Abstract Banana plantation are the fourth most important crop worldwide and the most important tropical fruit. Their cultivation is carried out in more than 120 countries, producing approximately 100 million tons per year. México is one of the principal banana producers and exporters. However, its quality is affected by diseases such as black sigatoka, which, since its first appearance in the country in 1981, has been the disease that generates the greatest economic losses, because it has not been able to eradicate due to the climatic conditions in which it spreads. The principal variables that affect black sigatoka’s presence are temperature and relative humidity; and if it is not controlled, the pathogen can reduce up to 50 % the bunch weight and causes losses up to 100 % of the production. This research paper proposes a fuzzy inference system Takagi-Sugeno type, with a constant output, to determine the risk of black sigatoka proliferation in banana crops, through the analysis of temperature (13-38 °C) and relative humidity (0-100 %). The fuzzy system was developed in two applications, 1) MATLAB fuzzy logic tool and, 2) the library JFuzzyLogic of JAVA language. For testing, historical data of monthly average of temperature and relative humidity were used, from january 2015 to june 2019, in Manzanillo, one of the cities with the greatest banana production in Colima state, México, obtaining similar results with both applications. For the system validation the determination coefficient ( r 2 ) was applied, with results greater than 0.9, demonstrating that the predictive model is acceptable. This research presents an innovative approach using a Takagi-Sugeno diffuse system with constant output that will help to prevent the risk of black sigatoka proliferation, allowing banana crop growers to have a tool to effectively fight the pathogen.

Resumen La plantación de plátano representa el cuarto cultivo más importante a nivel mundial y la fruta tropical de mayor importancia, su cultivo se realiza en más de 120 países, produciendo aproximadamente 100 millones de toneladas al año. México es uno de los principales países productores y exportadores de plátano. Sin embargo, su calidad se ve afectada por enfermedades tales como la sigatoka negra, que ha sido la enfermedad que genera mayores pérdidas económicas, puesto que no se ha logrado controlar debido a las condiciones climáticas en las que se propaga. Las principales variables que influyen en la aparición de la sigatoka negra son la temperatura y la humedad relativa; y si no se controla, el agente patógeno puede reducir hasta en 50 % del peso del racimo y causar pérdidas de hasta 100 % de la producción. Este trabajo de investigación propone un sistema de inferencia difuso tipo Takagi-Sugeno, con salida constante, para determinar el riesgo de proliferación de la sigatoka negra en cultivos de plátano, por medio del análisis de la temperatura (13-38 °C) y la humedad relativa (0-100 %). El sistema difuso se desarrolló en dos aplicaciones; siendo éstas, la herramienta de lógica difusa de MATLAB y la librería JFuzzyLogic del lenguaje JAVA; para las pruebas se utilizaron datos históricos del promedio mensual de temperatura y humedad relativa, desde enero de 2015 hasta junio de 2019, en Manzanillo, uno de los municipios de mayor producción de plátano del estado de Colima, obteniendo resultados similares con ambas aplicaciones. Para la validación del sistema se aplicó el coeficiente de determinación (r 2 ), debido a que esta métrica ha sido utilizada en trabajos previos de investigación, con resultados mayores a 0.9, demostrando que el modelo predictivo es aceptable. Esta investigación presenta un enfoque innovador utilizando un sistema de inferencia difuso tipo Takagi-Sugeno con salida constante que contribuye a prevenir el riesgo de proliferación de la sigatoka negra, permitiendo a los productores de cultivos de plátano tener una herramienta para combatir eficazmente el agente patógeno.

Resumo A Sigatoka-negra, causada pelo fungo Mycosphaerella fijiensis Morelat, é uma doença que afeta as folhas da bananeira, reduzindo a fotossíntese e ocasionando queda na produtividade. O controle baseia-se no uso de fungicidas; no entanto, essa prática eleva o custo de produção e pode causar impactos ambientais e na saúde. O plantio de cultivares resistentes mostra-se mais viável economicamente. O objetivo deste estudo foi realizar a fenotipagem de diploides, visando à identificação de genótipos resistentes. Foram fenotipados 31 acessos (30 com genoma AA e um com genoma AB), a partir da expressão dos sintomas da doença, por meio de escala de notas. Estimaramse a área abaixo da curva do progresso da doença (AACPD), o índice de severidade da doença (ID) e o índice de aumento da severidade da doença (AID). A variável AID mostrou-se eficiente na identificação de acessos de bananeira com resistência à Sigatoka-negra. O índice de seleção para o ranqueamento de acessos, com moderada resistência à Sigatoka-negra, permitiu identificar os genótipos com maior resistência quantitativa. Cinco acessos diploides foram resistentes (Krasan Saichon, Zebrina, Birmanie, Nº 118 e Tuu Gia), e oito moderadamente resistentes (PA Rayong, Pisang Cici, Malaccensis 1, 028003-01, Microcarpa, Pisang Lidi, Lilin e Malbut).

Abstract Black Sigatoka (black leaf streak disease) is caused by the fungus Mycosphaerella fijiensisMorelet. This phytopathogen colonizes banana leaves, resulting in reduced photosynthesis and decreased productivity. Fungicide applications are useful to control black Sigatoka; however, they increase production costs and can have adverse environmental and health impacts. The cultivation of resistant cultivars is regarded as a more economically viable option. The objective of this study was to perform diploid phenotyping in a set of wild banana accessions to identify resistant genotypes. A total of 31 accessions (30 with AA genome and one with AB genome) were phenotyped based on the presence of disease symptoms using a scoring scale. The area under the disease progress curve (AUDPC), the disease severity index (DI), and the disease severity increase index (DII) were estimated. The DII variable proved to be efficient in identifying banana accessions with black Sigatoka resistance. Likewise, the selection index for ranking accessions with moderate black Sigatoka resistance allowed us to identify those genotypes with the highest quantitative resistance. Five diploid accessions (Krasan Saichon, Zebrina, Birmanie, Nº 118, and Tuu Gia) were found to be resistant to this fungal disease; eight accessions (PA Rayong, Pisang Cici, Malaccensis 1, 028003- 01, Microcarpa, Pisang Lidi, Lilin, and Malbut) were moderately resistant.

Resumen El banano es uno de los cultivos comestibles más importante en el mundo, sin embargo, es atacado por diferentes patógenos, uno de los más destacados es el hongo Mycosphaerella fijiensis, agente causal de la Sigatoka Negra. Los problemas ambientales y económicos relacionados con los pesticidas usados para su control han estimulado la búsqueda de biomoléculas alternativas no contaminantes. En el grupo de Biotecnología de la Universidad de Antioquia se realizaron estudios previos buscando una alternativa biológica al control de M. fijiensis, en los cuales se determinó la capacidad antifúngica del hongo Ganoderma lucidum como antagonista y posteriormente como fuente de extractos proteicos con actividad inhibitoria in vitro y en plantas de invernadero; estos hallazgos fueron la base de este trabajo, que está enfocado en el estudio de la capacidad enzimática de las proteínas presentes en los extractos proteicos, debido a su capacidad potencial para degradar diferentes compuestos, incluyendo polisacáridos, lípidos, péptidos y ácidos nucleicos, que constituyen partes esenciales de una célula viva; por lo tanto, estos extractos pueden actuar como posibles agentes antifúngicos. En este estudio, los extractos proteicos de G. lucidum obtenidos a partir de cultivos en biorreactor (BIOFLO 110®) fueron caracterizados en términos de sus actividades enzimáticas: deoxyribonucleasa, ribonucleasa, proteasa, glucanasa y quitinasa. Los extractos también fueron fraccionados y cada fracción obtenida fue evaluada para la capacidad inhibitoria contra el hongo fitopatógeno M. fijiensis, y a través de los análisis de espectrometría de masas se confirmó la presencia de diferentes enzimas con potencial antifúngico.

Abstract Banana is one of the most important edible crops in the world, however, it’s attacked by different pathogens, one of the most prominent of these is the fungus Mycosphaerella fijiensis, causal agent of Black Sigatoka. The environmental and economic issues related to the pesticides used for its control have encouraged the search for cleaner alternative biomolecules. Previous studies were made by the Biotechnology group from the Universidad de Antioquia searching for a biological alternative for the control of M. fijiensis; in these the antifungal capacity of the fungus Ganoderma lucidum was determined as an antagonist and then as a source of protein extracts with inhibitory activity in vitro and in greenhouse plants; these findings were the foundation of this work, which focuses in the study of the enzymatic capacity of the proteins present in the protein extracts, due to their potential ability to degrade different compounds, including polysaccharides, lipids, peptides and nucleic acids, constituents of essential parts of a living cell; therefore these extracts can act as possible antifungal agents. In this study, protein extracts of G. lucidum obtained from bioreactor cultures (BIOFLO 110 ®) were characterized in terms of their deoxyribonuclease, ribonuclease, protease, glucanase and chitinase enzymatic activities. The extracts were also fractionated and each fraction obtained was evaluated for its inhibitory capacity against the phytopathogen fungus M. fijiensis, and through mass spectrometry analysis the presence of different enzymes with antifungal potential was confirmed.

Abstract: Black Sigatoka is the most destructive disease of the leaves of bananas. The increased resistance of the pathogen and the contamination caused by chemical fungicides have guided the search for control alternatives. The objective of the work was to determine the effect of the combination of extracts of garlic (Allium sativum) and clove (Syzygium aromaticum) in the development of Mycosphaerella fijiensis. The phytopathogen was grown in potato-dextrose-agar (PDA) media added with different concentrations of extracts. A factorial design of two factors at four levels was established. At higher concentration of garlic extract, less capacity to inhibit M. fijiensis colony. In contrast, the clove extract showed greater inhibition capacity at the higher concentration. The greatest inhibition of the growth, 39.6%, was with the mixture of 150 mg of garlic extract·ml-1 and 36 mg of clove extract·ml-1.

Resumen: La Sigatoka Negra es la enfermedad más destructiva del área foliar de plátanos y bananos. La incrementada resistencia del patógeno, y la contaminación provocada por los fungicidas químicos, han guiado a la búsqueda de alternativas para su control. El objetivo del trabajo fue determinar el efecto de la combinación de los extractos de ajo (Allium sativum) y clavo (Syzygium aromaticum) en el desarrollo de Mycosphaerella fijiensis. Después de aislar a M. fijiensis, fue cultivado en medios agar-dextrosa-papa (ADP) adicionados con diferentes concentraciones de los extractos etanólicos de las plantas mencionadas. Los tratamientos utilizados fueron el resultado de establecer un diseño factorial de dos variables a cuatro niveles. Los resultados mostraron que, a mayor concentración de ajo, menor capacidad de inhibir el desarrollo de la colonia de M. fijiensis. Contrariamente el extracto de clavo mostró mayor capacidad de inhibición a mayor concentración. Sin embargo, la mayor inhibición del desarrollo de la colonia del fitopatógeno, 39.6%, fue observada en ADP adicionada con la mezcla de 150 mg de extracto de ajo·ml-1 y 36 mg de extracto de clavo·ml-1. Se discute el posible mecanismo de acción de los extractos.

Abstract: Chemical control of black sigatoka in banana Mycosphaerella fijiensis has increased the selection pressure on the pathogen, a fact which in turn creates an environmental impact. The objective of this study was to evaluate the effect of essential Pimenta dioica, Piper auritum, Sysygium aromaticum, Cinnamomum zeylanicum, Origanum vulgare, Artemisia ludoviciana, and Origanum majorana oils on M. fijiensis growth under in vitro conditions, and to identify their active metabolites. The oils were obtained by hydrodistillation. M. fijiensis was isolated and developed on PDA culture medium. Thin layer chromatography (TLC) and column chromatography (CC) were used to identify the metabolites of each essential oil. Five concentrations: 50, 100, 500, 1000 y 5000 ppm of each oil were used. P. dioica, C. zeylanicum and O. vulgare oils had a significant effect with lower M. fijiensis mycelial growth at a concentration of 500 ppm, whereas the effect on O. majorana and A. ludoviciana was observed at a concentration of 1000 ppm. Cinnamic aldehyde was the main metabolite detected in C. zeylanicum species, and eugenol and carvacrol in P. dioica y O. vulgare species.

Resumen: El control químico de la sigatoka negra en banano Mycosphaerella fijiensis ha incrementado la presión de selección en el patógeno, con el consecuente impacto en el ambiente. El objetivo de este estudio, fue evaluar el efecto de los aceites esenciales de Pimenta dioica, Piper auritum, Syzygium aromaticum, Cinnamomum zeylanicum, Origanum vulgare, Artemisia ludoviciana y Origanum majorana, en el crecimiento micelial de M. fijensis en condiciones in vitro e identificar sus metabolitos activos. Los aceites se obtuvieron mediante el método de hidrodestilación. El patógeno se aisló y desarrolló en medio de cultivo PDA. Se usaron cinco concentraciones: 50, 100, 500, 1000 y 5000 ppm de cada aceite. Para identificar los metabolitos de cada uno de los aceites esenciales, se usó cromatografía en capa fina (CCF) y cromatografía en columna (CC). Los aceites de P. dioica, C. zeylanicum, O. vulgare presentaron menor crecimiento micelial de M. fijiensis a una concentración de 500 ppm; mientras que O. majorana y A. ludoviciana a 1000 ppm. El aldehído cinámico fue el principal metabolito detectado en la especie C. zeylanicum; el eugenol y carvacrol, en las especies P. dioica y O. vulgare.

Abstract Some cultivated varieties of banana (Musa spp.) -resistant to black Sigatoka disease, caused by Mycosphaerella fijiensis Morelet- have been subject to agronomical studies; however, the approval of these varieties is not successful because they are rejected for fresh consumption. An alternative for their use is to transform them into flour. The objective of this study was to determine the chemical and microbiological quality of banana flour from three cultivars resistant to this disease: Yangambi km 5 (AAA), FHIA-18 hybrid (AAAB), and Pisang Awak (ABB). The bunch and the fruit were characterized during the postharvest stage, and the chemical quality of the fruits was evaluated when the fruit reached its physiological maturity. In order to make flour, the bananas were washed with a chlorine solution, the peel was removed, the fruits were sliced, dehydrated at 60 °C -until a constant weight was achieved-, crushed, and sieved using a No. 70 sieve (212 µm). The flour was subject to proximate chemical and microbiological analysis. The experimental design was fully randomized with three treatments (the flour from each one of the three cultivars), all the evaluations were done in triplicate, the results were analyzed using the GLM procedure, and the means were compared using the Tukey test (p≤0.05). The Yangambi km 5 cultivar had the lightest bunches (14.66±2.65 kg); the FHIA-18 hybrid presented the heaviest fruits (120.67±11.1 g) and the thickest peels (0.33±0.02 cm); and the Pisang Awak cultivar had the highest pulp-shell ratio (2.16±0.24). The fruit of the Pisang Awak cultivar presented less moisture (64.02±0.54 %), more dry matter (35.97±0.96 %), and less total soluble solids (0.80±0.17 °Brix); the evaluated cultivars showed no differences in pH and titratable acidity. The Pisang Awak cultivar had the highest flour yield (35.73±1.24 %), less protein (2.79±0.06 %), and higher ethereal extract (0.67±0.01 %). The FHIA-18 hybrid had the highest protein (3.53±0.05 %) and ash content (2.06±0.16 %). The characteristics in physiological maturity of bananas bunches allowed to obtain flour with good quality variables.

Resumen Algunas variedades cultivadas de banano (Musa spp.) resistentes a la enfermedad de Sigatoka negra, causada por Mycosphaerella fijiensis Morelet, se han estudiado agronómicamente, pero la adopción de estas variedades no es efectiva pues son rechazadas para su consumo fresco. Una alternativa para su aprovechamiento es transformarlas en harina. El objetivo de este estudio fue determinar la calidad química y microbiológica de la harina de banano de tres cultivares resistentes a esta enfermedad: Yangambi km 5 (AAA), híbrido FHIA-18 (AAAB) y Pisang Awak (ABB). La caracterización poscosecha se realizó al racimo y al fruto, y la calidad química de los frutos se evaluó en madurez fisiológica. Para obtener harina, los frutos se lavaron con una solución clorada, la cáscara se eliminó, se rebanaron, deshidrataron a 60 °C hasta peso constante, se trituraron y tamizaron (tamiz de 212 µm; N° 70). En la harina se realizaron análisis químico proximal y microbiológico. El diseño experimental fue completamente al azar con tres tratamientos (la harina de cada uno de los tres cultivares), todas las evaluaciones se hicieron por triplicado, los resultados se analizaron con el procedimiento GLM y las medias se compararon con la prueba de Tukey (p≤0.05). El cultivar Yangambi km5 presentó el peso menor de racimo (14.66±2.65 kg), el híbrido FHIA-18 presentó el peso mayor de fruto (120.67±11.1 g) y el grosor mayor de cáscara (0.33±0.02 cm), y el cultivar Pisang Awak tuvo la relación mayor pulpa-cáscara (2.16±0.24). El fruto del cultivar Pisang Awak presentó menor humedad (64.02±0.54 %), mayor materia seca (35.97±0.96 %) y menos sólidos solubles totales (0.80±0.17 °Brix); en pH y acidez titulable no hubo diferencias entre los cultivares evaluados. El cultivar Pisang Awak tuvo el rendimiento mayor de harina (35.73±1.24 %), menos proteína (2.79±0.06 %) y extracto etéreo mayor (0.67±0.01 %). El híbrido FHIA-18 presentó el mayor contenido de proteína (3.53±0.05 %) y de cenizas (2.06±0.16 %). Las características en madurez fisiológica del racimo de banano permitieron obtener harina con buenas variables de calidad.

Resumo A bananeira (Musa acuminata - AAA) ‘Grande Naine’, no município de Angra dos Reis (RJ), tem sido afetada pelo agente da Sigatoka-Negra, Mycosphaerella fijiensis(atualmente denominado de Pseudocercospora fijiensis), ocasionando perdas aos produtores locais em sua maioria pequenos produtores e de baixa renda. Uma vez que a Sigatoka-Negra foi assinalada no município citado, objetivou-se determinar a eficácia do controle através de medida de Cirurgia ou Desfolha Cirúrgica; e avaliar o efeito desta sobre as caraterísticas de produtividade da bananeira. Para tal finalidade, foi idealizado na forma de blocos inteiramente casualizados, contendo três blocos, e cada bloco tinha cinco plantas com tratamento (Cirurgia) e cinco plantas sem tratamento (Controle), num total de 30 plantas com infecção fúngica. A cada 15 dias, foram feitos os tratamentos, com avaliações mensais da severidade (Média Ponderada da Infecção - MPI), pelo método de Stover modificado por Gauhl. Os resultados obtidos ao final do ensaio evidenciaram diferenças significativas em todas as variáveis (Severidade, folha mais jovem doente, peso e tamanho dos cachos) avaliadas, sendo que o tratamento com Cirurgia proporcionou redução da severidade (MPI) em torno de 58%, confirmando assim que as plantas receberam um tratamento adequado, segundo resultados obtidos para esta metodologia, e contribuindo com o aumento da área foliar sadia nas folhas mais jovens da planta, enquanto nas plantas sem a Cirurgia (Controle) a severidade aumentou 14,8% em comparação com a avaliação inicial do MPI, e por consequência tendo menor área foliar sadia para a realização da fotossíntese e dos demais processos fisiológicos da planta. Nas variáveis da produção, para o peso dos cachos, número e tamanho dos frutos, as diferenças foram significativas (Pr>F = 0,0001), chegando a ter um aumento no rendimento de até 300%, quando comparado com o Controle. Trata-se, portanto, de um método eficaz de controle para o fitopatógeno da sigatoka-negra, inédita no Estado do Rio de Janeiro, e que trará benefícios diretos à Agricultura Familiar para a região de incidência dessa doença em bananeira.

Abstract ‘Grande Naine’ banana (Musa acuminata - AAA) in the municipality of Angra dos Reis (RJ) has been affected by the Black Sigatoka agent, fijiensis Mycosphaerella(current name Pseudocercospora fijiensis); causing losses to local producers, mostly small producers and low-income producers. Since Black Sigatoka was reported in the mentioned municipality, it was aimed to determine control efficiency through surgical measurement or surgical defoliation and to evaluate its effect on banana productivity characteristics. For this purpose, treatment was designed in the form of completely randomized blocks containing three blocks, each block with five plants with treatment (Surgery) and five plants without treatment (Control), in a total of 30 plants with fungal infection. Treatments were performed every 15 days with monthly severity assessments (Weighted Mean of Infection - MPI) by the method of Stover modified by Gauhl. The results obtained at the end of the trial showed significant differences in all variables (Severity, youngest leaf spotted, bunch weight and fruit size), and treatment with surgery provided reduction in severity (MPI) around 58%, thus confirming that plants received adequate treatment according to the results obtained for this methodology, and, contributing to the increase of the healthy leaf area in the youngest leaves, whereas in plants without surgery (Control), severity increased by 14.8% in comparison to the initial MPI evaluation, consequently having a smaller healthy leaf area for the accomplishment of photosynthesis and other physiological processes. In production variables bunch weight, fruit size and number of fruits, differences were significant (Pr> F = 0.0001), reaching an increase in yield of up to 300% when compared to Control. It is therefore an effective method for the control of phytopathogen black sigatoka unpublished in the state of Rio de Janeiro and that will bring direct benefits for Family Agriculture in the region of incidence of this banana disease.

RESUMO O objetivo do trabalho foi avaliar as características químicas, físicas e sensoriais dos frutos de banana (Musa spp.) cultivar Caipira e Pacovan Ken, resistentes à Sigatoka Negra (Mycosphaerella fijiensis Morelet), com e sem embalagem de polietileno de baixa densidade, associada à refrigeração durante o período de armazenamento pós-colheita. O experimento foi instalado em 2012, no delineamento de blocos casualizados em esquema de parcelas subdivididas no tempo, tendo nas parcelas um fatorial 3 x 2 referente aos frutos sem embalagem e com embalagem de polietileno de 10 e 16 µm e duas cultivares Caipira e Pakovan Ken, e nas subparcelas as avaliações em intervalos de seis dias (0; 6; 12; 18 e 24) e dois dias (0; 2; 4; 6 e 8), para frutos armazenados nas temperaturas de 12; 15 e 25 ºC, respectivamente. As variáveis avaliadas foram: sólidos solúveis, acidez titulável, relação sólidos solúveis/ acidez titulável, potencial hidrogeniônico, açúcares solúveis totais, coloração do fruto e análise sensorial. A embalagem de polietileno associada à refrigeração manteve os frutos armazenados por 24 dias, mantendo as características pós-colheita adequadas ao consumo. A cultivar Pakovan Ken destacou-se quando comparada à Caipira, apresentando valores superiores nos atributos dos frutos avaliados.

ABSTRACT The aim of this work was to evaluate the chemical, physical and sensory characteristics of the Caipira and Pakovan Ken cultivars of the banana (Musa spp.), resistant to black Sigatoka (Mycosphaerella fijiensis Morelet), both with and without low-density polyethylene wrapping and together with refrigeration during the period of post-harvest storage. The experiment was carried out in 2012, in a randomised block design and an arrangement of lots split over time. A 3 x 2 factorial scheme was used for the lots, consisting of fruit with no wrapping and fruit wrapped in 10 and 16 µm polyethylene film, and two cultivars, Caipira and Pakovan Ken. The sub-lots consisted of evaluations made at intervals of six days (0, 6, 12, 18 and 24) and of two days (0, 2, 4, 6 and 8), for fruit stored at temperatures of 12, 15 and 25 ºC respectively. The following variables were evaluated: soluble solids, titratable acidity, ratio of soluble solids to titratable acidity, hydrogen potential, total soluble sugars, fruit colouration and sensory analysis. The polyethylene film together with the refrigeration enabled the fruit to be stored for 24 days, maintaining post-harvest characteristics suitable for consumption. The Pakovan Ken cultivar stood out when compared to the Caipira, with higher values for the fruit attributes under evaluation.

The aim of this study was to evaluate in vitro antifungal activity of Aloe vera gel on mycelial growth of Mycosphaerella fijiensis. Poisoning technique was used in PDA growth medium to for determine antifungal activity of gel. The design used was completely random, with seven treatments and three repetitions. In treatments, it was used a commercial fungicide (propiconazole), 250 ppm and 500 ppm; a commercial biofungicide (Trichoderma sp.) at 500 ppm and 1000 ppm; both products were used as chemical and biological control, respectively; Aloe vera gel 500 ppm and 1000 ppm; and an absolute control. significant differences were detected in treatments (ANOVA), Tukey test showed that all treatments registered significant difference (p ≤ 0.05) with respect to absolute control. Propiconazole had the highest inhibition Percentage of mycelium (73.10%), The Tukey test and inhibition percentage of mycelium demonstrated similar values in the control of the fungus growth in the 30 days of the inoculation, in the Aloe vera gel treatments and the T6 Trichoderma sp. The results suggest that Aloe vera could be a suitable biofungicide to control Mycosphaerella fijiensis, causative agent of black Sigatoka.

El objetivo de este trabajo fue evaluar a nivel in vitro la actividad antifúngica del gel de Aloe vera sobre el crecimiento micelial de Mycosphaerella fijiensis. Se utilizó la técnica de envenenamiento en el medio de cultivo PDA para determinar la actividad antifúngica del gel. El diseño utilizado fue completamente al azar, con siete tratamientos y tres repeticiones. En los tratamientos se utilizó un fungicida químico comercial (propiconazol), a 250 ppm y 500 ppm; un biofungicida comercial (Trichoderma sp.) a 500 ppm y 1000 ppm; ambos productos se usaron como testigo químico y biológico, respectivamente; el gel de Aloe vera a 500 ppm y 1000 ppm; y un testigo absoluto. Se determinó diferencias significativas entre los tratamientos (ANOVA), El test de Tukey demostró que todos los tratamientos registraron diferencia significativa (p ≤ 0,05) con respecto al testigo absoluto. El propiconazol presentó el mayor porcentaje de inhibición del micelio (73,10%); el test de Tukey y el porcentaje de inhibición del micelio presentaron valores similares en el control del crecimiento del hongo a los 30 días de inoculación, en los tratamientos gel de Aloe vera y el T6 de Trichoderma sp. Los resultados sugieren que el Aloe vera podría ser un adecuado biofungicida para el control de Mycosphaerella fijiensis, agente causal de la Sigatoka negra.

Resumo: O objetivo deste trabalho foi avaliar o crescimento e a produção de bananeiras com resistência à sigatoka-negra, em comparação ao desempenho de cultivares tradicionais suscetíveis à doença. Vinte cultivares foram plantadas no planalto Jaguaribe-Apodi, no Nordeste do Brasil: 15 com resistência à sigatoka-negra, a saber, Pacovan Ken, PV42-68, BRS Vitória, BRS Japira, BRS Preciosa, BRS Garantida, Thap Maeo, BRS Tropical, BRS Platina, BRS Maravilha, FHIA 02, FHIA 18, Galil 18, Caipira e Buccaneer; e cinco suscetíveis à doença, a saber, Williams, Grande Naine, Pacovan, Prata Anã e Maçã. O crescimento e a produção de cachos das bananeiras foram avaliados durante três ciclos sucessivos. 'BRS Tropical' e 'Caipira' podem substituir 'Maçã', que é bastante suscetível à murcha de Fusarium. As cultivares BRS Maravilha, BRS Platina, FHIA 02, FHIA 18 e Galil 18 apresentam porte adequado e alto potencial de rendimento, sendo alternativas ao tradicional subgrupo Prata. Já a cultivar Buccaneer é alternativa às cultivares suscetíveis do subgrupo Cavendish e pode ser explorada em agrossistema irrigado.

Abstract: The objective of this work was to evaluate the growth and the production of banana plants with resistance to black leaf streak disease (BLSD), in comparison with the performance of traditional cultivars susceptible to the disease. Twenty cultivars were planted at the Jaguaribe-Apodi plateau, in Northeastern Brazil: 15 with resistance to BLSD, namely Pacovan Ken, PV42-68, BRS Vitória, BRS Japira, BRS Preciosa, BRS Garantida, Thap Maeo, BRS Tropical, BRS Platina, BRS Maravilha, FHIA 02, FHIA 18, Galil 18, Caipira, and Buccaneer; and five susceptible to the disease, namely Williams, Grande Naine, Pacovan, Prata Anã, and Maçã. Banana growth and production of bunches was evaluated during three successive cycles. 'BRS Tropical' and 'Caipira' can replace 'Maçã', which is very susceptible to Fusarium wilt. The BRS Maravilha, BRS Platina, FHIA 02, FHIA 18, and Galil 18 cultivars show adequate height and high yield potential, being alternatives to the traditional Prata subgroup. The Buccaneer cultivar is an alternative to the susceptible cultivars of the Cavendish subgroup and can be explored in an irrigated agrosystem.

RESUMO Mycosphaerella fijiensis M. Moleret é um dos agentes causadores do “complexo Sigatoka”, o qual é a doença mais destrutiva na cultura da banana e do plátano. No presente trabalho, foi modelada espacialmente, mediante técnicas geoestadisticas, a folha mais jovem manchada (FMJM) como a variável biológica indicadora da severidade da doença na cultura, com o objetivo de determinar a sua estrutura e categoria de dependência espacial. A FMJM foi avaliada nas semanas 43, 45, 46 e 47 de 2005, sobre 71 plantas de bananeira cultivar Gran Enano com emissão recente da inflorescência. Demarcou-se, no campo, uma malha irregular, com uma distância mínima entre pares de plantas de 21 m e uma distância máxima de 1077 m, numa fazenda, localizada no Município de Carepa (Antioquia), região de floresta úmida tropical (fu-T). A variável apresentou um comportamento anisotrópico para as semanas 45, 46 e 47, foi descrito a partir de um modelo Gaussiano em cada uma das semanas, com uma gama de dependência espacial decrescente de 673.25, 345.53 y 296.36 m, respectivamente, o que diverge dos modelos reportados em outras pesquisas, em patossistemas similares. Os modelos que se ajustaram para as semanas 45 e 47, mostraram forte dependência espacial; o modelo da semana 46, moderada dependência espacial e o modelo da semana 43, sem dependência espacial.

RESUMEN Mycosphaerella fijiensis M. Morelet, es uno de los agentes causales del “complejo Sigatoka”, el cual, es la enfermedad más destructiva en los cultivos de banano y plátano. En el presente trabajo, se modeló espacialmente mediante técnicas geoestatísticas, la hoja más joven manchada (HMJM), como variable biológica indicadora del estado de severidad de la enfermedad en la plantación, con el objetivo de determinar su estructura y categoría de dependencia espacial. La HMJM se evaluó en las semanas 43, 45, 46 y 47 de 2005, em 71 plantas de banano cv. Gran Enano con emisión reciente de su inflorescencia, ubicadas en las intersecciones de una malla irregular, con una distancia mínima entre pares de plantas de 21 m y una distancia máxima de 1077 m, en una finca bananera situada en el municipio de Carepa (Antioquia), zona de vida bosque húmedo tropical (bh-T). La variable presentó un comportamiento anisotrópico para las semanas 45, 46 y 47; éste, se describió a partir de un modelo gaussiano en cada una de las semanas, con un rango de dependencia espacial decreciente de 673.25, 345.53 y 296.36 m, respectivamente, el cual diverge de los modelos reportados en otras investigaciones en patosistemas similares. Los modelos que se ajustaron para las semanas 45 y 47, evidenciaron fuerte dependencia espacial; el modelo de la semana 46, moderada dependencia espacial y el modelo de la semana 43, nula dependencia espacial.

The aim of this research was to determine resistance reaction of 14 Musa genotypes against Mycosphaerella fijensis, causal agent of Black Sigatoka disease. Two experiments were conducted in laboratory and shadehause at Pichilingue research Station from the National Institute of Agricultural Research (INIAP), Ecuador. Genotypes considered were: Orito (AA), Guineo de jardín, Williams, Filipino, Gross Mitchel, Mulato and Morado, (AAA); Limeño, Maqueño, Dominico, Dominico-Hartón, Dominico gigante, Dominico negro and Barraganete from the AAB genome. Two inoculation methods were used to asses’ resistance: a) in vitro inoculation over leaf fragments with a conidial suspension, and b) inoculation of eight weeks old seedlings with a mycelial suspension of the fungus. In the first case, the incubation period (IP) and the number of lesions at 14 and 20 days after inoculation (DDI) were measured. For in vitro trial, the incubation period (IP) and the number of leaf lesions 14 and 20 days after inoculation (DDI) were measured, and for seedlings, PI, period of symptoms evolution (TES) and time for disease development (TDE) were recorded. Statistically significant (p ≤ 0.05) differences were found for all variables. Cultivars Orito (AA) and Limeño (AAB) qualify as resistant while all the others were susceptible, though response to inoculation within the latter group showed a range of variability.

El objetivo de la investigación fue determinar la reacción de 14 genotipos de musáceas frente a Mycosphaerella fijensis, agente causal de la Sigatoka negra. Se condujeron dos experimentos en el Departamento de Protección Vegetal de la Estación Experimental Pichilingue del Instituto Nacional de Investigaciones Agropecuarias (INIAP), Ecuador. Los genotipos evaluados fueron: banano Orito (AA), Guineo de jardín, Williams, Filipino, Gros Michel, Mulato y Morado, del genoma (AAA), y los plátanos Limeño, Maqueño, Dominico, Dominico-Hartón, Dominico gigante, Dominico negro y Barraganete, del genoma AAB. Se usaron dos métodos de inoculación: a) in vitro sobre fragmentos de hoja con una suspensión de conidios y b) inoculación de plántulas de ocho semanas de edad con una suspensión micelial. En el primer caso se midió el periodo de incubación (PI) y el número de lesiones a los 14 y 20 días después de la inoculación (DDI). En invernadero, se registró el PI, tiempo de evolución de síntomas (TES) y tiempo de desarrollo de la enfermedad (TDE). Se determinaron diferencias estadísticas significativas (p ≤ 0,05) para todas las variables evaluadas; los cultivares Orito (AA) y Limeño (AAB) calificaron como resistentes, mientras que todos los demás fueron susceptibles, aunque mostraron un rango de variabilidad en la respuesta a las inoculaciones.

Nowadays, it is highly necessary to fnd more and safer agrochemicals. In this sense, micromycetes are an important source of natural products which could be used to control plant diseases. Therefore with the aims to contribute in this searching of natural products with antimicrobial applications, a total of 49 fungal strains were isolated from the Yucatan Peninsula. These fungi were cultured in fermented rice, their respective organic extracts macerated in ethyl acetate (EAE) and methanol (ME) were obtained and tested against five fungal pathogens of agricultural importance. These included Alternaria chrysanthemi, Colletotrichum gloeosporioides, Mycosphaerella fijiensis, and the bacteria Erwinia carotovora and Xanthomonas campestris using microdilution assays. The 69% of fungal extracts showed antifungal or antibacterial (2000 and 200 µg/mL, respectively) against at least one of the tested target. Strains Penicillium sp. OSE-61, Fusarium sp. OH2-30, Hypocrea lixii OSN-37 and Rhizoctonia solani OSE-73 showed activity against at least three of the five study pathogens. The most active EAE were partitioned, and its low (A), medium (B) polarity and precipitated (C) were obtained and assessed. The fraction A from Fusarium KS-15 displayed the lowest Minimum Inhibitory Concentration (MIC ≤25 µg/mL) and bactericide effect on X. campestris; fraction B of Penicillium sp. OSE-61 was relatively greater than the previous on A. chrysanthemi (MIC ≤500 µg/mL). Last fraction also exhibited good inhibitory effect on C. gloeosporioides. Finally, fraction B of H. lixii OSN-37 displayed promissory antifungal effect on C. gloeosporioides y M. fijiensis (MIC = 1000 µg/mL). This research contributes to enrich the limited knowledge on the biological activity of native anamorphic fungi of the sinkholes of Yucatan and its potential use in biotechnological applications in agriculture.

En la actualidad, es altamente necesario encontrar nuevos y más seguros productos agroquímicos. En este sentido, los micromicetos son una fuente importante de productos naturales los cuales pueden ser usados en el control de enfermedades vegetales. Con el objetivo de contribuir a la búsqueda de productos con aplicaciones antimicrobianas, un total de 49 cepas fúngicas fueron aisladas de dos cenotes de la península de Yucatán. Estas cepas se cultivaron en arroz fermentado, se obtuvieron sus respectivos extractos orgánicos macerados en acetato de etilo (EAE) y metanol (EM) y se evaluaron contra cinco fitopatógenos de importancia agrícola. Estos patógenos incluyeron a los hongos Alternaria chrysanthemi, Colletotrichum gloeosporioides, Mycosphaerella fijiensis y las bacterias Erwinia carotovora y Xanthomonas campestris, utilizando el bioensayo en microdilución. El 69% de los extractos fúngicos evaluados mostraron actividad antifúngica y/o antibacteriana contra al menos uno de los patógenos evaluados a concentraciones de 2000 y 200 µg/mL, respectivamente. Las cepas de Penicillium sp. OSE-61, Fusarium sp. OH2-30, Hypocrea lixii OSN-37 y Rhizoctonia solani OSE-73 mostraron actividad contra al menos tres de los fitopatógenos en estudio. Los extractos de EAE más promisorios fueron particionados obteniendo tres fracciones de baja (A), media (B) polaridad y un precipitado (C), los cuales fueron evaluados contra los patógenos estudiados. La fracción A de Fusarium KS-15 fue la más efectiva presentando la más baja Concentración Mínima Inhibitoria (MIC ≤25 µg/mL) y efecto bactericida contra X. campestris. La fracción B de Penicillium sp. OSE-61 contra A. chrysanthemi fue relativamente mayor (MIC ≤500 µg/mL); mientras la fracción B de H. lixii OSN-37 mostró efecto antifúngico contra C. gloeosporioides y M. fujiensis (MIC = 1000 µg/mL). Esta investigación contribuye a enriquecer el conocimiento sobre la actividad biológica de hongos anamórficos nativos de los cenotes de Yucatán y su potencial uso en aplicaciones biotecnológicas en la agricultura.

Evidencias negativas del Cambio Climático, de elevada trascendencia para el futuro productivo de la esfera agrícola y la necesidad de una soberanía y seguridad alimentaria, imponen desarrollar investigaciones para conocer el comportamiento fenológico de especies vegetales y sus plagas; fundamentalmente las de relevancia económica. El objetivo del trabajo consiste en interpretar el comportamiento epidemiológico de la enfermedad Sigatoka negra (Mycosphaerella fijiensis Morelet) en bananos para los años 2020 y 2025 bajo efectos del cambio climático en Ciego de Ávila. Se confeccionaron escenarios bioclimáticos utilizando datos diarios de temperatura máxima, temperatura mínima y el acumulado de precipitación de 14 días generados por el Modelo Climático Regional “PRECIS CARIBE” con condiciones de frontera del modelo global ECHAM-4 para proyecciones climáticas futuras bajo escenario de emisiones A2 y B2. Se obtuvieron indicadores fundamentales de valoración de esta patología: la “Suma de Velocidades” y el “Estado de Evolución” de 4 hojas. Los resultados muestran Sumas de Velocidades por encima de 11000 unidades termo-fisiológicas, así como un continuo y progresivo incremento del “Estado de Evolución” con valores superiores a 500 unidades durante todos los años analizados. Se infiere se produzca un incremento en el número de tratamientos y el costo fitosanitario, lo que supone la necesidad de trazar medidas de manejo integrado que incluyan principios agroecológicos; así como la búsqueda de variedades resistentes para sustitución de las susceptibles a la enfermedad que se emplean en la actualidad y consolidar la adaptación al cambio climático y la resiliencia en este agroecosistema.

The negative evidence of climate change of high importance for the future agricultural production and the need of food sovereignty and security, impose to develop research to predict the phenology of plants and their pests, mainly those of economic importance. The aim of this work is to interpret the epidemiological behavior of the black Sigatoka disease (Mycosphaerella fijiensis Morelet) in banana for the years 2020 and 2025 under the effects of climate change in Ciego de Avila. There were made bioclimatic scenarios using daily data of maximum temperature, minimum temperature and accumulated rainfall of 14 days generated by the Regional Climatic Model "PRECIS Caribbean" with boundary conditions of the global model ECHAM - 4 for future climate projections under scenarios of emission A2 and B2. The key indicators of this disease: "Sum of Speed " and the "Evolution state" of 4 leaves were obtained. The results show Sums speeds above 11000 thermo-physiological units, as well as a continuous and progressive increase in the "Evolution State" with values above 500 units during the analyzed years. We infers will occur an increase in the number of treatments and the plant protection cost, which implies the need to draw integrated management measures that include agro-ecological principles, search for resistant varieties to replace those susceptible to the disease that are currently used and strengthen the climate change adaptation and the resilience in the agricultural ecosystem.

Abstract: Controlling Mycosphaerella fijiensis increasingly requires the use of greater amounts of fungicides due to the resistance this pathogen has developed. A phenotypic characterization of M. fijiensis isolates in relation to their sensitivity to fungicides pyraclostrobin, epoxiconazole and tridemorph was carried out, with the intention of complementing existing methods of resistance monitoring. From symptomatic leaf tissue gathered from 12 banana farms in Colombia in 2013 and 2014, monosporic isolates were obtained and their population sensitivity and individual sensitivity were measured. This sensitivity was then compared with phenotypic traits expressed by each isolate. Results indicated that the traits associated with a greater sensitivity to pyraclostrobin were expressed in a greater number of individuals; in addition, the expression of these same features was observed as response to epoxiconazole. For tridemorph, an apparent shared domain was observed among individuals with traits associated to low and high sensitivities. A phenotypic characterization would help find if there are more or fewer individuals tolerant to an active ingredient and to define the time most suitable to apply this active ingredient without increasing the selection pressure on these individuals.

Resumen: El control de Micosphaerella fijiensis, requiere cada vez la aplicación de una mayor cantidad de fungicidas debido a la resistencia que este patógeno ha desarrollado. Se realizó una caracterización fenotípica de aislamientos de M. fijiensis en relación a su sensibilidad a los fungicidas piraclostrobin, epoxiconazol y tridemorf esperando complementar los métodos actuales de monitoreo de resistencia. A partir de tejido foliar sintomático recolectado desde 12 fincas bananeras de Colombia durante los años 2013 y 2014, se obtuvo aislamientos monospóricos a los que se les cuantificó la sensibilidad poblacional e individual. Posteriormente esta sensibilidad se comparó con los rasgos fenotípicos que cada aislamiento expresó. Los resultados indicaron que los rasgos asociados con una mayor sensibilidad a piraclostrobin se expresaron en un mayor número de individuos, además se observó la expresión de estos mismos rasgos como respuesta a epoxiconazol. Para tridemorf se observó un aparente dominio compartido entre individuos con rasgos asociados a baja y alta sensibilidad. Una caracterización fenotípica permitiría conocer si existe un mayor o menor número de individuos tolerantes a un ingrediente activo y poder definir de esta forma el momento adecuado para aplicar este ingrediente activo sin aumentar la presión de selección sobre estos individuos.