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9. Vivipary and light quality effects on seed germination of the columnar cactus, Cereus jamacaru.

Author

Santos, Jessyca Adelle Silva, Meiado, Marcos Vinicius, and Garcia, Queila Souza

Subjects
*TROPICAL dry forests, *FRUIT seeds, *GERMINATION, *SEEDS, *SEED quality
Abstract

Vivipary is a remarkable trait in the Cactaceae family. Here, we reported a case of vivipary in Cereus jamacaru and observed which season had the highest vivipary incidence by examining the types of fruits and seeds produced during two contrasting periods in a seasonally dry tropical forest in northeastern Brazil. Additionally, because seeds of this species are positively photoblastic, a germination experiment was conducted to confirm whether seeds inside viviparous fruits (VFs) exhibited changes in light sensitivity. Seeds from VFs were then subjected to different light quality treatments, and their germination was compared with that observed in seeds from non‐viviparous fruits (NVFs). Vivipary only occurred in fruits produced at the end of the rainy season. Viviparous fruits' seeds had a higher germination percentage under far‐red light than NVFs' seeds, suggesting that vivipary may favor seed germination under canopy‐shade light and therefore provide new avenues for survival in semiarid environments. [ABSTRACT FROM AUTHOR]

Published
2024
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10. Tolerance Mitigates Gall Effects When Susceptible Plants Fail to Elicit Induced Defense.

Author

Andrade, Janete Ferreira, Calixto, Eduardo Soares, Demetrio, Guilherme Ramos, Venâncio, Henrique, Meiado, Marcos Vinicius, de Santana, Denise Garcia, Cuevas-Reyes, Pablo, de Almeida, Wanessa Rejane, and Santos, Jean Carlos

Subjects
PLANT performance, PLANT defenses, BAUHINIA, HOST plants, PLANT variation, CHEMICAL plants
Abstract

Variations in plant genotypes and phenotypes are expressed in ways that lead to the development of defensive abilities against herbivory. Induced defenses are mechanisms that affect herbivore insect preferences and performance. We evaluated the performance of resistant and susceptible phenotypes of Bauhinia brevipes (Fabaceae) against attacks by the gall-inducing insect Schizomyia macrocapillata (Diptera). We hypothesized that there is a positive relationship between resistance to S. macrocapillata and host plant performance because resistance can have a high adaptive value. We evaluated plant architecture, nutritional leaf quality, leaf fluctuating asymmetry, and reproductive capacity between phenotypes. Plant performance was evaluated at three ontogenetic stages: seed, seedling, and juvenile. Overall, there were no differences in vegetative and reproductive performance or asymmetry between the resistant and susceptible mature plants. We found no relationship between leaf nutritional quality and resistance to S. macrocapillata. Plant performance was consistent across ontogeny for both phenotypes, except for five variables. Contrary to our expectations, the susceptible plants performed equally well or better than the resistant plants, suggesting that tolerance and overcompensation to herbivory in B. brevipes may be mediated by induced defense. Our study highlights the importance of multiple layers of plant defense against herbivory, where plant tolerance acts as a secondary barrier in plants susceptible to gall-inducing insects. [ABSTRACT FROM AUTHOR]

Published
2024
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13. Traditional Uses, Phytochemistry, and Bioactivities of Mesosphaerum suaveolens (L.) Kuntze

Author

Almeida-Bezerra, José Weverton, Rodrigues, Felicidade Caroline, Lima Bezerra, José Jailson, Vieira Pinheiro, Anderson Angel, Almeida de Menezes, Saulo, Tavares, Aline Belém, Costa, Adrielle Rodrigues, Augusta de Sousa Fernandes, Priscilla, Bezerra da Silva, Viviane, Martins da Costa, José Galberto, Pereira da Cruz, Rafael, Bezerra Morais-Braga, Maria Flaviana, Melo Coutinho, Henrique Douglas, Teixeira de Albergaria, Edward, Meiado, Marcos Vinicius, Siyadatpanah, Abolghasem, Kim, Bonglee, and Morais de Oliveira, Antônio Fernando

Subjects
Article Subject
Abstract

Mesosphaerum suaveolens (L.) Kuntze is a species widely used traditionally in the treatment of ailments, such as stomach pain, hemorrhoids, cough, verminosis, ulcer, liver disease, fever, influenza, nasal congestion, and inflammation. This review aims to provide a survey of available information on seven international electronic databases (Google Scholar, Medline, ResearchGate, Web of Science, Scopus, Science Direct, and PubMed) about botanical aspects, traditional uses, phytochemistry, and biological activities of M. suaveolens. Mesosphaerum suaveolens is a tropical America native species, but it can be found in several parts of the world as a ruderal plant. The species is the most studied species of the genus Lamiaceae due its phytochemical aspect, especially regarding the chemical composition of its essential oil. Besides the essential oils, M. suaveolens is a source of numerous secondary compounds such as triterpenes, diterpenes, and phenolic compounds, which are related to its biological activities, such as allelopathic, antibacterial, antifungal, insecticidal, and larvicidal activities as described in the literature.

Published
2022
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15. Seed germination of three endangered subspecies of Discocactus Pfeiff. (Cactaceae) in response to environmental factors

Author

Nascimento, Joana Paula Bispo, Meiado, Marcos Vinicius, and Siqueira-Filho, José Alves

Subjects
temperatura, abiotic factors, caatinga, fotoblastismo, temperature, fatores abióticos, photoblastism, germinability, germinabilidade
Abstract

Temperature, light, water availability and excessive salt in the soil are among the abiotic factors that most influence the germination process in semiarid ecosystems. The aim of the present study was to determine the effect of these abiotic factors on seed germination in three subspecies of cactus: Discocactus bahiensis, D. zehntneri subsp. petr-halfarii and D. zehntneri subsp. zehntneri. Seeds were set for germination under two light conditions (12-h light/dark photoperiod and continuous darkness) and 10 temperature treatments [eight constant temperatures (10, 15, 20, 25, 30, 35, 40 and 45 °C) and two alternating temperatures (30 to 20 °C and 35 to 25 °C)]. Polyethylene Glycol (PEG) 6000 and sodium chloride (NaCl) were used to simulate water and saline stress, respectively, with the following osmotic potentials: 0.0, -0.2, -0.4, -0.6, -0.8 and -1.0 MPa. Three subspecies were positive photoblastic. The optimum temperature for germination was 25 to 35 ºC for D. bahiensis and D. zehntneri subsp. zehntneri, and 30 to 35 ºC for D. zehntneri subsp. petr-halfarii. The seeds of all three subspecies exhibited tolerance to water and saline stress, as germination was observed at potentials for up to -0.6 MPa in the PEG and NaCl solutions. Resumo: Temperatura, luz, disponibilidade de água e sal excessivo no solo estão entre os fatores abióticos que mais influenciam o processo de germinação em ecossistemas semiáridos. O objetivo do presente estudo foi determinar o efeito desses fatores abióticos sobre a germinação de sementes em três subespécies de cactos: Discocactus bahiensis, D. zehntneri subsp. petr-halfarii e D. zehntneri subsp. zehntneri. As sementes foram colocadas para germinação sob duas condições de luz (fotoperíodo de 12 horas e escuro contínuo) e 10 tratamentos de temperatura [oito temperaturas constantes (10, 15, 20, 25, 30, 35, 40 e 45 °C) e duas temperaturas alternadas (30 a 20 °C e 35 a 25 °C)]. Foram utilizados polietilenoglicol (PEG) 6000 e cloreto de sódio (NaCl) para simular o estresse hídrico e salino, respectivamente, com os seguintes potenciais osmóticos: 0,0; -0,2; -0,4; -0,6; -0,8 e -1,0 MPa. As três subespécies são fotoblásticas positivas. A temperatura ótima de germinação foi de 25 a 35 ºC para D. bahiensis e D. zehntneri subsp. zehntneri e 30 a 35 ºC para D. zehntneri subsp. petr-halfarii. As sementes das três subespécies exibiram tolerância ao estresse hídrico e salino, pois foi observada germinação em potenciais de até -0,6 MPa nas soluções de PEG e NaCl.

Published
2018

16. Does discontinuous hydration of Senna spectabilis (DC.) H.S. Irwin & Barneby var. excelsa (Schrad.) H.S. Irwin & Barneby (Fabaceae) seeds confer tolerance to water stress during seed germination?

Author

Lima, Ayslan Trindade, Cunha, Paulo Henrique de Jesus da, Dantas, Bárbara França, and Meiado, Marcos Vinicius

Subjects
seed hydration memory, abiotic stress, estresse abiótico, tempo hídrico, memória de hidratação de sementes, hydrotime, germinability, germinabilidade, Caatinga
Abstract

Seed hydration memory is the ability of seeds to retain biochemical and physiological changes caused by discontinuous hydration. This study aimed to determine if Senna spectabilis (DC.) H.S. Irwin & Barneby var. excelsa (Schrad.) H.S.Irwin & Barneby (Fabaceae) present seed memory and evaluate the effects of hydration and dehydration cycles (HD) on the seed germination of this species when submitted to conditions of water stress. Seeds underwent HD cycles (0, 1, 2 and 3 cycles) corresponding to the hydration times X (6 hours), Y (16 hours) and Z (24 hours), determined from the imbibition curve, with 5 hours of dehydration and submitted to water stress conditions. Germination was evaluated at 0.0, -0.1, -0.3, -0.6 and -0.9 MPa, obtained with polyethylene glycol 6000 solution. Germinability (%), mean germination time (days) and hydrotime (MPa d-1) were calculated. The seeds of S. spectabilis var. excelsa are sensitive to the low osmotic potentials tested in this study, however, when submitted to the HD cycles of 16 hours hydration (time Y), the tolerance to water stress conditions is increased. In addition, the observed benefits on the evaluated germination parameters show that S. spectabilis var. excelsa present seed hydation memory. Resumo: Memória de hidratação de sementes é a habilidade que as sementes apresentam em reter alterações bioquímicas e fisiológicas ocasionadas pela hidratação descontinua. Este estudo objetivou determinar se sementes de Senna spectabilis (DC.) H.S. Irwin & Barneby var. excelsa (Schrad.) H.S.Irwin & Barneby (Fabaceae) apresentam memória de hidratação e avaliar os efeitos dos ciclos de hidratação e desidratação (HD) na germinação das sementes dessa espécie quando submetidas a estresse hídrico. As sementes passaram por ciclos de HD (0, 1, 2 e 3 ciclos) correspondentes aos tempos X (6 horas), Y (16 horas) e Z (24 horas) de hidratação, determinados a partir da curva de embebição, com 5 horas de desidratação e postas para germinar em condições de estresse hídrico. A germinação foi avaliada nos potenciais 0,0; -0,1; -0,3; -0,6 e -0,9 MPa, obtidos com a utilização da solução de polietileno glicol 6000. Foram calculados a germinabilidade (%), tempo médio de germinação (dias) e tempo hídrico (MPa.d-1). Sementes de S. spectabilis var. excelsa são sensíveis aos baixos potenciais hídricos, porém, quando submetidas aos ciclos de HD no tempo Y (16 horas), há um aumento na tolerância às condições de estresse hídrico. Além disso, os benefícios observados nos parâmetros germinativos mostraram que S. spectabilis var. excelsa apresenta memória de hidratação da semente.

Published
2018

17. GerminaQuant: a new tool for germination measurements

Author

Marques, Felipe Rafael Ferreira, Meiado, Marcos Vinicius, Castro, Natália Maria Corte Real de, Campos, Mariana Lins de Oliveira, Mendes, Keila Rêgo, Santos, Orlando de Oliveira dos, and Pompelli, Marcelo Francisco

Subjects
tempo médio de germinação, software, mean germination time, synchrony and uncertainty of germination, seed germination, spreadsheet, germinação de sementes, planilhas eletrônicas, sincronia e incerteza na germinação
Abstract

The seed technologies related with germination and seed research has provided unprecedented opportunities for the biologic research community. Researchers require such information to rapidly determine the speed of seedling emergence. However, an immense amount of data must be analyzed to achieve this goal. In this paper, we introduce a computer software designed for broad use to facilitate the understanding of germination processes and their analysis. GerminaQuant 1.0 was written in the C++ programming language and presents a user-friendly interface. The accuracy of the software was tested using fifty different matrices, whose output values were compared with other spreadsheets available on the web. With data analysis, we showed that the GerminaQuant is capable of generating mathematical calculations with extreme accuracy, besides have a good performance and wide ease of use in any kind of computer. In addition, the new software has been tested by at least eighty users, which compared functionality, designer and accuracy of the output data. In all variables, the GerminaQuant was evaluated as superior compared to other spreadsheets available on the web. The full GerminaQuant package (for Windows(r), Macintosh(r) and Linux(r)) is freely available to the scientific community and can be easily downloaded from the website (http://www.ufpe.br/lev). Resumo:A avaliação da velocidade e intensidade de germinação de lotes de sementes têm providenciado oportunidades sem precedentes para a comunidade científica. Pesquisadores requerem tais informações para rapidamente determinar a velocidade de emergência da plântula. Entretanto, uma quantidade extensa de dados é analisada para se alcançar este propósito. Neste artigo, introduzimos um software desenhado para facilitar o entendimento dos processos de germinação e a análise dos dados. O GerminaQuant 1.0 foi escrito em linguagem de programação C++ e apresenta uma interface amigável. A precisão do software foi testada a partir de cinquenta diferentes matrizes, cujos valores de saída foram comparados com outras planilhas de cálculo disponíveis na web. Com a análise dos dados foi mostrado que o GerminaQuant é capaz de gerar cálculos matemáticos com extrema precisão, além de apresentar uma performance amigável, com ampla facilidade de uso em qualquer computador. Ademais, o novo software foi testado para oitenta usuários, os quais compararam a sua funcionalidade design e precisão. Em todas as variáveis, o GerminaQuant foi avaliado como sendo superior quando comparado às demais planilhas disponíveis na web. O GerminaQuant (disponível para Windows(r), Macintosh(r) e Linux(r)) está disponível gratuitamente para download por toda a comunidade científica, através do endereço http://www.ufpe.br/lev.

Published
2015

18. Effect of hydration and dehydration cycles on Macroptilium atropurpureum seeds germination under water deficit conditions.

Author

Lima, Ayslan Trindade, de Oliveira, Daianne Maria, and Meiado, Marcos Vinicius

Subjects
GERMINATION, DEHYDRATION, WATER shortages, OSMOTIC potential of plants, HYDRATION
Abstract

The imbibition process, which is essential for seed germination, can be interrupted due to lack of water in the environment. Once this occurs, seeds have its germination process interrupted and loses the water absorbed to the environment. The objective of this study was to evaluate the effects of hydration and dehydration cycles (HD cycles) on seed germination of Macroptilium atropurpureum under water deficit conditions. Seeds of M. atropurpureum were submitted to 0 (control), 1, 2 and 3 HD cycles at different hydration times. In addition, the seeds were also submitted to osmotic potentials of 0.0, -0.1, -0.3, -0.6 and -0.9 MPa for water deficit simulation. Although the seeds germinated in all of the osmotic potentials used, the seeds presented a reduction in the percentage of germination, independently of the number of HD cycles and the hydration time between each cycle. In addition, HD cycles also negatively affected the mean germination rate, promoting a reduction of this parameter as seeds were submitted to HD cycles and osmotic potentials. Thus, the results demonstrated that HD cycles did not provide an increase in water stress tolerance in M. atropurpureum seeds during germination. [ABSTRACT FROM AUTHOR]

Published
2018
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19. In situ or ex situ seed conservation: which is the more effective way to maintain seed longevity of an endangered cactus?

Author

Nascimento, Joana Paula Bispo and Meiado, Marcos Vinicius

Subjects
*PLANT conservation, *SEED viability, *CACTUS, *ENDANGERED plants, *SEED storage, *GERMINATION
Abstract

With restricted populations and a small number of individuals, Discocactus bahiensis Britton & Rose ( Cactaceae) is an endangered species in Brazil and its capacity for the formation of seed banks in the soil and the maintenance of seed viability remains unknown. Thus, the aim of the present study was to determine the most efficient way to maintain viability during storage of seeds of D. bahiensis. Seeds were stored in paper bags and either kept in a cold chamber (7 ± 2°C) in the dark ( ex situ conservation) or buried in the soil to a depth of 5 cm in an area of natural occurrence of the species ( in situ conservation). Germinability of the seed banks was evaluated monthly for 20 months. During the first 10 months of storage, germinability of the seeds conserved in situ and ex situ was similar to that of recently collected seeds. After this period, a 70% reduction in germinability was found for the seeds maintained in situ and there was nearly complete loss of viability after 12 months of storage in the field (germinability < 10% in the last 8 months of the experiment), indicating the ability to form persistent soil seed banks. In contrast, the seeds stored in the cold chamber maintained greater than 70% germinability throughout the entire analysis period, demonstrating that ex situ conservation is the most efficient way to maintain the viability of the seeds of this endangered species. [ABSTRACT FROM AUTHOR]

Published
2017
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20. Effects of light and temperature on seed germination of cacti of Brazilian ecosystems.

Author

Meiado, Marcos Vinicius, Rojas‐Aréchiga, Mariana, de Siqueira‐Filho, José Alves, and Leal, Inara Roberta

Subjects
*EFFECT of temperature on plants, *GERMINATION, *CACTUS, *LIGHT sources, *CAATINGA plants, *CERRADOS
Abstract

Environmental factors are used by plants as spatio-temporal indicators of favorable conditions for seed germination. Thus, the objective of this study was to determine the effect of light and temperature on seed germination of 30 taxa of Cactaceae occurring in northeastern Brazil and to evaluate whether fluctuations in temperature are capable of altering light sensitivity. The seeds were tested for germination under two light conditions (12 h photoperiod and continuous darkness) and 10 temperature treatments: eight constant temperatures (10, 15, 20, 25, 30, 35, 40 and 45°C) and two alternating temperatures (30/20°C and 35/25°C). The species studied showed two photoblastic responses. All cacti from the Cactoideae subfamily (22 taxa) were classified as positive photoblastic (i.e., no germination in darkness), regardless of the temperature treatment used. Likewise, temperature fluctuation did not alter the seed sensitivity to light. On the other hand, the species of the Opuntioideae (five taxa) and Pereskioideae (three taxa) subfamilies are indifferent to light (i.e., germinated both in the presence and absence of light). The cacti from the areas of Caatinga and Cerrado showed an optimal germination temperature of 30°C, while the species from Atlantic Forest and Restinga areas showed an optimal germination temperature of 25°C. [ABSTRACT FROM AUTHOR]

Published
2016
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22. How habitat change and rainfall affect dung beetle diversity in Caatinga, a Brazilian semi-arid ecosystem.

Author

Liberal, Carolina Nunes, de Farias, Ângela Maria Isidro, Meiado, Marcos Vinicius, Filgueiras, Bruno K. C., and Iannuzzi, Luciana

Subjects
DUNG beetles, FRAGMENTED landscapes, SPECIES diversity, FOREST animals, BIOTIC communities, LINEAR statistical models
Abstract

The article focuses on a research conducted in order to evaluate the effects of forest disturbance and rainfall on dung beetle communities in their abundance, species richness, and diversity in Caatinga, a semi-arid ecosystem in northeastern Brazil. It discusses the comparison of abundance and species richness of dung beetle between the two environments and two seasons by using a generalized linear model with a Poisson error distribution.

Published
2011
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23. Seed germination responses of Cereus jamacaru DC. ssp. jamacaru (Cactaceae) to environmental factors.

Author

MEIADO, MARCOS VINICIUS, DE ALBUQUERQUE, LARISSA SIMÕES CORRÊA, ROCHA, EMERSON ANTÔNIO, ROJAS‐ARÉCHIGA, MARIANA, and LEAL, INARA ROBERTA

Subjects
*GERMINATION, *CACTUS, *CEREUS, *CAATINGA plants
Abstract

In the present study, we assessed the seed germination responses of Cereus jamacaru DC. ssp. jamacaru (Cactaceae) to environmental factors. The seeds were collected from an area within Caatinga, a semiarid vegetation area located in north-eastern Brazil. We determined the optimal temperature for germination of C. jamacaru seeds and evaluated the effect of temperature, light intensity, light quality, water and saline stress on seed germination. Cereus jamacaru was classified as a positive photoblastic species. Maximum germination (95.8 ± 2.6%) was found under white light, and seed germination was not observed in darkness in any of the temperature, water or saline stress treatments. The optimum temperature for seed germination was 30°C because this temperature favored most of the parameters evaluated. Seed germinability responded positively to a wide range of temperatures, but was affected neither by light intensity nor by light quality. A reduction in water availability and an increase in saline concentration affected germinability and promoted slower, unsynchronized germination. The positive response of C. jamacaru seed germination to the environmental factors investigated may account for the abundant occurrence and wide distribution of the species in the Caatinga area. [ABSTRACT FROM AUTHOR]

Published
2010
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