Salvador Barros Torres

Physiological maturity in gherkin (Cucumis anguria L.) seeds

The objective of this study was to evaluate the physical and physiological changes in the maturation of gherkin (Cucumis anguria L.) seeds since these aspects are important for high quality seed production and reducing seed deterioration in the field. Seeds were collected from fruits of the Norte cultivar at five-day intervals from the 15th to the 40th day after anthesis. The statistical design was completely randomized with six treatments (fruit ages) and four replications. For each fruit age, the fruits were evaluated visually and the mean weight determined. The seeds were evaluated regarding: moisture content, seed dry mass, germination, first count of ermination, electrical conductivity, accelerated aging, and emergence speed index. The maximum physiological quality was found in seeds collected 32 days after anthesis but the best time to harvest the fruits was from 35 to 40 days after anthesis when the seeds showed the lowest moisture content.

Electrical conductivity test in sesame seeds.

The electrical conductivity test, initially developed for pea seeds, has been intensively used to evaluate seed vigor of several plant species. The objective of the present study was to establish methodology for the electrical conductivity test in sesame (Sesamum indicum L.) seeds, involving periods of seed imbibition, water volume and temperatures. In two stages of the study, four seed lots, cv. Preta, were evaluated by the germination test, first germination count, emergence speed, seedling shoot dry matter, seedling shoot length and field emergence, as well seed moisture content determination. For the electrical conductivity test, variations in water volume (25, 50 and 75 mL) or temperature (20, 25 and 30 o C) and in imbibition period (1, 2, 4, 8, 12, 16 and 24 hours) were studied. The electrical conductivity test was efficient for the evaluation of sesame seed physiological potential and the association of 50 seeds, 50 mL distilled water and 8 hours imbibition at 25 o C was the most adequate.

Teste de deterioração controlada em sementes de maxixe

Research has emphasized the relationship of standard germination test and vigor on seedling emergence and stand establishment. In contrast, information relating seed vigor to plant performance is less available. The controlled deterioration as a means to evaluate the vigor of gherkin seeds was studied. Five lots of cultivar Liso were submitted to tests of germination, greenhouse seedling emergence, accelerated aging with saturated solution of NaCl, electrical conductivity and controlled deterioration (19; 21 and 24% water content, at 45oC, for 24 and 48 hour periods). The 24% water content/24 h/45oC combination, for the controlled deterioration test, was efficient to detect vigor differences between gherkin seed lots.

Envelhecimento acelerado em sementes de berinjela

The objective of the present work was to study the methodology of the accelerated aging test to evaluate the physiological quality of eggplant (Solanum melongena L.) seeds, when compared to the saturated salt accelerated aging. Fours lots of the Embu cultivar were tested for germination, seedling emergence, traditional and saturated salt accelerated aging at 41oC for 48, 72 and 96h. It was concluded that further research is still needed to adjust the accelerated aging test procedures to assess seed vigor of eggplant seeds.

Envelhecimento acelerado em sementes de pepino com e sem solução salina saturada

Different procedures of the accelerated aging test were evaluated to obtain the physiological quality of cucumber (Cucumis sativus L.) seeds and the efficiency of using saturated salt solution in the control of water uptake by seeds. Five seed lots of the cv Rubi, were tested for germination, seedling emergence, conventional accelerated aging and salt saturated accelerated aging tests. Results showed that the accelerated aging test (conventional and salt saturated), using the 72 and 96 h, at 38 or 41oC combinations was sufficiently sensitive to detect differences in physiological quality of cucumber seeds. We observed that seed water content after the salt saturated accelerated aging was lower and more uniform, thus presenting advantages in relation to the conventional procedure.

Tetrazolium test for the viability of gherkin seeds

The tetrazolium test is a quick and effective method for evaluating viability in seeds. The aim of this study was to determine a methodology for using the tetrazolium test, and its efficiency in verifying viability in seeds of the gherkin (Cucumis anguria L.). Consequently, five batches of gherkin seed were initially evaluated by the tests for germination, first count and speed of germination. The batches were then subjected to treatments in order to adjust the methodology for the tetrazolium test, evaluating three concentrations of tetrazolium solution (0.100, 0.075 and 0.050%), kept in the dark for two, four and six hours, under temperatures of 35 °C and 40 °C, with four replications of 25 seeds per treatment. At the end of the staining period, the seeds were washed in running water, split lengthways between the cotyledons, and classified as viable and non-viable. Evaluation of viability in seeds of the gherkin by tetrazolium test is efficient when carried out at a concentration of 0.050%, either for six hours at 35 °C or four hours at 40 °C.

Hydropriming and storage of melon seeds.

A tecnica de hidratacao controlada das sementes vem sendo utilizada como metodo de condicionamento fisiologico objetivando melhorar o desempenho destas no campo. O trabalho teve por objetivo avaliar o efeito do hidrocondicionamento fisiologico de sementes de melao durante o armazenamento. Foram realizados testes de germinacao, primeira contagem de germinacao, emergencia de plântulas em casa de vegetacao e envelhecimento acelerado. Utilizaram-se quatro lotes de sementes de melao de dois hibridos, Imperial e Gaucho. O condicionamento fisiologico foi avaliado durante os periodos de armazenamentos de 0, 30, 60 e 90 dias, sob condicoes controladas de 15oC e 45% UR. As sementes condicionadas de melao e armazenadas por 90 dias apresentam resultados superiores de germinacao, primeira contagem de germinacao, emergencia de plântulas e envelhecimento acelerado quando comparadas com as sementes que nao foram submetidas a esse tratamento. O armazenamento de sementes de melao em condicoes controladas (15oC e 45% UR) permite a manutencao dos efeitos beneficos do hidrocondicionamento pelo periodo de 90 dias.

Teste de condutividade elétrica na avaliação da qualidade fisiológica de sementes de coentro

Os testes de germinacao e de vigor sao componentes essenciais do processo de controle de qualidade das empresas produtoras de sementes. Diante disso, nesta pesquisa o objetivo foi estudar a metodologia do teste de condutividade eletrica, verificando sua eficiencia na identificacao de diferentes niveis de vigor de lotes de sementes de coentro. Para tanto, utilizaram-se quatro cultivares (Portugues, Super Verdao, Tabocas e Verdao), cada uma representada por quatro lotes de sementes, que inicialmente foram submetidas as avaliacoes do grau de umidade, germinacao, primeira contagem de germinacao e emergencia de plântulas. O teste de condutividade eletrica foi realizado com 25 e 50 sementes embebidas em 50 e 75 mL de agua destilada, a 25 oC, por 2, 8 e 24 horas. O teste de condutividade eletrica e eficiente para a avaliacao do potencial fisiologico de sementes de coentro quando conduzido com 50 sementes imersas em 50 mL de agua destilada, a 25 oC, apos duas horas de embebicao.

Physiological maturity of Luffa cylindrica (L.) Roem. Seeds

Maturation of seeds involves a systematic sequence of physical and physiological alterations observed from fecundation until they become independent of the mother plant. These alterations comprehend a set of steps which prepare them for a successful germination in the future, characterized by the synthesis and accumulation of reserves. Thus, the objective was to evaluate the development and physiological quality of seeds of L. cylindrica accessions during maturation. Fruits of L. cylindrica accessions were harvested from the 10th day after anthesis (DAA) until the 50th DAA, at 10-day intervals. In each harvest, fruit fresh weight was determined, and then the seeds were manually extracted and subjected to the following evaluations: 100-seed weight, seed water content, seed dry matter content, seedling emergence and emergence speed index. The experiment was carried out in a completely randomized design, with four replicates, in a 3 x 4 factorial scheme (three L. cylindrica accessions and four harvest periods). At 10 DAA, no seeds were formed in the fruits harvested from any the accessions. The best physiological performance of seeds of the L. cylindrica accessions, under the studied conditions, was found at 50 DAA.

Influência de Myrothecium roridum sobre a germinação de sementes e crescimento de plântulas de meloeiro

Agência de Defesa Agropecuária do Estado do Ceará-ADAGRI, Av. Bezerra de Menezes, 1820 CEP: 60.325-002. São Gerardo Fortaleza, CE, Brasil. Departamento de Ciências Vegetais, Universidade Federal Rural do Semi-Árido – UFERSA, Campus de Mossoró, R. Francisco Mota, 572, CEP 59625-900 Pres. Costa e Silva, Mossoró RN, Brasil. Bolsista Capes. Autor para correspondência: Glauber Henrique de Sousa Nunes (glauber@ufersa.edu.br). Data de chegada: 13/09/2016. Aceito para publicação em: 12/06/2017. 10.1590/0100-5405/179175 RESUMO