1-Methyltryptophan Modifies Apoplast Content in Tomato Plants Improving Resistance Against Pseudomonas syringae

Plants can produce numerous natural products, many of which have been shown to confer protection against microbial attack. In this way, we identified 1-methyltryptophan (1-MT), a natural compound produced by tomato plants in response to Pseudomonas syringae attack, whose application by soil drench provided protection against this pathogen. In the present work, we have studied the mechanisms underlying this protection. The results demonstrated that 1-MT can be considered a new activator of plant defense responses that acts by inhibiting the stomatal opening produced by coronatine (COR) and could thereby, prevent bacteria entering the mesophyll. Besides, 1-MT acts by blocking the jasmonic acid (JA) pathway that, could avoid manipulation of the salicylic acid (SA) pathway by the bacterium, and thus hinder its growth. Although the concentration of 1-MT reached in the plant did not show antimicrobial effects, we cannot rule out a role for 1-MT acting alone because it affects the expression of the fliC gene that is involved in synthesis of the flagellum. These changes would result in reduced bacterium motility and, therefore, infective capacity. The results highlight the effect of a tryptophan derivative on induced resistance in plants

Differential expression and localization of transient receptor potential vanilloid 1 in rabbit and human eyes

Producción CientíficaSummary. Introduction: The superfamily of transient receptor potential (TRP) cation channels is involved in nociception. Members of this family, such as the vanilloid receptor type 1 (TRPV1) channel, are activated by a wide range of stimuli including heat (>43°C), low pH (<6.5), hypoxia, and hypertonicity. Here we report TRPV1 expression in rabbit and human eyes. Material and methods: We analyzed the expression of TRPV1 mRNA by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and protein by immunohistochemistry in eyes of New Zealand White rabbits and humans. Results: In rabbit and human eyes, TRPV1 protein was present in all layers of the corneal epithelium, but only in the basal layer of the conjunctiva. It was also in the ciliary and lens epithelia of both species as well as in the secretory cells of the rabbit lacrimal gland. The retinal pigment epithelium was positive for this protein in both species. TRPV1 was also present in rabbit Müller cells, where it had a similar pattern of expression to vimentin intermediate filaments. Analysis by qRT-PCR showed that TRPV1 mRNA was found in all of the structures where the protein was present. The highest level was in the lens and the lowest in the retina. Conclusion: TRPV1 is expressed in cells that are particularly active in Ca2+ exchange as well as in cells with significant water transport activity. Because TRPV1 is a Ca2+ channel, it probably functions in the regulation of both water and Ca2+ movements in ocular tissues

Acaricide residues in beeswax. Implications in honey, brood and honeybee

15 Pág.For beekeeping to be sustainable, the management of colonies for the production of bee products must be economically viable without endangering the lives of bees, and must include acceptable practices such as the treatment of hives with appropriate products. Occasionally, the use of acaricides to treat the hives against varroosis is uncontrolled and can accumulate in the hives, putting the colonies at risk. In this work, a screening of seven acaricides was carried out in different apiaries in Andalusia (Spain). Their distribution in beeswax, brood, honey, and bees from colonies in different surroundings was evaluated at different times. It was found that beeswax was highly contaminated but honey, brood and bees had acceptable levels, below their respective MRL or LD50, after a certain period following varrocide treatments. Acaricides banned for their use against Varroa, such as chlorfenvinphos, cypermethrin and especially acrinathrin, were found in the hives analysed.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This work was funded by the National Institute for Agricultural and Food Research and Technology (INIA-CSIC) in Spain, Projects AT2017-002 and RTA2017-00058-C04-01.Peer reviewe

Posicionamientos metodológicos de REUNI+D

[spa] El presente texto intenta recoger las principales aportaciones de los grupos de investigación integrantes de REUNI+D, en torno al posicionamiento metodológico frente a los proyectos de investigación educativa que llevan a cabo estos grupos. El debate se desarrolló a través de un foro virtual, abierto a la participación de todos los miembros de la Red. Los objetivos de este foro de debate se focalizan en conocer la diversidad que existe entre los diferentes grupos de investigación, compartiendo los enfoques metodológicos utilizados, los autores y modelos de referencia y las claves para utilizar un determinado posicionamiento y si es posible llegar a consensuar posicionamientos en la Red.[cat] El document que presentem intenta recollir les principals aportacions dels grups d'investigació integrants de la xarxa REUNI+D, entorn del posicionament metodològic davant els projectes de investigació educativa que duen a terme aquests grups. El debat es va desenvolupar a través d'un fòrum virtual, obert a la participació de tots els membres de la Xarxa. Els objectius d'aquest fòrum de debat es centren en conèixer la diversitat existent entre els diferents grups d'investigació, compartint els enfocs metodològics utilitzats, els autors i els models de referència i les claus per a utilitzar un determinat posicionament, i possiblement arribar a consensuar posicionaments dins de la Xarxa.[eng] This document brings together the main contributions shared by the research groups who form part of REUNI+D, regarding the methodological positions they adopt when carrying out educational research. This content was developed in a debate that took place in a virtual forum open to all network members. The main aim of this debate was to make explicit the diversity that existed within the different research groups, sharing the different methodological frameworks used, as well as the different authors, main references and key points behind each position. If possible, the debate tried to find common ground among groups in order to arrive at a consensus about the methodological position

Influence of leaching medium and drying time between successive leaching periods on the emission of chromium, copper, and boron from treated wood

Laboratory studies were conducted to determine leaching of Cu, Cr, and B from pine sapwood treated with Cr-Cu-B (CCB) preservative in different leaching media (ultrapure water [UPW], rainwater [RW], and soil water [SW]), Losses of metals from CCB-treated wood, expressed in percentage of initial content, were always highest for B (11.2-63.5%) and lowest for Cr (0.02-0.36%) in any of the leaching media assayed. Losses of B and Cr from treated wood were not affected by the leaching medium; however, losses of Cu were 1.5 to 2.5 times higher in SW than in UPW and RW The influence of drying time between successive leaching periods on release of metals also was determined. Treated wood was submitted to wetting-drying cycles of 24 h/d, 18 h/d, and 6 h/d in contact with the leaching medium over a total contact time of 276 h. For an equivalent contact period of CCB-treated wood with either UPW or RW, leaching of B was from 1.1 to 1.9 times higher for continual wetting than under intermittent wetting conditions. Leaching of Cu was not affected by the wetting-drying periods when wood was in contact with RW, but it was 1.2 to 1.5 times higher for continual wetting with UPW. In general, leaching of Cr was not affected by the wetting-drying cycles when in contact with UPW or RW. However, when CCB-treated wood was in contact with SW under discontinuous wetting of 6 h/d, Cu and Cr emissions were approximately 1.2 and 2.5 times higher, respectively, than with continuous wetting. This study shows that the type of leaching medium and the drying time between successive wetting periods must be considered when evaluating metal losses from CCB-treated wood during service life

1-methyltryptophan modifies apoplast content in tomato plants improving resistance against Pseudomonas syringae

Plants can produce numerous natural products, many of which have been shown to confer protection against microbial attack. In this way, we identified 1-methyltryptophan (1-MT), a natural compound produced by tomato plants in response to Pseudomonas syringae attack, whose application by soil drench provided protection against this pathogen. In the present work, we have studied the mechanisms underlying this protection. The results demonstrated that 1-MT can be considered a new activator of plant defense responses that acts by inhibiting the stomatal opening produced by coronatine (COR) and could thereby, prevent bacteria entering the mesophyll. Besides, 1-MT acts by blocking the jasmonic acid (JA) pathway that, could avoid manipulation of the salicylic acid (SA) pathway by the bacterium, and thus hinder its growth. Although the concentration of 1-MT reached in the plant did not show antimicrobial effects, we cannot rule out a role for 1-MT acting alone because it affects the expression of the fliC gene that is involved in synthesis of the flagellum. These changes would result in reduced bacterium motility and, therefore, infective capacity. The results highlight the effect of a tryptophan derivative on induced resistance in plants.This work was supported by the Spanish Ministry of Science and Innovation (AGL2013-49023-C03-02-R) and by Pla de Promoció de la Investigació of Universitat Jaume I (P1 1B2013-75, UJI-A2016-09, and UJI-B2017-30), Research Staff Training grant of AG-H (PREDOC/2016/27) of Universitat Jaume I.Peer Reviewe

Viability of honeybee colonies exposed to sunflowers grown from seeds treated with the neonicotinoids thiamethoxam and clothianidin

In this study, honeybee colonies were monitored in a field study conducted on sunflowers grown from seeds treated with the systemic neonicotinoids thiamethoxam or clothianidin. This field trial was carried out in different representative growing areas in Spain over a beekeeping season. The health and development of the colonies was assessed by measuring factors that have a significant influence on their strength and overwintering ability. The parameters assessed were: colony strength (adult bees), brood development, amount of pollen and honey stores and presence and status of the queen. The concentration of residues (clothianidin and thiamethoxam) in samples of beebread and in adult bees was at the level of ng.g-1; in the ranges of 0.10-2.89 ng g-1 and 0.05-0.12 ng g-1; 0.10-0.37 ng g-1 and 0.01-0.05 ng g-1, respectively. Multivariate models were applied to evaluate the interaction among factors. No significant differences were found between the honeybee colonies of the different treatment groups, either exposed or not to the neonicotinoids. The seasonal development of the colonies was affected by the environmental conditions which, together with the initial strength of the bee colonies and the characteristics of the plots, had a significant effect on the different variables studied

A three-year large scale study on the risk of honey bee colony exposure to blooming sunflowers grown from seeds treated with thiamethoxam and clothianidin neonicotinoids

9 Pág.Despite the restriction of the use of neonicotinoids in the EU, including thiamethoxam and clothianidin, the debate over their risk on honey bees has not been fully settled. This study presents results of a three-year study working with 180 honey bee colonies in ten replicates. Colonies were sorted into three treatments (60 colonies per treatment) exposed to sunflower blooms grown from seeds treated with thiamethoxam, clothianidin and a non-treated control. Each colony was assessed at six moments: one before to exposition to sunflower, two during the exposition (short-time risk), two after exposition (medium-time risk) and one after wintering (long-time risk). The health and development of the colonies were assessed by monitoring adult bee population, brood development, status of the queen, food reserves and survival. No significant difference among treatments when raw data was considered. However, when evolution from initial status of the colony was evaluated, a significant difference was observed from the first week of exposure to sunflower blooms. In this period, the number of adult bees and the amount of brood were slightly lower in the bee hives exposed to neonicotinoids, although such differences disappeared in subsequent evaluations. The concentration of residues in samples of beebread and adult bees was at the level of ng·g-1. Magnitude of the effect of the treatment factor on the variability of colony health and development related parameters was low. The most important factor was the hive, followed by the replicate and year, and to a lesser extent the initial strength of the colonies.This study has been carried out in line with the framework of the project RTA2013-00042-C10.Peer reviewe

Characterization of microzooplankton communities in a polluted coastal area integrating high-throughput sequencing and microscopy

The Mediterranean Sea is subjected to strong anthropogenic pressures that may be causing important ecosystem changes, particularly in coastal areas under high anthropogenic pressure. We characterized the composition of the microzooplankton community in a coastal area in the N Alboran Sea (SW Mediterranean) highly impacted by urban wastewater pollution. Two offshore outfalls release urban wastewater to the sea at a 40 m bottom depth, from a nearby town. We applied an integrative taxonomic approach, combining metabarcoding of the mitochondrial COI and the 18S rRNA genes with morphological microscopic identification of organisms, collected with a CalVET net (50 µm mesh). Hydrology was notably affected near the bottom at the vicinity of the submarine emissaries exit, presenting increased temperature and turbidity, and decreased salinity due to the urban freshwater discharge. Nutrient concentrations exceeded the Water Framework Directive limits; however, chlorophyll a concentrations were not very high, due to strong water column stratification. Microzooplankton communities (50-200 µm) were dominated by dinoflagellates (50-80% relative abundance), followed by copepods (copepodites and nauplii), eggs and cysts. We found significant differences in communities’ composition between the coastal shallow area and the offshore waters, driven by pollution and stratification.Consejería de Economía, Innovación y Ciencia de la Junta de Andalucía; Unión Europea, Fondo Europeo de Desarrollo Regional (P20_00743