92 research outputs found
STYLAR MOVEMENT IN Talinum Fruticosum (TALINACEAE): CONTRIBUTIONS TO THE REPRODUCTIVE SUCCESS OF THE SPECIES IN POPULATIONS FROM CENTRAL-WEST BRAZIL
In plant species, the movement of reproductive structures can be an adaptive advantage in mating system studies. This phenomenon can promote outcrossing or cause a reduction in intrafloral male-female sexual interference. Consequently, this contributes to the avoidance of self-pollination and/or delayed autonomous self-pollination. The aim of this short communication is to report the results of assessments done in two natural populations of a native species from central-west Brazil that grows spontaneously and sub-spontaneously in opening and ruderal areas of Pantanal. In this study, the movement of the stigma was recorded throughout floral anthesis, and the mating system was determined. Floral measurements such as: flower opening time, pollen viability and the period that the stigma was receptive were also reported. The formation of fruits by spontaneous self-pollination and cross-pollination reinforces the hypothesis that stylar movement in Talinum fruticosum can facilitate or hinder self-pollination in some situations
Viabilidade e longevidade de sementes de Tabebuia aurea Benth. & Hook. submetidas a diferentes métodos de armazenamento
As sementes de Tabebuia aurea (sin. Handroanthus aureus Mattos), apresentam baixas taxas metabólicas, o que favorece o seu armazenamento em condições de temperaturas negativas e quando armazenadas em temperatura ambiente, há uma progressiva queda em sua viabilidade. Portanto, o objetivo é verificar a viabilidade e longevidade das sementes de Tabebuia aurea submetidas a diferentes métodos de armazenamento. Foram utilizadas no experimento 6100 sementes. Em geladeira foram armazenadas 2400 sementes, das quais 1200 foram acondicionadas em saco plástico transparente e 1200 em saco de papel Kraft. Outras 3600 sementes foram acondicionadas em temperatura ambiente, sendo 1200 sementes em saco plástico transparente, 1200 em saco de papel Kraft e 1200 em bandeja aberta. Para cada tratamento foram utilizadas quatro repetições de 25 sementes, por 12 meses, com delineamento inteiramente casualizado. As médias de germinação, plântulas normais e índice de velocidade de germinação foram transformados em (x +1)-1/2. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey a 5%. Também foram modeladas regressões polinomiais para as variáveis estudas em função dos períodos de armazenamento das sementes. As sementes armazenadas em geladeira à 13 ºC mantiveram elevada germinação, plântulas normais e índice de velocidade de germinação durante os 360 dias de avaliação. O método indicado para o armazenamento de sementes de Tabebuia aurea é em geladeira, à 13 ºC, tanto em saco plástico quanto de papel
Multivariate and correlation network analyses in the selection of papaya cultivars in Mato Grosso, Brazil
Papaya (Carica papaya L.) is among the most widely grown fruit species in the world and have significant economic importance in Brazil. However, most of the Brazilian production is concentrated in the Northeast and Southeast regions, limiting the potential expansion of this production chain. The objective of this study was to evaluate the performance of papaya cultivars from the Solo and Formosa groups in the state of Mato Grosso, Brazil, focusing on the combination of high-yield traits, fruit quality, and consumer acceptance through canonical variable analysis. The research was conducted in Tangará da Serra, MT, Brazil, using 11 papaya cultivars (Golden, Golden-THB, Aliança, UC14, UC16, UC12, Bela-Nova, Calimosa, Rubi-Incaper-511, T2, and Tainung-1). The cultivars showed significantly different results. Overall, they met the standards required by both national and international markets in terms of fruit physical appearance. Golden-THB (Solo group) showed the highest yield, while Golden had the highest ascorbic acid and beta-carotene contents. Rubi-Incaper-511 and UC16 were the most preferred by consumers, according to the sensory analysis.Papaya (Carica papaya L.) is among the most widely grown fruit species in the world and have significant economic importance in Brazil. However, most of the Brazilian production is concentrated in the Northeast and Southeast regions, limiting the potential expansion of this production chain. The objective of this study was to evaluate the performance of papaya cultivars from the Solo and Formosa groups in the state of Mato Grosso, Brazil, focusing on the combination of high-yield traits, fruit quality, and consumer acceptance through canonical variable analysis. The research was conducted in Tangará da Serra, MT, Brazil, using 11 papaya cultivars (Golden, Golden-THB, Aliança, UC14, UC16, UC12, Bela-Nova, Calimosa, Rubi-Incaper-511, T2, and Tainung-1). The cultivars showed significantly different results. Overall, they met the standards required by both national and international markets in terms of fruit physical appearance. Golden-THB (Solo group) showed the highest yield, while Golden had the highest ascorbic acid and beta-carotene contents. Rubi-Incaper-511 and UC16 were the most preferred by consumers, according to the sensory analysis
Secondary pollen presentation and foral traits of Heliconia psittacorum
The secondary presentation of pollen consists of a foral mechanism where the presentation of pollen occurs in other foral structures in addition to the anther, in order to increase the precision of the dispersion of the pollen by the vectors. This study aims to describe the temporal dynamics of secondary pollen presentation, and morphological and morphometric characteristics in stages of pre- anthesis and anthesis in genotypes of fve natural Heliconia psittacorum populations. For the study of foral morphometry traits of length of the fower, stamen, stigma and height of flament insertion in the petal in bud and fower were measured. The foral morphology of pre-anthesis buds and fowers in anthesis, the presence or absence of characteristics such as herkogamy, region of flament insertion in the petal, region of stylar hairs, and of secondary pollen deposition were evaluated. Treatments of controlled pollinations, self-pollination, geitonogamy, cross-pollination, natural pollination and growth to pollen tube were sampled. Floral herkogamy and pollen transfer to the adhered hairs in the stylar region were clearly observed during anthesis, constituting the frst record of occurrence of secondary pollen presentation in Heliconiaceae. Pollen tube growth was inhibited in the stigmatic, style and basal regions of the pistil. Natural fruiting produced little or no fruit. The positioning of the stamens above the stigma, pollen viability and stigma receptivity during anthesis of H. psittacorum fowers may favor self-pollination. The stylar hairs observed in all H. psittacorum populations’ help in the retention of pollen grains. The low fruiting rate in controlled and natural pollinations suggest that the main propagation form of H. psittacorum in the study areas is based on asexual reproduction
Morphological and molecular characterization of native Heliconia sp. accessions of the Amazon region
Heliconias are tropical plants with ornamental potential. These plants are particularly used in the floriculture industry because of their exotic colors and shapes. Species characterization is important for the selection of genotypes for the ornamental plant market and subsequent application in studies of genetic improvement. The aim of this study was to estimate the genetic divergence of Heliconia densiflora and Heliconia psittacorum accessions based on quantitative morphological and molecular markers. The mor- phological and molecular descriptors revealed genetic variability among the accessions evaluated. The greatest genetic variability was observed among H. psittacorum accessions, whose sample number was also larger compared to H. densiflora. Morphological characterization was efficient in differentiating the two Heliconia species, especially to characteristics such as bract and inflores- cence length, postharvest durability, and flower stem diameter, which contributed most to the divergence in this study. On the other hand, molecular characterization identified one H. densiflora individual that was grouped with the H. psittacorum genotypes. The results showed that ISSR markers can differentiate closely related H. densiflora and H. psittacorum individuals. The materials evaluated can contribute to the maintenance of local genetic diversity through the germplasm bank of the local breeding program of ornamental tropical plants
COMPORTAMENTO IN VITRO DO AGENTE ETIOLÓGICO DA FUSARIOSE E AVALIAÇÃO DE MÉTODOS DE INOCULAÇÃO EM ABACAXIZEIRO
This study aimed to evaluate the in vitro behavior of the fungus Fusarium guttiform in different conditions of temperature and luminosity and determine the most efficient inoculation method for evaluating the resistance of pineapple to fusariosis. To determine the in vitro behavior, two experiments was performed, with the same design, conduction, and evaluation. It was used a completely randomized experimental design in a factorial arrangement of 3x3 (three temperatures and three light regimes), with five replications. The evaluations of inoculation methods were conducted in a completely randomized design with factorial arrangement 3x4 (methods x distance of inoculation). D leaves of pineapple, cultivar Pearl, were inoculated at two, five, eight and eleven centimeters from the base by the methods of infected toothpick, mycelium disc without injury and mycelium disc with injury on the leaf. There was no significant difference on in vitro behavior of the isolates analyzed. The indicated temperature and luminosity for the multiplication of F. guttiform were 25°C and 12 hours, respectively, since they showed significant my celial growth and increased production of reproductive structures. The indicated method for evaluation of resistance to fusariosis in pineapple was the inoculation by infected toothpick at a distance between 2 - 11 cm from the base of the leaf. It becomes necessary to perform an injury at the site to be inoculated for the infection of the pathogen F. guttiform occurs.O presente estudo objetivou avaliar o comportamento in vitro do fungo Fusarium guttiforme em condições de temperatura e luminosidade distintas e determinar o método de inoculação mais eficiente para a avaliação da resistência de abacaxizeiro à fusariose. Para a determinação do comportamento in vitro foram realizados dois experimentos utilizando para cada o delineamento inteiramente casualizado, em esquema fatorial 3x3 (três temperaturas e três regimes de luminosidade), com cinco repetições para avaliação do índice de crescimento micelial e produção de conídios. As avaliações dos métodos de inoculação foram realizadas em delineamento inteiramente casualizado, com arranjo fatorial 3x4 (métodos x distância de inoculação) a partir de folhas “D” de abacaxizeiro da cv. Pérola, inoculadas a 2, 5, 8 e 11 centímetros da base pelos métodos palito infestado com estruturas do patógeno, disco de micélio sem ferimento e disco de micélio com ferimento na folha. Não houve diferença significativa no comportamento in vitro dos isolados analisados. A temperatura e fotoperíodo recomendadas para a multiplicação de F. guttiforme foram de 25°C e 12 horas, respectivamente, por apresentar maior índice de crescimento micelial e produção conídios. O método indicado para avaliação de resistência à fusariose do abacaxizeiro por meio de inoculação foi o palito infestado com estruturas do patógeno, a uma distância de 2 a 11 cm da base da folha. Para que ocorra infecção do patógeno F. guttiforme faz-se necessário a realização de ferimento no local a ser inoculado
Características florais e polinizadores na qualidade de frutos de cultivares de maracujazeiro‑azedo
The objective of this work was to determine the floral traits of eight cultivars of sour passion fruit and identify their pollinators, as well as to evaluate the influence of natural pollination on fruit quality, in the region of Tangará da Serra, MT, Brazil. A completely randomized experimental design was carried out, with ten replicates and one flower per plot to evaluate morphometry, and with four replicates and five flowers per cultivar to determine the fruiting rate. The following parameters were evaluated: flower morphology and morphometry, flower longevity, frequency of floral visitors, natural fruiting rate, and fruit quality. Flower morphology and morphometry were compatible with pollination by large-size bees; they were also compatible with pollination by medium‑size bees for the cultivars IAC‑275‑Maravilha, IAC‑277‑Jóia, BRS SC1, BRS RC, and BRS GA1. The greatest flower longevity was observed for the IAC‑277‑Jóia, BRS GA1, BRS RC, and BRS OV1 cultivars. The frequency of bees as Xylocopa (2.0%) and Bombus (3.9%) was low, and 'BRS GA1' received the highest number of these bee visits. Natural fruiting rate was low (36.67%). Naturally pollinated fruit show physical traits compatible with those required by the market standards.O objetivo deste trabalho foi determinar as características florais de oito cultivares de maracujazeiro‑azedo e identificar seus polinizadores, bem como avaliar a influência da polinização natural na qualidade dos frutos, na região de Tangará da Serra, MT. Utilizou-se o delineamento inteiramente casualizado, com dez repetições e uma flor por parcela para avaliar a morfometria, e com quatro repetições e cinco flores por cultivar para determinar o índice de frutificação. Avaliaram-se os seguintes parâmetros: morfologia e morfometria floral, longevidade floral, frequência de visitantes florais, índice de frutificação natural e qualidade de fruto. A morfologia e a morfometria das flores foram compatíveis com a polinização por abelhas de grande porte; também foram compatíveis com a polinização por abelhas de médio porte nas cultivares IAC‑275‑Maravilha, IAC‑277‑Jóia, BRS SC1, BRS RC e BRS GA1. A maior longevidade floral foi observada nas cultivares IAC‑277‑Jóia, BRS GA1, BRS RC e BRS OV1. A frequência de abelhas como Xylocopa (2,0%) e Bombus (3,9%) foi baixa, e 'BRS GA1' recebeu o maior número de visitas destas abelhas. O índice de frutificação natural foi baixo (36,67%). Os frutos de polinização natural apresentam características físicas compatíveis com as exigidas pelo mercado consumidor
Impacts of storage on germination and development of red ginger seeds: a tropical ornamental species
Ornamental species exhibit variability in seed size, shape, color, and reserve tissue composition. These variations often affect seed germination and seedling development. Proper seed storage is essential for maintaining seed quality. Although seed quality is not improved during storage, seeds can be preserved under favorable conditions. The objective of this study was to assess the effects of storage temperature and period on the germination of Alpinia purpurata seeds. The experiment was conducted in a germinator and in a greenhouse, using a completely randomized design with four replications, in a 2x3 factorial arrangement consisting of two temperature conditions (ambient temperature at 25 °C; refrigeration temperature at 5 °C) and three storage periods [zero (control), 30, and 60 days]; each experimental unit consisted of 25 seeds. The evaluated variables were seed moisture content, percentages of germination and emergence, germination speed index, mean germination and emergence times, and seedling characteristics (shoot and root lengths and number of leaves). The results showed that the storage period negatively affected germination and the emergence and development of A. purpurata seedlings
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