A Comparison of Immediate and Short-Term Defensive Responses to Phytophthora Species Infection in Both Susceptible and Resistant Walnut Rootstocks.

Clonal rootstocks are one alternative used by the walnut industry to control damage caused by Phytophthora species, traditionally using plants grafted on susceptible Juglans regia rootstock. Vlach, VX211, and RX1 are clonal rootstocks with a degree of resistance to Phytophthora species. The resistance to pathogens in these rootstocks depends on the resistance mechanisms activated by the presence of the pathogen and subsequent development of responses in the host. In this work, we analyzed how plants of J. regia, Vlach, VX211, and RX1 responded to inoculation with Phytophthora cinnamomi or Phytophthora citrophthora isolates obtained from diseased English walnut plants from Chilean orchards. After inoculation, plants of Vlach, VX211, and RX1 showed canopy and root damage indexes that did not differ from noninoculated control plants. In contrast, plants of J. regia, which is susceptible to P. cinnamomi and P. citrophthora, died after inoculation. Vlach, VX211, and RX1 plants inoculated with P. cinnamomi or P. citrophthora showed greater root weight and volume and greater root growth rates than their respective controls. These results suggest that short-term carbohydrate dynamics may be related to the defense mechanisms of plants; they are immediately activated after inoculation through the production of phenolic compounds, which support the further growth and development of roots in walnut clonal rootstocks. To our knowledge, this is the first study that comprehensively characterizes vegetative and radicular growth and the dynamics of sugars and phenols in response to infection with P. cinnamomi or P. citrophthora in walnut rootstocks.

Accidental Poisoning with Nerium Oleander in Dairy Goat in the Santiago Metropolitan Region in Chile / Intoxicación accidental con Nerium oleander en lechería caprina en la Región Metropolitana de Santiago en Chile / Intoxicação acidental com oleandro de Nerium em laticínios de cabras na região metropolitana de Santiago, no ChileResumo

Abstract A small dairy goat farm in central Chile stocked their troughs with ornamental plants and grasses, which were obtained after pruning the gardens of neighboring sectors. Twelve hours after the goats ingested this food, the farm registered a death toll of eight goats, all of which were adult females in their productive stage, before entering the milking parlor. The mortality episode lasted 84 hours and produced mortality and morbidity values of 48 and 54 percent, respectively (n = 52). During a visit to the farm, clinic inspections, autopsies, and sample tissues were obtained for microscopic analysis (the tissues specimens were fixed in 10% buffered formaldehyde solution). The clinic inspection and microscopic analysis both confirmed that the animals had cardiovascular disease. The lesions were compatible with those produced by cardiac glycosides. During the site visit, Nerium oleander was found in the troughs, which suggested that the animals were poisoned by eating this plant. There was a high presence of this plant in the poisoned area, and it was not associated with the mortality episode before the on-site visit, which indicates that the authors should conduct training and inform producers about the handling and feeding of their animals.

Resumen En establecimiento de pequeño productor caprino (n = 52) en la zona central de Chile, se les administraron en comederos plantas ornamentales y pastos que fueron obtenidos posterior a la poda de jardines en sectores aledaños. A las 12 horas post ingesta de este alimento se encuentran 8 caprinos, hembras, adultos, productivos muertos previo al ingreso a sala de ordeña. El episodio de mortandad se extendió por 84 horas generando una mortalidad del 48 % y una morbilidad del 52 %. Se realizó visita, inspección clínica, necropsia y análisis microscópico de especímenes fijados en solución formolada tamponada al 10 %. La inspección clínica confirma la presencia de animales con afección cardiovascular, al igual que el análisis microscópico. Las lesiones son compatibles con las producidas por glucósidos cardiotóxicos, al recorrer el lugar se observa la presencia de Nerium oleander en comederos de lote afectado, lo que sugiere la intoxicación de estos animales. La presencia de esta planta en la zona de la intoxicación es elevada y antes de nuestra visita no fue asociada al episodio de mortandad, lo que nos indica que se debe realizar capacitación e informar a productores sobre el manejo y alimentación de sus animales.

Resumo No estabelecimento de um pequeno produtor de cabras (n = 52) na zona central do Chile, plantas ornamentais e pastagens foram administradas em alimentadores que foram posteriormente podados por jardins em setores próximos. Às 12 horas após a ingestão deste alimento, são oito cabras, fêmeas, adultos, mortos produtivos antes de entrar na sala de ordenha. O episódio da morte prolongou-se por 84 horas, gerando uma mortalidade de 48% e uma morbidade de 52%. Foram realizadas visita, inspeção clínica, necropsia e análise microscópica das amostras fixadas em solução formolada tamponada a 10%. A inspeção clínica confirmou a presença de animais com doença cardiovascular e a análise microscópica. As lesões são compatíveis com as produzidas pelos glicosídeos cardiotóxicos, ao atravessar o local, observa-se a presença de oleandro de Nerium nos alimentadores do lote afetado, o que implica na intoxicação desses animais. A presença desta planta na zona de envenenamento é alta e, antes da nossa visita, não estava associada ao episódio da morte, o que indica que o treinamento deve ser realizado e informa os produtores sobre o manuseio e a alimentação de seus animais.

Dual function of amino acid ionic liquids (Bmim[AA]) on the degradation of the organophosphorus pesticide, Paraoxon®.

The synthesis of a series of ionic liquids using 1-butyl 3-methylimidazolium (Bmim+) as a cation and different amino acids (AA) as anions (Bmim[AA]) is described. These ILs were used for the first time as reaction media to achieve more eco-friendly Paraoxon degradation. The results show that the degradation of Paraoxon in these Bmim[AA]s is accomplished with great efficiency and without an extra nucleophilic agent. Therefore, we propose that all the Bmim[AA]s used in this study have a dual role in the outcome of this reaction; as a nucleophile and a solvent to carry out degradation of the organophosphorous pesticide, Paraoxon. Both kinetics and product distribution results found in this study for Paraoxon degradation turned out to be promising, because this process is achieved in a reaction medium with a better environmental profile.

Correction: Reaction mechanisms in ionic liquids: the kinetics and mechanism of the reaction of O,O-diethyl (2,4-dinitrophenyl) phosphate triester with secondary alicyclic amines.

Correction for 'Reaction mechanisms in ionic liquids: the kinetics and mechanism of the reaction of O,O-diethyl (2,4-dinitrophenyl) phosphate triester with secondary alicyclic amines' by Paulina Pavez et al., Org. Biomol. Chem., 2016, DOI: 10.1039/c5ob02128f.

Reaction mechanisms in ionic liquids: the kinetics and mechanism of the reaction of O,O-diethyl (2,4-dinitrophenyl) phosphate triester with secondary alicyclic amines.

The reactions of O,O-diethyl 2,4-dinitrophenyl phosphate triester (1) with secondary alicyclic (SA) amines in the ionic liquids [Bmim]BF4 and [Bmim]DCA were subjected to a kinetic study. Eyring plots were obtained for the title reactions in the above ionic liquids (ILs) and also in aqueous ethanol (44 wt% ethanol). Two different reaction pathways were observed in [Bmim]BF4: nucleophilic attack at the phosphoryl center, SN2(P), and at the C-1 aromatic carbon, SN(Ar), where the product distribution remained constant and independent of the amine nature. In contrast, in [Bmim]DCA only the SN2(P) pathway was found. From the kinetic analysis of the SN2(P) pathway in both ILs, curved upwards plots of kobsdvs. 1-formylpiperazine concentration were obtained. Based on the kinetic behavior, a change in the mechanism of the SN2(P) pathway is proposed for the aminolysis of 1, from a concerted process in aqueous ethanol to a stepwise mechanism, through a zwitterionic pentacoordinate intermediate, when [Bmim]BF4 and [Bmim]DCA are used as the solvents of the reaction.

Toward a pK(a) scale of N-base amines in ionic liquids.

An electrochemical technique was used to investigate pKa values of some substituted secondary alicyclic (SA) amines, pyridines (py), anilines (AN), and triethylamine (Et3N) in different ionic liquids. The method involves cyclic voltammetry at a platinized Pt electrode. The experimental data were correlated with pKa values reported previously in aqueous solution, and Hammett parameters were correlated with pKa values in ionic liquids to determine ρ values in these media.

Mechanisms of degradation of paraoxon in different ionic liquids.

Herein, the reactivity and selectivity of the reaction of O,O-diethyl 4-nitrophenyl phosphate triester (Paraxon, 1) with piperidine in ionic liquids (ILs), three conventional organic solvents (COS), and water is studied by (31)P NMR, UV-vis, and GC/MS. Three phosphorylated products are identified as follows: O,O-diethyl piperidinophosphate diester (2), O,O-diethyl phosphate (3), and O-ethyl 4-nitrophenyl phosphate diester (4). Compound 4 also reacts with piperidine to yield O-ethyl piperidinophosphate monoester (5). The results show that both the rate and products distribution of this reaction depend on peculiar features of ILs as reaction media and the polarity of COS.