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Using chemical defoliants to remove cotton leaves represents a groundbreaking shift in cotton cultivation. The mechanization of cotton harvest is increasing, but a substantial amount of foliage that remains on the plant even at maturity is the major barrier for mechanical harvest. Properly completing mechanical and manual harvests requires artificial leaf detachment through defoliants. Still there is no proper defoliant concentration, application times and mechanism of action available. Therefore, the present study aimed to find an effective defoliant and application time to enhance mechanical harvest efficiency, along with a clear description of the mechanism of actions in cotton CO17 (Gossypium hirsutum). The field experiment was conducted during the year 2019-20 and used five concentrations of Thidiazuron defoliant (100, 150, 200, 250 and 300ppm) and Ethephon@0.5% (T2) in cotton variety CO17 to study the physiological, biochemical and hormonal responses at 120, 127 and 134 days after sowing. As a result, the concentrations of plant growth hormones, indole-3 acetic acid (4.9 fold), zeatin (32.7%) and gibberellic acid (7 fold) reduced. In contrast, abscisic acid (48.6%), jasmonic acid (34.9%), salicylic acid (2.15 fold) increased in the T7- Thidiazuron + Diuron (300 ppm) treatment followed by T5-Thidiazuron + Diuron (200 ppm). Additionally, the antioxidant enzymes ascorbate peroxidase, peroxidase, catalase, superoxide dismutase, cellulase in leaves, petiole and bolls were decreased due to defoliant T5- Thidiazuron + Diuron (200 ppm) followed by T7-Thidiazuron + Diuron (300 ppm), indicating that the hormone concentration, antioxidative and hydrolytic enzymes are ruled out and forces the defoliation process.

Background: Gaseous phytohormone ethylene levels are directly influenced by the production of its immediate non-volatile precursor 1-aminocyclopropane-1-carboxylic acid (ACC). Owing to the strongly acidic character of the ACC molecule, its quantification has been difficult to perform. Here, we present a simple and straightforward validated method for accurate quantification of not only ACC levels, but also major members of other important phytohormonal classes – auxins, cytokinins, jasmonic acid, abscisic acid and salicylic acid from the same biological sample. Results: The presented technique facilitates the analysis of 15 compounds by liquid chromatography coupled with tandem mass spectrometry. It was optimized and validated for 10 mg of fresh weight plant material. The extraction procedure is composed of a minimal amount of necessary steps. Accuracy and precision were the basis for evaluating the method, together with process efficiency, recovery and matrix effects as validation parameters. The examined compounds comprise important groups of phytohormones, their active forms and some of their metabolites, including six cytokinins, four auxins, two jasmonates, abscisic acid, salicylic acid and 1-aminocyclopropane-1-carboxylic acid. The resulting method was used to examine their contents in selected Arabidopsis thaliana mutant lines. Conclusion: This profiling method enables a very straightforward approach for indirect ethylene study and explores how it interacts, based on content levels, with other phytohormonal groups in plants.

Background: Gaseous phytohormone ethylene levels are directly influenced by the production of its immediate non-volatile precursor 1-aminocyclopropane-1-carboxylic acid (ACC). Owing to the strongly acidic character of the ACC molecule, its quantification has been difficult to perform. Here, we present a simple and straightforward validated method for accurate quantification of not only ACC levels, but also major members of other important phytohormonal classes – auxins, cytokinins, jasmonic acid, abscisic acid and salicylic acid from the same biological sample. Results: The presented technique facilitates the analysis of 15 compounds by liquid chromatography coupled with tandem mass spectrometry. It was optimized and validated for 10 mg of fresh weight plant material. The extraction procedure is composed of a minimal amount of necessary steps. Accuracy and precision were the basis for evaluating the method, together with process efficiency, recovery and matrix effects as validation parameters. The examined compounds comprise important groups of phytohormones, their active forms and some of their metabolites, including six cytokinins, four auxins, two jasmonates, abscisic acid, salicylic acid and 1-aminocyclopropane-1-carboxylic acid. The resulting method was used to examine their contents in selected Arabidopsis thaliana mutant lines. Conclusion: This profiling method enables a very straightforward approach for indirect ethylene study and explores how it interacts, based on content levels, with other phytohormonal groups in plants.

Banana is a tropical crop cultivated in warm places. Chilling stress in Egypt is making banana crops less productive. Abscisic acid (ABA), a key plant hormone, regulates metabolic and physiological processes and protects plants from a variety of stresses. In vitro growing banana shoots were pre-treated with ABA at four concentrations (0, 25, 50, and 100 mM) and chilled at 5°C for 24 h, followed by a six-day recovery period at 25°C. By comparing ABA treatments to both positive and negative controls, physiological and biochemical changes were investigated. Chilling stress (5°C) caused a considerable increase in lipid peroxidation and ion leakage and reduced photosynthetic pigments in cold-treated plantlets. Increasing the concentration of ABA to 100 µM enhanced the response to chilling stress. ABA had a major effect on mitigating chilling injury in banana shoots by keeping cell membranes stable and lowering the amount of ion leakage and lipid peroxidation. Also, ABA significantly maintained the photosynthetic pigment concentration of banana shoots; accumulated higher amounts of total soluble carbohydrates and proline; and increased DPPH radical scavenging activity. Furthermore, ABA treatment enhanced cold tolerance in chilling-stressed banana shoots through the regulation of antioxidant enzyme activity. Overall, the results show that ABA is a good choice for protecting banana shoots from the damage caused by chilling stress.

Plants are constantly exposed to a variety of different environmental stresses, including drought, salinity, and elevated temperatures. These stress cues are assumed to intensify in the future driven by the global climate change scenario which we are currently experiencing. These stressors have largely detrimental effects on plant growth and development and, therefore, put global food security in jeopardy. For this reason, it is necessary to expand our understanding of the underlying mechanisms by which plants respond to abiotic stresses. Especially boosting our insight into the ways by which plants balance their growth and their defense programs appear to be of paramount importance, as this may lead to novel perspectives that can pave the way to increase agricultural productivity in a sustainable manner. In this review, our aim was to present a detailed overview of different facets of the crosstalk between the antagonistic plant hormones abscisic acid (ABA) and auxin, two phytohormones that are the main drivers of plant stress responses, on the one hand, and plant growth, on the other.

S-Nitrosoglutathione plays a central role in nitric oxide (NO) homeostasis, and S-nitrosoglutathione reductase (GSNOR) regulates the cellular levels of S-nitrosoglutathione across kingdoms. Here, we investigated the role of endogenous NO in shaping shoot architecture and controlling fruit set and growth in tomato (Solanum lycopersicum). SlGSNOR silencing promoted shoot side branching and led to reduced fruit size, negatively impacting fruit yield. Greatly intensified in slgsnor knockout plants, these phenotypical changes were virtually unaffected by SlGSNOR overexpression. Silencing or knocking out of SlGSNOR intensified protein tyrosine nitration and S-nitrosation and led to aberrant auxin production and signaling in leaf primordia and fruit-setting ovaries, besides restricting the shoot basipetal polar auxin transport stream. SlGSNOR deficiency triggered extensive transcriptional reprogramming at early fruit development, reducing pericarp cell proliferation due to restrictions on auxin, gibberellin, and cytokinin production and signaling. Abnormal chloroplast development and carbon metabolism were also detected in early-developing NO-overaccumulating fruits, possibly limiting energy supply and building blocks for fruit growth. These findings provide new insights into the mechanisms by which endogenous NO fine-tunes the delicate hormonal network controlling shoot architecture, fruit set, and post-anthesis fruit development, emphasizing the relevance of NO-auxin interaction for plant development and productivity.

The plant hormone gibberellin (GA) is required at different stages of legume nodule development, with its spatiotemporal distribution tightly regulated. Transcriptomic and bioinformatic analyses established that several key GA biosynthesis and catabolism enzyme encoding genes are critical to soybean (Glycine max) nodule formation. We examined the expression of several GA oxidase genes and used a Förster resonance energy transfer-based GA biosensor to determine the bioactive GA content of roots inoculated with DsRed-labelled Bradyrhizobium diazoefficiens. We manipulated the level of GA by genetically disrupting the expression of GA oxidase genes. Moreover, exogenous treatment of soybean roots with GA3 induced the expression of key nodulation genes and altered infection thread and nodule phenotypes. GmGA20ox1a, GmGA3ox1a, and GmGA2ox1a are upregulated in soybean roots inoculated with compatible B. diazoefficiens. GmGA20ox1a expression is predominately localized to the transient meristem of soybean nodules and coincides with the spatiotemporal distribution of bioactive GA occurring throughout nodule organogenesis. GmGA2ox1a exhibits a nodule vasculature-specific expression pattern, whereas GmGA3ox1a can be detected throughout the nodule and root. Disruptions in the level of GA resulted in aberrant rhizobia infection and reduced nodule numbers. Collectively, our results establish a central role for GAs in root hair infection by symbiotic rhizobia and in nodule organogenesis.

The aim of this research was to evaluate the effect of mepiquat chloride applied at three times and three different doses: in the development, yield and quality of the cultivation of “escabeche” chili pepper (Capsicum baccatumvar. pendulum). In this experiment, a 23 factorial arrangement was used in a randomized complete block statistical design (DBCA) with four replications, the analysis of variance (ANVA) and the Duncan comparison test of means at 5% for the factors and levels were performed. The doses and moments evaluated were: mepiquat chloride at d1: 250; d2: 375 and d3: 500 ppm; application times at m1: 20, m2: 35 and m3: 50 days after transplanting. No statistically significant differences were found for the interaction of the dose x moment factor, nor for the moment factor. However, statistically significant differences were found for the dose factor and its levels in the variables yield and number of fruits per plant, obtaining the highest value in these variables at the doses of 250 and 375 ppm ofmepiquat chloride with a yield of 21,16 –21,07 t ha-1and 23,24 –22,94 fruits plant-1respectively, regardless of the time of application. Therefore, we can say that the application of mepiquat chloride at doses of 250 and 375 ppm had a positive effect on the crop, increasing the yield and number of fruits per plant, regardless of the time of application., El objetivo del presente trabajo fue evaluar el efecto del cloruro de mepiquat aplicado a tres momentos y tres dosis distintas; en el desarrollo, rendimiento y calidad del cultivo de ají escabeche (Capsicum baccatum var. pendulum). En este experimento se utilizó un arreglo factorial de 23 en un diseño estadístico de bloques completos al azar (DBCA) con cuatro repeticiones, se realizó el análisis de varianza (ANVA) y prueba de comparación de medias de Duncan al 5% para los factores y niveles empleados. Las dosis y momentos evaluados fueron: cloruro de mepiquat a d1: 250; d2: 375 y d3: 500 ppm; momentos de aplicación a m1: 20, m2: 35 y m3: 50 días después del trasplante. No se hallaron diferencias estadísticamente significativas para la interacción del factor dosis x momento, tampoco para el factor momento. Se encontraron diferencias estadísticamente significativas para el factor dosis y sus niveles en las variables rendimiento y número de frutos por planta, obteniéndose el mayor valor en dichas variables a las dosis de 250 y 375 ppm de cloruro de mepiquat con un rendimiento de 21,16 – 21,07 t ha-1 y 23,24 – 22,94 frutos planta-1 respectivamente, independientemente del momento de aplicación. Por lo tanto, podemos decir que la aplicación de cloruro de mepiquat a dosis de 250 y 375 ppm tuvo un efecto positivo en el cultivo incrementando el rendimiento y numero de frutos por planta, sin considerar el momento de aplicación.

Besides anthropogenic factors, climate change causes altered precipitation patterns that indirectly affect the increase of heavy metals in soils due to hydrological effects and enhanced leaching (i.e., Cd and Ni), especially in the vicinity of mines and smelters. Phytoextraction is a well-known, powerful “green” technique for environmental clean-up that uses plants to extract, sequester, and/or detoxify heavy metals, and it makes significant contributions to the removal of persistent inorganic pollutants from soils. Poplar species, due to their growth features, high transpiration rate, large biomass, and feasible reproduction represent great candidates for phytoextraction technology. However, the consequences of concomitant oxidative stress upon plant metabolism and the mechanism of the poplar’s tolerance to heavy metal-induced stress are still not completely understood. In this study, cuttings of poplar species (Populus deltoides W. Bartram ex Marshall) were separately exposed to two heavy metals (Cd2+ and Ni2+) that were triple the maximum allowed amount (MAA) (according to national legislation). The aim of the study was to estimate the effects of heavy metals on: (I) the accumulation of free and conjugated polyamines, (II) plant hormones (including abscisic acid-ABA and indole-3-acetic acid-IAA), and (III) the activities of different antioxidant enzymes at root and leaf levels. By using the selected ion monitoring (SIM) mode of gas chromatography with mass spectrometry (GC/MS) coupled with the isotopically labeled technique, amounts of ABA and IAA were quantified, while polyamine amounts were determined by using high-performance liquid chromatography (HPLC) with fluorometric detection after derivatization. The results showed that P. deltoides responded to elevated concentrations of heavy metals in soils by exhibiting metal- and organ-specific tolerance. Knowledge about tolerance mechanisms is of great importance for the development of phytoremediation technology

Due to the continuous increase of the human population, the demand for food production should increase 70-100% in the following years. However, the food security of humanity is affected by several factors, among them pest insects, which are currently controlled through the application of large doses of synthetic insecticides, which generate serious problems in human health, resistance to pests, residues in foods, environmental pollution, outbreaks of secondary pests and reduction in populations of beneficial insects. Given this global scenario, theseproblemsgenerate a greater demand for pest control methods that are efficient and environmentally friendly, so the objective of the present work was to address in a synthetic way the development and progress of research conductedin Mexico on the biological control of pest insects. This review focuses on technologies with a solid ecological basis for the gradual restoration of biodiversity lost in agroecosystems, so promising alternatives for pest control of great relevance in the Mexican countryside are addressed, such as the use of beneficial insects such as parasitoids, predators and entomopathogens that cause the death of pest insects,the use of sterile insect, bioinsecticides, such as microbial pesticides and other entomopathogens, incorporated plant protectors and biochemical pesticides. The demand for techniques related to the biological control of pest insects in Mexico should address the problems of transboundary, exotic, newly introduced pests and those pests that haveremained for several decades in the country, Debido al continuo aumento de la población humana, la demanda de producción de alimentos deberá aumentar 70-100% en los siguientes años. Sin embargo, la seguridad alimentaria de la humanidad es afectada por diversos factores, entre ellos los insectos plaga, que actualmente son controlados mediante la aplicación de grandes dosis de insecticidas sintéticos, los cuales generan graves problemas en la salud humana, resistencia a plagas, residuos en alimentos, contaminación ambiental, brotes de plagas secundariasy reducción en las poblaciones de insectos benéficos. Ante este escenario mundial, esta problemática genera una mayor demanda de métodos de control de plagas que sean eficientes y amigables con el medioambiente, por lo que el objetivo del presente trabajofue abordar de forma sintética el desarrollo y avance de las investigaciones realizadas en México sobre el control biológico de insectos plaga. Esta revisión se enfoca en tecnologías con una sólida base ecológica para la restauración gradual de la biodiversidad perdida en los agroecosistemas, por lo que se abordan alternativas promisorias para el control de plagas de gran relevancia en el campo mexicano, como el uso de insectos benéficos como parasitoides, predadores y entomopatógenos que ocasionan la muerte de los insectos-plaga, el uso del insecto estéril, bioinsecticidas, como pesticidas microbianos y otros entomopatógenos, protectores de plantas incorporados y pesticidas bioquímicos. La demanda de técnicas relacionadas al control biológico de insectos plaga en México deberá abordar los problemas de plagas transfronterizas, exóticas, de nueva introducción y las que se han mantenido por varias décadas en el país

The aim of this research was to evaluate the effect of mepiquat chloride applied at three times and three different doses: in the development, yield and quality of the cultivation of “escabeche” chili pepper (Capsicum baccatumvar. pendulum). In this experiment, a 23 factorial arrangement was used in a randomized complete block statistical design (DBCA) with four replications, the analysis of variance (ANVA) and the Duncan comparison test of means at 5% for the factors and levels were performed. The doses and moments evaluated were: mepiquat chloride at d1: 250; d2: 375 and d3: 500 ppm; application times at m1: 20, m2: 35 and m3: 50 days after transplanting. No statistically significant differences were found for the interaction of the dose x moment factor, nor for the moment factor. However, statistically significant differences were found for the dose factor and its levels in the variables yield and number of fruits per plant, obtaining the highest value in these variables at the doses of 250 and 375 ppm ofmepiquat chloride with a yield of 21,16 –21,07 t ha-1and 23,24 –22,94 fruits plant-1respectively, regardless of the time of application. Therefore, we can say that the application of mepiquat chloride at doses of 250 and 375 ppm had a positive effect on the crop, increasing the yield and number of fruits per plant, regardless of the time of application., El objetivo del presente trabajo fue evaluar el efecto del cloruro de mepiquat aplicado a tres momentos y tres dosis distintas; en el desarrollo, rendimiento y calidad del cultivo de ají escabeche (Capsicum baccatum var. pendulum). En este experimento se utilizó un arreglo factorial de 23 en un diseño estadístico de bloques completos al azar (DBCA) con cuatro repeticiones, se realizó el análisis de varianza (ANVA) y prueba de comparación de medias de Duncan al 5% para los factores y niveles empleados. Las dosis y momentos evaluados fueron: cloruro de mepiquat a d1: 250; d2: 375 y d3: 500 ppm; momentos de aplicación a m1: 20, m2: 35 y m3: 50 días después del trasplante. No se hallaron diferencias estadísticamente significativas para la interacción del factor dosis x momento, tampoco para el factor momento. Se encontraron diferencias estadísticamente significativas para el factor dosis y sus niveles en las variables rendimiento y número de frutos por planta, obteniéndose el mayor valor en dichas variables a las dosis de 250 y 375 ppm de cloruro de mepiquat con un rendimiento de 21,16 – 21,07 t ha-1 y 23,24 – 22,94 frutos planta-1 respectivamente, independientemente del momento de aplicación. Por lo tanto, podemos decir que la aplicación de cloruro de mepiquat a dosis de 250 y 375 ppm tuvo un efecto positivo en el cultivo incrementando el rendimiento y numero de frutos por planta, sin considerar el momento de aplicación.

The aim of this research was to evaluate the effect of mepiquat chloride applied at three times and three different doses: in the development, yield and quality of the cultivation of “escabeche” chili pepper (Capsicum baccatumvar. pendulum). In this experiment, a 23 factorial arrangement was used in a randomized complete block statistical design (DBCA) with four replications, the analysis of variance (ANVA) and the Duncan comparison test of means at 5% for the factors and levels were performed. The doses and moments evaluated were: mepiquat chloride at d1: 250; d2: 375 and d3: 500 ppm; application times at m1: 20, m2: 35 and m3: 50 days after transplanting. No statistically significant differences were found for the interaction of the dose x moment factor, nor for the moment factor. However, statistically significant differences were found for the dose factor and its levels in the variables yield and number of fruits per plant, obtaining the highest value in these variables at the doses of 250 and 375 ppm ofmepiquat chloride with a yield of 21,16 –21,07 t ha-1and 23,24 –22,94 fruits plant-1respectively, regardless of the time of application. Therefore, we can say that the application of mepiquat chloride at doses of 250 and 375 ppm had a positive effect on the crop, increasing the yield and number of fruits per plant, regardless of the time of application., El objetivo del presente trabajo fue evaluar el efecto del cloruro de mepiquat aplicado a tres momentos y tres dosis distintas; en el desarrollo, rendimiento y calidad del cultivo de ají escabeche (Capsicum baccatum var. pendulum). En este experimento se utilizó un arreglo factorial de 23 en un diseño estadístico de bloques completos al azar (DBCA) con cuatro repeticiones, se realizó el análisis de varianza (ANVA) y prueba de comparación de medias de Duncan al 5% para los factores y niveles empleados. Las dosis y momentos evaluados fueron: cloruro de mepiquat a d1: 250; d2: 375 y d3: 500 ppm; momentos de aplicación a m1: 20, m2: 35 y m3: 50 días después del trasplante. No se hallaron diferencias estadísticamente significativas para la interacción del factor dosis x momento, tampoco para el factor momento. Se encontraron diferencias estadísticamente significativas para el factor dosis y sus niveles en las variables rendimiento y número de frutos por planta, obteniéndose el mayor valor en dichas variables a las dosis de 250 y 375 ppm de cloruro de mepiquat con un rendimiento de 21,16 – 21,07 t ha-1 y 23,24 – 22,94 frutos planta-1 respectivamente, independientemente del momento de aplicación. Por lo tanto, podemos decir que la aplicación de cloruro de mepiquat a dosis de 250 y 375 ppm tuvo un efecto positivo en el cultivo incrementando el rendimiento y numero de frutos por planta, sin considerar el momento de aplicación.

The aim of this research was to evaluate the effect of mepiquat chloride applied at three times and three different doses: in the development, yield and quality of the cultivation of “escabeche” chili pepper (Capsicum baccatumvar. pendulum). In this experiment, a 23 factorial arrangement was used in a randomized complete block statistical design (DBCA) with four replications, the analysis of variance (ANVA) and the Duncan comparison test of means at 5% for the factors and levels were performed. The doses and moments evaluated were: mepiquat chloride at d1: 250; d2: 375 and d3: 500 ppm; application times at m1: 20, m2: 35 and m3: 50 days after transplanting. No statistically significant differences were found for the interaction of the dose x moment factor, nor for the moment factor. However, statistically significant differences were found for the dose factor and its levels in the variables yield and number of fruits per plant, obtaining the highest value in these variables at the doses of 250 and 375 ppm ofmepiquat chloride with a yield of 21,16 –21,07 t ha-1and 23,24 –22,94 fruits plant-1respectively, regardless of the time of application. Therefore, we can say that the application of mepiquat chloride at doses of 250 and 375 ppm had a positive effect on the crop, increasing the yield and number of fruits per plant, regardless of the time of application., El objetivo del presente trabajo fue evaluar el efecto del cloruro de mepiquat aplicado a tres momentos y tres dosis distintas; en el desarrollo, rendimiento y calidad del cultivo de ají escabeche (Capsicum baccatum var. pendulum). En este experimento se utilizó un arreglo factorial de 23 en un diseño estadístico de bloques completos al azar (DBCA) con cuatro repeticiones, se realizó el análisis de varianza (ANVA) y prueba de comparación de medias de Duncan al 5% para los factores y niveles empleados. Las dosis y momentos evaluados fueron: cloruro de mepiquat a d1: 250; d2: 375 y d3: 500 ppm; momentos de aplicación a m1: 20, m2: 35 y m3: 50 días después del trasplante. No se hallaron diferencias estadísticamente significativas para la interacción del factor dosis x momento, tampoco para el factor momento. Se encontraron diferencias estadísticamente significativas para el factor dosis y sus niveles en las variables rendimiento y número de frutos por planta, obteniéndose el mayor valor en dichas variables a las dosis de 250 y 375 ppm de cloruro de mepiquat con un rendimiento de 21,16 – 21,07 t ha-1 y 23,24 – 22,94 frutos planta-1 respectivamente, independientemente del momento de aplicación. Por lo tanto, podemos decir que la aplicación de cloruro de mepiquat a dosis de 250 y 375 ppm tuvo un efecto positivo en el cultivo incrementando el rendimiento y numero de frutos por planta, sin considerar el momento de aplicación.

[EN] Melon (Cucumis melo L.) is a crop with important agronomic interest worldwide. Because of the increase of drought and salinity in many cultivation areas as a result of anthropogenic global warming, the obtention of varieties tolerant to these conditions is a major objective for agronomical improvement. The identification of the limiting factors for stress tolerance could help to define the objectives and the traits which could be improved by classical breeding or other techniques. With this objective, we have characterized, at the physiological and biochemical levels, two different cultivars (sensitive or tolerant) of two different melon varieties (Galia and Piel de Sapo) under controlled drought or salt stress. We have performed physiological measurements, a complete amino acid profile and we have determined the sodium, potassium and hormone concentrations. This has allowed us to determine that the distinctive general trait for salt tolerance in melon are the levels of phenylalanine, histidine, proline and the Na+/K+ ratio, while the distinctive traits for drought tolerance are the hydric potential, isoleucine, glycine, phenylalanine, tryptophan, serine, and asparagine. These could be useful markers for breeding strategies or to predict which varieties are likely perform better under drought or salt stress. Our study has also allowed us to identify which metabolites and physiological traits are differentially regulated upon salt and drought stress between different varieties.

Melon (Cucumis melo L.) is a crop with important agronomic interest worldwide. Because of the increase of drought and salinity in many cultivation areas as a result of anthropogenic global warming, the obtention of varieties tolerant to these conditions is a major objective for agronomical improvement. The identification of the limiting factors for stress tolerance could help to define the objectives and the traits which could be improved by classical breeding or other techniques. With this objective, we have characterized, at the physiological and biochemical levels, two different cultivars (sensitive or tolerant) of two different melon varieties (Galia and Piel de Sapo) under controlled drought or salt stress. We have performed physiological measurements, a complete amino acid profile and we have determined the sodium, potassium and hormone concentrations. This has allowed us to determine that the distinctive general trait for salt tolerance in melon are the levels of phenylalanine, histidine, proline and the Na+/K+ ratio, while the distinctive traits for drought tolerance are the hydric potential, isoleucine, glycine, phenylalanine, tryptophan, serine, and asparagine. These could be useful markers for breeding strategies or to predict which varieties are likely perform better under drought or salt stress. Our study has also allowed us to identify which metabolites and physiological traits are differentially regulated upon salt and drought stress between different varieties.

Spring frosts exacerbated by global climate change have become a constant threat to temperate fruit production. Delaying the bloom date by plant growth regulators (PGRs) has been proposed as a practical frost avoidance strategy. Ethephon is an ethylene-releasing PGR found to delay bloom in several fruit species, yet its use is often coupled with harmful effects, limiting its applicability in commercial tree fruit production. Little information is available regarding the mechanisms by which ethephon influences blooming and bud dormancy. This study investigated the effects of fall-applied ethephon on bud phenology, cold hardiness, and hormonal balance throughout the bud dormancy cycle in peach. Our findings concluded that ethephon could alter several significant aspects of peach bud physiology, including accelerated leaf fall, extended chilling accumulation period, increased heat requirements, improved cold hardiness, and delayed bloom date. Ethephon effects on these traits were primarily dependent on its concentration and application timing, with a high concentration (500 ppm) and an early application timing (10% leaf fall) being the most effective. Endogenous ethylene levels were induced significantly in the buds when ethephon was applied at 10% versus 90% leaf fall, indicating that leaves are essential for ethephon uptake. The hormonal analysis of buds at regular intervals of chilling hours (CH) and growing degree hours (GDH) also indicated that ethephon might exert its effects through an abscisic acid (ABA)-independent way in dormant buds. Instead, our data signifies the role of jasmonic acid (JA) in mediating budburst and bloom in peach, which also appears to be influenced by ethephon treatment. Overall, this research presents a new perspective in interpreting horticultural traits in the light of biochemical and molecular data and sheds light on the potential role of JA in bud dormancy, which deserves further attention in future studies that aim at mitigating spr

En esta tesis doctoral se estudia el modo de vida tritrófico del hongo nematófago Pochonia chlamydosporia utilizando técnicas "multiómicas". Pochonia chlamydosporia (= Metacordyceps chlamydosporia) (Goddard) Zare y Gams es un hongo nematófago usado para el control de nematodos agalladores de la raíz (Meloidogyne spp.) (Forghani and Hajihassani, 2020), entre otros. P. chlamydosporia se distribuye por todo el mundo y tiene un modo de vida tritrófico, pudiendo también adoptar estilos de vida endófito y saprófito. El mecanismo que utiliza P. clamydosporia para infectar huevos de nematodo comprende la desacetilación de la quitina de su pared celular a quitosano para facilitar su degradación por quitosanasas (Aranda-Martinez et al., 2016). El quitosano es un biopolímero derivado de la quitina que también se encuentra en el exoesqueleto de artrópodos y crustáceos. El genoma de P. chlamydosporia codifica un elevado número de quitosanasas, gracias a las cuales es resistente a quitosano y puede utilizarlo como fuente de nutrientes (Palma-Guerrero et al., 2010). Ambos pueden combinarse para el control de plagas. En este trabajo de tesis doctoral se pretende estudiar mediante metabolómica, transcriptómica y genómica el modo de vida tritrófico de P. chlamydosporia añadiendo quitosano, para determinar los mecanismos de interacción del hongo en ese entorno. En último término, se pretende sentar las bases para desarrollar un sistema para reducir plagas y enfermedades de forma sostenible.

Broccoli is a cruciferous crop rich in health-promoting metabolites. Due to several factors, including anthropogenic global warming, aridity is increasing in many cultivation areas. There is a great demand to characterize the drought response of broccoli and use this knowledge to develop new cultivars able to maintain yield under water constraints. The aim of this study is to characterize the drought response at the physiological and molecular level of different broccoli (Brassica oleracea L. var. Italica Plenck) cultivars, previously characterized as drought-sensitive or drought-tolerant. This approach aims to identify different traits, which can constitute limiting factors for drought stress tolerance in broccoli. For this purpose, we have compared several physiological parameters and the complete profiles of amino acids, primary metabolites, hormones, and ions of drought-tolerant and drought-sensitive cultivars under stress and control conditions. We have found that drought-tolerant cultivars presented higher levels of methionine and abscisic acid and lower amounts of urea, quinic acid, and the gluconic acid lactone. Interestingly, we have also found that a drought treatment increases the levels of most essential amino acids in leaves and in florets. Our results have established physiological and molecular traits useful as distinctive markers to predict drought tolerance in broccoli or which could be reliably used for breeding new cultivars adapted to water scarcity. We have also found that a drought treatment increases the content of essential amino acids in broccoli.

Overexpression of genes involved in coumarin production and secretion can mitigate mycorrhizal incompatibility in nonhost Arabidopsis plants. The coumarin scopoletin, in particular, stimulates pre-penetration development and metabolism in mycorrhizal fungi. Although most plants can benefit from mutualistic associations with arbuscular mycorrhizal (AM) fungi, nonhost plant species such as the model Arabidopsis thaliana have acquired incompatibility. The transcriptional response of Arabidopsis to colonization by host-supported AM fungi switches from initial AM recognition to defense activation and plant growth antagonism. However, detailed functional information on incompatibility in nonhost-AM fungus interactions is largely missing. We studied interactions between host-sustained AM fungal networks of Rhizophagus irregularis and 18 Arabidopsis genotypes affected in nonhost penetration resistance, coumarin production and secretion, and defense (salicylic acid, jasmonic acid, and ethylene) and growth hormones (auxin, brassinosteroid, cytokinin, and gibberellin). We demonstrated that root-secreted coumarins can mitigate incompatibility by stimulating fungal metabolism and promoting initial steps of AM colonization. Moreover, we provide evidence that major molecular defenses in Arabidopsis do not operate as primary mechanisms of AM incompatibility nor of growth antagonism. Our study reveals that, although incompatible, nonhost plants can harbor hidden tools that promote initial steps of AM colonization. Moreover, it uncovered the coumarin scopoletin as a novel signal in the pre-penetration dialogue, with possible implications for the chemical communication in plant-mycorrhizal fungi associations.

Spring frosts exacerbated by global climate change have become a constant threat to temperate fruit production. Delaying the bloom date by plant growth regulators (PGRs) has been proposed as a practical frost avoidance strategy. Ethephon is an ethylene-releasing PGR found to delay bloom in several fruit species, yet its use is often coupled with harmful effects, limiting its applicability in commercial tree fruit production. Little information is available regarding the mechanisms by which ethephon influences blooming and bud dormancy. This study investigated the effects of fall-applied ethephon on bud phenology, cold hardiness, and hormonal balance throughout the bud dormancy cycle in peach. Our findings concluded that ethephon could alter several significant aspects of peach bud physiology, including accelerated leaf fall, extended chilling accumulation period, increased heat requirements, improved cold hardiness, and delayed bloom date. Ethephon effects on these traits were primarily dependent on its concentration and application timing, with a high concentration (500 ppm) and an early application timing (10% leaf fall) being the most effective. Endogenous ethylene levels were induced significantly in the buds when ethephon was applied at 10% versus 90% leaf fall, indicating that leaves are essential for ethephon uptake. The hormonal analysis of buds at regular intervals of chilling hours (CH) and growing degree hours (GDH) also indicated that ethephon might exert its effects through an abscisic acid (ABA)-independent way in dormant buds. Instead, our data signifies the role of jasmonic acid (JA) in mediating budburst and bloom in peach, which also appears to be influenced by ethephon treatment. Overall, this research presents a new perspective in interpreting horticultural traits in the light of biochemical and molecular data and sheds light on the potential role of JA in bud dormancy, which deserves further attention in future studies that aim at mitigating spr

Melon (Cucumis melo L.) is a crop with important agronomic interest worldwide. Because of the increase of drought and salinity in many cultivation areas as a result of anthropogenic global warming, the obtention of varieties tolerant to these conditions is a major objective for agronomical improvement. The identification of the limiting factors for stress tolerance could help to define the objectives and the traits which could be improved by classical breeding or other techniques. With this objective, we have characterized, at the physiological and biochemical levels, two different cultivars (sensitive or tolerant) of two different melon varieties (Galia and Piel de Sapo) under controlled drought or salt stress. We have performed physiological measurements, a complete amino acid profile and we have determined the sodium, potassium and hormone concentrations. This has allowed us to determine that the distinctive general trait for salt tolerance in melon are the levels of phenylalanine, histidine, proline and the Na+/K+ ratio, while the distinctive traits for drought tolerance are the hydric potential, isoleucine, glycine, phenylalanine, tryptophan, serine, and asparagine. These could be useful markers for breeding strategies or to predict which varieties are likely perform better under drought or salt stress. Our study has also allowed us to identify which metabolites and physiological traits are differentially regulated upon salt and drought stress between different varieties.

En esta tesis doctoral se estudia el modo de vida tritrófico del hongo nematófago Pochonia chlamydosporia utilizando técnicas "multiómicas". Pochonia chlamydosporia (= Metacordyceps chlamydosporia) (Goddard) Zare y Gams es un hongo nematófago usado para el control de nematodos agalladores de la raíz (Meloidogyne spp.) (Forghani and Hajihassani, 2020), entre otros. P. chlamydosporia se distribuye por todo el mundo y tiene un modo de vida tritrófico, pudiendo también adoptar estilos de vida endófito y saprófito. El mecanismo que utiliza P. clamydosporia para infectar huevos de nematodo comprende la desacetilación de la quitina de su pared celular a quitosano para facilitar su degradación por quitosanasas (Aranda-Martinez et al., 2016). El quitosano es un biopolímero derivado de la quitina que también se encuentra en el exoesqueleto de artrópodos y crustáceos. El genoma de P. chlamydosporia codifica un elevado número de quitosanasas, gracias a las cuales es resistente a quitosano y puede utilizarlo como fuente de nutrientes (Palma-Guerrero et al., 2010). Ambos pueden combinarse para el control de plagas. En este trabajo de tesis doctoral se pretende estudiar mediante metabolómica, transcriptómica y genómica el modo de vida tritrófico de P. chlamydosporia añadiendo quitosano, para determinar los mecanismos de interacción del hongo en ese entorno. En último término, se pretende sentar las bases para desarrollar un sistema para reducir plagas y enfermedades de forma sostenible.

Broccoli is a cruciferous crop rich in health-promoting metabolites. Due to several factors, including anthropogenic global warming, aridity is increasing in many cultivation areas. There is a great demand to characterize the drought response of broccoli and use this knowledge to develop new cultivars able to maintain yield under water constraints. The aim of this study is to characterize the drought response at the physiological and molecular level of different broccoli (Brassica oleracea L. var. Italica Plenck) cultivars, previously characterized as drought-sensitive or drought-tolerant. This approach aims to identify different traits, which can constitute limiting factors for drought stress tolerance in broccoli. For this purpose, we have compared several physiological parameters and the complete profiles of amino acids, primary metabolites, hormones, and ions of drought-tolerant and drought-sensitive cultivars under stress and control conditions. We have found that drought-tolerant cultivars presented higher levels of methionine and abscisic acid and lower amounts of urea, quinic acid, and the gluconic acid lactone. Interestingly, we have also found that a drought treatment increases the levels of most essential amino acids in leaves and in florets. Our results have established physiological and molecular traits useful as distinctive markers to predict drought tolerance in broccoli or which could be reliably used for breeding new cultivars adapted to water scarcity. We have also found that a drought treatment increases the content of essential amino acids in broccoli.

Spring frosts exacerbated by global climate change have become a constant threat to temperate fruit production. Delaying the bloom date by plant growth regulators (PGRs) has been proposed as a practical frost avoidance strategy. Ethephon is an ethylene-releasing PGR found to delay bloom in several fruit species, yet its use is often coupled with harmful effects, limiting its applicability in commercial tree fruit production. Little information is available regarding the mechanisms by which ethephon influences blooming and bud dormancy. This study investigated the effects of fall-applied ethephon on bud phenology, cold hardiness, and hormonal balance throughout the bud dormancy cycle in peach. Our findings concluded that ethephon could alter several significant aspects of peach bud physiology, including accelerated leaf fall, extended chilling accumulation period, increased heat requirements, improved cold hardiness, and delayed bloom date. Ethephon effects on these traits were primarily dependent on its concentration and application timing, with a high concentration (500 ppm) and an early application timing (10% leaf fall) being the most effective. Endogenous ethylene levels were induced significantly in the buds when ethephon was applied at 10% versus 90% leaf fall, indicating that leaves are essential for ethephon uptake. The hormonal analysis of buds at regular intervals of chilling hours (CH) and growing degree hours (GDH) also indicated that ethephon might exert its effects through an abscisic acid (ABA)-independent way in dormant buds. Instead, our data signifies the role of jasmonic acid (JA) in mediating budburst and bloom in peach, which also appears to be influenced by ethephon treatment. Overall, this research presents a new perspective in interpreting horticultural traits in the light of biochemical and molecular data and sheds light on the potential role of JA in bud dormancy, which deserves further attention in future studies that aim at mitigating spr

This article describes my involvement in the development of genetics as an essential tool in the integrated study of plant biology. My research comes from a strong background in plant genetics based on my education as a plant breeder at Wageningen University and collaborations with plant physiologists and molecular geneticists in Wageningen and the wider scientific community. It initially involved the isolation and physiological characterization of mutants defective in biosynthesis or mode of action of plant hormones, photoreceptors and traits such as flowering time in both Arabidopsis and tomato. I also generated a genetic map of Arabidopsis. Subsequently, the exploitation of natural variation became a main area of interest, including the molecular identification of underlying genetic differences. The integration of various disciplines and the adoption of Arabidopsis as a main model species contributed strongly to the impressive progress in our knowledge of plant biology over the past 40 years.

In this work, we use electrophysiological and metabolomic tools to determine the role of chitosan as plant defense elicitor in soil for preventing or manage root pests and diseases sustainably. Root exudates include a wide variety of molecules that plants and root microbiota use to communicate in the rhizosphere. Tomato plants were treated with chitosan. Root exudates from tomato plants were analyzed at 3, 10, 20, and 30 days after planting (dap). We found, using high performance liquid chromatography (HPLC) and excitation emission matrix (EEM) fluorescence, that chitosan induces plant hormones, lipid signaling and defense compounds in tomato root exudates, including phenolics. High doses of chitosan induce membrane depolarization and affect membrane integrity. 1H-NMR showed the dynamic of exudation, detecting the largest number of signals in 20 dap root exudates. Root exudates from plants irrigated with chitosan inhibit ca. twofold growth kinetics of the tomato root parasitic fungus Fusarium oxysporum f. sp. radicis-lycopersici. and reduced ca. 1.5-fold egg hatching of the root-knot nematode Meloidogyne javanica.

In this work, we use electrophysiological and metabolomic tools to determine the role of chitosan as plant defense elicitor in soil for preventing or manage root pests and diseases sustainably. Root exudates include a wide variety of molecules that plants and root microbiota use to communicate in the rhizosphere. Tomato plants were treated with chitosan. Root exudates from tomato plants were analyzed at 3, 10, 20, and 30 days after planting (dap). We found, using high performance liquid chromatography (HPLC) and excitation emission matrix (EEM) fluorescence, that chitosan induces plant hormones, lipid signaling and defense compounds in tomato root exudates, including phenolics. High doses of chitosan induce membrane depolarization and affect membrane integrity. 1H-NMR showed the dynamic of exudation, detecting the largest number of signals in 20 dap root exudates. Root exudates from plants irrigated with chitosan inhibit ca. twofold growth kinetics of the tomato root parasitic fungus Fusarium oxysporum f. sp. radicis-lycopersici. and reduced ca. 1.5-fold egg hatching of the root-knot nematode Meloidogyne javanica.

Auxins are commonly used for commercial propagation of chrysanthemums by stem cuttings. Recent studies imply that these root-promoting hormones also affect plant defense responses. The underlying motive of this study stems from the serendipitous observation that water dipping of auxin-coated cuttings beneficially affected thrips herbivory. Therefore, the primary objective of this investigation was to explore the role of indole-3-butyric acid (IBA) in relation to herbivore susceptibility in chrysanthemum. We observed contrasting findings concerning the physical presence of IBA and it’s role in promoting susceptibility of cuttings to thrips, which may in part be explained by the phenotypical variations of cuttings generated from mother plants. Nonetheless, we repeatedly demonstrated considerable protection, in some experiments up to 37%, against thrips and leaf miner upon water dipping of IBA-coated cuttings. Assessment of polyphenol oxidase activity (PPO), 14 days after dipping treatment, suggests that neither direct induction nor priming of plant defenses are involved. Future experiments aimed at understanding the early signaling events may help to explain the underlying mechanisms involved in conferring herbivore protection. We propose a dual role for auxins in early integrated pest management strategies to maximize plant development and minimize herbivory through feasible, cost-effective water dipping treatments.

Plant hormones are signaling molecules that are localized in different plant tissues and in specific amounts according to the process that they regulate. Changes in the concentration and distribution of plant hormones modulate the development and responses to biotic and abiotic stress.Autophagy, which means self-digestion, is a mechanism that degrades damaged or toxic components that arise from the metabolism, in order to recycle them and maintain the health of the cell. The most studied type of autophagy is macroautophagy which will be referred in this review as autophagy. In this process, double membrane vesicles called autophagosomes are formed to enclose damaged or unwanted cell cargo, which is later deposited for its degradation into the vacuole, from where the cell recovers amino acids, lipids and proteins. Indeed, communication between plant hormones and autophagy has been observed during development and growth, senescence and programmed cell death.In this review we discuss the advances in the understanding of the role of plant hormones involved in the modulation of autophagy in plants., Las hormonas vegetales son moléculas señalizadoras que se localizan en los diferentes tejidos de una planta y en cantidades específicas de acuerdo al proceso que regulan. Los cambios en la concentración y distribución de las hormonas vegetales modulan el desarrollo y las respuestas al estrés biótico y abiótico.La autofagia, que significa autodigestión, es un mecanismo que degrada los componentes dañados o tóxicos que surgen del metabolismo, con la finalidad de reciclarlos y mantener la salud de la célula. En este proceso se forman vesículas de doble membrana llamadas autofagosomas, las cuales encierran la carga dañada o no deseada, que posteriormente se deposita para su degradación en la vacuola de donde la célula recupera aminoácidos, lípidos y proteínas. Se ha observado una confluencia entre las hormonas vegetales y la autofagia durante el desarrollo y el crecimiento, la senescencia y la muerte celular programada.En esta revisión repasamos los avances en la comprensión del papel de las hormonas vegetales involucradas en la modulación de la autofagia en las plantas.

Faced with a population in constant growth (with a forecast of 8.5 billion in 2030 according to the UN), as well as a global climate problem in the coming years, it is imperative to develop new technologies in the field of agriculture. Due to the important role of phytohormones in the growth and maturation of the plant, the use of different hormones such as auxins, gibberellins, ethylene or cytokinins is being researched. The use of gibberellins, phytohormones capable of promoting stem growth, number of inflorescences and resistance to saline stress, is presented as a tool with much potential in the agricultural world. However, current production methods, such as submerged fermentation of Gibberella fujikuroi, are under development, making it unfeasible for extensive use in crops. The use of Saccharomyces cerevisiae as a producer of gibberellins has been modelled in this final grade work. To carry out this task, bioinformatic tools have been used such as COBRApy, a package implemented in Python for the analysis of metabolic pathways of mathematical models using annotated genomes. The use of these tools allows to study in-silico the viability of gibberellin production in S. Cerevisiae. COBRApy allows simulations of metabolic pathways and different studies on the metabolism of the organism, which makes it ideal as an initial phase of a biotechnological project. Once the conditions of the environment have been established, with an input of 10mmol of glucose as the only source of carbon, the maximum production of biomass, gibberellins and the combination of both has been analysed. The maximum production of biomass and gibberellins when optimized separately has been 9.75% and 6.73% of the total carbon flow respectively. In order to improve the production of gibberellins, flow distribution comparison analysis describes a proposal of knockouts that could help redistribute the carbon flow. However, although the in-vivo results may differ, the model does not predict improvem

Plant hormones are signaling molecules that are localized in different plant tissues and in specific amounts according to the process that they regulate. Changes in the concentration and distribution of plant hormones modulate the development and responses to biotic and abiotic stress.Autophagy, which means self-digestion, is a mechanism that degrades damaged or toxic components that arise from the metabolism, in order to recycle them and maintain the health of the cell. The most studied type of autophagy is macroautophagy which will be referred in this review as autophagy. In this process, double membrane vesicles called autophagosomes are formed to enclose damaged or unwanted cell cargo, which is later deposited for its degradation into the vacuole, from where the cell recovers amino acids, lipids and proteins. Indeed, communication between plant hormones and autophagy has been observed during development and growth, senescence and programmed cell death.In this review we discuss the advances in the understanding of the role of plant hormones involved in the modulation of autophagy in plants., Las hormonas vegetales son moléculas señalizadoras que se localizan en los diferentes tejidos de una planta y en cantidades específicas de acuerdo al proceso que regulan. Los cambios en la concentración y distribución de las hormonas vegetales modulan el desarrollo y las respuestas al estrés biótico y abiótico.La autofagia, que significa autodigestión, es un mecanismo que degrada los componentes dañados o tóxicos que surgen del metabolismo, con la finalidad de reciclarlos y mantener la salud de la célula. En este proceso se forman vesículas de doble membrana llamadas autofagosomas, las cuales encierran la carga dañada o no deseada, que posteriormente se deposita para su degradación en la vacuola de donde la célula recupera aminoácidos, lípidos y proteínas. Se ha observado una confluencia entre las hormonas vegetales y la autofagia durante el desarrollo y el crecimiento, la senescencia y la muerte celular programada.En esta revisión repasamos los avances en la comprensión del papel de las hormonas vegetales involucradas en la modulación de la autofagia en las plantas.

Plant hormones are signaling molecules that are localized in different plant tissues and in specific amounts according to the process that they regulate. Changes in the concentration and distribution of plant hormones modulate the development and responses to biotic and abiotic stress.Autophagy, which means self-digestion, is a mechanism that degrades damaged or toxic components that arise from the metabolism, in order to recycle them and maintain the health of the cell. The most studied type of autophagy is macroautophagy which will be referred in this review as autophagy. In this process, double membrane vesicles called autophagosomes are formed to enclose damaged or unwanted cell cargo, which is later deposited for its degradation into the vacuole, from where the cell recovers amino acids, lipids and proteins. Indeed, communication between plant hormones and autophagy has been observed during development and growth, senescence and programmed cell death.In this review we discuss the advances in the understanding of the role of plant hormones involved in the modulation of autophagy in plants., Las hormonas vegetales son moléculas señalizadoras que se localizan en los diferentes tejidos de una planta y en cantidades específicas de acuerdo al proceso que regulan. Los cambios en la concentración y distribución de las hormonas vegetales modulan el desarrollo y las respuestas al estrés biótico y abiótico.La autofagia, que significa autodigestión, es un mecanismo que degrada los componentes dañados o tóxicos que surgen del metabolismo, con la finalidad de reciclarlos y mantener la salud de la célula. En este proceso se forman vesículas de doble membrana llamadas autofagosomas, las cuales encierran la carga dañada o no deseada, que posteriormente se deposita para su degradación en la vacuola de donde la célula recupera aminoácidos, lípidos y proteínas. Se ha observado una confluencia entre las hormonas vegetales y la autofagia durante el desarrollo y el crecimiento, la senescencia y la muerte celular programada.En esta revisión repasamos los avances en la comprensión del papel de las hormonas vegetales involucradas en la modulación de la autofagia en las plantas.

Plant hormone ethylene plays important roles in plant growth, development, and stress responses. Decades of molecular genetic work has established a central dogma for the major ethylene signaling pathway, in which the ethylene signal is perceived by a family of ethylene receptors located on the endoplasmic reticulum endomembrane systems and its signal is transduced down to the C-terminal domain dephohsphoryaltion of a positive ethylene response regulator, Ethylene Insensitive 2 (EIN2). This dephosphorylated C-terminal fragment of EIN2 protein migrates into the nucleus to activate and stabilize both Ethylene Insensitive 3 (EIN3) and Ethylene Insensitive 3-Like 1 (EIL1) transcription factors and to further regulate the expression of a large set of downstream Ethylene Response Factors (ERFs), which leads to diverse ethylene responses. However, the emerging functional phosphoproteomic and molecular genetic studies have also demonstrated that there exist alternative ethylene signaling pathways independent to EIN3 and EIL1. Protein acetylation is one of post-translational modifications (PTMs) and involved in many biological and cellular processes. To identify novel acetylation sites and monitor ethylene-induced dynamic acetylome changes, we have developed a dimethyl-labelling-based extracted ion chromatogram (XIC) workflow of quantitative PTM proteomics and applied it on Arabidopsis ein3/eil1 double mutant. The workflow comprised 4-component (4C) steps: c̲hemical labelling (i.e., dimethyl labelling), c̲hromatographic enrichment, c̲omputational analysis (i.e., identification and quantification), and c̲onfirmation of identified PTM sites (i.e., immunoblot analysis). Ultimately, 5,250 acetylation sites on 2,638 acetylproteins were repeatedly identified. Among them, 4,228 acetylation sites (i.e., 80.5%) were newly discovered. As a result, we have substantially expanded the database of Arabidopsis acetylation sites from 3,122 sites to 7,350 sites. Previous study showed that ac

Plant hormone ethylene plays important roles in plant growth, development, and stress responses. Decades of molecular genetic work has established a central dogma for the major ethylene signaling pathway, in which the ethylene signal is perceived by a family of ethylene receptors located on the endoplasmic reticulum endomembrane systems and its signal is transduced down to the C-terminal domain dephohsphoryaltion of a positive ethylene response regulator, Ethylene Insensitive 2 (EIN2). This dephosphorylated C-terminal fragment of EIN2 protein migrates into the nucleus to activate and stabilize both Ethylene Insensitive 3 (EIN3) and Ethylene Insensitive 3-Like 1 (EIL1) transcription factors and to further regulate the expression of a large set of downstream Ethylene Response Factors (ERFs), which leads to diverse ethylene responses. However, the emerging functional phosphoproteomic and molecular genetic studies have also demonstrated that there exist alternative ethylene signaling pathways independent to EIN3 and EIL1. Protein acetylation is one of post-translational modifications (PTMs) and involved in many biological and cellular processes. To identify novel acetylation sites and monitor ethylene-induced dynamic acetylome changes, we have developed a dimethyl-labelling-based extracted ion chromatogram (XIC) workflow of quantitative PTM proteomics and applied it on Arabidopsis ein3/eil1 double mutant. The workflow comprised 4-component (4C) steps: c̲hemical labelling (i.e., dimethyl labelling), c̲hromatographic enrichment, c̲omputational analysis (i.e., identification and quantification), and c̲onfirmation of identified PTM sites (i.e., immunoblot analysis). Ultimately, 5,250 acetylation sites on 2,638 acetylproteins were repeatedly identified. Among them, 4,228 acetylation sites (i.e., 80.5%) were newly discovered. As a result, we have substantially expanded the database of Arabidopsis acetylation sites from 3,122 sites to 7,350 sites. Previous study showed that ac

Background:The production of a new lateral root from parental root primary tissues has been investigated extensively, and the most important regulatory mechanisms are now well known. A first regulatory mechanism is based on the synthesis of small peptides which interact ectopically with membrane receptors to elicit a modulation of transcription factor target genes. A second mechanism involves a complex cross-talk between plant hormones. It is known that lateral roots are formed even in parental root portions characterized by the presence of secondary tissues, but there is not yet agreement about the putative tissue source providing the cells competent to become founder cells of a new root primordium. Scope:We suggest models of possible regulatory mechanisms for inducing specific root vascular cambium (VC) stem cells to abandon their activity in the production of xylem and phloem elements and to start instead the construction of a new lateral root primordium. Considering the ontogenic nature of the VC, the models which we suggest are the result of a comparative review of mechanisms known to control the activity of stem cells in the root apical meristem, procambium and VC. Stem cells in the root meristems can inherit various competences to play different roles, and their fate could be decided in response to cross-talk between endogenous and exogenous signals. Conclusions:We have found a high degree of relatedness among the regulatory mechanisms controlling the various root meristems. This fact suggests that competence to form new lateral roots can be inherited by some stem cells of the VC lineage. This kind of competence could be represented by a sensitivity of specific stem cells to factors such as those presented in our models.

Plant hormone ethylene plays important roles in plant growth, development, and stress responses. Decades of molecular genetic work has established a central dogma for the major ethylene signaling pathway, in which the ethylene signal is perceived by a family of ethylene receptors located on the endoplasmic reticulum endomembrane systems and its signal is transduced down to the C-terminal domain dephohsphoryaltion of a positive ethylene response regulator, Ethylene Insensitive 2 (EIN2). This dephosphorylated C-terminal fragment of EIN2 protein migrates into the nucleus to activate and stabilize both Ethylene Insensitive 3 (EIN3) and Ethylene Insensitive 3-Like 1 (EIL1) transcription factors and to further regulate the expression of a large set of downstream Ethylene Response Factors (ERFs), which leads to diverse ethylene responses. However, the emerging functional phosphoproteomic and molecular genetic studies have also demonstrated that there exist alternative ethylene signaling pathways independent to EIN3 and EIL1. Protein acetylation is one of post-translational modifications (PTMs) and involved in many biological and cellular processes. To identify novel acetylation sites and monitor ethylene-induced dynamic acetylome changes, we have developed a dimethyl-labelling-based extracted ion chromatogram (XIC) workflow of quantitative PTM proteomics and applied it on Arabidopsis ein3/eil1 double mutant. The workflow comprised 4-component (4C) steps: c̲hemical labelling (i.e., dimethyl labelling), c̲hromatographic enrichment, c̲omputational analysis (i.e., identification and quantification), and c̲onfirmation of identified PTM sites (i.e., immunoblot analysis). Ultimately, 5,250 acetylation sites on 2,638 acetylproteins were repeatedly identified. Among them, 4,228 acetylation sites (i.e., 80.5%) were newly discovered. As a result, we have substantially expanded the database of Arabidopsis acetylation sites from 3,122 sites to 7,350 sites. Previous study showed that ac

Plants possess various inducible defences that result in synthesis of specialized metabolites in response to herbivory, which can interfere with the performance of herbivores of the same and other species. Much less is known of the effects of plant feeding by omnivores. We found that previous feeding of the omnivorous predator Macrolophus pygmaeus on sweet pepper plants significantly reduced reproduction of the two-spotted spider mite Tetranychus urticae and western flower thrips Frankliniella occidentalis on the same plants, also on leaves that had not been exposed to the omnivore. In contrast, no effect was found on the reproduction of the green peach aphid Myzus persicae. Juvenile survival and developmental time of T. urticae and M. persicae, and larval survival of F. occidentalis were not affected by plant feeding by M. pygmaeus. Larvae of F. occidentalis feeding on leaves previously exposed to M. pygmaeus required longer to develop into adults. Defence-related plant hormones were produced locally and systemically after exposure to M. pygmaeus. The concentrations of 12-oxo-phytodienoic acid and jasmonic acid–isoleucine in the attacked leaves were significantly higher than in the corresponding leaves on the uninfested plants, and jasmonic acid concentrations showed the same trend, suggesting that jasmonic-acid-related defence pathways were activated. In contrast, similar concentrations of salicylic acid were found in the attacked leaves of M. pygmaeus-infested plants and uninfested plants. Our results show that plant feeding by omnivorous predators decreases the performance of herbivores, suggesting that it induces plant defences.

Parallel adaptations enabling the use of plant cells as the primary food source have occurred multiple times in distinct nematode clades. The hallmark of all extant obligate and facultative plant-feeding nematodes is the presence of an oral stylet, which is required for penetration of plant cell walls, delivery of pharyngeal gland secretions into host cells and selective uptake of plant assimilates. Plant parasites from different clades, and even within a single clade, display a large diversity in feeding behaviours ranging from short feeding cycles on single cells to prolonged feeding on highly sophisticated host cell complexes. Despite these differences, feeding of nematodes frequently (but certainly not always) induces common responses in host cells (e.g. endopolyploidization and cellular hypertrophy). It is thought that these host cell responses are brought about by the interplay of effectors and other biological active compounds in stylet secretions of feeding nematodes, but this has only been studied for the most advanced sedentary plant parasites. In fact, these responses are thought to be fundamental for prolonged feeding of sedentary plant parasites on host cells. However, as we discuss in this review, some of these common plant responses to independent lineages of plant parasitic nematodes might also be generic reactions to cell stress and as such their onset may not require specific inputs from plant parasitic nematodes. Sedentary plant parasitic nematodes may utilize effectors and their ability to synthesize other biologically active compounds to tailor these common responses for prolonged feeding on host cells.

Living organisms are part of a highly interconnected web of interactions, characterised by species nurturing, competing, parasitizing and preying on one another. Plants have evolved cooperative as well as defensive strategies to interact with neighbour organisms. Among these, the plant-fungus associations are very diverse, ranging from pathogenic to mutualistic. Our current knowledge of plant-fungus interactions suggests a sophisticated coevolution to ensure dynamic plant responses to evolving fungal mutualistic/pathogenic strategies. The plant-fungus communication relies on a rich chemical language. To manipulate the plant defence mechanisms, fungi produce and secrete several classes of biomolecules, whose modeof-action is largely unknown. Upon perception of the fungi, plants produce phytohormones and a battery of secondary metabolites that serve as defence mechanism against invaders or to promote mutualistic associations. These mutualistic chemical signals can be co-opted by pathogenic fungi for their own benefit. Among the plant molecules regulating plant-fungus interaction, phytohormones play a critical role since they modulate various aspects of plant development, defences and stress responses. Intriguingly, fungi can also produce phytohormones, although the actual role of fungalproduced phytohormones in plant-fungus interactions is poorly understood. Here, we discuss the recent advances in fungal production of phytohormone, their putative role as endogenous fungal signals and how fungi manipulate plant hormone balance to their benefits.

Показано вплив кількості поліфенольних сполук у різних сортах хмелю на якість охмеленого сусла і готового пива в порівнянні з дією екстрактів, що не містять поліфенолів., The paper considers the effects of polyphenol compound quantities in various hop varieties on the quality of hopped wort and finished beer in comparison with the effect of extracts containing no polyphenols., Показано влияние количества полифенольных соединений в различных сортах хмеля на качество охмеленного сусла и готового пива в сравнении с действием экстрактов, которые не содержат полифенолов.

Показано вплив кількості поліфенольних сполук у різних сортах хмелю на якість охмеленого сусла і готового пива в порівнянні з дією екстрактів, що не містять поліфенолів., The paper considers the effects of polyphenol compound quantities in various hop varieties on the quality of hopped wort and finished beer in comparison with the effect of extracts containing no polyphenols., Показано влияние количества полифенольных соединений в различных сортах хмеля на качество охмеленного сусла и готового пива в сравнении с действием экстрактов, которые не содержат полифенолов.

Показано вплив кількості поліфенольних сполук у різних сортах хмелю на якість охмеленого сусла і готового пива в порівнянні з дією екстрактів, що не містять поліфенолів., The paper considers the effects of polyphenol compound quantities in various hop varieties on the quality of hopped wort and finished beer in comparison with the effect of extracts containing no polyphenols., Показано влияние количества полифенольных соединений в различных сортах хмеля на качество охмеленного сусла и готового пива в сравнении с действием экстрактов, которые не содержат полифенолов.

[EN] Seed longevity is the period during which the plant seed is able to germinate. This property is strongly influenced by environment conditions experienced by seeds during their formation and storage. In the present study we have analyzed how the biotic stress derived from the infection of Cauliflower mosaic virus (CaMV), Turnip mosaic virus (TuMV), Cucumber mosaic virus (CMV) and Alfalfa mosaic virus (AMV) affects seed tolerance to deterioration measuring germination rates after an accelerated aging treatment. Arabidopsis wild type plants infected with AMV and CMV rendered seeds with improved tolerance to deterioration when compared to the non -inoculated plants. On the other hand, CaMV infection generated seeds more sensitive to deterioration. No seeds were obtained from TuMV infected plants. Similar pattern of viral effects was observed in the double mutant athb22 athb25, which is more sensitive to accelerated seed aging than wild type. However, we observed a significant reduction of the seed germination for CMV (65% vs 55%) and healthy (50% vs 30%) plants in these mutants. The seed quality differences were overcomed using the A. thaliana athb25-1D dominant mutant, which over accumulated gibberellic acid (GA), except for TuMV which generated some siliques with low seed tolerance to deterioration. For AMV and TuMV (in athb25-1D), the seed quality correlated with the accumulation of the messengers of the gibberellin 3-oxidase family, the mucilage of the seed and the GA1. For CMV and CaMV it was not a good correlation suggesting that other factors are affecting seed viability. (C) 2017 Elsevier Masson SAS. All rights reserved.

It is of great importance to maintain the genetic diversity of traditional materials and wild plants. The Emilia applegermplasm was safeguarded, using in vitro tissue culture techniques. Two culture media and six concentrationswere evaluated for disinfection; in addition, eight treatments for budding, using different concentrations of6-benzylaminopurine (BAP) and for rooting four treatments with indole butyric acid (IBA). We used a DCA with a 2x 4 factorial arrangement with six observations. The percentages of contamination, oxidation, viability, days at sprouting,number of shoots and length of shoots were evaluated. Treatments equal to and greater than 10% NaClO for 10minutes had adequate values of non-contamination of explants. The lower number of oxidized explants had a directproportional correlation in the responses to less concentration and time of exposure. The highest percentage of viableexplants (77%) was expressed in 10% NaClO treatment for 15 minutes. The best responses regarding the variabledays to budding were presented in the treatments without BAP intervention. The best response in the number of outbreakswas manifested for the 1 ppm BAP treatment in the culture media (Murashige and Skoog modified - MSM andModified CHU 10 by Gerloff). The best response in the size of the outbreak was expressed in the treatment CHU + 1ppm BAP. The cellular tissues the Emilia apple show high susceptibility to microbial contaminants and the oxidationof tissues, which makes it difficult to multiply by in vitro culture. High concentrations of BAP inhibit spontaneousphysiological responses in explants of the Emilia apple, especially in the early stages where there is greater productionof intrinsic hormonal effects., Es de gran importancia mantener la diversidad genética de los materiales tradicionales y de plantas silvestres. Se realizóla salvaguarda del germoplasma de manzana Emilia, utilizando técnicas de cultivo de tejidos in vitro. Se evaluarondos medios de cultivo y seis concentraciones para desinfección; además, de ocho tratamientos para brotación, utilizandodistintas concentraciones de 6-bencilaminopurina (BAP) y para enraizamiento cuatro tratamientos con ácidoindol butírico (IBA). Se utilizó un DCA con un arreglo factorial 2 x 4 con seis observaciones. Se evaluó: porcentajes decontaminación, de oxidación, viabilidad, días a la brotación, numero de brotes y longitud de brotes. Los tratamientosiguales y superiores al 10% de NaClO durante 10 minutos presentaron valores adecuados de no contaminación deexplantes. La menor cantidad de explantes oxidados presentaron correlación directamente proporcional en las respuestasa menor concentración y tiempo de exposición. El mayor porcentaje de explantes viables (77%) se expresó enel tratamiento de NaClO al 10% durante 15 minutos. Las mejores respuestas en cuanto a la variable días a la brotaciónse presentó en los tratamientos sin intervención del BAP. La mejor respuesta en cuanto al número de brotes se manifestópara el tratamiento 1 ppm de BAP en los medios de cultivo (Murashige y Skoog modificado - MSM y MedioCHU 10 Modificado por Gerloff). La mejor respuesta en el tamaño del brote se expresó en el tratamiento CHU + 1 ppmde BAP. Los tejidos celulares de la manzana Emilia presentan alta susceptibilidad a contaminantes microbianos y a laoxidación de tejidos, por lo cual dificulta la multiplicación por medio de cultivo in vitro. Las altas concentraciones deBAP inhiben respuestas fisiológicas espontáneas en explantes de la manzana Emilia, especialmente en etapas inicialesdonde existe mayor producción de efectos hormonales intrínsecos.

It is of great importance to maintain the genetic diversity of traditional materials and wild plants. The Emilia applegermplasm was safeguarded, using in vitro tissue culture techniques. Two culture media and six concentrationswere evaluated for disinfection; in addition, eight treatments for budding, using different concentrations of6-benzylaminopurine (BAP) and for rooting four treatments with indole butyric acid (IBA). We used a DCA with a 2x 4 factorial arrangement with six observations. The percentages of contamination, oxidation, viability, days at sprouting,number of shoots and length of shoots were evaluated. Treatments equal to and greater than 10% NaClO for 10minutes had adequate values of non-contamination of explants. The lower number of oxidized explants had a directproportional correlation in the responses to less concentration and time of exposure. The highest percentage of viableexplants (77%) was expressed in 10% NaClO treatment for 15 minutes. The best responses regarding the variabledays to budding were presented in the treatments without BAP intervention. The best response in the number of outbreakswas manifested for the 1 ppm BAP treatment in the culture media (Murashige and Skoog modified - MSM andModified CHU 10 by Gerloff). The best response in the size of the outbreak was expressed in the treatment CHU + 1ppm BAP. The cellular tissues the Emilia apple show high susceptibility to microbial contaminants and the oxidationof tissues, which makes it difficult to multiply by in vitro culture. High concentrations of BAP inhibit spontaneousphysiological responses in explants of the Emilia apple, especially in the early stages where there is greater productionof intrinsic hormonal effects., Es de gran importancia mantener la diversidad genética de los materiales tradicionales y de plantas silvestres. Se realizóla salvaguarda del germoplasma de manzana Emilia, utilizando técnicas de cultivo de tejidos in vitro. Se evaluarondos medios de cultivo y seis concentraciones para desinfección; además, de ocho tratamientos para brotación, utilizandodistintas concentraciones de 6-bencilaminopurina (BAP) y para enraizamiento cuatro tratamientos con ácidoindol butírico (IBA). Se utilizó un DCA con un arreglo factorial 2 x 4 con seis observaciones. Se evaluó: porcentajes decontaminación, de oxidación, viabilidad, días a la brotación, numero de brotes y longitud de brotes. Los tratamientosiguales y superiores al 10% de NaClO durante 10 minutos presentaron valores adecuados de no contaminación deexplantes. La menor cantidad de explantes oxidados presentaron correlación directamente proporcional en las respuestasa menor concentración y tiempo de exposición. El mayor porcentaje de explantes viables (77%) se expresó enel tratamiento de NaClO al 10% durante 15 minutos. Las mejores respuestas en cuanto a la variable días a la brotaciónse presentó en los tratamientos sin intervención del BAP. La mejor respuesta en cuanto al número de brotes se manifestópara el tratamiento 1 ppm de BAP en los medios de cultivo (Murashige y Skoog modificado - MSM y MedioCHU 10 Modificado por Gerloff). La mejor respuesta en el tamaño del brote se expresó en el tratamiento CHU + 1 ppmde BAP. Los tejidos celulares de la manzana Emilia presentan alta susceptibilidad a contaminantes microbianos y a laoxidación de tejidos, por lo cual dificulta la multiplicación por medio de cultivo in vitro. Las altas concentraciones deBAP inhiben respuestas fisiológicas espontáneas en explantes de la manzana Emilia, especialmente en etapas inicialesdonde existe mayor producción de efectos hormonales intrínsecos.

[EN] Reproductive development in cotton, including the fruit and fiber formation, is a complex process; it involves the coordinated action of gene expression regulators, and it is highly influenced by plant hormones. Several studies have reported the identification and expression of the transcription factor family MADS-box members in cotton ovules and fibers; however, their roles are still elusive during the reproductive development in cotton. In this study, we evaluated the expression profiles of five MADS-box genes (GhMADS3, GhMADS4, GhMADS5, GhMADS6 and GhMADS7) belonging to the AGAMOUS-subfamily in Gossypium hirsutum. Phylogenetic and protein sequence analyses were performed using diploid (G. arboreum, G. raimondii) and tetraploid (G. barbadense, G. hirsutum) cotton genomes, as well as the AG-subfamily members from Arabidopsis thaliana, Petunia hybrida and Antirrhinum majus. qPCR analysis showed that the AG-subfamily genes had high expression during flower and fruit development in G. hirsutum. In situ hybridization analysis also substantiates the involvement of AG-subfamily members on reproductive tissues of G. hirsutum, including ovule and ovary. The effect of plant hormones on AG-subfamily genes expression was verified in cotton fruits treated with gibberellin, auxin and brassinosteroid. All the genes were significantly regulated in response to auxin, whereas only GhMADS3, GhMADS4 and GhMADS7 genes were also regulated by brassinosteroid treatment. In addition, we have investigated the GhMADS3 and GhMADS4 overexpression effects in Arabidopsis plants. Interestingly, the transgenic plants from both cotton AG-like genes in Arabidopsis significantly altered the fruit size compared to the control plants. This alteration suggests that cotton AG-like genes might act regulating fruit formation. Our results demonstrate that members of the AG-subfamily in G. hirsutum present a conserved expression profile during flower development, but also demonstrate their expression d

It is of great importance to maintain the genetic diversity of traditional materials and wild plants. The Emilia applegermplasm was safeguarded, using in vitro tissue culture techniques. Two culture media and six concentrationswere evaluated for disinfection; in addition, eight treatments for budding, using different concentrations of6-benzylaminopurine (BAP) and for rooting four treatments with indole butyric acid (IBA). We used a DCA with a 2x 4 factorial arrangement with six observations. The percentages of contamination, oxidation, viability, days at sprouting,number of shoots and length of shoots were evaluated. Treatments equal to and greater than 10% NaClO for 10minutes had adequate values of non-contamination of explants. The lower number of oxidized explants had a directproportional correlation in the responses to less concentration and time of exposure. The highest percentage of viableexplants (77%) was expressed in 10% NaClO treatment for 15 minutes. The best responses regarding the variabledays to budding were presented in the treatments without BAP intervention. The best response in the number of outbreakswas manifested for the 1 ppm BAP treatment in the culture media (Murashige and Skoog modified - MSM andModified CHU 10 by Gerloff). The best response in the size of the outbreak was expressed in the treatment CHU + 1ppm BAP. The cellular tissues the Emilia apple show high susceptibility to microbial contaminants and the oxidationof tissues, which makes it difficult to multiply by in vitro culture. High concentrations of BAP inhibit spontaneousphysiological responses in explants of the Emilia apple, especially in the early stages where there is greater productionof intrinsic hormonal effects., Es de gran importancia mantener la diversidad genética de los materiales tradicionales y de plantas silvestres. Se realizóla salvaguarda del germoplasma de manzana Emilia, utilizando técnicas de cultivo de tejidos in vitro. Se evaluarondos medios de cultivo y seis concentraciones para desinfección; además, de ocho tratamientos para brotación, utilizandodistintas concentraciones de 6-bencilaminopurina (BAP) y para enraizamiento cuatro tratamientos con ácidoindol butírico (IBA). Se utilizó un DCA con un arreglo factorial 2 x 4 con seis observaciones. Se evaluó: porcentajes decontaminación, de oxidación, viabilidad, días a la brotación, numero de brotes y longitud de brotes. Los tratamientosiguales y superiores al 10% de NaClO durante 10 minutos presentaron valores adecuados de no contaminación deexplantes. La menor cantidad de explantes oxidados presentaron correlación directamente proporcional en las respuestasa menor concentración y tiempo de exposición. El mayor porcentaje de explantes viables (77%) se expresó enel tratamiento de NaClO al 10% durante 15 minutos. Las mejores respuestas en cuanto a la variable días a la brotaciónse presentó en los tratamientos sin intervención del BAP. La mejor respuesta en cuanto al número de brotes se manifestópara el tratamiento 1 ppm de BAP en los medios de cultivo (Murashige y Skoog modificado - MSM y MedioCHU 10 Modificado por Gerloff). La mejor respuesta en el tamaño del brote se expresó en el tratamiento CHU + 1 ppmde BAP. Los tejidos celulares de la manzana Emilia presentan alta susceptibilidad a contaminantes microbianos y a laoxidación de tejidos, por lo cual dificulta la multiplicación por medio de cultivo in vitro. Las altas concentraciones deBAP inhiben respuestas fisiológicas espontáneas en explantes de la manzana Emilia, especialmente en etapas inicialesdonde existe mayor producción de efectos hormonales intrínsecos.

It is of great importance to maintain the genetic diversity of traditional materials and wild plants. The Emilia applegermplasm was safeguarded, using in vitro tissue culture techniques. Two culture media and six concentrationswere evaluated for disinfection; in addition, eight treatments for budding, using different concentrations of6-benzylaminopurine (BAP) and for rooting four treatments with indole butyric acid (IBA). We used a DCA with a 2x 4 factorial arrangement with six observations. The percentages of contamination, oxidation, viability, days at sprouting,number of shoots and length of shoots were evaluated. Treatments equal to and greater than 10% NaClO for 10minutes had adequate values of non-contamination of explants. The lower number of oxidized explants had a directproportional correlation in the responses to less concentration and time of exposure. The highest percentage of viableexplants (77%) was expressed in 10% NaClO treatment for 15 minutes. The best responses regarding the variabledays to budding were presented in the treatments without BAP intervention. The best response in the number of outbreakswas manifested for the 1 ppm BAP treatment in the culture media (Murashige and Skoog modified - MSM andModified CHU 10 by Gerloff). The best response in the size of the outbreak was expressed in the treatment CHU + 1ppm BAP. The cellular tissues the Emilia apple show high susceptibility to microbial contaminants and the oxidationof tissues, which makes it difficult to multiply by in vitro culture. High concentrations of BAP inhibit spontaneousphysiological responses in explants of the Emilia apple, especially in the early stages where there is greater productionof intrinsic hormonal effects., Es de gran importancia mantener la diversidad genética de los materiales tradicionales y de plantas silvestres. Se realizóla salvaguarda del germoplasma de manzana Emilia, utilizando técnicas de cultivo de tejidos in vitro. Se evaluarondos medios de cultivo y seis concentraciones para desinfección; además, de ocho tratamientos para brotación, utilizandodistintas concentraciones de 6-bencilaminopurina (BAP) y para enraizamiento cuatro tratamientos con ácidoindol butírico (IBA). Se utilizó un DCA con un arreglo factorial 2 x 4 con seis observaciones. Se evaluó: porcentajes decontaminación, de oxidación, viabilidad, días a la brotación, numero de brotes y longitud de brotes. Los tratamientosiguales y superiores al 10% de NaClO durante 10 minutos presentaron valores adecuados de no contaminación deexplantes. La menor cantidad de explantes oxidados presentaron correlación directamente proporcional en las respuestasa menor concentración y tiempo de exposición. El mayor porcentaje de explantes viables (77%) se expresó enel tratamiento de NaClO al 10% durante 15 minutos. Las mejores respuestas en cuanto a la variable días a la brotaciónse presentó en los tratamientos sin intervención del BAP. La mejor respuesta en cuanto al número de brotes se manifestópara el tratamiento 1 ppm de BAP en los medios de cultivo (Murashige y Skoog modificado - MSM y MedioCHU 10 Modificado por Gerloff). La mejor respuesta en el tamaño del brote se expresó en el tratamiento CHU + 1 ppmde BAP. Los tejidos celulares de la manzana Emilia presentan alta susceptibilidad a contaminantes microbianos y a laoxidación de tejidos, por lo cual dificulta la multiplicación por medio de cultivo in vitro. Las altas concentraciones deBAP inhiben respuestas fisiológicas espontáneas en explantes de la manzana Emilia, especialmente en etapas inicialesdonde existe mayor producción de efectos hormonales intrínsecos.

Proline accumulation occurs in plants following the exposure to a wide array of stress conditions, as well as during numerous physiological and adaptive processes. Increasing evidence also supports the involvement of proline metabolism in the plant response to pathogen attack. This requires that the biosynthetic pathway is triggered by components of numerous and different signal transduction chains. Indeed, several reports recently described activation of genes coding for enzymes of the glutamate pathway by transcription factors (TFs) belonging to various families. Here, we summarize some of these findings with special emphasis on rice, and show the occurrence of a plethora of putative TF binding sites in the promoter of such genes., info:eu-repo/semantics/published