The Role of Annual Flowering Plant Strips on a Melon Crop in Central Spain. Influence on Pollinators and Crop
Facilitation, Wild bees, agri-environment scheme, attractiveness, ecosystem services, interspecific competition
Planting flower strips adjacent to crops is among the habitat-management practices employed to offer alternative floral resources to pollinators. However, more information is needed to understand their potential spill-over of pollinators on nearby insect-pollinated crops. Over the course of two consecutive years, the suitability of a flower mixture of 10 herbaceous plants for pollinators was evaluated on a weekly basis, in a randomized block design of two melon plots (10 × 10 m2) with or without 1 m-wide flower strips. Floral coverage and pollinator visits to the plant species, as well as pollinator visits and the yield and quality of the crop, were assessed. Additionally, the selected mixture was tested for 1 year in a commercial field in order to ascertain how far the flower strip could influence visitors in the crop. The most suitable species for a flower strip in central Spain based on their attractiveness, floral coverage and staggered blossom were Coriandrum sativum L., Diplotaxis virgata L., Borago officinalis L. and Calendula officinalis L. The flower strip can act as either pollinator competitor or facilitator to the crop, depending on their floral coverage and/or the predominant species during the crop bloom period. The concurrence of blooming of the rewarding plant C. officinalis with the melon crop should be avoided in our area. In the commercial field, the bee visitation rate in the melon flowers decreased with the distance to the flower strip. No influence of the specific flower strip evaluated on crop productivity or quality was found.
Celeste Azpiazu, Pilar Medina, Ángeles Adán, Ismael Sánchez-Ramos, Pedro del Estal, Alberto Fereres, Elisa Viñuela
Transcriptome analysis of the fungal pathogen Rosellinia necatrix during infection of a susceptible avocado rootstock identifies potential mechanisms of pathogenesis
Persea americana, Virulence, ascomycete, effectors, white root rot
Abstract Background White root rot disease caused by Rosellinia necatrix is one of the most important threats affecting avocado productivity in tropical and subtropical climates. Control of this disease is complex and nowadays, lies in the use of physical and chemical methods, although none have proven to be fully effective. Detailed understanding of the molecular mechanisms underlying white root rot disease has the potential of aiding future developments in disease resistance and management. In this regard, this study used RNA-Seq technology to compare the transcriptomic profiles of R. necatrix during infection of susceptible avocado ‘Dusa’ roots with that obtained from the fungus cultured in rich medium. Results The transcriptomes from three biological replicates of R. necatrix colonizing avocado roots (RGA) and R. necatrix growing on potato dextrose agar media (RGPDA) were analyzed using Illumina sequencing. A total of 12,104 transcripts were obtained, among which 1937 were differentially expressed genes (DEG), 137 exclusively expressed in RGA and 160 in RGPDA. During the root infection process, genes involved in the production of fungal toxins, detoxification and transport of toxic compounds, hormone biosynthesis, gene silencing and plant cell wall degradation were overexpressed. Interestingly, 24 out of the 137 contigs expressed only during R. necatrix growth on avocado roots, were predicted as candidate effector proteins (CEP) with a probability above 60%. The PHI (Pathogen Host Interaction) database revealed that three of the R. necatrix CEP showed homology with previously annotated effectors, already proven experimentally via pathogen-host interaction. Conclusions The analysis of the full-length transcriptome of R. necatrix during the infection process is suggesting that the success of this fungus to infect roots of diverse crops might be attributed to the production of different compounds which, singly or in combination, interfere with defense or signaling mechanisms shared among distinct plant families. The transcriptome analysis of R. necatrix during the infection process provides useful information and facilitates further research to a more in -depth understanding of the biology and virulence of this emergent pathogen. In turn, this will make possible to evolve novel strategies for white root rot management in avocado.
A. Zumaquero, S. Kanematsu, H. Nakayashiki, A. Matas, E. Martínez-Ferri, A. Barceló-Muñóz, F. Pliego-Alfaro, C. López-Herrera, F. M. Cazorla, C. Pliego
Endophytic Trichoderma Species Isolated from Persea americana and Cinnamomum verum Roots Reduce Symptoms Caused by Phytophthora cinnamomi in Avocado
antagonism, biocontrol, disease incidence, root rot, soil borne
Avocado root rot caused by the oomycete Phytophthora cinnamomi is a severe disease that affects avocado production in Mexico and worldwide. The use of biological control agents such as Trichoderma species isolated from places where the disease is always present, represents an efficient alternative to reduce losses. Thus, the objective of this research was to evaluate the biocontrol ability of 10 endophytic Trichoderma spp. strains against P. cinnamomi tested both in vitro and in the greenhouse. The endophytic Trichoderma spp. were recovered from Persea americana and Cinnamomum verum roots, isolated and purified on potato–dextrose–agar medium. Ten strains were identified by phylogenetic reconstruction of the internal transcribed spacer region of rDNA sequences as T. asperellum (T-AS1, T-AS2, T-AS6, and T-AS7), T. harzianum (T-H3, T-H4, and T-H5), T. hamatum (T-A12), T. koningiopsis (T-K8 and T-K11), and P. cinnamomi (CPO-PCU). In vitro dual-culture assay, the percentage of inhibition of radial growth (PIRG) between Trichoderma spp. and P. cinnamomi strains was measured according to the Bell’s scale. PIRG results indicated that T-AS2 reached the highest value of 78.32%, and T-H5 reached the lowest value of 38.66%. In the greenhouse, the infection was evaluated according to the percentage of disease incidence. Plants with the lowest incidence of dead by avocado root rot were those whose seedlings were inoculated with T-AS2 and T-AS7, resulting in only 5% death by root rot caused by P. cinnamomi. The disease incidence of seedlings with wilt symptoms and death decreased more than 50% in the presence of Trichoderma spp. Relying on the results, we conclude that T. asperellum and T. harzianum contribute to the biocontrol of soil-borne pathogenic oomycete P. cinnamomi.
Petra Andrade-Hoyos, Hilda Victoria Silva-Rojas, Omar Romero-Arenas
The Strawberry FaWRKY1 Transcription Factor Negatively Regulates Resistance to Colletotrichum acutatum in Fruit Upon Infection
Agrobacterium transformation, Colletotrichum acutatum, Fragaria × ananassa, WRKY transcription factor, strawberry fruit defense response
Strawberry (Fragaria ×ananassa) is a major food crop worldwide, due to the flavor, aroma and health benefits of the fruit, but its productivity and quality are seriously limited by a large variety of phytopathogens, including Colletotrichum spp. So far, key factors regulating strawberry immune response remain unknown. The FaWRKY1 gene has been previously proposed as an important element mediating defense responses in strawberry to Colletotrichum acutatum. To get further insight into the functional role that FaWRKY1 plays in the defense mechanism, Agrobacterium-mediated transient transformation was used both to silence and overexpress the FaWRKY1 gene in strawberry fruits (Fragaria ×ananassa cv. Primoris), which were later analyzed upon C. acutatum inoculation. Susceptibility tests were performed after pathogen infection comparing the severity of disease between the two agroinfiltrated opposite halves of the same fruit, one half bearing a construct either for FaWRKY1 overexpression or RNAi-mediated silencing and the other half bearing the empty vector, as control. The severity of tissue damage was monitored and found to be visibly reduced at five days after pathogen inoculation in the fruit half where FaWRKY1 was transiently silenced compared to that of the opposite control half and statistical analysis corroborated a significant reduction in disease susceptibility. Contrarily, a similar level of susceptibility was found when FaWRKY1 overexpression and control fruit samples, was compared. These results unravel a negative regulatory role of FaWRKY1 in resistance to the phytopathogenic fungus C. acutatum in strawberry fruit and contrast with the previous role described for this gene in Arabidopsis as positive regulator of resistance against the bacteria Pseudomonas syringae. Based on previous results, a tentative working model for WRKY75 like genes after pathogen infection is proposed and the expression pattern of potential downstream FaWRKY1 target genes was also analyzed in strawberry fruit upon C. acutatum infection. Our results highlight that FaWRKY1 might display different function according to species, plant tissue and/or type of pathogen and underline the intricate FaWRKY1 responsive defense regulatory mechanism taking place in strawberry against this important crop pathogen.
José Javier Higuera, José Garrido-Gala, Ayman Lekhbou, Isabel Arjona-Girona, Francisco Amil-Ruiz, José A. Mercado, Fernando Pliego-Alfaro, Juan Muñoz-Blanco, Carlos J. López-Herrera, José L. Caballero
Floristic composition and similarity of 15 hectares in Central Amazon, Brazil
Amazonía Central, Diversidad, Ecología forestal, bosque denso de tierras altas, composición boscosa, similitud florística, terra firme
La región amazónica es una de las más diversas áreas del mundo. Los estudios sobre la gran diversidad de bosques tropicales generan contribuciones relevantes en la comprensión de los mecanismos que originan y apoyan tal diversidad. En el presente estudio se describe la composición de las especies y la diversidad de 15 parcelas de una hectárea en el bosque denso amazónico terra firme en Brasil, y compara la similitud florística de estas parcelas con otras nueve parcelas de una hectárea. Las 15 parcelas estudiadas fueron seleccionadas al azar, en el 2005, de parcelas permanentes en el sitio experimental de Embrapa, Estado de Amazonas. La diversidad fue analizada utilizando la riqueza de especies y el índice de Shannon, así como el índice de Similitud de Sorensen; y como método de agrupación se utilizó el promedio no ponderado por grupo (UPGMA). La prueba de Mantel se llevó a cabo para estudiar si las diferencias en la composición de especies entre los sitios podrían ser explicadas por la distancia geográfica entre ellos. En general, se identificaron 8 771 individuos, 264 especies y 51 familias de plantas. La mayoría de las especies se concentraron en pocas familias y pocas tenían un gran número de individuos. Las familias que presentaron la mayor riqueza de especies fueron: Fabaceae (Faboideae: 22spp, Mimosoideae: 22spp), Sapotaceae: 22spp, Lecythidaceae: 15 y Lauraceae: 13. Burseraceae tuvo el mayor número de individuos con un 11.8% del total. Las diez especies más abundantes fueron: Protium hebetatum (1 037 individuos), Eschweilera coriacea (471), Licania oblongifolia (310), Pouteria minima (293), Ocotea cernua (258), Scleronema micranthum (197), Eschweilera collina (176), Licania apelata (172), Naucleopsis caloneura (170) y Psidium araca (152), que representó un 36.5% de todos los individuos. Aproximadamente en el 49% de las especies se encontraron hasta diez individuos, mientras que el 13% de las especies apareció sólo una vez en todas las parcelas de muestreo, lo que demuestra una alta presencia de especies raras. La zona de estudio se encuentra en un bosque con alta diversidad de especies de árboles, con un índice de diversidad de Shannon de 4.49. El dendrograma mostró dos grupos de parcelas con baja similitud entre ellas (menos de 0.25), y entre más cercanas las parcelas, más similares en composición de especies fueron (Mantel R=0.3627, p
Kátia Emidio da Silva, Sebastião Venancio Martins, Carlos Antonio Alvares Soares Ribeiro, Nerilson Terra Santos, Celso Paulo de Azevedo, Francisca Dionizia de Almeida Matos, Ieda Leão do Amaral
Areas of natural occurrence of Melipona scutellaris Latreille, 1811 (Hymenoptera: Apidae) in the state of Bahia, Brazil
Stingless bee beekeeping, Stingless bees, abelha uruçu, abelhas sem-ferrão, distribuição, distribution, meliponicultura, uruçu bee
The bee Melipona scutellaris is considered the reared meliponine species with the largest distribution in the North and Northeast regions of Brazil, with records from the state of Rio Grande do Norte down to the state of Bahia. Considering the importance of this species in the generation of income for family agriculture and in the preservation of areas with natural vegetation, this study aimed at providing knowledge on the distribution of natural colonies of M. scutellaris in the state of Bahia. Literature information, interviews with stinglessbee beekeepers, and expeditions were conducted to confirm the natural occurrence of the species. A total of 102 municipalities showed records for M. scutellaris, whose occurrence was observed in areas ranging from sea level up to 1,200-meter height. The occurrence of this species in the state of Bahia is considered to be restricted to municipalities on the coastal area and the Chapada Diamantina with its rainforests. Geographic coordinates, elevation, climate and vegetation data were obtained, which allowed a map to be prepared for the area of occurrence in order to support conservation and management policies for the species.A abelha Melipona scutellaris é considerada a espécie criada de meliponíneo com maior distribuição no norte e nordeste do Brasil, com ocorrência registradas desde o Estado do Grande do Norte até o Estado da Bahia. Considerando a importância desta espécie na geração de renda para agricultura familiar e na manutenção de áreas com vegetação natural, este trabalho teve como objetivo conhecer a distribuição de colônias naturais de M. scutellaris no Estado da Bahia. Informações de literatura, entrevistas com meliponicultores e expedições foram realizadas para confirmar a ocorrência natural da espécie. Um total de 102 municípios apresentou registro de M. scutellaris, cuja ocorrência foi observada em áreas desde o nível do mar até 1.200 metros de altitude. A ocorrência desta espécie no Estado da Bahia é considerada como restrita a municípios da área costeira e da Chapada Diamantina, onde existem matas úmidas. Dados de coordenadas geográficas, altitude, clima e vegetação foram obtidos, possibilitando elaborar o mapa da área de ocorrência, subsidiando políticas de conservação e manejo da espécie.
Rogério M.O. Alves, Carlos A.L. Carvalho, Bruno A. Souza, Wyratan S. Santos
Anais da Academia Brasileira de Ciências
Exploratory Monitoring of the Quality and Authenticity of Commercial Honey in Ecuador
Raman spectroscopy, adulteration, chemometric, honey, infrared spectroscopy
Honey is one of the oldest sweetening foods and has economic importance, making this product attractive to adulteration with cheap sugars. This can cause a critical problem in the honey industry and a possible health risk. The present work has the aim of evaluating the authenticity of honey commercialized in two different provinces of Ecuador (Pichincha and Loja) by performing physicochemical and spectroscopic analyses. For this study 25 samples were collected from different places and markets and characterized by water, sucrose, reducing sugars and electric conductivity measurement. Also, their Raman and Infrared (IR) spectra were recorded and analysed using a Principal Component Analysis (PCA) in order to verify the quality of the honeys. In addition, a screening of several pesticides was performed in order to verify possible chemical threats to human health and honey bees. It was found that 8 samples have a deviation from the Standard established parameters. Two of them have a high difference in the content of sucrose and reducing sugars, which are located deviated from all the other samples in the PCA of the applied vibrational spectroscopy (IR/Raman), shaping two clear clusters. The results show that Raman and IR spectroscopy is appropriate techniques for the quality control of honey and correlates well with the physicochemical analyses.
Lorena Salvador, Michelle Guijarro, Daniela Rubio, Bolívar Aucatoma, Tanya Guillén, Paul Vargas Jentzsch, Valerian Ciobotă, Linda Stolker, Sonia Ulic, Luis Vásquez, Patricia Garrido, Juan Bravo, Luis Ramos Guerrero
Determination of the Volatile Profile of Lemon Peel Oils as Affected by Rootstock
citrus limon (l.), Aldehydes, GC/MS, Limonene, aroma composition, concentrations—monoterpene, sesquiterpenes
Citrus limon (L.) Burm is an important crop that grows between latitudes 30° North and 30° South, the main producers being China, the USA, Mexico, India, Brazil, and Spain. In Spain, lemon grows mainly in Mediterranean areas such as Murcia, Valencia, and Andalucía. The most cultivated varieties are “Fino” and “Verna”. In this study, five varieties of lemon, “Verna”, “Bétera”, “Eureka”, “Fino 49”, and “Fino 95” were evaluated on different rootstocks: three new Forner-Alcaide (“FA13”, “FA5”, “FA517”), Citrus macrophylla, Wester, and Citrus aurantium L. Hydrodistillation was used to obtain essential oil from fresh peels and then the volatile profile was studied by gas chromatography-mass spectrometry (GC-MS). A total of 26 volatile compounds were identified, limonene being the main one followed by β-pinene, γ-terpinene, sabinene, and α-pinene. The results revealed that Forner-Alcaide rootstocks (“FA5” > “FA517” > “FA13”) proved to be the best rootstocks for the aroma quality as they led to high volatile contents, followed by C. aurantium and C. macrophylla. Among the other varieties, the most aromatic one was “Eureka”. The whole trend was as follows (in decreasing order): “Eureka” > “Bétera” > “Fino 95” > “Verna” > “Fino 49”.
Ángel A. Carbonell-Barrachina, Marlene G. Aguilar-Hernández, Paola Sánchez-Bravo, Francisca Hernández, Joaquín J. Pastor-Pérez, Pilar Legua
Folin-Ciocalteu Reaction Alternatives for Higher Polyphenol Quantitation in Colombian Passion Fruits
Passiflora edulis Flavicarpa, Passiflora edulis Sims, and Passiflora ligularis Juss are Colombian fruits (passion fruits) of important exportation value. They act efficiently as antioxidants, antifungal, and antimicrobial compounds due to their high polyphenol content. Polyphenols can be quantified by the Folin-Ciocalteu (F-C) reaction. Food matrices, solvent polarity, and several different reacting conditions are critical for the optimum extraction and quantification of polyphenols. Chromatographic identification and quantitation are satisfactory with access to a vast number of reference standards considering the availability of abundant phenolic compounds in crude extracts. The purpose of this study was to evaluate alternatives and specific F-C reacting conditions aiming at determining the highest total phenolic content (TPC) in three Colombian Passifloras. Among optimum reacting conditions, reduced reaction time and diluted alkali conditions yielded desirable positive results highlighting lower working time and minimum reagent waste production. For higher extraction yield, acetone 70% was the best solvent to capture more phenolics from the seedless pulp of these Colombian passion fruits.
Juan C. Carmona-Hernandez, Gonzalo Taborda-Ocampo, Clara H. González-Correa
Nutrition. Foods and food supply, Food processing and manufacture
Metabolomic Markers for the Early Selection of Coffea canephora Plants with Desirable Cup Quality Traits
coffea canephora, Plant metabolomics, cup quality, early selection, metabolic marker, metabolome-wide association study (mwas)
Genetic improvement of coffee plants represents a great challenge for breeders. Conventional breeding takes a too long time for responding timely to market demands, climatic variations and new biological threads. The correlation of genetic markers with the plant phenotype and final product quality is usually poor. Additionally, the creation and use of genetically modified organisms (GMOs) are often legally restricted and rejected by customers that demand natural products. Therefore, we developed a non-targeted metabolomics approach to accelerate conventional breeding. Our main idea was to identify highly heritable metabolites in Coffea canephora seedlings, which are linked to coffee cup quality. We employed a maternal half-sibs approach to estimate the metabolites heritability in open-pollinated plants in both leaves and fruits at an early plant development stage. We evaluated the cup quality of roasted beans and correlated highly heritable metabolites with sensory quality traits of the coffee beverage. Our results provide new insights about the heritability of metabolites of C. canephora plants. Furthermore, we found strong correlations between highly heritable metabolites and sensory traits of coffee beverage. We revealed metabolites that serve as predictive metabolite markers at an early development stage of coffee plants. Informed decisions can be made on plants of six months old, compared to 3.5 to 5 years using conventional selection methods. The metabolome-wide association study (MWAS) drastically accelerates the selection of C. canephora plants with desirable characteristics and represents a novel approach for the focused breeding of crops.
Roberto Gamboa-Becerra, María Cecilia Hernández-Hernández, Óscar González-Ríos, Mirna L. Suárez-Quiroz, Eligio Gálvez-Ponce, José Juan Ordaz-Ortiz, Robert Winkler