Célia Maria Peixoto de Macedo

Tratamentos para acelerar a germinação e reduzir a deterioração das sementes de Ormosia nitida Vog

The experiment was carried out at the Seed Laboratory of the Agronomy Center of the Federal University of Espirito Santo, in order to attain acceleration of germination and reduce seed deterioration in Ormosia nitida Vog.. A completely randomized experimental design with four replications was used. In experiment I, with paper substratum, the treatments were intact seeds (control); mechanical scarification and sulfuric acid soaking for 10 minutes. In experiment II, in Petri dishes, the treatments were intacts seeds (control); mechanical scarification; mechanical scarification + soaking in water at 35oC for 24 hours; imbibition of germination substratum with H2O2; sulphuric acid soaking for 1; 5; 10; 15; 20; 25 and 30 minutes. The results showed higher synchronization and speed germination in treatments with mechanical scarification, sulphuric acid for 10 minutes and H2O2 in the substratum.

Germinação de sementes de couve chinesa sob influência do teor de água, substrato e estresse salino

This work evaluated seed germination and vigor of Brassica pekinensis cv. granat as affected by moisture content, substrate and saline stress. The experiment was carried out at the Seed Laboratory of the Agrarian Center Science of Universidade Federal do Espirito Santo, in Alegre-ES, in a completely randomized design with the treatments distributed in a 2x3x5 factorial scheme to test the influence of seed moisture content (8 and 16%), substrate (top of sand, top of paper and between paper) and four NaCl solution concentrations (-0.2; -0.4; - 0.6 e -0.8 MPa). Germination test was performed at 20-30°C. The following parameters were considered: percentage and speed of germination, seedling fresh and dry weight. Percentage and speed of germination in a top of paper sowing was higher for the 8% M.C. seed lot. Seed germination and vigor decreased as salt concentrations increased. The seeds of 16% M.C. sown at top of sand and between paper, with salt solution of -0.2 and -0.4 MPa showed increases in seedling fresh weight, while significant increase of dry weight was observed at -0.8MPa. In conclusion, salinity is deleterious to Brassica pekinensis seed performance and damages are proportional to decrease of the osmotical potential. Seeds showed to be more tolerant to water deficit durning the initial stages of plant development.

Germinação e vigor de sementes de urucu

This research was carried out to evaluate the germination and vigor of annatto seeds (Bixa orellana L.) during maturation, collecting samples 70, 77, and 84 days after anthesis (DAA). The research consisted of two phases: first, seed samples of each harvest were submitted to different treatments: (i) mechanical scarification; (ii) thermotherapy (70oC in water bath) for 1, 2, and 3 min; (iii) pre-chilling at 3oC during seven days, using distilled water or KNO3 solution to moist the paper towel, and untreated intact seeds (control). In the second phase, seed samples (70, 77, and 84 DAA) were submitted to accelerated aging (AA) (42oC, 100% relative humidity) for 0, 12, 24, 36, 48, 60, 72, 84, and 96 hours. In both phases, seeds were sub sampled for evaluation. The germination of intact seeds collected 70, 77, and 84 DAA was 51, 53, and 16%, respectively, and thermotherapy was the only treatment that significantly altered it. Although hindering the germination of seeds collected 70 DAA, thermotherapy for 1 and 3 minutes enhanced germination in seeds collected 84 DAA (62 and 55%, respectively). In intact seeds, the germination rate (GR) of seeds collected 84 DAA (0.51) was significantly lower than in seeds collected 70 (1.90) and 77 DAA (2.32). However, thermotherapy significantly increased GR for seeds collected at 84 DAA (1.65, 3.03, 1.83, respectively for 1, 3, and 5 minutes of immersion), which suggests the occurrence of dormancy after the alleged physiological maturation point (84 DAA). For seeds collected 70 DAA, accelerated aging (AA) up to 96 hours did not interfered in germination. For seeds collected 77 and 84 DAA, germination decreased as exposure time to AA increased. Seeds collected 70 DAA had the highest proportion of regular seedlings.

QUALIDADE FISIOLÓGICA DE SEMENTE DE CAFÉ ARÁBICA NA PRESENÇA DE ALUMÍNIO 1

The objective of this study was to evaluate the germination and vigor of the seed of Coffea Arabica L., cultivars Catuai Amarelo IAC 62, Obata, Oeiras, and IAPAR 59, in the presence of aluminum. A completely random design was used with four replications, in a 4 x 2 factorial outline, corresponding to the four cultivars and the absence and presence of Al in the form of Al2(SO4)3.16H2O, at the concentration of 45 mg.L-1,. The seeds were placed to germinate in paper-towel, incubated at 30 °C without light. There was no significant interaction between cultivars and aluminum. Among the studied cultivars, Catuai Amarelo (IAC 62) was found to be the one with the most sensitive seeds to aluminium. The germination of the seeds of the studied cultivars was not affected by the concentration of 45 mg.L-1 of Al3+. However, at that Al+3 concentration, the growth of the primary root of the four cultivars was observed to be stimulated.

Tolerance of arabica coffee cultivars for aluminum in nutritive solution

This work aimed to evaluate the Coffea arabica cultivars for aluminum toxicity tolerance, in modified Hoagland solution. A completely randomized design with five repetitions in a factorial 4 x 4 (cultivar x combinations of aluminum) was used. After 44 days of the sowing, were transferred ten seedlings each cultivar germinated in the absence of Al3+ to solution without Al3+, and ten for solution with Al3+; ten seedlings each cultivar germinated in presence of Al3+ to solution without Al3+, and ten for solution with Al3+. In the treatment with aluminum, the element was added to the nutritive solution in the concentration of 0.83 mmol L-1 as Al2(SO4)3.16H2O. The cultivars Catuai Amarelo IAC 62 and Iapar 59 were tolerant to the aluminum; cultivar Oeiras presented intermediate tolerance, while cultivar Obata IAC 1669-20 was sensitive. The tolerance of the coffee cultivars to the aluminum during the initial development of the seedlings did not depend on the presence of aluminum in the germination phase.

Brotação de mamoeiro tainung 1 submetido a diferentes alturas de corte do caule

This work was carried out at greenhouse, in the CCA-UFES, Alegre-ES and had as an aim to study the effect of different heights of cut of stem in sproution of papaya plants Tainung 01 (Carica papaya L.). The work was carried out in two phases, utilizing plants with age of 190 days cultivated in polyethylene containers of 1288 cm3. In the first phase, the experimental design was in completely randomized design, with three treatments and 14 replications of one plant per plot: plants cutting with 20; 35 e 50 cm of height, measured from the plant lap. After 30 days of cut of the stem, they evaluated the next agronomical characteristic: last shoot diameter, last shoot size, last shoot leaf number larger one centimeter and shoot number for plant. In this first phase, the last shoot size was the characteristic that introduced significant difference. In the second phase, last shoots of plants utilized in the previous phase were removed. The experimental design was in completely randomized design with 13 repetitions in split plot, with the primary treatments of the previous phase and in split plot was made an evaluation in the first one and at 15 and 30 days. The agronomical characteristic evaluated was the same of the first phase. The cutting at 20 cm height provides better last shoot development and increase of the leaf number in the last shoot.