Elane Grazielle Borba de Sousa Ferreira

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.

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

Tratamentos pré-germinativos em sementes de duas espécies do gênero Poincianella

Objetivou-se nesse trabalho avaliar o efeito de diferentes tratamentos pre- germinativos em sementes de Poincianella bracteosa e Poincianella pyramidalis. Foram testados os seguintes tratamentos: embebicao em agua por 24 horas; embebicao em agua a 80 oC ate atingir a temperatura ambiente; escarificacao com lixa; escarificacao com lixa seguida da embebicao em agua por 24 horas; escarificacao quimica com acido sulfurico concentrado por 30 segundos, 1; 5 e 10 minutos e a testemunha. A avaliacao do efeito dos tratamentos foi feita pelas variaveis: germinacao, primeira contagem e indice de velocidade de germinacao, comprimento da raiz principal e da parte aerea e a determinacao da massa seca da raiz e da parte aerea das plântulas. Concluiu-se que as sementes de P. bracteosa e P. pyramidalis nao apresentam dormencia tegumentar.

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.

PROCESSO GERMINATIVO E VIGOR DE SEMENTES DE Cedrela odorata L. SOB ESTRESSE SALINO

The objective of this study was to evaluate the effects of salt stress on the viability and the vigor of Cedrela odorata L. seeds. The experiment was conducted at conditions of laboratory (temperature medium from 28 oC and humidity medium of 84 %), under continuous light where four replicates of 25 seeds were put to germinate on blotting paper and moistened with solutions of NaCl, KCl and CaCl 2 at different concentrations (0, 25, 50, 75 and 100 mM). The parameters analysed were: germination, first germination count, germination speed index, primary root and hypocotyl length and dry weight matter of the seedling. The adverse effects of salt stress on germination and seedling vigor of ‘cedro’ are indeed evident from the concentration of 25 mM NaCl, KCl and CaCl 2 , indicating that their use in saline environments may be limited. The ‘cedro’ seeds are more sensitive to CaCl 2 and KCl compared to NaCl, the effect of salinity was more aggressive on the germination and vigor than in seedling vigor.