Edna Ursulino Alves

Superação da dormência em sementes de Bauhinia divaricata L.

This study was carried out with the aim of determining the most efficient methodology to overcome dormancy in Bauhinia divaricata seeds. The 12 treatments employed were: control - intact seeds (T1); mechanical scarification with sandpaper (T2); coating cutting in the opposite side of micropylar region (T3); immersion in water and at room temperature during 24 hours (T4); immersion in water (50, 60 and 70oC) during three minutes (T5, T6 and T7, respectively); immersion in hot water (80oC) during three, six and nine minutes (T8, T9, and T10, respectively); and immersion in boiling water during one and two minutes (T11 and T12, respectively). Effects were evaluated considering emergency and vigor tests (first count, speed mean time to emergency, length and dry mass of seedlings and relative frequency emergency). The experiment was installed in greenhouse and sown was done in plastic trays containing sand. The experimental design used was a completely randomized with four replicates of 25 seeds and the averages were compared through the Tukey test, at 5% probability. The were significant differences among the treatments for all variables. The most probable cause for the dormancy is the impermeability of the seed coating and the most efficient treatment to overcome were coating cutting in the opposite side of micropylar region.

Ácido sulfúrico superação da dormência de unidade de dispersão de juazeiro (Zizyphus joazeiro Mart.)

O Zizyphus joazeiro Mart. apresenta reducao sensivel no numero de individuos em seu ambiente natural devido, entre outras causas, a ocorrencia de dormencia exogena da unidade de dispersao (impermeabilidade a agua). Avaliou-se o efeito do periodo de imersao (0, 30, 60, 90, 120 e 150 min) dessas unidades de dispersao, em acido sulfurico (98 %), na emergencia e vigor das sementes (primeira contagem, indice de velocidade e tempo medio de emergencia, altura e massa seca de plantas). O experimento foi realizado em casa de vegetacao, utilizando-se o delineamento inteiramente ao acaso, com seis tratamentos e quatro repeticoes. O pre-condicionamento das unidades de dispersao de Zizyphus joazeiro Mart., em acido sulfurico concentrado, mostrou-se eficiente na superacao da dormencia dessa especie, promovendo aumento na porcentagem e velocidade de emergencia, primeira contagem de emergencia, na altura e massa seca de plantas e reducao no tempo medio para emergencia. A eficiencia do tratamento quimico com acido sulfurico concentrado depende do periodo de imersao, sendo a faixa entre 74 e 115 min mais adequada para proporcionar maiores porcentagens de emergencia e de vigor.

Superação da dormência em sementes de Caesalpinia pyramidalis Tul

n Forest species with hard seeds often cause important problems for nursery managers because their hard and water impermeable seed coats hinder and delay germination. For this reason, an experiment was carried out to determine methodologies for overcoming dormancy of catingueira seeds, under greenhouse conditions, in the Center for Agricultural Sciences, of the Federal University of ParaIba. The experiment was arranged in a complete randomized design, with four replicates of 25 seeds/treatment. Seeds were subjected to 12 treatments: control - intact seeds (T 1 ), mechanical scarification using fine sandpaper n o . 80 (T 2 ), coating cutting in the opposite side of micropylar region (T 3 ), immersion in sulfuric acid (98%) for 6, 8 and 10 minutes (T 4 , T 5 and T 6 , respectively), immersion in water at 60, 70 and 80 o C for one minute (T 7 , T 8 and T 9 , respectively), immersion in water at room temperature for 24, 48 and 72 hours (T 10 , T 11 and T 12 , respectively). The seeds

Substratos e temperaturas para testes de germinação e vigor de sementes de Amburana cearensis (Allemão) A.C. Smith

Amburana cearensis (Allemao) B.C. Smith is a species native to the Northeast Region of Brazil. It has been increasingly exploited for fine woodworking, perfumery and medicine, therefore the need for studies that can assist in its preservation. The objective of this work was to determine substrate type and optimum temperature for A. cearensis seed germination and vigor tests. The experiment was car ried out in complete randomized design with the treatments distributed in a 5 x 5 factorial scheme, using temperatures (constant of 20, 25, 30 and 35oC and alternate of 20-30oC) and substrates (Germitest paper , sand, vermiculite, bioplant and plantmax) with four replicates of 25 seeds each. The following parameters were analyzed: germination percentage, germination speed, length and dr y mass of seedlings. The optimum temperatur e for A. cearensis seed germination and vigor tests was 35oC, independently of the used substrates. The substrates sand and vermiculite were the most suitable for evaluation of the physiological quality of seeds.

Emergência de plântulas de Erythrina velutina em diferentes posições e profundidades de semeadura

The aim of this research was to study the influence of the sowing depth and position upon seedling emergency and seed vigor of the coral tree, some germination tests were settled in sand, under protected environment. The treatments were represented by the position and depth of the seed sowings relative to the substratum, as follows: seed with the hilum turned down, upward and to the side at depths 1, 2, 3, 4 and 5cm. Each treatment consisted of four replicates with 25 seeds, and were evaluated by the following tests: emergence, first-counting vigor, emergency speed, length and dry mass of the hypocotyl and roots. According to the results for coral tree, the sowing depth should be between one and two centimeters, whereas the best position was the hilum turned down.

Superação da dormência em sementes de faveira (Parkia platycephala Benth)

RESUMO ‐ A faveira e planta semidecidua, heliofita, que ocorre em formacoes secundarias e areas abertas de terreno elevado do agreste nordestino e campinas amazonicas. A madeira dessa especie e empregada para caixotaria, compensados, brinquedos, lenha e carvao, as vagens maduras constituem-se em excelente forragem para todos os ruminantes e a arvore e recomendada para arborizacao paisagistica. O primeiro problema encontrado foi a baixa germinacao das sementes devido a impermeabilidade do tegumento a agua. Dessa forma, este trabalho teve o objetivo de determinar a metodologia mais eficiente para superacao da dormencia de sementes de Parkia platycephala, as quais foram submetidas a 12 tratamentos: testemunha - sementes intactas (T 1 ), escarificacao mecânica com lixa d’agua n. 80 (T 2 ), imersao em acido muriatico concentrado (98%) por 30 min e 1 h (T 3 e T 4 , respectivamente), escarificacao mecânica com brita por 5, 10 e 15 min (T , T 6 e T 7 , respectivamente) e imersao em acido sulfurico concentrado (98%) por 5, 15, 30, 45 e 60 min (T 8 , T 9 , T 10 , T 11 e T 12 , respectivamente). Os efeitos dos tratamentos foram avaliados atraves da porcentagem, primeira contagem e indice de velocidade de emergencia de plântulas, alem de comprimento e massa seca da raiz e parte aerea. Utilizou-se o delineamento inteiramente casualizado com quatro repeticoes, e as medias foram comparadas pelo teste de Tukey a 5% de probabilidade. Houve diferenca significativa entre os tratamentos em todas as variaveis. A causa mais evidente da dormencia foi a impermeabilidade do tegumento, cujos tratamentos mais eficientes para superar a dormencia das sementes foram a escarificacao mecânica do tegumento com lixa e a imersao em acido sulfurico (15 a 45 min).

Utilization of cattle manure and earthworm compost on hybrid cabbage production

The use of bovine manure and earthworm compost were compared in cabbage production, hybrid Matsukaze, at the Federal University of Paraiba, Brazil, from December 1997 to March, 1998. The treatments consisted of 20; 30; 40; 50 and 60 t/ha of bovine manure and 10; 15; 20; 25 and 30 t/ha of earthworm compost and a treatment without organic matter (control). The experimental design was of randomized blocks, with eleven treatments arranged in a factorial scheme (5 x 2) + 1, with four replications. The longitudinal and transversal diameters, format index and head compactness, average weight and total production of heads were evaluated. The level of 46.0 t/ha of bovine manure and 29.0 t/ha of earthworm compost resulted in larger longitudinal diameters of cabbage heads (13 and 12 cm, respectively). The level of 47.0 t/ha of bovine manure and 20.0 t/ha of earthworm compost provided heads with larger transversal diameters (13 and 11 cm). All bovine manure levels induced the formation of more uniform and compact heads, while the use of 20 t/ha of earthworm compost resulted in not uniform heads with low commercial value. The level of 41.0 t/ha of bovine manure promoted maximum average head weight (900 g) and yield (47.0 t/ha), while the use of 27.0 t/ha of earthworm compost was responsible for the maximum average head weight (700 g) and yield (38.0 t/ha), respectively.

Características e rendimento de vagem do feijão-vagem em função de fontes e doses de matéria orgânica

Com o objetivo de avaliar doses e fontes de materia orgânica na cultura do feijao-vagem, cultivar Macarrao Trepador, instalou-se um experimento em condicoes de campo no periodo de julho a novembro de 1998, no Centro de Ciencias Agrarias da Universidade Federal da Paraiba. O delineamento experimental empregado foi blocos casualizados, em esquema fatorial 4 x 5, compreendendo quatro fontes de materia orgânica (esterco de galinha, esterco bovino, esterco caprino e humus de minhoca) e cinco doses, sendo 0; 5; 10; 15 e 20 t/ha de esterco de galinha; e, 0; 10; 20; 30 e 40 t/ha de esterco bovino, caprino e humus de minhoca, em quatro repeticoes. Utilizaram-se parcelas com 20 plantas, espacadas de 1,00 x 0,50 m. Os resultados indicaram que o comprimento de vagens aumentou linearmente com as doses de estercos de galinha, de bovino e de caprino. O peso medio de vagens foi influenciado apenas pelo esterco de galinha. O humus de minhoca nao exerceu efeito sobre a caracteristica e a produtividade de vagens. O esterco de galinha na dose de 13,0 t/ha proporcionou rendimento maximo de vagens (26,3 t/ha), o esterco bovino na dose de 24,0 t/ha produziu 30,3 t/ha e o esterco caprino, na dose de 16,6 t/ha, produziu 23,0 t/ha. A analise economica indicou a dose de 11 t/ha de esterco de galinha e de 23,0 t/ha de esterco bovino, como as mais viaveis economicamente para adubacao orgânica no feijao-vagem, resultando num rendimento estimado de 11,3 e 21,2 t/ha de vagens e uma receita prevista de 8.000 e 21.000 kg/ha de vagens, respectivamente. Para o esterco caprino, 20 t/ha apresentou saldo um pouco superior a sua ausencia, enquanto 10 t/ha de humus de minhoca revelou saldo de R

Armazenamento de sementes de Myracrodruon urundeuva Fr. All. em diferentes embalagens e ambientes

2.336,00/ha, porem, inferior a sua ausencia. Conclui-se, pois, que nas condicoes em que foi realizada a presente pesquisa, nao e vantajoso o emprego do esterco caprino e do humus de minhoca como fontes de materia orgânica para programas de producao de vagens em feijao-vagem.

Germinação e vigor de sementes de Crataeva tapia L. em diferentes temperaturas e regimes de luz

Storage of Myracrodruon urundeuva Fr. All. seeds in different packaging and environments. Myracrodruon urundeuva Fr. All. is a species belonging to the Anacardiaceae family, which can be utilized as a medicinal plant, or in the leather tanning industry, urban afforestation, and the production of wood with great mechanic resistance. The objective of this study was to determine the best conditions and storage periods for preserving the viability and vigor of M. urundeuva. Seeds conditioned in bags of Kraft paper, cotton, polyethylene or aluminum foil of mesh polyethylene were stored at room temperature (25 ± 2oC), freezer (-20 ± 2oC), cold (8 ± 2oC) and refrigerator (6 ± 2oC). At 30, 60, 90, 120, 150, 180, 210 and 240 days they were evaluated for seed moisture content, percentage of emergence, emergence speed index (ESI), seedling length and seedling dry matter. In the natural environment of the laboratory, there was no conservation of seed vigor M. urundeuva. The best M. urundeuva seed conservation condition was obtained with bags of Kraft paper, cotton, polyethylene or aluminum foil of mesh polyethylene in the refrigerator or freezer. M. urundeuva seeds can also be kept in paper bags or aluminum foil when stored in a refrigerated chamber, for 240 days. Seed vigor change in this species is initially identified by decrease in the speed emergence.