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Ageratina pichinchensisis a medicinal plant, endemic to Mexico,known as Axihuitl. The extracts of the leaves show antifungal activity against dermatophyticfungi, but there are no studies of the identification of endophytic fungi. The objective was to identify endophytic fungi of A. pichinchensiswith potential as biological control agents of phytopathogens. Fifty-five morphospecies of endophytic fungi that belong to the phylum Ascomycotawere isolatedfrom the leaves of A. pichinchensis. Molecular identification based on the analysis of the sequences of internal transcribed spacers (ITSs) amplified by PCR showed that six of the most frequent fungi correspond to Remotididymella anthropophilaand Diaporthe caatingaensisand to the genera Diaporthe, Phomopsisand Fusarium.In multiple antagonism assays, seven morphospecies showed strong antagonistic activity against the pathogens Fusarium oxysporum, F. proliferatumand Stemphylium vesicarium. Two endophytic fungi belong to Alternaria alternata, another to Trichoderma longibrachiatumand two others are from the genera Alternariaand Phomopsis.While Nigrospora oryzaewas the only most frequent endophyte and with antagonistic activity against the three pathogens. In dual culture assays, endophytes with strong antagonistic activity inhibited the mycelial growth of F. oxysporumand F. proliferatumby 37 to 80%,but in the poisoned food assay, T. longibrachiatuminhibited the mycelial growth of the two pathogens by 79% and 66%, respectively. For the first time,R. anthropophilaas an endophytic fungus, as well as the identification and antagonistic activity of endophytic fungi of A. pichinchensis, are reported, Ageratina pichinchensis es una planta medicinal, endémica de México conocida como Axihuitl. Los extractos de las hojas muestran actividad antifúngica contra hongos dermatofitos, pero no hay estudios de la identificación de los hongos endófitos. El objetivo fue identificar hongos endófitos de A. pichinchensis con potencial como agentes de control biológico de fitopatógenos. De las hojas de A. pichinchensis se aislaron 55 morfoespecies de hongos endófitos que pertenecen al filo Ascomycota. La identificación molecular basada en el análisis de las secuencias de los espaciadores internos transcritos (ITS) amplificadas por PCR mostró que seis de los hongos más frecuentes corresponden a Remotididymella anthropophila y Diaporthe caatingaensis y a los géneros Diaporthe, Phomopsis y Fusarium. En ensayos de antagonismo múltiple, siete morfoespecies mostraron actividad antagónica fuerte contra los patógenos Fusarium oxysporum, F. proliferatum y Stemphylium vesicarium dos hongos endófitos pertenecen a Alternaria alternata, otro a Trichoderma longibrachiatum y otros dos son de los géneros Alternaria y Phomopsis. Mientras que Nigrospora oryzae fue el único endófito más frecuente y con actividad antagónica contra los tres patógenos. En ensayos de cultivo dual, los endófitos con actividad antagónica fuerte inhibieron de 37 al 80% el crecimiento micelial de F. oxysporum y F. proliferatum, pero en el ensayo de alimento envenenado, T. longibrachiatum inhibió el crecimiento micelial de los dos patógenos en 79 y 66%, respectivamente. Por primera vez se reporta a R. anthropophila como un hongo endófito, así como la identificación y la actividad antagónica de hongos endófitos de A. pichichensis.

Alternaria porricauses purple blotchdisease in onion and beneficial fungi of the genusTrichodermacan be used for its biocontrol,but knowledge of the mechanisms of the defense response in the interaction of onion plants with TrichodermaandA. porriis limited.In this study, the activity of defense enzymes: glucanases, chitinases, catalasesand peroxidasesin onion plants in the interaction with the isolate To ofTrichoderma asperellumandA. porriwas evaluated.The isolate To ofT. asperellumwas selected because it stood out for its antagonistic activity againstA. porricompared to that of anotherisolateofT. asperellum(TC1 and TC2) and ofT. harzianumandT. atroviridae. Withthe method of dual culture and cellophane paper, the isolate To inhibited the mycelial growth ofA. porriin 56 and 53%, respectively and showed mycoparasitic activity. Theactivity of enzymes depended on the interaction of onion plants with the isolate To ofT. asperellumandA. porri.The activity of glucanases and chitinases increased with the isolateofT. asperellumand was repressed withA. porri.The activity of catalases was induced withA. porriand the activity of peroxidases increased with both microorganisms.In conclusion, the defense mechanisms of onion plants are regulated by the interaction withT. asperellumandA. porriand both microorganisms; aspect tobeconsider in the biocontrol of onion pathogens with the isolate To ofT. asperellum., Alternaria porri causa la enfermedad mancha púrpura en cebolla y los hongos benéficos del género Trichoderma pueden ser usados para su biocontrol, pero es limitado el conocimiento de los mecanismos de la respuesta de defensa en la interacción de plantas de cebolla con Trichoderma y A. porri. En este estudio se evalúo la actividad de las enzimas de defensa: glucanasas, quitinasas, catalasas y peroxidasa en plantas de cebolla en la interacción con el aislado To de Trichoderma asperellum y A. porri. El aislado To de T. asperellum se seleccionó porque destacó por su actividad antagónica contra A. porri en comparación con la de otros aislados de T. asperellum (TC1 y TC2) y de T. harzianum y T. atroviridae. Con el método de cultivo dual y papel celofán,el aislado To inhibió el crecimiento micelial de A. porri en 56 y 53%, respectivamente y mostró actividad micoparasítica. La actividad de las enzimas dependió de la interacción de las plantas de cebolla con el aislado To de T. asperellum y A. porri. La actividad de glucanasas y quitinasas aumentó con el aislado de T. asperellum y se reprimió con A. porri. La actividad de catalasas se indujo con A. porri y la actividad de peroxidasas aumentó con ambos microorganismos. En conclusión, los mecanismos de defensa de plantas de cebolla son regulados por la interacción con T. asperellum y A. porri y ambos microorganismos; aspecto a considerar en el biocontrol de patógenos de cebolla con el aislado To de T. asperellum

Ruta graveolens L. is a plant of agricultural interest due to its biological activity against phytopathogenic microorganism. This activity has been attributed to the presence of alkaloids, furanocoumarins, terpenes and fatty acids. The accumulation of these compounds is affected by environmental factors. The aim of this work was to analyze the seasonal variation the chemical profile of rue and to evaluate the biological activity against phytopathogenic fungi. Extracts were obtained in January, April, June and September 2017, chemically characterized by GC-MS. The antifungal activity was determined by absorbance, four concentrations were evaluated: 4, 8, 16 and 32 mg/mL. In extracts from the aerial parts, fatty acids were the most abundant group in the January sample (29.7%), and alkaloids in the April and June (27.7%) samples. In extracts from the roots, alkaloids were the most abundant group in the four collections. The highest percentage of growth inhibition on Fusarium and Stemphylium was obtained with the extracts of the January sample. Ruta graveolens can be considered an alternative for the management of phytopathogenic fungi of crops of economic importance.

Cedrus atlantica is an ornamental plant used to decorate parks and gardens. In order to micropropagate quality material of this plant, an in vitro multiplication protocol was implemented. For this, the axillary buds were used as explants which were disinfected with sodium hypochlorite 10% for 15 min, treatment with which obtained 83% aseptic material. Explants culture was performed in the basal medium McCown’s Woody Plant (WPM) added with activated carbon (1g L-1) and cysteine (25 mg L-1), which allowed to obtain crops without oxidation features. In the multiplication stage with the use of benzyl amino purine (5 mg L-1) obtained up to 5 shoots per explant, which showed an increase of 1.4 cm. However, indole butyric acid at 2.5 and 5 mg L-1 did not induce root formation in vitro shoots. Keywords: cedar; bud; micropropagation; woody plants, Cedrus atlantica es una planta ornamental utilizada para la decoración de parques y jardines. Con el fin de micropropagar material de calidad de esta planta, se implementó un protocolo de multiplicación in vitro. Para ello, como explantes se usaron las yemas axilares que se desinfestaron con hipoclorito de sodio al 10% por 15 min, tratamiento con lo que se obtuvo un 83% de material aséptico. El cultivo de los explantes se realizó en el medio basal McCown’s Woody Plant (WPM) adicionado con carbón activado (1 g L-1) y cisteína (25 mg L-1), lo que permitió obtener cultivos sin rasgos de oxidación. En la etapa de multiplicación con el uso de la bencil amino purina (5 mg L-1) se obtuvieron hasta 5 brotes por explante, que presentaron un crecimiento de 1.4 cm. Sin embargo, el ácido indol butírico a 2.5 y 5 mg L-1 no indujo la formación de raíces en los brotes in vitro. Palabras clave: cedro; brotación; micropropagación; plantas leñosas

Lupinus seeds are characterized by elevated contents of high quality protein, so they find uses in both human and animal nutrition. However, little is known about possible bioactive compounds that could be beneficial to health. Lunasin is a 43 amino acid residue peptide isolated by the group of Prof. de Lumen (University of California, Berkeley) from the albumin protein fraction of soybean. Its cancer chemopreventive properties have been demonstrated by in vitro and in vivo assays; currently other plants are being investigated as possible sources of this peptide. This study aimed to detect lunasin in two cultivated and two wild species of Lupinus. Lunasin detection using lunasin monoclonal antibodies was carried out on total protein extracts as well as soluble fractions of defatted flour from seeds with and without testa. Soy (Glycine max) seed extracts served as positive control. Results showed the presence of lunasin in G. max protein fractions of albumin, globulin, and glutelin. Lunasin was found in prolamins fraction of L. albus seeds with testa; whereas it was found in albumin and glutelin fractions of seeds without testa of L. montanus and L. campestris, respectively. Lunasin was not detected in protein extracts of seeds without testa of L. albus and seed with and without testa of L. mutabilis. Peptide bands of molecular weights greater than 25 kDa were detected in the fractions of albumin, globulin and glutelin of all evaluated Lupinus species, suggesting presence of lunasin-related peptides.