Genome-wide identification of SUN gene family in Fragaria vesca and stresses-response analysis / 生物工程学报

SUN gene is a group of key genes regulating plant growth and development. Here, SUN gene families of strawberry were identified from the genome of the diploid Fragaria vesca, and their physicochemical properties, genes structure, evolution and genes expression were also analyzed. Our results showed that there were thirty-one FvSUN genes in F. vesca and the FvSUNs encoded proteins were classified into seven groups, and the members in the same group showed high similarity in gene structures and conservative motifs. The electronic subcellular localization of FvSUNs was mainly in the nucleus. Collinearity analysis showed that the members of FvSUN gene family were mainly expanded by segmental duplication in F. vesca, and Arabidopsis and F. vesca shared twenty-three pairs of orthologous SUN genes. According to the expression pattern in different tissues shown by the transcriptome data of F. vesca, the FvSUNs gene can be divided into three types: (1) expressed in nearly all tissues, (2) hardly expressed in any tissues, and (3) expressed in special tissues. The gene expression pattern of FvSUNs was further verified by quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, the seedlings of F. vesca were treated by different abiotic stresses, and the expression level of 31 FvSUNs genes were assayed by qRT-PCR. The expression of most of the tested genes was induced by cold, high salt or drought stress. Our studies may facilitate revealing the biological function and molecular mechanism of SUN genes in strawberry.

Ecological strawberry production: promoting crop vitality with high-dynamized dilutions

The Strawberry (Fragaria× ananassaDuch.) is the world's most important berry. Around 9.2 million tonnes of strawberries were produced worldwide in 2021 over approximately 395,844 hectares distributed across almost all continents. However, industrial farming approaches, which include the application of high volumes of pesticides, have placed the fruit on the list of foods most contaminated by pesticide residues. Such management negatively affects food security and environmental sustainability. Agroecology is proposed as a holistic alternative tosolve this problem, and within this, some practices associated with homeopathy and biodynamic farming involve the application of high-dynamized dilutions as alternatives to chemical pesticides. Research indicates that the use of high-dynamized dilutions holds the potential to promote crop vitality through building natural equilibrium and resilience of agricultural systems. The objective of this research was to explore the extent to which high-dynamized dilutions can increase the sustainability of commercial strawberry production as well as understand the challenges and benefits of using high-dynamized dilutions in agriculture. To do this, natural and social science methods are combined in a multidisciplinary approach that was developed simultaneously in Brazil and the UK. Results of controlled trials demonstrated that the use of high-dynamized dilutions of Phosphorus12CH, Sulphur12 CH, and Kali Carbonicum12CH positively influenced crop production, pest disease levels, and plant vigor in strawberry plants.In addition, data collected from a web surveyand interviews with farmers, researchers,and advisors who work with homeopathy, evidenced the role of homeopathy and biodynamic farming as transformative tools regarding ecological awareness and ecological education, helping to advance the concept of the agriculture organism and subtle aspects of life into agricultural research and society.

Análise microbiológica de morangos frescos comercializados em Goiânia, Goiás / Microbiological analysis of fresh strawberries comercialized in Goiânia, Goiás

Objetivo: O consumo de alimentos contaminados por microrganismos patogênicos pode levar a quadros de doenças transmitidas por alimentos. O presente estudo objetivou realizar uma análise microbiológica de morangos frescos (Fragaria vesca) comercializados em Goiânia, Goiás, pesquisando a presença de Escherichia coli e Salmonella spp., em consonância com a RDC nº 12, de 02 de janeiro de 2001. Métodos: Foram analisadas 51 amostras de morangos frescos in natura no Laboratório Clínico da PUC Goiás, sendo 25 amostras oriundas de supermercados e 26 de comércio livre/rua, entre agosto/2019 e dezembro/2019, em diversos bairros das regiões Norte, Noroeste, Sul e Central do município de Goiânia, Goiás. Foram feitas culturas bacterianas nos ágares Eosin Methylene Blue e Salmonella-Shigella, e identificados os isolados por provas bioquímicas clássicas. Como controle de qualidade, a cada bateria de experimentos, duas cepas bacterianas conhecidas, uma Salmonella spp. (Programa Nacional de Controle de Qualidade/PNCQ) e uma E. coli ATCC 25923, foram utilizadas. Resultados: Das 51 amostras analisadas, 5,9% (3/51) apresentaram positividade para o crescimento de E. coli, sendo estas amostras adquiridas no comércio livre/rua. Foi observada ausência de Salmonella spp. Conclusão: A grande maioria (94,1%) das amostras analisadas nesta pesquisa negativaram em relação à presença de E. coli e 100% negativaram para a presença de Salmonella spp., demonstrando que independente de adquiridos em comércio livre/rua ou em supermercados, os morangos encontravam-se microbiologicamente seguros para o consumo, de acordo com a legislação brasileira vigente.

Objective: The consumption of food contaminated by pathogenic microorganisms can cause Foodborne Diseases. The present study aimed to perform a microbiological analysis of fresh strawberries (Fragaria vesca) marketed in Goiânia, Goiás, researching the presence of Escherichia coli and Salmonella spp., in line with RDC No. 12, of January 2, 2001. Methods: They have analyzed 51 samples of fresh strawberries in natura at the Clinical Laboratory of PUC Goiás, 25 samples from supermarkets and 26 from free trade/street, between August/2019 and December/2019, in several neighborhoods in the North, Northwest, South, and Central regions county of Goiânia, Goiás. Bacterial cultures cultivated on Eosin Methylene Blue and Salmonella-Shigella agar, and identification of the isolates by standard biochemical tests. As a quality control, in each battery of experiments, two known bacterial strains, one Salmonella spp. (National Quality Control Program/PNCQ) and an E. coli ATCC 25923 was used. Results: Of the 51 samples analyzed, 5.9% (3/51) were positive for the growth of E. coli, these samples were acquired in free/street commerce. Absence of Salmonella spp. Conclusion: The majority (94.1%) of the samples analyzed in this research were negative concerning the presence of E. coli, and 100% were negative for the presence of Salmonella spp., demonstrating that independent of being acquired in free trade/street or supermarkets, the strawberries analyzed were microbiologically safe for consumption, following the current Brazilian legislation.

Biosynthesis of spherical selenium nanoparticles with halophilic Bacillus subtilis subspecies stercoris strain XP for inhibition of strawberry pathogens / 生物工程学报

Biosynthesis of nanomaterials has attracted much attention for its excellent characteristics such as low energy consumption, high safety, and environmental friendliness. As we all know, the toxic selenite can be transformed into higher-value nanomaterials by using bacteria. In this study, nano-selenium was synthesized by halophilic Bacillus subtilis subspecies stercoris strain XP in LB medium supplemented with selenite (electron acceptor). The physicochemical characteristics of nano-selenium were analyzed by scanning electron microscope (SEM), X-ray energy dispersive spectral analysis (EDAX), X-ray diffraction (XRD), and fourier transform infrared spectroscopy (FTIR). Meanwhile, the antifungal activity of nano-selenium to strawberry pathogens (fusarium wilt, erythema, and purple spot fungi) was determined. The products from reduction of selenite by strain XP was amorphous spherical selenium nanoparticles (SeNPs) with a diameter range of 135-165 nm. The production of SeNPs was positively correlated with time (0-48 h) and no changes were observed on cell morphology. Selenium was dominant in the surface of SeNPs where the organic elements (C, O, N, and S) existed at the same time. SeNPs were coated with biomolecules containing functional groups (such as -OH, C=O, N-H, and C-H) which were associated with the stability and bioactivity of particles. Although the highest concentration of SeNPs had significant (P<0.05) inhibitory effects on three strains of strawberry pathogens, antifungal activity to erythema and fusarium wilt pathogenic fungi was higher than that to purple spot pathogenic fungi from strawberry. In conclusion, strain XP not only has strong tolerance to high salt stress, but can be also used to synthesize biological SeNPs with good stability and biological activity. Thus, the strain XP has bright perspectives and great potential advantage in pathogens control and green selenium-rich strawberry planting as well as other fields.

Cloning and Characterization of 5-enopy ruvylshikimate-3-phosphate Synthase from Fragaria vesca

Abstract To discover and isolate a glyphosate-resistant gene from Fragaria vesca through gene mining. An open reading frame (ORF) of 1563 bp encoding EPSPSwas amplified from Fragaria vesca (FvEPSPS). FvEPSPS (Genebank: XP004306932.1) encodes a polypeptide of 520 amino acids and it has hightly homologous with EPSPS from other plants. qRT-PCR analysis showed that the FvEPSPS was expressed extensively in all tissues including leaves, roots and stems, with higher expression in leaves. Furthermore, transgenic Arabidopsis Thaliana exhibited 10 mM glyphosate to resistance. Therefore, this research offers a new glyphosate-resistant gene for development of transgenic crops.

Micorrhizal biotechnology as an alternative to potentialize the strawberry quality / Biotecnologia micorrízica como alternativa para potencializar a qualidade do morangueiro

The need to develop and use biotechnology tools to improve management and nutritional techniques in strawberry cultivation are increasing. Based on this, the objective of this study was to test if the mycorrhizal inoculation changes the agronomic and qualitative performance of strawberry fruits. The strawberry daughters plants used were of the cultivar Camarosa. The study was carried out in an agricultural greenhouse, Horticulture Sector of the Faculty of Agronomy and Veterinary Medicine (FAMV) of UPF, in the city of Passo Fundo, Rio Grande do Sul (RS), Brazil. The experiment was developed and maintained from June to December 2015. The treatments consisted of five inoculum: T1 = no inoculum (control); T2 = Acaulospora morrowiae; T3 = Rhizophagus clarus; T4 = mycorrhizal community; T5 = Claroideoglomus etunicatum. The experimental design was a randomized block with four replicates. Each plot consisted of a bag containing 6 plants spaced 0.15 mx 0.15 m. In the pits of the plants, it was applied, with the aid of syringe and water, about 70 infective propagules of the tested inocula. During the conduction of the experiment the temperature and photosynthetically active radiation (PAR) were monitored in the culture environment. It was evaluated the agronomic and qualitative performance of the fruits and the percentage of mycorrhizal colonization of the plants roots. The data were submitted to analysis of variance and the differences between means were compared by the Tukey test at 5% of probability error. The cultivar Camarosa produced more fruits in October. In September, the month before the one with the best agronomic performance, the mean temperature was 17.7 ºC. The mean PAR recorded in the growing environment was low in relation to crop requirements, throughout the growing period. Fruits produced by plants inoculated with A. morrowiae presented higher values of TSS/TTA ratio in September and October. The percentage of mycorrhizal colonization varied from 26.2% for A. morrowiae to 46.2% for R. clarus. The inoculation of arbuscular mycorrhizal fungi does not alter the production of strawberry fruits. However, when the plants are inoculated with A. morrowiae there is an improvement in the fruit flavor.

A necessidade de desenvolver e usar ferramentas biotecnológicas para melhorar o manejo e as técnicas nutricionais no cultivo do morangueiro está aumentando. Com base nisso, o objetivo desse estudo foi testar se a inoculação micorrízica altera o desempenho agronômico e qualitativo de frutos de morangueiro. As mudas de morangueiro usadas foram da cultivar Camarosa. O estudo foi realizado em estufa agrícola, no Setor de Horticultura da Faculdade de Agronomia e Medicina Veterinária (FAMV) da UPF, na cidade de Passo Fundo, Rio Grande do Sul (RS), Brasil. O experimento foi desenvolvido e mantido de junho a dezembro de 2015. Os tratamentos consistiram em cinco inóculos: T1 = sem inóculo (controle); T2 = Acaulospora morrowiae; T3 = Rhizophagus clarus; T4 = comunidade micorrízica; T5 = Claroideoglomus etunicatum. O delineamento experimental foi em blocos casualizados, com quatro repetições. Cada parcela consistiu de um saco contendo 6 plantas espaçadas de 0.15 mx 0.15 m. Na cova de plantio das plantas, foi aplicado, com auxílio de seringa e água, cerca de 70 propágulos infectivos dos inóculos testados. Durante a condução do experimento, a temperatura e a radiação fotossinteticamente ativa (PAR) foram monitoradas no ambiente de cultivo. Foi avaliado o desempenho agronômico e qualitativo dos frutos e a porcentagem de colonização micorrízica das raízes das plantas. Os dados foram submetidos à análise de variância e as diferenças entre médias foram comparadas pelo teste de Tukey, a 5% de erro de probabilidade de erro. A cultivar Camarosa produziu mais frutos em outubro. Em setembro, no mês anterior ao de melhor desempenho agronômico, a temperatura média foi de 17.7ºC. A PAR média registrada no ambiente de cultivo foi baixa em relação às necessidades da cultura durante todo o período de cultivo. Frutos produzidos por plantas inoculadas com A. morrowiae apresentaram maiores valores da relação SST/ATT em setembro e outubro. A porcentagem de colonização micorrízica variou de 26.2% para A. morrowiae a 46.2% para R. clarus. A inoculação de fungos micorrízicos arbusculares não altera a produção de frutos de morangueiro. No entanto, quando as plantas são inoculadas com A. morrowiae, há uma melhora no sabor dos frutos.

Pollination service of Nannotrigona testaceicornis stingless bees in strawberry / Serviço de polinização da abelha Nannotrigona testaceicornis no morangueiro

Strawberry presents moderate dependence on bee pollination service, and pollination is related to the production and quality of fruits. The aim of this study was to evaluate the pollination service provided by Nannotrigona testaceicornis stingless bees in strawberry. Primary flowers of cultivar San Andreas were used in a completely randomized experimental design, with twelve replicates and five types of pollination: one N. testaceicornis visit (1V); two N. testaceicornis visits (2V); three N. testaceicornis visits (3V); natural pollination (NP); self-pollination (SP). In flowers visited by N. testaceicornis, movements and visit time were observed. The following fruit characteristics were evaluated: fruit biometry, fecundation rate of achenes, postharvest fruit quality, contribution of pollination agents and mechanisms on average fruit weight. In fruit biometry, pollination service contributed only in longitudinal length, which was higher in NP and 3V, compared to SP. In the different types of pollination, the fertilization rate of achenes did not differ and showed no effect on fresh fruit weight. In post-harvest fruit quality, 1V, 3V and NP showed better results regarding degree of deformation and marketability. Nannotrigona testaceicornis stingless bees and natural pollination contributed to the average fresh weight of strawberry fruits. Nannotrigona testaceicornis stingless bees and natural pollination provided improvement in quality and added value of fruits. Nannotrigona testaceicornis stingless bees were effective strawberry pollinators.(AU)

O morangueiro apresenta dependência moderada quanto ao serviço de polinização por abelhas, e sua polinização está relacionada com a produção e a qualidade das frutas. Diante disso, o objetivo deste estudo foi avaliar o serviço de polinização da abelha Nannotrigona testaceicornis no morangueiro. Utilizaram-se flores primárias do cultivar San Andreas no delineamento experimental inteiramente casualizado, com doze repetições e cinco tipos de polinização: uma visita de N. testaceicornis (1V); duas visitas de N. testaceicornis (2V); três visitas de N. testaceicornis (3V); polinização natural (PN) e autopolinização (AP). Os movimentos e o tempo de visita nas flores foram observados nas visitas de N. testaceicornis. Nas frutas, avaliaram-se as características: biometria das frutas, taxa de fecundação dos aquênios, qualidade pós-colheita, contribuição de agentes e mecanismos de polinização na massa média das frutas. Na biometria das frutas, o serviço de polinização contribuiu no comprimento longitudinal, que se apresentou mais elevado na PN e 3V, em relação à AP. Nos diferentes tipos de polinização, a taxa de fecundação dos aquênios não diferiu e não apresentou efeito sobre a massa fresca das frutas. Na qualidadepós-colheita, 1V, 3V e PN apresentaram melhores resultados no grau de deformação e frutas comercializáveis. A abelha N. testaceicornis e a polinização natural contribuíram na massa fresca média das frutas de morangueiro. Os serviços de polinização natural e de N. testaceicornis proporcionaram melhoria na qualidade e agregação de valor das frutas. A abelha N. testaceicornis apresentou-se como polinizadora efetiva do morangueiro.(AU)

Infestation index of Drosophila suzukii (Diptera: Drosophilidae) in small fruit in southern Brazil / Índice de infestação de Drosophila suzukii (Diptera: Drosophilidae) em pequenas frutas no sul do Brasil

The spotted-wing drosophila, Drosophila suzukii Matsumura, is considered the main insect pest of small fruit in the world. Identifying susceptible hosts is essential to develop management strategies. The aim of this study was to verify the level of D. suzukii infestation in blackberry, blueberry, strawberry, cattley guava and Surinam cherry fruits cultivated in the southern region in Brazil, and to determine the infestation index (II) per fruit. The studies were carried out during two harvests (2015/16 and 2016/17) in three areas with organic cultivation of small fruit. The highest level of D. suzukii natural infestation was observed in blackberry (40 to 65% infestation), and strawberry (approximately 30% infestation) fruits. In contrast, blueberries were less preferred (< 7% infestation). For native fruit of the region (cattley guava and Surinam cherry), it was also verified infestation of the fly, demonstrating they are hosts for multiplication in the off-season periods of the other crops. In relation to II, blackberry and Surinam cherry provided a higher average number of insects per gram of fruit (≈ 1.6 adults of D. suzukii). In contrast, blueberries and cattley guava had the lowest insect ratio per gram of fruit (≈ 0.7 adults per gram). The period between late spring to mid-autumn was considered ideal for the pest occurrence in the field. The knowledge of natural infestation levels is essential for understanding the behavior of the pest in the field, which will assist in the design of management strategies.(AU)

A drosófila-da-asa-manchada, Drosophila suzukii Matsumura, é considerada o principal inseto-praga de pequenos frutos no mundo. A identificação de hospedeiros suscetíveis é essencial para o desenvolvimento de estratégias de manejo. O objetivo deste estudo foi verificar o nível de infestação de D. suzukii em frutos de amoreira-preta, mirtileiro, morangueiro, araçazeiro e pitangueira cultivados na região no sul do Brasil e determinar os índices de infestação (II) por fruto. Os estudos foram realizados durante duas safras (2015/16 e 2016/17) em três áreas com cultivo orgânico de pequenas frutas. O maior nível de infestação natural de D. suzukii foi observado em amora-preta (40 a 65% de infestação) e morango (aproximadamente 30% de infestação). Em contraste, o mirtilo foi menos preferido (< 7% de infestação). Para as frutas nativas da região (araçá e pitanga), também ocorreu infestação da mosca, demonstrando serem hospedeiros potenciais para a multiplicação da praga nos períodos de entressafras. Em relação ao II, amoras e pitangas proporcionaram um maior número médio de insetos por grama de fruto (≈ 1,6 adultos de D. suzukii). Por outro lado, mirtilos e araçás apresentaram a menor relação de insetos emergidos por gramas de frutos (≈ 0,7 adultos por grama). O período entre final da primavera até meados do outono foi considerado ideal para a ocorrência da praga no campo. O conhecimento dos níveis de infestação natural é fundamental para o entendimento do comportamento da praga no campo, o que auxiliará no delineamento de estratégias de manejo.(AU)

Estudo do comportamento da cinética de secagem de morangos utilizando modelos da transferência de massa em secador solar / Study of the behavior of drying kinetics of strawberries using models of mass transfer

O morango (Fragaria L.) é um fruto que possui várias maneiras de preparo e consumo, devido à boa aceitação das suas características organolépticas, se torna um produto muito utilizado na indústria alimentícia. O presente trabalho teve por objetivo estudar o processo de transferência de massa em morangos por meio da desidratação da fruta em secador solar. A secagem foi realizada em um protótipo de secador solar de exposição direta com coletor solar acoplado por 16 horas e foram analisados cortes para geometria cilíndrica e geometria plana. Verificou-se que a geometria plana apresentou uma maior velocidade de secagem em relação à geometria cilíndrica. Os coeficientes de difusividade encontrados tiveram uma relação diretamente proporcional à temperatura de secagem e geometria.

Atividade antifúngica in vitro e in vivo de revestimento comestível ativo contra Colletotrichum sp / In vitro e in vivo antifungal activity of active edible coating against Colletotrichum sp

A atividade antifúngica in vitro e in vivo do carvacrol disperso no revestimentos comestíveis foi avaliada contra o Colletotrichum sp.. Na elaboração do revestimento foi utilizado amido de mandioca e gelatina. A concentração de carvacrol variou de 0-0,6 g.mL-1 de solução filmogênica. O revestimento ativo mostrou-se um ótimo antifúngico no controle da proliferação do Colletotrichum sp. com concentração inibitória mínima (CIM) para o carvacrol de 3,51 μg.mL-1. O revestimento de 0,3 mg carvacrol. g-1 solução inibiu a proliferação do Colletotrichum sp. nas análises antimicrobianas in vivo realizadas em morangos. Os revestimentos ativos foram capazes de inibir o aparecimento da doença fúngica antracnose em 80 a 90 % dos morangos com dois dias de incubação de Colletotrichum sp..

Potential of endophytic fungi as biocontrol agents of Duponchelia fovealis (Zeller) (Lepidoptera: Crambidae) / Fungos endofíticos para o biocontrole de Duponchelia fovealis (Zeller) (Lepidoptera: Crambidae)

Abstract This study reports the first assessment of endophytic fungi isolated from strawberry leaves and selection of isolates for the control of Duponchelia fovealis, a new pest of strawberries. A total of 400 strawberry leaves of the cultivar 'Albion' were collected in four commercial farms. Leaves were disinfected, cut in fragments, and placed on Petri dishes containing potato dextrose agar media with tetracycline and incubated for 30 days. Following this time, 517 fungal colonies were isolated, and thirteen genera were identified: Cladosporium, Aspergillus, Nigrospora, Fusarium, Trichoderma, Chaetomium, Alternaria, Paecilomyces, Penicillium, Ulocladium, Bipolaris, Diaporthe, and Phoma. Eight isolates belonging to the genera Aspergillus, Diaporthe, Paecilomyces, and Cladosporium were selected for pathogenicity bioassays against third instar larvae of D. fovealis. Isolates of Paecilomyces induced the highest mortality rates.

Resumo Este trabalho apresenta a primeira contribuição no isolamento de fungos endofíticos de folhas de morangueiro e na seleção de isolados para controle de Duponchelia fovealis, uma nova praga do morangueiro. Foram coletadas 400 folhas da cultivar 'Albion' em quatro lavouras comerciais de morangueiro. As folhas foram desinfetadas, cortadas em fragmentos e depositadas em placas de Petri contendo Ágar Batata Dextrose como meio, em conjunto com tetraciclina e incubados durante 30 dias. Um total de 517 colônias fúngicas e treze gêneros foram isolados: Cladosporium, Aspergillus, Nigrospora, Fusarium, Trichoderma, Chaetomium, Alternaria, Paecilomyces, Penicillium, Ulocladium, Bipolaris, Diaporthe e Phoma. Oito isolados pertencentes aos gêneros Aspergillus, Diaporthe, Paecilomyces e Cladosporium foram selecionados para os bioensaios de virulência contra larvas de 3º instar de D. fovealis. Isolados de Paecilomyces causaram as maiores taxas de mortalidade.

Linking the platelet antiaggregation effect of different strawberries species with antioxidants: metabolomic and transcript profiling of polyphenols / Asociando el efecto de antiagregación plaquetaria de distintas especies de frutillas con antioxidantes: perfil metabolómico y transcriptómico de polifenoles

A comparative study of antioxidant properties, platelet antiaggregation activity and transcriptional analysis of flavonoid biosynthesis genes were performed in Fragaria x ananassa, F. vesca and F. chiloensis subsp chiloensis f. chiloensis and f. patagonica. Furthermore, differences in flavonoid content were found by UHPLC-MS. The highest free radical scavenging activity by DPPH assay was observed in F. chiloensis f. chiloensis, meanwhile, F. vesca presented the highest antioxidant capacity by FRAP. Biosynthetic flavonoids- related transcripts were higher abundant in F. x ananassa and lower in F. vesca. Additionally, all strawberry extracts showed antiaggregant effect (1 mg mL-1), but F. vesca and F. chiloensis subsp. chiloensis f. patagonica were still active at lower concentration. This study suggests that platelet antiaggregation effect of different strawberries could be due to isoflavones and flavonoids precursors in addition to anthocyanins. Results could usefully to take decisions in future breeding programs to improve the content of healthy compounds in strawberry fruits.

Se realizó un estudio comparativo de propiedades antioxidantes, actividad de antiagregacion plaquetaria, análisis transcripcional de genes de biosíntesis de flavonoides y contenido de estos en Fragaria x ananassa, F. vesca and F. chiloensis subsp chiloensis f. chiloensis and f. patagonica. La mayor actividad removedora de radicales libres por DPPH se observó en F. chiloensis f. chiloensis, mientras F. vesca presentó la mayor capacidad antioxidante mediante FRAP. Transcritos relacionados con biosíntesis de flavonoides fueron mas abundantes en F. x ananassa y menores en F. vesca. Adicionalmente, todos los extractos de frutillas mostraron efectos antiagregante (1 mg mL-1), pero F. vesca and F. chiloensis subsp. chiloensis f. patagonica fueron activos a concentraciones menores. Este estudio sugiere que efectos de antiagregación plaquetaria en distintas frutillas podría deberse a isoflavonas y precursores de flavonoides además de antocianinas. Los resultados podrían ser útiles en programas de mejoramiento genético para mejorar el contenido de compuestos saludables en frutilla.

Genetic divergence of strawberry cultivars under different managements / Divergência genética de cultivares de morango em diferentes manejos

Developing strawberry cultivars that can be grown on a large scale, it is necessary to gather desirable characteristics such as: tolerance to Tetranychus urticae, high fruit yield and wide adaptability to several cropping managements. Therefore, our objective was to study the genetic diversity among 13 strawberry cultivars under different managements and to recommend promising crosses to obtain segreganting populations with high fruit yield and T. urticae tolerance. Trial was performed under field conditions at the Centro Regional de Desenvolvimento Rural Centro Serrano of the Instituto Capixaba for Technical Assistance and Rural Extension (Incaper), Domingos Martins-ES. We evaluated strawberry cultivars Albion, Aleluia, Aromas, Camarosa, Camino Real, Campinas, Diamante, Dover, Festival, Seascape, Toyonoka, Tudla, and Ventana, cultivated in three cropping managements: open field, low tunnel and high tunnel. Experimental design was randomized complete blocks with three replications. Variables evaluated were: number of two-spotted spider mite/cm2 on the leaf (NTSSM), total number of fruits (TNF), number of commercial fruits (NCF) and fruit yield (YIE, t/ha). We applied the generalized Mahalanobis distance and Tocher's optimization method to study the genetic diversity among cultivars in each management, and the relative contribution of traits to genetic diversity was evaluated according to the criterion described by Singh (1981). For the low tunnel and high tunnel environments, the crosses Aleluia x Camarosa, Aleluia x Aromas and Aleluia x Festival are the most promising to generate segregating populations with a higher possibility to appearance transgressive individuals, while for the open field cultivation system, we recommend the cross among Aleluia x Toynoka. The variables that most contributed for genetic dissimilarity were total number of fruits, fruit yield and number of commercial fruits for the environments open field, low tunnel and high tunnel, respectively.

´Para desenvolver cultivares de morango que podem ser cultivados em larga escala é necessário reunir características desejáveis como: tolerância ao Tetranychus urticae, alta produtividade de frutos e ampla adaptabilidade a diversos sistemas de cultivo. Portanto, o objetivo do trabalho foi estuda a diversidade genética entre 13 cultivares de morango sob diferentes manejos e recomendar cruzamentos promissores para obtenção de populações segregantes com alta produtividade de frutos e tolerantes ao T. urticae. O experimento foi conduzido sob condições de campo no Centro Regional de Desenvolvimento Rural Centro Serrano do Instituto Capixaba de Assistência Técnica e Extenção Rural (Incaper), Domingos Martins-ES, no mês de outubro (primavera). Foram avaliadas as cultivares Albion, Aleluia, Aromas, Camarosa, Camino Real, Campinas, Diamante, Dover, Festival, Seascape, Toyonoka, Tudla e Ventana, cultivadas em três sistemas de cultivo: campo aberto, túnel baixo e túnel alto. O delineamento experimental utilizado foi blocos casualizados com três repetições. As variáveis avaliadas foram: número de ácaro/cm² na folha (NTSSM), número total de frutos (TNF), número de frutos comerciais (NCF) e produtividade de frutos (YIE, t/ha). Foram empregadas a distância generalizada de Mahalanobis e o método de otimização de Tocher para o estudo da diversidade genética entre os cultivares em cada manejo, e a contribuição relativa dos caracteres para a diversidade genética foi avaliada segundo o critério de Singh (1981). Para os manejos túnel baixo e túnel alto, os cruzamentos entre os cultivares Aleluia x Camarosa, Aleluia x Aromas e Aleluia x Festival são os mais promissores para gerar populações segregantes com alta possibilidade de aparecimento de indivíduos transgressivos, enquanto que para o campo aberto recomenda-se o cruzamento entre os cultivares Aleluia x Toynoka. As variáveis que mais contribuíram para a dissimilaridade genética foram o número total de frutos, produtividade e número de frutos comerciais para os ambientes campo aberto, túnel baixo e túnel alto, respectivamente.

Investigation of Scarlet Fever Outbreak in a Kindergarten

BACKGROUND: Scarlet fever is caused by a group A streptococcal (GAS) infection. On April 3, 2017, an outbreak among children in a kindergarten was reported to the local health department. An epidemiologic investigation was conducted to identify the possible transmission route of this outbreak and to recommend appropriate control measures. MATERIALS AND METHODS: A retrospective cohort study was conducted using questionnaires including age, sex, the classroom attended at a kindergarten, and date and type of symptoms developed. A case-patient is defined as a child having sore throat, fever, skin rash, or strawberry tongue with or without laboratory confirmation of GAS infection between March 28 and April 28, 2017. RESULTS: The index case-patients developed symptoms on March 28, 2017, and this outbreak persisted over a period of 16 days. The outbreak affected 21 out of 158 children (13.3%) in the kindergarten, with the mean age of 4.2 (range 3–5) years; 12 (57.1%) of them were boys. The common symptoms reported were fever (71.4%), sore throat (71.4%), reddened tonsil (57.1%), and skin rash (52.4%). The epidemiologic analysis showed that children attending one of the classrooms in the kindergarten were 14.12 times affected than the other classrooms (relative risk, 14.12; 95% confidence interval, 4.99–33.93; P 24 hours after starting appropriate antibiotic treatment, and all the children in the kindergarten were instructed to keep strict personal hygiene practices. CONCLUSION: Our results suggest that the outbreak likely affected from the index case-patients who attended to one of the classrooms in the kindergarten. This highlights the importance of immediate notification of outbreak to prevent large number of patients.

Investigation of Scarlet Fever Outbreak in a Kindergarten

BACKGROUND: Scarlet fever is caused by a group A streptococcal (GAS) infection. On April 3, 2017, an outbreak among children in a kindergarten was reported to the local health department. An epidemiologic investigation was conducted to identify the possible transmission route of this outbreak and to recommend appropriate control measures. MATERIALS AND METHODS: A retrospective cohort study was conducted using questionnaires including age, sex, the classroom attended at a kindergarten, and date and type of symptoms developed. A case-patient is defined as a child having sore throat, fever, skin rash, or strawberry tongue with or without laboratory confirmation of GAS infection between March 28 and April 28, 2017. RESULTS: The index case-patients developed symptoms on March 28, 2017, and this outbreak persisted over a period of 16 days. The outbreak affected 21 out of 158 children (13.3%) in the kindergarten, with the mean age of 4.2 (range 3–5) years; 12 (57.1%) of them were boys. The common symptoms reported were fever (71.4%), sore throat (71.4%), reddened tonsil (57.1%), and skin rash (52.4%). The epidemiologic analysis showed that children attending one of the classrooms in the kindergarten were 14.12 times affected than the other classrooms (relative risk, 14.12; 95% confidence interval, 4.99–33.93; P 24 hours after starting appropriate antibiotic treatment, and all the children in the kindergarten were instructed to keep strict personal hygiene practices. CONCLUSION: Our results suggest that the outbreak likely affected from the index case-patients who attended to one of the classrooms in the kindergarten. This highlights the importance of immediate notification of outbreak to prevent large number of patients.

Screening and Evaluation of Yeast Antagonists for Biological Control of Botrytis cinerea on Strawberry Fruits

Gray mold (Botrytis cinerea) is one of the most common diseases of strawberries (Fragaria × ananassa Duchesne) worldwide. Although many chemical fungicides are used for controlling the growth of B. cinerea, the risk of the fungus developing chemical resistance together with consumer demand for reducing the use of chemical fungicides have necessitated an alternative method to control this pathogen. Various naturally occurring microbes aggressively attack plant pathogens and benefit plants by suppressing diseases; these microbes are referred to as biocontrol agents. However, screening of potent biocontrol agents is essential for their further development and commercialization. In this study, 24 strains of yeast with antagonistic ability against gray mold were isolated, and the antifungal activity of the volatile and diffusible metabolites was evaluated. Putative mechanisms of action associated with the biocontrol capacity of yeast strains against B. cinerea were studied through in vitro and in vivo assays. The volatile organic compounds produced by the Galactomyces candidum JYC1146 could be useful in the biological control of plant pathogens and therefore are potential alternative fungicides with low environmental impact.

Antifungal Effects of Silver Phytonanoparticles from Yucca shilerifera Against Strawberry Soil-Borne Pathogens: Fusarium solani and Macrophomina phaseolina

In the present study, the characterization and properties of silver nanoparticles from Yucca shilerifera leaf extract (AgNPs) were investigated using UV–visible spectroscopic techniques, zeta potential, and dynamic light scattering. The UV–visible spectroscopic analysis showed the absorbance peaked at 460 nm, which indicated the synthesis of silver nanoparticles. The experimental results showed silver nanoparticles had Z-average diameter of 729 nm with lower stability (195.1 mV). Additionally, our dates revealed that AgNPs showed broad spectrum antagonism (p ≤ .05) against Fusarium solani (83.05%) and Macrophomina phaseolina (67.05%) when compared to the control after nine days of incubation. Finally, AgNPs from leaf extracts of Y. shilerifera may be used as an agent of biocontrol of microorganism of importance. However, further studies will be needed to fully understand the agronanotechnological potentialities of AgNPs from Yucca schidigera.

Measurement of expansin activity and plant cell wall creep by using a commercial texture analyzer

Background: Expansins play an important role in cell wall metabolism and fruit softening. Determination of expansin activity is a challenging problem since it depends on measuring cell wall properties by using ad hoc extensometers, a fact that has strongly restricted its study. Then, the objective of the work was to adapt a methodology to measure cell wall creep and expansin activity using a commercial texture meter, equipped with miniature tensile grips and an ad hoc cuvette of easy construction. Results: It was possible to measure hypocotyls acid growth and expansin activity in a reliable and reproducible way, using a commercial texture meter, common equipment found in laboratories of food science or postharvest technology. Expansin activity was detected in protein extracts from cucumber hypocotyls, tomato and strawberry fruits, and statistical differences in expansin activity were found in both fruit models at different ripening stages. Conclusions: The possibility of measuring expansin activity following this adapted protocol with a commercial texture meter could contribute to ease and increase the analysis of expansin in different systems, leading to a better understanding of the properties of these proteins under different experimental conditions.

Meristem culture and subsequent micropropagation of Chilean strawberry (Fragaria chiloensis (L) Duch. )

BACKGROUND: Vegetative propagation of Fragaria sp. is traditionally carried out using stolons. This system of propagation, in addition to being slow, can spread plant diseases, particularly serious being viral. In vitro culture of meristems and the establishment of micropropagation protocols are important tools for solving these problems. In recent years, considerable effort has been made to develop in vitro propagation of the commercial strawberry in order to produce virus-free plants of high quality. These previous results can serve as the basis for developing in vitro-based propagation technologies in the less studied species Fragaria chiloensis. RESULTS: In this context, we studied the cultivation of meristems and establishment of a micropropagation protocol for F. chiloensis. The addition of polyvinylpyrrolidone (PVP) improved the meristem regeneration efficiency of F. chiloensis accessions. Similarly, the use of 6-benzylaminopurine (BAP) in the culture media increased the average rate of multiplication to 3-6 shoots per plant. In addition, the use of 6-benzylaminopurine (BAP), had low levels (near zero) of explant losses due to oxidation. However, plant height as well as number of leaves and roots were higher in media without growth regulators, with average values of 0.5 cm, 9 leaves and 4 roots per plant. CONCLUSIONS: For the first time in Chilean strawberry, meristem culture demonstrated to be an efficient tool for eliminating virus from infected plants, giving the possibility to produce disease free propagation material. Also, the addition of PVP into the basal MS medium improved the efficiency of plant recovery from isolated meristems. Farmers can now access to high quality plant material produced by biotech tools which will improve their technological practices.

Biological parameters and fertility life table of Aphis forbesi Weed, 1889 (Hemiptera: Aphididae) on strawberry / Parâmetros biológicos e tabela de vida de fertilidade de Aphis forbesi Weed, 1889 (Hemiptera: Aphididae) em morangueiro

Abstract This study provides the first contribution of the biology and life table of Aphis forbesi Weed, 1889 (Hemiptera: Aphididae), an important strawberry pest throughout the world. This species lives in the crown and leaf petioles of the plant. It is difficulty to rear this species in laboratory due to protocooperation with ants observed only in the field. We studied the life cycle of A. forbesi on the leaves of the Albion strawberry cultivar at 25 ± 2 °C, 60 ± 10% relative humidity, and a 12-h photophase. The experiment was randomised with 100 replicates. The parameters of the fertility life table were calculated using TabVida. In the population studied, 25% and 46% had four and three instars, respectively. A mean of 1.43 nymphs per female per day was generated. The mean reproductive period was seven days and the mean longevity was 10 days. In every 11 days there is a generation of A. forbesi, where each female has the potential to generate between 6 to 9 individuals daily, increasing its population by 1.2 times. The average life cycle was 16.8 days. High viability observed in all instars and the resulting values of R0, rm and λ suggest that A. forbesi has the capacity to increase their numbers in a short period of time, while generating high populations in strawberry crops, requiring differential management.

Resumo Este trabalho apresenta a primeira contribuição ao estudo de biologia e tabela de vida de fertilidade de Aphis forbesi, Weed, 1889 (Hemiptera: Aphididae), uma importante praga de morangueiro no mundo. Esta espécie se desenvolve na coroa e pecíolo do morangueiro. O desenvolvimento desta espécie em laboratório apresentou dificuldades, possivelmente devido à protocooperação com formigas, observada em campo durante coletas. O ciclo de vida de A. forbesi foi estudado em folhas de morangueiro cultivar ‘Albion’ a 25 ± 2 °C, 60 ± 10% umidade relativa, e fotofase de 12 horas. O experimento foi inteiramente casualizado com 100 repetições. Os parâmetros da tabela de vida de fertilidade foram calculados usando o software TabVida. Na população estudada observou-se que as ninfas apresentaram três e quatro instares, sendo 46 e 25% respectivamente, dos indivíduos que completaram o ciclo de vida. Foi gerada uma média de 1,43 ninfas/ fêmea/ dia. O período reprodutivo médio foi de 7 dias e a longevidade média 10 dias. A cada 11 dias ocorre uma geração de A. forbesi onde cada fêmea tem capacidade de gerar de 6 a 9 indivíduos aumentando em 1,2 vezes a população. O ciclo de vida de A. forbesi durou em média 16,8 dias. A alta viabilidade observada em todos os estádios, e os valores de R0, rm e λ sugerem que A. forbesi tem a capacidade de aumentar seu número em um curto período de tempo, gerando altas populações no cultivo do morangueiro, exigindo manejo diferenciado.