Biocontrol con levaduras de Penicillium expansum y Botrytis cinerea en manzana Golden Delicious

Los hongos Penicillium expansum y Botrytis cinerea son los principales patógenos causantes de las pérdidas poscosecha en manzanas producidas en Chihuahua, México. Para el control de estos patógenos generalmente se utilizan fungicidas sintéticos. Para evitar la acumulación de residuos químicos sobre los frutos y la generación de resistencia en el patógeno como consecuencia del uso intensivo de los fungicidas sintéticos, el control biológico es cada vez es más utilizado como estrategia alternativa para el control de diversos fitopatógenos. En este estudio se evaluó la eficiencia como agentes de biocontrol de las levaduras nativas de la región de Cuauhtémoc, Chihuahua, México: Rhodotorula glutinis, R. mucilaginosa, y dos cepas de Candida oleophila (L-06 y L07), sobre P. expansum y de B. cinerea inoculados en manzanas Golden Delicious. Se evaluaron también las levaduras Cryptococcus flavus, C. albidus y C. laurentii. Solamente las cepas nativas de C. oleophila, L- 06 y L-07 redujeron la severidad de las lesiones provocadas por P. expansum en un 77 y 69%, respectivamente; mientras que R. mucilaginosa redujo la severidad en un 21%. Las cepas L-07 y L-06 de C. oleophila, fueron las más eficientes para el control de B. cinerea con reducciones del daño en 73 y 57%, respectivamente. C. flavus, C. albidus y R. mucilaginosa, aunque en menor grado que C. oleophila, también redujeron la severidad de las lesiones causadas por B. cinerea. Las cepas nativas de C. oleophila tienen gran potencial para el biocontrol de P. expansum y B. cinerea en manzana en poscosecha. Abstract Penicillium expansum Link and Botrytis cinerea are among the most common pathogens causing postharvest losses in apples produced in Chihuahua, Mexico. Synthetic fungicides are still commonly used to control rots caused by these fungi on apples, although most Penicillium and Botrytis species have developed resistance to most of the fungicides that are used for their control. An alternative to the use of chemical control is the use of microorganisms that are capable of controlling phytopathogenic fungi and avoiding the chemical residues on the fruit. Efficiency as biocontrol agents of the following yeast native to the region of Cuauhtemoc, Mexico was evaluated: Rhodotorula glutinis, R. mucilaginosa, and two Candida oleophila strains (L-06 y L07), to biocontrol P. expansum and B. cinerea, on Golden Delicious apples. Cryptococcus flavus, C. albidus and C. laurentii were also evaluated. Only native strains Candida oleophila L-06 and L-07 reduced the severity of lesions caused by P. expansum by 77 and 69%, respectively; while R. mucilaginosa reduced lesion severity to 21%. L-07 and L-06 C. oleophila strains were the most efficient to control B. cinerea with damage reduction of 73 and 57%, respectively. Cryptococcus flavus, C. albidus and R. mucilaginosa, although less than C. oleophila, also reduced lesion severity caused by B. cinerea, C. oleophila native strains have a great potential for biocontrol P. expansum and B. cinerea on postharvest apples. Keywords: Candida oleophila, Rhodotorula spp., Cryptococcus spp., postharves

Effect of the harvest date, calcium and other chemicals on the quality and storability of ‘Golden Smoothie’ apples

Apples cultivated in Mexico generally are smaller and softer than those produced in other geographical latitudes considered as optimal for apple production. The aim of this evaluation was determine the effect of applications with calcium, nitrogen, potassium, magnesium, sulfur and naphthaleneacetic acid (NAA), as well as the harvest date on the quality of apple fruits. ‘Golden Smoothie’ apple trees were treated foliarly with CaCl2 with and without NAA, and with a mixture of N, K, Mg and S or gypsum applied to soil for two years. Apples were harvested at 141 (regular harvest date), 161 (mid-late harvest) and 171 days (late harvest) after full bloom (DAFB) and evaluated for quality at harvest time and during their storage at 0°C for up to 179 days. Foliar applications of CaCl2 significantly increased the calcium content in fruit and leaves, but fruit quality, including firmness, was not influenced. Fertilization of soil with the mixture of nutrients, including CaSO4, did not influence the fruit quality. Lately harvested fruit was 14.9% heavier but 17.1% softer than fruit picked at the commercial harvest date. Delaying of fruit harvest reduced about 43 d the storability of fruit. Based in these results, the relative softness of apples grown in Mexico is not related with its calcium content, hence unlikely to be overcome with the application of this mineral. Even in the control fruits, both seasons, the stored fruits do not show some physiological disorder as bitter pit.  Objective: Apples cultivated in Mexico generally are smaller and softer than those produced in other geographical latitudes considered as optimal for apple production. The aim of this evaluation was determine the effect of applications with calcium, nitrogen, potassium, magnesium, sulfur and naphthaleneacetic acid (NAA), as well as the harvest date on the quality of apple fruits. Methodology ‘Golden Smoothie’ apple trees were treated foliarly with CaCl2 with and without NAA, and with a mixture of N, K, Mg and S or gypsum applied to soil for two years. Apples were harvested at 141 (regular harvest date), 161 (mid-late harvest) and 171 days (late harvest) after full bloom (DAFB) and evaluated for quality at harvest time and during their storage at 0°C for up to 179 days. Results: Foliar applications of CaCl2 significantly increased the calcium content in fruit and leaves, but fruit quality, including firmness, was not influenced. Fertilization of soil with the mixture of nutrients, including CaSO4, did not influence the fruit quality. Lately harvested fruit was 14.9% heavier but 17.1% softer than fruit picked at the commercial harvest date. Delaying of fruit harvest reduced about 43 d the storability of fruit. Based in these results, the relative softness of apples grown in Mexico is not related with its calcium content, hence unlikely to be overcome with the application of this mineral. Conclusions: Even in the control fruits, both seasons, the stored fruits do not show some physiological disorder as bitter pi

Gamificación en Iberoamérica. Experiencias desde la comunicación y la educación

La presente obra capitular es el resultado de las investigaciones sobre las aplicaciones de la gamificación en contextos múltiples, emergentes provenientes de las comunicaciones presentadas en el Simposio 06 del III Congreso Internacional Comunicación y Pensamiento (Sevilla, España), así como de aquellas presentadas por los miembros del Gamelab UPS, del Proyecto I+D+i Coordinado “Competencias mediáticas de la ciudadanía en medios digitales emergentes (smartphones y tablets): Prácticas innovadoras y estrategias educomunicativas en contextos múltiples” (EDU2015-64015-C3-1-R) (MINECO/FEDER), de la “Red de Educación Mediática” del Programa Estatal de Investigación Científica-Técnica de Excelencia, Subprograma Estatal de Generación de Conocimiento (EDU2016-81772-REDT), financiados por el Fondo Europeo de Desarrollo Regional (FEDER) y Ministerio de Economía y Competitividad de España. En este sentido se busca construir, desde una mirada dual desde Europa y América Latina el primer libro iberoamericano de gamificación, avalado por el Gamelab de la Universidad Politécnica Salesiana (Ecuador), el Proyecto I+D+i EDU2015-64015-C3-1-R, la Red Interuniversitaria Euroamericana de Investigación sobre Competencias Mediáticas para la Ciudadanía (Alfamed), el Laboratorio de Estudios en Comunicación (Ladecom) y el Grupo de Investigación Ágora (PAI-HUM-648) de la Universidad de Huelva (España) y el Grupo de Investigación Estructura, Historia y Contenidos de la Comunicación GREHCCO

Productos alternativos a la aminoetoxivinilglicina para el control de la producción de etileno en manzana 'Golden Delicious'

Chihuahua produce el 66 % de la manzana (Malus x domestica Borkh) a nivel nacional, siendo el cultivar ‘Golden Delicious’ el de mayor superficie plantada. La necesidad de controlar la maduración de la fruta para programar la cosecha, ha condicionado el uso de productos a base de la aminoetoxivinilglicina (AVG), un inhibidor de la síntesis del etileno, y por lo tanto de la maduración de los frutos climatéricos. Este producto es eficaz, pero de alto costo. En este estudio se evaluó la eficiencia de productos alternativos al AVG de menor costo. Se asperjaron manzanos ‘Golden Delicious’ en precosecha durante el ciclo 2008, con los tratamientos: ácido salicílico (AS; 1, 0.1 y 0.01 μM), cobalto (40, 60 y 80 mg Co++·L-1), ácido cítrico (AC; 533 mg·L-1) y AVG (123 mg·L-1) y agua como testigo. Los tratamientos de AS (0.01 y 1.0 μM) y de AC redujeron significativamente la concentración interna de etileno en los frutos, en comparación con el testigo, y a un nivel similar al AVG, con concentraciones de etileno de 0.6, 0.6, 0.4, 1.7 y 0.4 ppm, respectivamente. Los tratamientos con cobalto, a 40 y 80 mg Co++·L-1, retrasaron el pico climatérico en tres semanas. Los tratamientos con AS y cobalto indujeron frutos con color de cáscara más verde y con menor concentración de sólidos solubles, indicando un estado menos avanzado de maduración. Los tratamientos precosecha con AS, AC, y cobalto, representan una herramienta en el control de la maduración de manzanas ‘Golden Delicious’. Abstract Chihuahua produces 66 % of the apple (Malus x domestica Borkh) production in Mexico, being ‘Golden Delicious’ apple cultivar the most widely planted. The need to control fruit maturation in order to schedule harvest has made the use of aminoethoxyvinylglicine (AVG) almost a must, since it is an efficient ethylene synthesis inhibitor, and therefore a retardant of the maturation process in climacteric fruits; however it is an expensive product too. In this trial the effectiveness of alternative products to AVG, at a lower sell price, were evaluated. ‘Golden Delicious’ apple trees were sprayed before harvest during the 2008 season with: salicylic acid (AS; 1.0, 0.1 and 0.01 μM), cobalt (40, 60 and 80 mg Co++·L-1), citric acid (AC; 533 mg L-1), AVG (123 mg·L-1) and water as control. The treatments with AS (0.01 and 1.0 μM) and with AC reduced the internal concentration of ethylene in the fruit respect to control, and to a similar level as AVG did it, with internal ethylene concentration of 0.6, 0.6, 0.4, 1.7 and 0.4 ppm, respectively. Treatments with cobalt at 40 and 80 mg Co++·L-1 delayed in three weeks the climacteric peak. AS and cobalt produced fruits with greener peel and lower level of soluble solids, indicating a less advanced maturation stage. Therefore, the preharvest treatments with AS, AC and cobalt offer to growers a tool to control the maturation of ‘Golden Delicious’ apple fruits. Keywords: Malus x domestica, citric acid, salicylic acid, cobalt

Raleo químico de flores de manzano (Malus x domestica Borkh.) 'Golden Delicious' y 'RedChief Delicious'

Aunque el raleo es una práctica común en la región productora de manzana (Malus x domestica Borkh.) del estado de Chihuahua, aún es frecuente que se lleve a cabo de manera manual, tardía, poco eficiente y costosa. El raleo químico es una práctica cada vez más común. En manzano, el raleo de flores o frutos incrementa la calidad de los frutos y reduce la alternancia en la producción. Para maximizar los beneficios de esta práctica, se evaluó la eficiencia de los siguientes compuestos asperjados durante la floración: ácido naftalenacético, cianamida hidrogenada, tiosulfato de amonio, bencil adenina, ácido giberélico y una mezcla de cal-azufre y aceite de pescado como raleadores químicos de flores en los cultivares Golden Delicious y RedChief Delicious. Otro tratamiento consistió en las aplicaciones de la mezcla de cal-azufre y aceite de pescado en floración, además de una aspersión con ácido naftalenacético en post-floración. Los resultados se compararon con un testigo con un raleo manual tardío y un tratamiento con raleo manual en floración. En ambos cultivares, el tratamiento de cal-azufre en floración y ácido naftalenacético en post-floración, redujo significativamente el cuajado de frutos sin reducir el rendimiento a cosecha. Además, con este mismo tratamiento se obtuvieron los frutos de mayor tamaño a la cosecha. Los tratamientos con cal-azufre y aceite de pescado provocaron roseteado en los frutos ‘Golden Delicious’. El tratamiento con ácido naftalenacético en floración redujo significativamente la alternancia de la producción observada en ‘Golden Delicious’. Abstract Although thinning is a common practice in the productive apple (Malus x domestica Borkh.) region in the state of Chihuahua, it is still often performed manually, belated, innefficient and costly. Chemical thinning is an increasingly common practice. In apple trees, flower or fruit thinning increases the fruit quality and reduces alternate bearing in the apple production. To maximize the benefits of this practice, it was assessed efficiency of the following products: naphthaleneacetic acid, hydrogen cyanamide, ammonium thiosulfate, benzyladenine, gibberelic acid, and a mixture of lime-sulfur and fish oil as chemical thinners of flowers in the cultivars Golden Delicious and RedChief Delicious, sprayed during bloom was evaluated. Another treatment consisted of the application of the lime-sulfur mixture and fish oil at bloom plus a spraying with naphthaleneacetic acid at post-bloom stage. The results were compared with a late manual thinning as control, and with a treatment of manual thinning during bloom. In both cultivars, the treatment with lime- sulfur at bloom and naphthaleneacetic acid at post-bloom, significantly reduced fruit set without reducing crop yield. Furthermore, there were obtained larger fruits at harvest with this same treatment. Treatments with lime-sulfur and fish oil resulted in russeting on 'Golden Delicious' fruits. Naphthaleneacetic acid treatment during bloom significantly reduced alternate bearing observed in cv. 'Golden Delicious'. Keywords: Malus x domestica Borkh., fruit set, return bloom, russeting

Proteína inhibidora de la poligalacturonasa en manzana mexicana (Malus domestica Borkh)

La poligalacturonasa (PG) es una de las enzimas responsables de la pérdida de firmeza de la manzana. La determinación de la presencia y actividad de la proteína inhibidora de la poligalacturonasa (PIPG) es información de alta relevancia como base para otros trabajos, como los relacionados a la incidencia y severidad de enfermedades fungosas en poscosecha, como información básica para su control. Con esta finalidad, se determinó la presencia y actividad de la PIPG en frutos de manzana por medio de un análisis de difusión radial, determinando también índices de madurez y contenido de proteínas totales. Los 20 frutos de cada cultivar, provenientes de una huerta comercial en Cuauhtémoc, Chihuahua, se cosecharon por fecha, pizcando al  azar, bajo un diseño experimental completamente al azar.  ABSTRACT Polygalacturonase (PG) is one of the enzymes responsible for apple fruit firmness loss, therefore, the determination of the presence and activity of polygalacturonase inhibitor protein  (PGIP) is highly relevant information for those studies related to incidence and severity of postharvest fungal diseases and their control. PGIP presence and activity were determined on apple fruit by a radial diffusion analysis, maturity indexes and  total protein content were also quantified. Twenty apple fruits   of each cultivar were sampled from a commercial orchard in  Cuauhtemoc, Chihuahua, Mexico. Apple fruits were sampled  by date, picking them at random, under a completely randomized experimental design

Growth Promotion of <i>Phaseolus vulgaris</i> and <i>Arabidopsis</i> <i>thaliana</i> Seedlings by Streptomycetes Volatile Compounds

Streptomyces are recognized as antipathogenic agents and plant-growth-promoting rhizobacteria. The objective of this study was to evaluate the capacities of four antifungal Streptomyces strains to: produce the substances that are involved in plant growth; solubilize phosphates; and fix nitrogen. The effects of the volatile organic compounds (VOCs) that are emitted by these strains on the growth promotion of Arabidopsis thaliana and Phaseolus vulgaris L. (var. Pinto Saltillo) seedlings were also tested. All of the Streptomyces strains produced indole-3-acetic acid (IAA) (10.0 mg/L to 77.5 mg/L) and solubilized phosphates, but they did not fix nitrogen. In vitro assays showed that the VOCs from Streptomyces increased the shoot fresh weights (89–399%) and the root fresh weights (94–300%) in A. thaliana seedlings; however, these effects were less evident in P. vulgaris. In situ experiments showed that all the Streptomyces strains increased the shoot fresh weight (11.64–43.92%), the shoot length (11.39–29.01%), the root fresh weight (80.11–140.90%), the root length (40.06–59.01%), the hypocotyl diameter (up to 6.35%), and the chlorophyll content (up to 10.0%) in P. vulgaris seedlings. 3-Methyl-2-butanol had the highest effect among the ten pure VOCs on the growth promotion of A. thaliana seedlings. The tested Streptomyces strains favored biomass accumulation in A. thaliana and P. vulgaris seedlings

The genomic history of the Iberian Peninsula over the past 8000 years

We assembled genome-wide data from 271 ancient Iberians, of whom 176 are from the largely unsampled period after 2000 BCE, thereby providing a high-resolution time transect of the Iberian Peninsula. We document high genetic substructure between northwestern and southeastern hunter-gatherers before the spread of farming. We reveal sporadic contacts between Iberia and North Africa by ~2500 BCE and, by ~2000 BCE, the replacement of 40% of Iberia’s ancestry and nearly 100% of its Y-chromosomes by people with Steppe ancestry. We show that, in the Iron Age, Steppe ancestry had spread not only into Indo-European–speaking regions but also into non-Indo-European–speaking ones, and we reveal that present-day Basques are best described as a typical Iron Age population without the admixture events that later affected the rest of Iberia. Additionally, we document how, beginning at least in the Roman period, the ancestry of the peninsula was transformed by gene flow from North Africa and the eastern Mediterranean.J.M.F., F.J.L.-C., J.I.M., F.X.O., J.D., and M.S.B. were supported by HAR2017-86509-P, HAR2017-87695-P, and SGR2017-11 from the Generalitat de Catalunya, AGAUR agency. C.L.-F. was supported by Obra Social La Caixa and by FEDER-MINECO (BFU2015- 64699-P). L.B.d.L.E. was supported by REDISCO-HAR2017-88035-P (Plan Nacional I+D+I, MINECO). C.L., P.R., and C.Bl. were supported by MINECO (HAR2016-77600-P). A.Esp., J.V.-V., G.D., and D.C.S.-G. were supported by MINECO (HAR2009-10105 and HAR2013-43851-P). D.J.K. and B.J.C. were supported by NSF BCS-1460367. K.T.L., A.W., and J.M. were supported by NSF BCS-1153568. J.F.-E. and J.A.M.-A. were supported by IT622-13 Gobierno Vasco, Diputación Foral de Álava, and Diputación Foral de Gipuzkoa. We acknowledge support from the Portuguese Foundation for Science and Technology (PTDC/EPH-ARQ/4164/2014) and the FEDER-COMPETE 2020 project 016899. P.S. was supported by the FCT Investigator Program (IF/01641/2013), FCT IP, and ERDF (COMPETE2020 – POCI). M.Si. and K.D. were supported by a Leverhulme Trust Doctoral Scholarship awarded to M.B.R. and M.P. D.R. was supported by an Allen Discovery Center grant from the Paul Allen Foundation, NIH grant GM100233, and the Howard Hughes Medical Institute. V.V.-M. and W.H. were supported by the Max Planck Society

The genomic history of the Iberian Peninsula over the past 8000 years

We assembled genome-wide data from 271 ancient Iberians, of whom 176 are from the largely unsampled period after 2000 BCE, thereby providing a high-resolution time transect of the Iberian Peninsula. We document high genetic substructure between northwestern and southeastern hunter-gatherers before the spread of farming. We reveal sporadic contacts between Iberia and North Africa by ~2500 BCE and, by ~2000 BCE, the replacement of 40% of Iberia's ancestry and nearly 100% of its Y-chromosomes by people with Steppe ancestry. We show that, in the Iron Age, Steppe ancestry had spread not only into Indo-European-speaking regions but also into non-Indo-European-speaking ones, and we reveal that present-day Basques are best described as a typical Iron Age population without the admixture events that later affected the rest of Iberia. Additionally, we document how, beginning at least in the Roman period, the ancestry of the peninsula was transformed by gene flow from North Africa and the eastern Mediterranean.J.M.F., F.J.L.-C., J.I.M., F.X.O., J.D., and M.S.B. were supported by HAR2017-86509-P, HAR2017-87695-P, and SGR2017-11 from the Generalitat de Catalunya, AGAUR agency. C.L.-F. was supported by Obra Social La Caixa and by FEDER-MINECO (BFU2015- 64699-P). L.B.d.L.E. was supported by REDISCO-HAR2017-88035-P (Plan Nacional I+D+I, MINECO). C.L., P.R., and C.Bl. were supported by MINECO (HAR2016-77600-P). A.Esp., J.V.-V., G.D., and D.C.S.-G. were supported by MINECO (HAR2009-10105 and HAR2013-43851-P). D.J.K. and B.J.C. were supported by NSF BCS-1460367. K.T.L., A.W., and J.M. were supported by NSF BCS-1153568. J.F.-E. and J.A.M.-A. were supported by IT622-13 Gobierno Vasco, Diputación Foral de Álava, and Diputación Foral de Gipuzkoa. We acknowledge support from the Portuguese Foundation for Science and Technology (PTDC/EPH-ARQ/4164/2014) and the FEDER-COMPETE 2020 project 016899. P.S. was supported by the FCT Investigator Program (IF/01641/2013), FCT IP, and ERDF (COMPETE2020 – POCI). M.Si. and K.D. were supported by a Leverhulme Trust Doctoral Scholarship awarded to M.B.R. and M.P. D.R. was supported by an Allen Discovery Center grant from the Paul Allen Foundation, NIH grant GM100233, and the Howard Hughes Medical Institute. V.V.-M. and W.H. were supported by the Max Planck Society