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A combination of two compatible micro-organisms, Trichoderma harzianum and Streptomyces rochei, both antagonistic to the pathogen Phytophthora capsici, was used to control root rot in pepper. The population of the pathogen in soil was reduced by 75% as a result. Vegetative growth of the mycelium of P. capsici was inhibited in vitro on the second day after P. capsici and T. harzianum were placed on the opposite sides of the same Petri plate. Trichoderma harzianum was capable of not only arresting the spread of the pathogen from a distance, but also after invading the whole surface of the pathogen colony, sporulating over it. Scanning electron microscopy showed the hyphae of P. capsici surrounded by those of T. harzianum, their subsequent disintegration, and the eventual suppression of the pathogen's growth. Streptomyces rochei produced a zone of inhibition, from which was obtained a compound with antioomycete property secreted by the bacteria. When purified by high-pressure liquid chromatography, this compound was identified as 1-propanone, 1-(4-chlorophenyl), which seems to be one of the principal compounds involved in the antagonism. A formulation was prepared that maintained the compound's capacity to inhibit growth of the pathogen for up to 2 years when stored at room temperature in the laboratory on a mixture of plantation soil and vermiculite. The two antagonists, added as a compound formulation, were effective at pH from 3.5 to 5.6 at 23-30°C. The optimal dose of the antagonists in the compound formulation was 3.5 · 10 8 spores/ml of T. harzianum and 1.0 · 10 9 FCU/ml of S. rochei. This is the first report of a compound biocontrol formulation of these two antagonists with a potential to control root rot caused by P. capsici.

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Bioactive phytoprostanes and phytofurans are synthesized in higher plants by non‐enzymatic oxidation of α‐linolenic acid (C18:3 n‐3), triggered by high concentrations of reactive oxygen species. In the current scenario of changing dietary patterns, additional information is needed on the concentrations of oxylipins in legumes and on the effect of sustained deficit irrigation on their concentration. The main objective of the work is to elucidate the phytoprostane and phytofuran profile (including eight and three compounds, respectively) of three Pisum sativum cultivars (“mangetout” (ssp. arvense), “BGE‐033620,” and “Lincoln”) and Phaseolus vulgaris (French bean cv. “Helda”), to unravel the oxidative response of these crops to sustained irrigation deficit in terms of oxidative stress, as well as in their importance as healthy dietary sources of new bioactive compounds. Phytoprostanes and phytofurans vary between varieties and species, with 9‐F1t‐PhytoP and ent‐16‐(RS)‐13‐epi‐ST‐Δ14‐9‐PhytoF being the most abundant. The level of phytoprostanes and phytofurans is also determined in sustained deficit irrigation (50% water needed), revealing modifications of their profile and concentration. In conclusion, bioactive phytoprostanes and phytofurans are present in legumes in high concentrations, being further modified by abiotic stress growing conditions, highlighting the importance of this plant food as a dietary source of these bioactive molecules. Practical Applications: This work is of high relevance from the lipidomic point of view, given that phytoprostanes and phytofurans have been promoted as new bioactive secondary metabolites due to their structural analogy with mammal oxylipins. These compounds can be further postulated as possible markers for the monitoring of the physiological status of legume plants under different agronomical conditions. The results obtained can contribute to the successful development of future research in the field of plant physiology and nutrition, significantly contributing to the advance of the current knowledge on the biological role of phytoprostanes and phytofurans in plants and complex biological systems. Species‐dependent modification of phytoprostanes and phytofurans by deficit irrigation in French‐bean, pea, and mangetout.

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