Phytophthora capsici is a highly destructive pathogen of crops. Although chemical pesticides are the most widely used strategy to counter phytopathogens, they have been inefficient to combat P. ...capsici and have produced significant environmental and health problems. Therefore, sustainable alternatives to control soilborne pathogens, such as the inhibitory effect of self‐extracellular DNA (eDNA), have been proposed. This inhibition phenomenon has been attributed to the action of self‐eDNA as a damage‐associated molecular pattern (DAMP). Here, we describe the effect of self‐eDNA on P. capsici zoospore germination rate, antioxidant enzymes activity and MAPK gene expression. Also, the effect of P. capsici eDNA on the protection of chilli pepper (Capsicum annuum) plants against P. capsici was investigated. The results highlight that P. capsici can sense 2–500 µg/ml self‐eDNA and induce stress‐related responses like SAK1 gene expression, and superoxide dismutase and catalase activities. Moreover, in vitro zoospore germination rate was suppressed with self‐eDNA concentrations ranging from 50 to 500 µg/ml. Interestingly, drench applications of P. capsici eDNA at 60 and 100 µg/ml on chilli pepper plants did not show any protective effect against the phytopathogen, whereas 2 µg/ml of P. capsici eDNA drench application showed a lower percentage of plants with symptoms and lower disease severity. Moreover, phenols and total flavonoids were increased in chilli pepper plants, therefore inducing plant immunity. This study showed that self‐eDNA acts as a DAMP in P. capsici and provides insight into the use of eDNA for the protection of crops of agronomic interest.
This study showed that self‐eDNA acts as a DAMP in P. capsici inducing stress‐related responses, giving an insight into the use of self‐eDNA in field‐like conditions against the phytopathogen.
Chili pepper (
L.) production is affected by wilt and root rot, the most devastating disease caused by the pathogen complex of oomycete
Leon and the fungi
Schlecht and
Kühn, infecting roots, stems, ...leaves, and fruits. Fungicides are currently inefficient against this disease and have a high environmental impact. The use of elicitors is a sustainable alternative for inducing resistance to wilting and root rot. DNA fragments of an organism's own origin (conspecific or self-DNA) have shown the ability to inhibit growth and activate defense mechanisms in some plant species. In this investigation, the effect of the fragmented DNA mixture of
L.,
S., and
K. on the protection against wilt and root rot of
L. plants was evaluated. Changes in plant performance, phenolics, and flavonoids contents, as well as gene expression involved in the production of defense metabolites after the fragmented and unfragmented DNA mixture in three concentrations (20, 60, and 100 μg mL
) in chili peppers, were studied. The results obtained showed a decrease in plant height in 60 and 100 μg mL
concentrations in absence of pathogens. Moreover, the treatment with fragmented DNA 100 μg mL
showed significant increase in the content of phenolic compounds and total flavonoids as well as gene expression associated to plant defense in comparison with control plants. Interestingly, foliar application of DNA fragments of the pathogen complex to a concentration of 100 μg mL
caused a 40% decrease in the mortality of infected plants with the pathogens at 30 days post-inoculation compared with control plants inoculated with the pathogen complex but not sprayed with DNA fragments. These results suggested a perspective for application of fragmented DNA of these pathogens at the agricultural level in crop protection strategies to cope with wilt and root rot in
.
Agricultural systems face several challenges in terms of meeting everyday-growing quantities and qualities of food requirements. However, the ecological and social trade-offs for increasing ...agricultural production are high, therefore, more sustainable agricultural practices are desired. Researchers are currently working on diverse sustainable techniques based mostly on natural mechanisms that plants have developed along with their evolution. Here, we discuss the potential agricultural application of extracellular DNA (eDNA), its multiple functioning mechanisms in plant metabolism, the importance of hormetic curves establishment, and as a challenge: the technical limitations of the industrial scale for this technology. We highlight the more viable natural mechanisms in which eDNA affects plant metabolism, acting as a damage/microbe-associated molecular pattern (DAMP, MAMP) or as a general plant biostimulant. Finally, we suggest a whole sustainable system, where DNA is extracted from organic sources by a simple methodology to fulfill the molecular characteristics needed to be applied in crop production systems, allowing the reduction in, or perhaps the total removal of, chemical pesticides, fertilizers, and insecticides application.
As a recently explored agricultural practice, the controlled elicitation of plants offers high potential in multiple crop needs as growth promotion, activation of defenses and the production of ...specific metabolites. Extracellular DNA has been identified as a plant immune system elicitor but some aspects of the plant response have not been explored. In the present work, five DNA treatments were applied in tomato plants and the response of catalase, superoxide dismutase, phenylalanine ammonia lyase activities, hydrogen peroxide, total phenolics and flavonoid contents in leaves were spectrophotometrically measured. Treatments differed by the source and concentration of DNA and plant phenological stage of application. Furthermore, mathematical modeling and principal component analysis were performed to explore the behavior of each variable and their interaction. The most effective treatment was the self-DNA application in young plants based on the intensity and duration of immune system activation. The information given by the measured variables correlated positively with the phenylpropanoid pathway markers and negatively with catalase and superoxide dismutase activities. Results reported here propose an easy way to evaluate plant immune response activation by DNA and any other elicitor and provide useful information for future development of controlled elicitation strategies in crop production.
Se observaron plantas de abutilón (Abutilon x hybridum Hort. Ex. Voss. Malvacea) cultivadas en jardines públicos en el sur de la Ciudad de México, con una enfermedad de origen desconocido que induce ...síntomas de mosaico de color amarillo brillante, deformación y reducción de la lámina foliar, con pérdida severa de la coloración de las flores. Por la carencia de información sobre esta enfermedad en el abutilón y por el posible riesgo que representa para otras especies de plantas ornamentales en México, los objetivos fueron determinar la etiología y las características biológicas del patógeno asociado con el mosaico amarillo del abutilón. Se separó a un virus en plantas de abutilón con los síntomas descritos, que se transmitió experimentalmente por injerto, biobalística y por mosca blanca (Bemisia tabaci G.), pero no mecánicamente, a plantas indicadoras. La caracterización molecular demostró que éste virus era el Abutilon mosaic virus (AbMV), geminivirus perteneciente al género Begomovirus (Familia Geminiviridae). El análisis comparativo de las secuencias parciales de los componentes (Número de acceso AY311783) y B (Número de acceso AY311784) del AbMV de México con las disponibles en el Genebank, indicó una similitud de 92% con una variante del AbMV de Hawaii para el componente A y una similitud de 100% con el Sida yellow vein virus de Honduras para el componente B. El análisis comparativo de la secuencia de aminoácidos del gen de la proteína de la cápside permitió reconocer sólo dos mutaciones en el AbMV de México, de las cinco presentes en la variante de AbMV-Hawaii, relacionada con la no transmisión por mosca blanca de este geminivirus, lo que sugiere que el AbMV-México podría ser una variante del virus mosaico del abutilón no reportada previamente. Este parece ser el primer reporte de un geminivirus en abutilón en México.
Malacomeles denticulata es un fruto nativo de México al que recientemente se le ha encontrado características funcionales para proponerlo como una opción frutal. Esta investigación tuvo como objetivo ...elucidar la variabilidad de doce poblaciones de M. denticulata mediante marcadores Inter Secuencias Simples Repetidas o Intermicrosatélites (ISSR). Todos los ISSR presentaron altos valores en el Contenido de Información Polimórfica (PIC, por sus siglas en inglés) y el índice de diferenciación poblacional de Nei (GST), así como altos porcentajes de polimorfismo. Se crearon tres grupos de variabilidad, donde siete poblaciones de Guanajuato y la población del Tepozán, Querétaro, conformaron un grupo; mientras que las poblaciones de Agua Zarca (Guanajuato), La Joya (Querétaro) y Santa Catarina del Monte (México) conformaron otro. Finalmente, la población de San Miguel Tlaixpan (México) quedó separada como un grupo atípico. De acuerdo con el Análisis Molecular de Varianza (Amova), la variabilidad intrapoblacional representa el 47% y la interpoblacional el 53% de la variabilidad total, lo que concuerda con la variabilidad en caracteres de semilla, pero difiere a lo reportado para marcadores SSR.
Abstract
Circadian rhythms (CRs) are fundamental biological processes that significantly impact human well-being. Disruption of these rhythms can trigger insufficient neurocognitive development, ...insomnia, mental disorders, cardiovascular diseases, metabolic dysfunctions, and cancer. The field of chronobiology has increased our understanding of how rhythm disturbances contribute to cancer pathogenesis, and how circadian timing influences the efficacy of cancer treatments. As the circadian clock steadily gains recognition as an emerging factor in tumorigenesis, a thorough and comprehensive multi-omics analysis of CR genes/proteins has never been performed. To shed light on this, we performed, for the first time, an integrated data analysis encompassing genomic/transcriptomic alterations across 32 cancer types (n = 10,918 tumors) taken from the PanCancer Atlas, unfavorable prognostic protein analysis, protein–protein interactomics, and shortest distance score pathways to cancer hallmark phenotypes. This data mining strategy allowed us to unravel 31 essential CR-related proteins involved in the signaling crossroad between circadian rhythms and cancer. In the context of drugging the clock, we identified pharmacogenomic clinical annotations and drugs currently in late phase clinical trials that could be considered as potential cancer therapeutic strategies. These findings highlight the diverse roles of CR-related genes/proteins in the realm of cancer research and therapy.
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