la aplicación de nitrógeno y su concentración de nitratos en el extracto celular asociada al crecimiento y rendimiento. El primer estudio se realizó bajo condiciones de invernadero y en plántulas. Se estudiaron tres dosis de nitrógeno aplicadas en solución nutritiva y dos dosis de potasio. Se midió el crecimiento y rendimiento del cultivo, así como la concentración de nitratos y potasio en el extracto celular. En el segundo experimento, se estudiaron cuatro dosis de nitrógeno y se midió el rendimiento y la calidad del cultivo manejado en condiciones de campo. Así mismo durante el crecimiento del cultivo se midió la concentración de nitratos en el extracto celular. Los métodos, materiales utilizados, así como los resultados y conclusiones de cada experimento se presentan por separado. De forma general se concluyó que tanto en condiciones de invernadero como en campo a cielo abierto, el monitoreo de los nitratos en el extracto celular en chile habanero es una herramienta que se puede utilizar para hacer ajustes en la fertilización del cultivo a lo largo de su ciclo de crecimiento.