Lúcia Helena de Moura Sena

Germination and vigor of Dimorphandra mollis benth. seeds under different temperatures and substrates

The Dimorphandra mollis Benth. - Caesalpiniaceae is a native forest species coming from the Cerrado and Caatinga due to its economical and ecological use, which justifies the studies on seed germination. In this work, germinative performance of D. mollis seeds were studied in different conditions of temperature regime and substrate. The experimental delineation used was completely randomized in factorial 4 x 4 (4 substrates -sand, coconut fiber, vermiculite and paper towel; and 4 temperatures: 25, 30, 35 and 20-30oC), with four replications of 25 seeds each. The following parameters were evaluated: seed moisture content, final germination, first germination count, germination speed index, length and dry matter weight. The best germination and vigor is obtained at 30 and 35oC. The substrates paper towel and vermiculite allow satisfactory germinative performance of seeds, being suitable to evaluate the physiological quality of D. mollis seeds.

Physiological quality of surinam cherry seeds submitted to different procedures of drying and substrates - Part 1.

The present work had as its objective to determine the ideal procedure of drying and the substrate to evaluate the viability and vigour of surinam cherry seeds (Eugenia uniflora L.). The experiment was developed in a completely randomized design in factorial scheme 2 x 4 (2 procedures of drying: shade and sun; 4 substrates: sand, vermiculite, coconut fiber and paper towels) with four replications of 25 seeds each. The water absortion curve was characterized and the following parameters were analyzed: germination percentage, first germination count (%), germination speed index and dead seeds (%). The experiment was conducted in a BOD germinator regulated at constant temperature of 25 oC and regime of continuous light. In the conditions where the work was carried out, the drying under shade and vermiculite may be recommended to evaluate the vigour because they provided the best germination and initial development of surinam cherry seedlings.

Efeito do tipo de embalagem e do ambiente de armazenamento sobre a germinação e o vigor das sementes de Apeiba tibourbou AUBL.

This work had as objective of evaluating the effect of different packings and different storage environments in the maintenance of the germination and the vigor of Apeiba tibourbou seeds. The seeds were conditioned in the folowing packings: transparent glass containers, the Kraft paper bags and transparent polyethylene bags stored under following environments: environmental conditions of laboratory, in the freezer and in chamber. In the beginning and at every 45 days of storage was determined the seed moisture content and carried out germination and vigor tests. The results showed that the seeds present the largest germination and vigor when conditioned in Kraft paper bags and polyethylene bags, under environments conditions of laboratory.

Métodos para superação da dormência de sementes de quixabeira ( Sideroxylon obtusifolium (Roem. & Schult.) T.D.Penn.).

Due to absence of information about the methodology for the evaluation of the physiological quality of seeds of medicinal arboreal species seeds, the aim of the present work was to determine the most efficient method to overcome the seed coat dormancy in seeds of Sideroxylon obtusifolium (Roem.& Schult.) T.D.Penn. Besides the intact seeds, the ones which had not been submitted to any treatment, the following pre-germinating methods were used: chemical scarification: the seeds were immersed in pure sulfuric acid for 10, 20, 30, 40, 50 and 60 minutes at the environment temperature (27oC ± 1oC); mechanical scarification: the seeds were rubbed manually in sandpaper number 50, in the opposite side of micropyle, without and with soaking for 24 or 48 hours; thermal scarification: immersion in water at 100oC for 15 or 30 seconds; immersion in water to 80oC until cooling. The effects of treatments were evaluated through tests of germination and vigor. There were significant differences among the treatments for all the evaluated parameters (percentage and speed of germination, length and dry weight of shoot and root), and the most evident cause of dormancy was the coat impermeability, which efficiency was overcame by the immersion of seeds in pure sulfuric acid for 30 minutes.

Allelopathic effect of aqueous extract of Mimosa caesalpiniaefolia Benth. in seed germination of Phaseolus lunatus

The Mimosa caesalpiniaefolia Benth. is a medicinal plant that can be used in agroforestry systems, is also employed in the composition of pasture trees in strips between fields, to enrich brush fields and as a hedge. The Phaseolus lunatus L. is one of four species of the genus Phaseolus exploited commercially; its use is preferably in the form of green beans cooked or in canned form. The aim of the present research was to evaluate aqueous extracts of Mimosa caesalpiniaefolia on the germination of seeds and initial growth of broad beans seedlings. The seeds of bean were sowed into vermiculite in boxes and placed in a germinador at 25 °C under continuous light. The substrate was moistened with the aqueous extract of young leaves of Mimosa caesalpiniaefolia in concentrations of 25%; 50%; 75%, 100%, and a control treatament whose substrate was moistened only with distilled water. The parameters evaluated were: percentage, first count, the index of germination speed and length of the primary root. The experimental design was completely randomized design with four replications of 25 seeds each. The data were subjected to analysis of variance and regression polynomial. In the study of polynomial regression (p < 0,05) equation was used to best fit the data. The values in percentage were transformed in arc sen (n/100) 0,5 . It was concluded that different

Germinação e vigor de plântulas de Parkia platycephala Benth. em diferentes substratos e temperaturas

Conhecida popularmente como fava de bolota, a Parkia platycephala Benth. pertence a familia Fabaceae, ocorre em areas de transicao Caatinga-Cerrado e apresenta grande potencial madeireiro, paisagistico e, principalmente, forrageiro. O objetivo da pesquisa e fornecer informacoes para a elaboracao de protocolos de testes de germinacao de sementes e vigor de plântulas de P. platycephala, submetidas a diferentes subtratos e temperaturas. Para avaliar o efeito do substrato e da temperatura, as sementes foram semeadas entre os substratos: vermiculita, areia, po de coco, bagaco da cana-de-acucar, tropstrato®, papel (RP), marca Germitest e papel mata-borrao, distribuidas em caixas plasticas transparentes, todos sob luz continua em germinador tipo Biochemical oxygen Demand (B.O.D.), com temperaturas constantes de 5; 10; 15; 20; 25; 30; 35 e 40 °C, e temperaturas alternadas de 20-30 oC e 25-35 oC. Foram avaliadas as variaveis germinacao, indice de velocidade de germinacao, tempo medio da germinacao, comprimento da raiz primaria e da parte aerea, e massa seca da raiz primaria e da parte aerea. A temperatura alternada de 25-35 °C combinada com o substrato vermiculita e recomendada para realizacao de testes de germinacao e vigor de P. platycephala.

Vigor das sementes de Apeiba tibourbou Aubl. sob difrentes condições de armazenamento e embalagens.

This study had the objective of evaluating the vigor of Apeiba tibourbou seeds submitted to different storage and packaging conditions, during 225 days. After processing, the Apeiba tibourbou seeds were conditioned in the following packages: transparent glass containers, Kraft paper bags and transparent polyethylene bags and stored under the following conditions: room temperature in a laboratory (24.8oC to 28oC; UR 68.9 to 82.5%), in a freezer (-20oC; UR 90%) and in a chamber (18.5 ± 1oC; UR 71 ± 3%). At the beginning and every 45 days, during 225 days of storage, the seed moisture content was determined and a vigor test was carried out (percentage and index of speed of emergence, length (cm) and dry weight matter (mg) of seedling). Among the storage conditions studied, the most suitable for conservation of Apeiba tibourbou seeds for 180 days, with less loss of vigor was the natural environment of the laboratory, when using the polyethylene bag packaging.

Superação da dormência em sementes de crista de galo

This study had the objective of evaluating the effect of different pre-germination treatments for overcome of dormancy of Celosia cristata seeds, subjected to the following treatments: heat shock - exhibition in an oven at 80°C for 5 minutes, chemical scarification with sulfuric acid for 1 minute, 30 seconds and 5 minutes, immersion of intact seeds in water the 80°C at cooling and immersion of intact seeds in water for 24 hours, and the control - no treatment. We evaluated the following final percentage, first count and germination speed index, but also the length of the primary root and hypocotyl. The seeds of C. cristata when coming from ripe fruits do not require the use of treatments to overcoming dormancy.

MORFOLOGIA DO FRUTO, SEMENTE E PLÂNTULA DE ESCHWEILERA OVATA (CAMBESS.) MIERS

O estudo morfologico de sementes e plântulas, com o objetivo de obter um maior conhecimento de suas estruturas, alem de fornecer informacoes sobre a germinacao, viabilidade, armazenamento e metodos de semeadura, auxilia a analise do ciclo vegetativo das especies, fornecendo informacoes relativas a identificacao. O principal objetivo deste trabalho foi desenvolver metodologia de identificacao morfologica de frutos, sementes e plântulas de imbiriba ( Eschweilera ovata (Cambess.) Miers), por meio de descricoes e ilustracoes das caracteristicas morfologicas externas e internas. Os frutos e as sementes foram colhidos no Parque Estadual de Dois Irmaos, no municipio de Recife-PE e conduzidos em sacos de polietileno para o Laboratorio de Sementes do Departamento de Agronomia da Universidade Federal Rural de Pernambuco. Foi realizada caracterizacao morfologica dos frutos, sementes e plântulas, sendo tomadas as medidas de comprimento e largura. A descricao foi feita com auxilio do microscopio estereoscopico binocular. As sementes foram desinfestadas com solucao de hipoclorito de sodio a 5% durante cinco minutos e semeadas em substrato sobre vermiculita, esterilizado e umedecido com solucao de nistatina a 0,2%. Constatou-se que os frutos constituem-se em um pixidio, fruto seco, em forma de sino. As sementes de imbiriba apresentam arilo funicular lateral e endosperma abundante, possuem germinacao hipogea, sendo a plântula classificada como criptocotiledonar, ocorrendo poliembrionia em torno de 4%.

MÉTODOS PARA SUPERAÇÃO DA DORMÊNCIA EM SEMENTES DE Garcinia gardneriana (Planch. & Triana) Zappi

Garcinia gardneriana is a native tree species of the Atlantic Forest biome with commercial potential, industrial application, medicinal, ornamental and timber, which seeds have difficulties on germination. In this sense, the objective of the present study was to evaluate different methods to overcome dormancy efficiently and at low cost to promote rapid and uniform seed germinations of this species. In order to study the influence of different methods to G. gadneriana overcome dormancy, the following treatments were tested: control, intact seeds without any treatment (T 1 ); seeds without seed coat (T 2 ); seeds without seed coat, followed by immersion in a solution of gibberellic acid (GA 3 ) 500 mg.L -1 for 24 hours (T 3 ); seeds without seed coat, followed by immersion in a solution of potassium nitrate (KNO 3 ) at 0,2% for 24 hours (T 4 ); seeds without seed coat, followed by laminating at 10°C for 120 hours (T 5 ); seeds with seed coat and soaked in solution of potassium nitrate (KNO 3 ) at 0,2% for 24 hours (T 6 ); stratifying the seeds subjected to 10°C for 120 hours (T 7 ); seeds scarified with sandpaper to mass no 80 opposite the hilum (T 8 ). For dormancy overcome were evaluated: total emergency, first emergency count, emergency speed index, mean emergency time, length and dry weight of seedlings root and seedlings root. The removal of the seed coat favors the emergence of more vigorous seedlings derived from Garcinia gardneriana seeds, so exhibit dormancy coats (exogenous). The seed soaking in gibberellic acid solution can accelerate the emergence speed index but does not influence the mean emergency time. It is recommended as treatments to dormancy overcome of Garcinia gardneriana , the seeds without seed coat, followed by immersion in a solution of gibberellic acid (GA 3 ) 500 mg.L -1 for 24 hours or only seeds without seed coat to be a more practical treatment.