Anarlete Ursulino Alves

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.

Influência do tamanho e da procedência de sementes Mimosa caesalpiniifolia Benth. Sobre a germinação e vigor

Mimosa caesalpiniifolia Benth. is a native species from the Northeast region, Brazil, which has been increasingly cultivated from the States of Maranhao to Rio de Janeiro. It presents great potential for urban forestry, hedging and wood production. The present research had as objective to evaluate the influence of the provenance and seed size on the germination and vigor of Mimosa caesalpiniifolia Benth. An experiment was conducted at the Laboratory of Seed Analysis of CCA-UFPB, Areia, Paraiba State, Brazil in a completely randomized design with the treatments arranged in a 3x3 factorial, with three provenances and three size classes , four replicates of 25 seeds. The following characteristics were analyzed: 100-seed weight, seed dimensions, percentage and first counting, germination speed, length and weight of dry matter of primary root and hypocotyl and weight of cotyledon dry matter . It was verified that the germination was not influenced by seed size, however, it was influenced strongly by the provenance. The tests of first count and germination speed were not shown appropriate for seed vigor evaluation, being this better appraised by cotyledon and hypocotyl dry matter. Seed vigor was directly related with size, being thus justified the use of size classes for seedling production.

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

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.

Rendimento de feijão-vagem em função de doses de K2O

Aiming to evaluate the effect of K2O levels on the increase of snap bean yield, an experiment was performed in Paraiba State, Brazil, in a Quartz Psamment soil. The experimental design was of randomized blocks, with six treatments (0; 50; 100; 150; 200 and 250 kg ha-1 of K2O), in four replications. Each plot contained 40 plants spaced 1.0 m x 0.2 m. Pods maximum number/plant (20 pods) and the maximum yield/plant (171 g), were obtained, respectively with 145 and 173 kg ha-1 of K2O, and pods yield reached maximum value around 25,3 t ha-1 at the level of 171 kg ha-1 of K2O. The most economic level of K2O for the production of pods was of 165 kg ha-1. The most economic level represented 96% comparing to that responsible for maximum pods production. The K2O levels that obtained maximum pods production and economic return were correlated, respectively, with 181 and 176 mg dm-3 of K available for the extractor Mehlich 1.

Lima beans production and economic revenue as function of organic and mineral fertilization

Lima beans (Phaseolus lunatus L.) are alternative food and income sources for the population of Northeastern Brazil. In this region, lima beans are consumed either as green or dry grains. However, low yields have been observed, a challenge that could be overcome by adequate organic and mineral fertilization. This work intended to assess lima beans yield, cultivar Raio de Sol, as affected by doses of cattle manure in the presence and absence of mineral NPK fertilization. The experiment was carried out at the Federal University of Paraiba, Brazil, from September, 2004 to May, 2005. The experimental design was of randomized blocks, with four replications, 40-plant plots, spaces of 1.00 x 0.50 between and within rows, respectively. Treatments were displayed in a 6 x 2 factorial, corresponding to manure doses (0, 10, 20, 30, 40 and 50 t ha-1) and presence and absence of NPK. Green and dry grain, and pod yields were analysed, as well as the economic revenue for pods and dry grains. To measure the economic efficiency, pods and dry grains were employed as the exchange units. Maximum pod yields (12.6 and 11.2 t ha-1) were achieved with 21.4 and 23 t ha-1 of manure, with and without NPK, respectively. Highest green grain yields (11.1 and 9.9 t ha-1) were obtained with 21.3 and 22.9 t ha-1 of manure, with and without NPK, respectively. The highest yield of dry grains (3.5 t ha-1) was obtained with 26.6 t ha-1 of manure combined with NPK. In the absence of NPK, the use of cattle manure resulted in an average dry grain yield of 2.0 t ha-1. The maximum economic efficiency for pod production was reached with 17 and 18.6 t ha-1 of manure, with predicted net incomes of 2.88 and 3.36 t ha-1 of pods, in the presence and absence of NPK, respectively. For dry grains, the maximum economic efficiency was achieved with 23 t ha-1 of manure, in the presence of NPK, which produced a net revenue of 2.12 t ha-1 of dry grains.

Desempenho de genótipos de coentro em Areia

Seven coriander genotypes were evaluated (lines HTV 9299, HTV 7299, HTV 0699, HTV 0999,HTV 0199 and cvs. Verdao and Palmeira), in Areia County, Paraiba State, Brazil, from May to July of 2003 in randomized blocks in four replications. Verdao (5,0 kg m-2) and Palmeira (4,3 kg m-2) cultivars and the lines HTV 9299 (4,4 kg m-2), HTV 7299 (4,5 kg m-2) and HTV 0999 (4,3 kg m-2), exhibited the greatest yield of green mass (GM), while the line HTV 0199, with 2.9 kg m-2 of GM, showed the lowest yield. Lines HTV 7299 (0.73) and HTV 0199 (0.81) presented the largest values for the ratio leaves:stalks. Verdao and Palmeira cultivars and lines HTV 7299, HTV 0999, HTV 0699 and 9299 persented 65; 58; 35; 29; 40 and 59%, respectively, of plant bolting (PB) at 42 days after sowing date, while Line HTV 0199 presented only 11%. Line HTV 7299 might be an alternative for coriander cropping in Areia.

Comportamento fisiológico de sementes de pitombeira [Talisia esculenta (A. ST. Hil) Radlk] submetidas à desidratação

Em condicoes normais, as sementes de pitombeira [Talisia esculenta (A. St. Hil) Radlk] perdem a qualidade fisiologica rapidamente, o que dificulta sua utilizacao pelos viveiristas. Em funcao da escassez de pesquisas referentes a dessecacao de suas sementes, o trabalho teve como objetivo avaliar a qualidade fisiologica de sementes de pitombeira submetidas a cinco periodos de secagem (0; 24; 48; 96 e 120 horas). O delineamento experimental foi inteiramente ao acaso, e os dados, submetidos a analise de variância e de regressao polinomial. A avaliacao do efeito dos tratamentos foi realizada atraves da determinacao do teor de agua, porcentagem de germinacao e testes de vigor (primeira contagem, indice de velocidade e tempo medio para germinacao, comprimento e massa da materia seca da raiz primaria e parte aerea). Verificou-se um teor de agua inicial de 40%, o qual foi reduzindo com os periodos de secagem; consequentemente, registraram-se as maiores porcentagens de germinacao (99%) com 53 horas de secagem. Quanto ao vigor, os maiores valores de primeira contagem (78%) e comprimento da parte aerea (11,29 cm) foram obtidos com 38 horas de secagem; ja o menor tempo medio para germinacao (17 dias) e comprimento maximo da raiz primaria (15,79 cm) ocorreram quando a secagem foi por 40 horas. Quanto ao indice de velocidades de germinacao (1,41), massa da materia seca das raizes (0,079) e parte aerea (0,229), os valores maximos foram obtidos quando as sementes foram submetidas a secagem por 44; 33 e 50 horas, respectivamente. Diante dos resultados, recomenda-se a secagem de sementes de pitombeira por ate 48 horas, como forma de garantir a germinacao e o vigor.

Rendimento de maxixe adubado com doses de nitrogênio

The effect of increasing nitrogen doses was evaluated on the gherkin yield, cv. Nordestino. This study was carried out on the period from May to September 2006, at the Universidade Federal da Paraiba, in Areia, Paraiba State, Brazil, in an experimental design of randomized blocks with six treatments (0; 50; 100; 150, 200 and 250 kg ha-1 N) and four replications. Twenty plants per plot were used, on a spacing of 2 x 1 m. Fruit average mass, number and fruits production per plant, and yield of fruits were evaluated. Fruits average mass reached the maximum value of 21 g using the dose of 155 kg ha-1 of N. The maximum number (21 fruits) and the maximum fruits production per plant of gherkins (469 g) were reached with 153 and 187 kg ha-1 of N, respectively. The dose of 188 kg ha-1 of N was responsible for the maximum yield of 12.7 t ha-1 of fruits. For the highest maximum economic efficiency the dose of 183 kg ha-1 of N was responsible for the yield of 12.7 t ha-1 of commercial fruits, meaning a development of 9.4 t ha-1 in the fruits productivity, relative to N absence.

Profundidades de semeadura para emergência de plântulas de juazeiro

Zizyphus joazeiro Mart. is a typical Brazilian tree of the northeastern dry lands, being endemic to the Caatinga. It occurs in various states of Northeast Brazil and provides a great economic potential and importance for this semi-arid region. This study had as objective to determine the best sowing depth of Zizyphus joazeiro. In greenhouse sand substratum, with 4 replications of 25 units of dispersion each one, in the following depths (one, too, tree, four and five centimeters). It was ended that the sowing of juazeiro in nursery should be done in the depth of 1.0 to 1.6cm. The depth of 1 cm resulted in smaller time for the total germination.