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Dehydration tolerance and storage sensitivity of Campomanesia adamantium seeds
Get PDFCultivating native fruit species depends on the existence of technical and scientific information. In this context, studies on propagation are the basis for other investigations. Campomanesia adamantium is propagated by seeds, and quality seeds guarantee the formation of high-performance plants in the field. This study aimed to analyze the dehydration tolerance and storage sensitivity of Campomanesia adamantium seeds. Experiment 1 evaluated the physiological quality of seeds with moisture contents of 43, 30, 26, 23, 18, 15, and 5%. Experiment 2 determined the seed moisture content, germination, and vigor of seeds depulped and immediately stored at 16 and 25°C, for 25 and 50 days. Seed viability was not affected by dehydration up to 15% of moisture content but decreased at 5%. Drying was accompanied by reduced seed vigor and seedling mass. The germination of unstored seeds was superior to stored ones. Storage at 16°C for 25 days was promising to maintain seed viability. The seeds showed intermediate recalcitrant behavior. Dehydration below 30% reduced vigor, while 5% affected viability. Campomanesia adamantium seeds can be stored for 25 days at 16°C in permeable packaging that maintains approximately 10% of moisture, with germination higher than 60%.O cultivo de espécies frutíferas nativas depende da existência de informações técnicas e científicas, neste contexto os estudos sobre propagação são base para os demais. A propagação em Campomanesia adamantium é realizada por sementes e as sementes de qualidade garantem a formação de plantas de alto desempenho no campo. O objetivo deste trabalho foi estudar a sensibilidade à desidratação e armazenamento de sementes de Campomanesia adamantium. O experimento 1 consistiu na avaliação da qualidade fisiológica de sementes com teores de água de 43, 30, 26, 23, 18, 15 e 5%. O experimento 2 consistiu no armazenamento de sementes recém despolpadas sob temperatura de 16 e 25 °C por 25 e 50 dias, foram determinados o teor de água, germinação e vigor. A viabilidade não foi afetada pela redução do teor de água até níveis próximos a 15%. Com 5% de água a viabilidade foi perdida. A secagem foi acompanhada pela redução do vigor das sementes e da massa das plântulas formadas. As sementes não armazenadas foram superiores, em relação ao processo de germinação, às armazenadas. A temperatura de 16 °C combinada com armazenamento por 25 dias mostrou-se promissora para manutenção da viabilidade das sementes. As sementes apresentam comportamento recalcitrante intermediário. Reduções no conteúdo de água a valores inferiores a 30% comprometem o vigor enquanto que o teor de água de 5% afeta a viabilidade. O armazenamento pode ser realizado por 25 dias sob temperatura de 16 °C em embalagem permeável que mantenha o teor de água próximo de 10%, com germinação superior a 60%
Accelerated aging test in the determination of safflower seeds vigor
Get PDFIn assessing the quality of seed lots, the vigor tests are complementary to the germination test and they identify differences in the degree of deterioration of the lots. For safflower, there is little information regarding these tests. In this way, the intention of this study was to adapt the accelerated aging test methodology to assess the physiological potential of safflower seeds (Carthamus tinctorius). For this purpose, 12 seed lots were evaluated for thousand-seed weight, germination, first germination count, seedling emergence test (emergence percentage, emergence speed index, relative emergence frequency and the initial, final and mean times) and accelerated aging. For the accelerated aging test, the traditional and saline methods were used. For this, the samples were conditioned in periods of 0, 8, 16, 24, 32 and 48 hours at 42 °C. Afterwards, they were submitted to the germination test, with evaluation of normal seedlings on the 3rd day. The 12 lots were evaluated within each period, in independent experiments. The data were submitted to analysis of variance and the means were compared using the Scott-Knott clustering method at 5% probability. In the traditional accelerated aging test the periods of 16, 24, 32 and 48 hours were more efficient in differentiating the lots in vigor levels, as they stratified the lots in three classes and the time of 8 hour classified the lots in two levels of vigor. In the accelerated saline aging method the time 32 hours were more efficient since it ranked seed lots at three levels of vigor and the periods of 8, 16 and 24 hour stratified the lots in two levels. In results obtained by the principal component analysis it was verified. The variables traditional accelerated aging for 24 and 32 hours correlated with emergence in the field. Therefore, the traditional accelerated aging test at 42 °C for 24 hours are promising for evaluating the physiological quality of safflower seeds
Functional performance, nutritional status and level of physical activity of elderly
Get PDFThe elderly is a risk group for changes in health conditions and as well as in functional performance related to the decline in grip strength and reduced walking speed, which can compromise the performance of activities of daily living. Based on this, the objective was to analyze the factors associated with functional performance in the elderly. For that, a cross-sectional study was developed involving a group of 179 elderly people who received medical care at an outpatient clinic of the public health network. Muscle strength and gait speed were measured. Nutritional status was determined by Body Mass Index (BMI), calf circumference (CC), waist circumference (WC) and waist-to-hip ratio (WHR). Level of physical activity was measured by the adapted version of the Minnesota Leisure Activities Questionnaire. Low muscle strength was found in 20.7% of the elderly and slow gait in 20.1%. Increased risk of cardiovascular disease was found in 40.8% considering WC, and 35.2% by WHR. Most of the elderly had low weight and no loss of muscle mass. Loss of muscle strength was associated with sex and CC and gait speed were associated with sex, age, and presence of a partner (p < 0.05). The chance of loss of muscle strength and lower gait speed was higher in elderly women. Loss of muscle mass due to CC was associated with the chance of loss of strength, and the chance of reduced walking speed was greater among the elderly individuals aged 75 years and over.INTRODUÇÃO: Os idosos são um grupo de risco para alterações nas condições de saúde e também podem apresentar modificações no desempenho funcional relacionadas ao declínio da força de preensão e redução da velocidade de marcha, o que pode comprometer o desempenho das atividades da vida diária. OBJETIVO: Avaliar a relação entre desempenho funcional do idoso, estado nutricional e nível de atividade física. MATERIAL E MÉTODOS: Estudo transversal envolvendo um grupo de 179 idosos que receberam atendimento médico em um ambulatório da rede pública de saúde. A força muscular e a velocidade da marcha foram medidas. O estado nutricional foi determinado pelo Índice de Massa Corporal (IMC), circunferência da panturrilha (CP), circunferência da cintura (CC) e razão cintura-quadril (RCQ). O nível de atividade física foi medido pela versão adaptada do Minnesota Leisure Activities Questionnaire. RESULTADOS: Baixa força muscular foi encontrada em 20,7% dos idosos e 20,1% apresentaram marcha lenta. O risco aumentado de doença cardiovascular foi encontrado em 40,8% considerando a CC e 35,2% na RCQ. A maioria dos idosos apresentava baixo peso e sem perda de massa muscular. A perda de força muscular foi associada ao sexo e à circunferência da panturrilha e a velocidade da marcha, ao sexo, idade e presença de parceiro (p <0,05). CONCLUSÃO: O risco de perda de força muscular e menor velocidade da marcha foram maiores em mulheres idosas. A perda de massa muscular devido à circunferência da panturrilha esteve associada ao risco de perda de força, e o risco de redução da velocidade de caminhada foi maior entre os idosos acima de 75 anos
Formulações de cobre no controle da mancha aureolada e efeitos fitotóxicos em mudas de cafeeiro
No full textBacterial blight of coffee (Pseudomonas syringae pv. garcae) is an important coffee disease and can be controlled using antibiotics and copper-based compounds. However, copper-based compounds raise doubts among coffee growers regarding bacterial blight control efficiency and phytotoxic potential. In this work, coffee plants were sprayed with different copper molecules in order to study their efficiency on bacterial blight control and the phytotoxic potential. Seven copper formulations, cuprous oxide, copper oxychloride, copper nitrate, copper hydroxide 1 (water-dispersible granules) and 2 (concentrated suspension), copper sulfate 1 (complexed with gluconic acid) and 2 (Bordeaux mixture) were studied. The copper formulations efficiency was compared with the antibiotic kasugamycin, saline solution, and control. In controlled environmental conditions of temperature, relative humidity, and photoperiod, coffee seedlings were sprayed with the treatments and after 24 hours they were inoculated with Pseudomonas syringae pv. garcae suspension. Disease incidence and severity assessments were performed in a 2-day interval during a 16-day period. Phytotoxicity incidence and severity, mapping, and quantification of copper on the leaf tissue surface, dried leaves weight, and total copper leaf content were assessed 16 days after pathogen inoculation. Data were submitted to the Scott-Knott test (p < 0.05). Cuprous oxide and copper sulfate 2 proved most efficient to bacterial blight control, causing lower phytotoxicity effect, best covering, and persistence on leaf tissues. Copper nitrate and copper sulfate complexed with gluconic acid were more phytotoxicity compared to other copper formulations.A mancha aureolada (Pseudomonas syringae pv. garcae) é uma importante doença do cafeiro e pode ser controlada com antibióticos e compostos à base de cobre. Entretanto, compostos à base de cobre levantam dúvidas entre os cafeicultores em relação à sua eficiência de controle e ao seu potencial fitotóxico. Neste trabalho, mudas de café foram pulverizadas com diferentes moléculas de cobre a fim de estudar sua eficiência no controle da mancha aureolada e seu potencial fitotóxico. Foram utilizadas sete formulações de cobre, óxido cuproso, oxicloreto de cobre, nitrato de cobre, hidróxido de cobre 1 (grânulos dispersáveis em água) e 2 (suspensão concentrada), sulfato de cobre 1 (complexado com ácido glucônico) e 2 (mistura de bordeaux). A eficiência das formulações de cobre foi comparada com o antibiótico Kasugamicina, solução salina e controle. Em condições ambientais controladas, as mudas de café foram pulverizadas com os tratamentos e após 24 horas foram inoculadas com a suspensão de Pseudomonas syringae pv. garcae. As avaliações de incidência e severidade da doença foram realizadas em um intervalo de dois dias durante o período de 16 dias. A incidência e a severidade da fitotoxicidade, o mapeamento e a quantificação de cobre na superfície do tecido foliar, o peso das folhas secas e o teor total de cobre nas folhas foram avaliados 16 dias após a inoculação do patógeno. Os dados foram submetidos ao teste de Scott-Knott (p> 0,5). O óxido cuproso e o sulfato de cobre 2 mostraram-se mais eficientes no controle da mancha aureolada, causando menor efeito fitotóxico, melhor cobertura e persistência nos tecidos foliares. O Nitrato de cobre e o sulfato de cobre complexado com ácido glucônico apresentaram maior fitotoxicidade em comparação as outras formulações de cobre utilizadas
The research effort on seeds of plant species native to the brazilian flora
Get PDFThe study performed a checklist of publications on species with available seed information and identified their issues and volumes. These publications occurred during the existence of the online versions of Revista Brasileira de Sementes (Brazilian Journal of Seeds) and the Journal of Seed Science. This data survey intends to represent a foundation for other studies and contribute to the knowledge of native plant species in Brazil. The search focused on the seeds of plants native to Brazil, indicating high negligence regarding the knowledge of Brazilian biodiversity because of the total number of articles published in 33 issues of Revista Brasileira de Sementes between 2002-2012 and the Journal of Seed Science, a substitute of the former journal, from 2012 to the first semester of 2020, with 28 issues published, but only 208 studies addressing seeds of plant species native to Brazil
Detecção de \u27CA. Phytoplasma phoenicium\u27 em plantas de pervinca (Cathranthus roseus) em Uttar Pradesh, Índia
No full textCathranthus roseus also known as periwinkle, an ornamental plant contains several medicinal values, was found with the symptoms of little leaf and witches’ broom at Shahjahanpur location with the incidence of up to 8%. The phytoplasma etiology was confirmed through scanning electron microscopy examination in all the four-leaf samples. Molecular analysis through PCR with universal primer pairs P1/P6 followed by nested PCR with R16F2n/R16r2 primers yielded ~1.2kbp amplicons in all the four symptomatic leaf samples. One amplicon was eluted, purified, sequenced, and used in BLASTn searches, which showed maximum identity of periwinkle isolate with several isolates of 16SrIX group of phytoplasma. Further, phylogenic analysis and in silico RFLP confirmed the association of 16SrIX-C subgroup phytoplasma in little leaf and witches broom plants which is the first report from India.Cathranthus roseus também conhecida como pervinca, planta ornamental contém vários valores medicinais, foi encontrada com poucos sintomas de folhas e vassouras de bruxa no local de Shahjahanpur, com incidência de até 8%. A etiologia do fitoplasma foi confirmada através do exame de microscopia eletrônica de varredura. Análises moleculares adicionais por meio de PCR aninhado, análise filogênica e silco RFLP confirmaram a associação do fitoplasma do subgrupo 16SrIX-C em pequenas plantas de folhas e vassouras de bruxa, que é o primeiro relatório da Índia
Combined effect of corn in the barrier crop and plant extracts against Cowpea mild mottle virus infecting soybean [Glycine max (L.) Merr.] in the field
Get PDFCowpea mild mottle virus (CpMMV) is one of the problems that can decrease soybean production. The research was conducted on the combined effects of corn in the barrier crop with plant extracts against CpMMV infecting soybean in the field. The field data was conducted using a Completely Randomized Design. The mean of disease incidence and disease severity is measured from total plants in each replicate plot on each treatment. Planting one or two of corn lines were grown at the edge four weeks before planting soybeans. Cashew nut shell (CNS), pagoda leaf, and rhizome of ginger extracts were applied using the sprayer and applied at 24 h before virus acquisition and transmission by whiteflies. The result showed that the virus incubation period ranged from 9−38 days after transmission longer than the untreated control. Planting two corn lines at the edge with CNS extract as bioactivator on soybean was the most extended incubation period of the virus and the lowest absorbance value DAS-ELISA of 0.20. There was a 73.11 % increase in the relative inhibition level of the virus. Planting corn at the edge with CNS extract proved to be more effective than soybean monoculture with CNS extract. However, soybean monoculture with CNS extract provides a better relative inhibition level of the virus (64.32 %) than planting two rows of corn on the edge combined with ginger of rhizome extract and planting two rows of corn on the edge with pagoda leaf extract as bioactivator on a soybean plant
SAZONALIDADE, ATRIBUTOS DO SOLO E BIOMASSA RADICULAR EM AMBIENTES DE CERRADO, CERRADÃO E FLORESTA NA AMAZÔNIA OCIDENTAL
No full textThe Amazon rainforest region presents a phytophysiognomy that ranges from savannas to cerrados, all of them intimately associated to climate and soil characteristics. Evidence has been given that plant growth and development are affected by soil quality and seasonality, thus making it crucial to understand them and how they are related to each other in order to grasp the dynamics of the whole ecosystem. In this context, the goal of this research was to assess how seasonality, soil attributes, and root system biomass are related in natural cerrado, cerradão, and forest areas in southern Amazonas State, in Brazil. Soil samples were collected during dry (June/2018) and rainy (December/2018) seasons from three different layers 0.00–0.05m; 0.05–0.15m, and 0.15–0.30m deep. In each area ten sampling points were randomly chosen. Two kinds of soil samples were collected: the first using 4.0 cm height by 5.1cm internal-diameter soil sample rings; and the second were intact soil lumps. Physical and Chemical soil attributes assessed were macro-porosity (MaP), micro-porosity (MiP), total porosity (TP), soil density (SD), aggregates texture and stability (GMD and WAR), gravimetric humidity (HG), organic carbon (OC), exchangeable aluminum (Al3+), potential acidity (H+Al), sum of bases (SB), cation exchange capacity (CEC), and root biomass (RB). All data were analysed via Tukey t test and student T test to compare results between seasons and areas. Increasing vegetation density (cerrado < cerradão < forest) was followed by an increment in CEC and OC, showing the importance of these attributes to maintaining biodiversity in environments. In amazon cerrado, rainy season as well a sandier soil textures provided favourable conditions to the growth and development of plants’ root system. Soil attributes were little affected by seasonality, that had greater effect on MiP, TP, SD, and OC, leading to lesser values for these variables during rainy season.A Amazônia apresenta fitofisionomias variando desde savanas, cerrados, com domínio das florestas e intimamente associadas ao clima e ao solo. O presente trabalho teve como objetivo avaliar o efeito da sazonalidade e a dinâmica dos atributos do solo em ambientes de cerrado, cerradão e floresta na região sul da Amazônia Ocidental. Em cada área foram escolhidos aleatoriamente quatro pontos de amostragem, em seguida foram coletados anéis volumétricos e amostras com estrutura preservada em forma de torrão nas três profundidades avaliadas. As coletas foram realizadas em dois períodos do ano: seco (junho/2018) e chuvoso (dezembro/2018). Os atributos avaliados foram: pH, acidez potencial, alumínio trocável, carbono orgânico (CO), cálcio, magnésio, fósforo, potássio, macroporosidade (MaP), microporosidade (MiP), umidade gravimétrica (UG), densidade do solo (Ds), volume total de poros (Pt), textura e estabilidade dos agregados (DMG e DMP), bem como, foram quantificados a biomassa radicular nesses ambientes, os dados obtidos foram avaliados por meio de teste de t de Tukey e o t student, para avaliação entre os ambientes e entre os períodos (chuvoso e seco). O adensamento da vegetação (cerrado < cerradão < floresta) é acompanhado do aumento da capacidade de troca de cátions e da CO, logo esses dois atributos são de grande importância para manutenção da biodiversidade dentro dos ambientes. O período chuvoso propicia um ambiente favorável para melhor desenvolvimento radicular da vegetação, bem como, a textura arenosa do solo para a melhor performance do sistema radicular das plantas no cerrado amazônico. Os atributos do solo foram pouco influenciados pela sazonalidade, afetando apenas a MiP, Pt, Ds e CO, onde os mesmos apresentaram valores reduzidos no período chuvoso
Extracts and purified substances of Cabralea canjerana inhibit hatching and extracts of Schinus terebinthifolius kill juveniles of meloidogyne incognita
Get PDFNematicidal substances have been identified from plants and are potentially useful for the management of plant-parasitic nematodes. Cabralea canjerana, (Meliaceae) and Schinus terebinthifolius (Anacardiaceae) produce bioactive compounds during their secondary metabolism and little is known about the effect of such substances on plant-parasitic nematodes. In the present study, we assessed the effect of aqueous and ethanolic extracts of C. canjerana and S. terebinthifolius at 1% (m:v) and purified substances from C. canjerana (gedunin, ocotillone, cabraleadiol, a mixture of ocotillone + cabraleadiol and a mixture of shoreic acid + eichlerianic acid) on hatching and mortality of Meloidogyne incognita juveniles. Aqueous extracts of C. canjerana fruits and seeds reduced hatching by 70.3 to 95.7%. Aqueous extracts of S. terebinthifolius fruits killed 42.8 to 77.1% of juveniles. The purified substances of C. canjerana inhibited the hatching of M. incognita from 57 to 90% and did not increase the mortality of juveniles. Therefore, C. canjerana extracts and its purified substances reduce M. incognita hatching and aqueous extracts of S. terebinthifolius kill J2 of this nematode.Substâncias nematicidas foram identificadas em plantas e podem atuar no controle de nematoides fitoparasitas. Cabralea canjerana, (Meliaceae) e Schinus terebinthifolius (Anacardiaceae) produzem compostos bioativos nos seus metabolismos secundários, os quais seus efeitos são pouco conhecidos em nematoides parasitas de plantas. No presente estudo, verificou-se o efeito do extrato aquoso e etanólico de C. canjerana e S. terebinthifolius a 1% (m:v), bem como as substâncias purificadas de C. canjerana (gedunina, ocotilona, cabraleadiol, mistura dos compostos ocotilona+cabraleadiol e mistura de ácido shoreico+ácido eichleriano) na eclosão e mortalidade de juvenis de Meloidogyne incognita. Extratos aquosos de sementes e frutos de C. canjerana reduziram a eclosão de 70.3 a 95.7%. Extratos aquosos de frutos de S. terebinthifolius causaram uma mortalidade de 42.8 a 77.1% dos juvenis. As substâncias purificadas de C. canjerana inibiram a eclosão de M. incognita de 57 a 90%, porém não aumentaram a mortalidade de juvenis. Portanto, extratos de C. canjerana e suas substâncias purificadas reduzem a eclosão de M. incognita e extratos aquosos de S. terebinthifolius controlam J2 deste nematoide.
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No full textWhiteflies (Hemiptera: Aleyrodidae) are a diverse group of sap-sucking insect species that can cause severe damage in crops with global economic importance. Hops (Humulus lupulus L.) are a crop with considerable value for the brewing and pharmaceutical industries worldwide. The aim of the current study is to register whitefly species associated with this plant in Brazil. Specimens were collected from H. lupulus leaves in four different counties in Rio de Janeiro state (Cachoeiras de Macacu, Cordeiro, Nova Friburgo and Seropédica). Whiteflies belonging to nine genera and distributed in two subfamilies (Aleurodicinae and Aleyrodinae) were identified. Nine hop varieties (i.e., Brazylinsk, Cascade, Chinook, Columbus, Hallertau, Nugget, Saaz, Spalt, and Victoria) are used as host plants by these insects in Brazil. Except for Trialeurodes vaporariorum (Westwood), the other identified species were recorded in hop crops for the first time.Moscas brancas (Hemiptera: Aleyrodidae) são um grupo diverso de espécies de insetos sugadores de seiva, algumas das quais podem causar prejuízos severos em culturas de importância econômica mundial. O lúpulo (Humulus lupulus L.) é uma cultura de grande valor mundial para as indústrias de produção de cerveja e farmacêutica. Este estudo objetivou registrar as espécies de moscas brancas associadas a essa planta no Brasil. Os espécimes foram obtidos a partir de coletas de folhas de H. lupulus realizadas em quatro municípios do estado do Rio de Janeiro (Cachoeiras de Macacu, Cordeiro, Nova Friburgo e Seropédica). Identificou-se moscas brancas de nove gêneros distribuídos em duas subfamílias (Aleurodicinae e Aleyrodinae). Registra-se nove variedades de lúpulo (Brazylinsk, Cascade, Chinook, Columbus, Hallertau, Nugget, Saaz, Spalt e Victoria) como plantas hospedeiras de moscas brancas no Brasil. Com exceção de Trialeurodes vaporariorum (Westwood, 1856), os demais táxons identificados no presente estudo são pela primeira vez registrados associados ao lúpulo