Germination of Syzygium malaccense and Syzygium jambos seeds under different thermal conditions and seedling morphology

Abstract The objective of this research was to analyze the influence of temperature on seed germination and seedling morphology for the S. malaccense and . S. jambosFor germination, 250 seeds of each species, of ripe fruits, were used, which were washed in running water, dried in room condition for 24 hours and disinfected. The seeds were placed in plastic boxes with medium texture vermiculite substrate and submitted to different temperatures: 20, 25, 30, 35ºC and 20-30°C in BOD`S, in a completely randomized design. The variables analyzed were: daily germination percentage, polyembryony and GSI. For morphological characterization, 30 seeds of both each species, submitted to a temperature of 30oC and samples were collected at intervals representative of the germination. There is no influence of temperature on the germination of S. malacense seeds and for S. jambos there are losses of 35oC. The temperatures of 25 20-30 and 30oC, influence the highest percentage of polyembryony for S. malaccense, for S. jambos, only the temperature of 35oC affected this process. The temperatures of 20 and 25oC decreased the GSI, for both species. The seeds have green cotyledons, hypogeal germination with brown primary root and whitish, short and filiform secondary roots.

Download Full-text

Physiological quality of osmoprimed eggplant seeds

Ciência e Agrotecnologia ◽

10.1590/s1413-70542012000500005 ◽

2012 ◽

Vol 36 (5) ◽

pp. 526-532 ◽

Cited By ~ 4

Author(s):

Rodrigo de Góes Esperon Reis ◽

Renato Mendes Guimarães ◽

Antônio Rodrigues Vieira ◽

Nayara Roberto Gonçalves ◽

Valéria Hanny Costa

Keyword(s):

Initial Moisture Content ◽

Germination Percentage ◽

Central Laboratory ◽

Seed Vigour ◽

Running Water ◽

Randomized Design ◽

Physiological Quality ◽

Completely Randomized Design ◽

Cold Chamber

Eggplant seeds germination can be slow and uneven, justifying the use of pre-germinative treatments to improve the performance of seed lots. One option of treatment is the controlled hydration of seeds by priming. In this way, this study aimed to evaluate the performance of eggplant seeds cv. Embu submitted to different methodologies of priming. The seeds used in the experiment were stored in cold chamber (15º C and 55% RH) in paper bags. The research was carried out at Central Laboratory of Seeds/UFLA. The seeds were submitted to the priming in aerated solutions varying the following factors: temperature (15º C and 25º C), time (24, 48 and 72 hours) and solution (water, PEG, KNO3 and PEG+KNO3). Seeds were washed in running water and dried at 30º C, until the return to the initial moisture content, around 10%. The variables analyzed were percentage of germination, percentage of emergence, speed index of emergence and electrical conductivity. The treatments were arranged in a completely randomized design, according to a factorial arrangement 2x3x4+1 (control - seeds without priming). The results showed that priming improves the vigour of eggplant seeds with no effect on viability; the priming in water or KNO3 is efficient to improve the seed vigour and priming in water or KNO3 may use temperature of 15º C or 25º C for 24, 48 or 72 hours.

Download Full-text

Morphological characterization of fruit, seed and seedling and germination of Hymenaea courbaril L. (Fabaceae) ('Jatobá')

Journal of Seed Science ◽

10.1590/2317-1545v38n3159734 ◽

2016 ◽

Vol 38 (3) ◽

pp. 204-211 ◽

Cited By ~ 1

Author(s):

Manoela Mendes Duarte ◽

Sheilly Raquelly Prado de Paula ◽

Flaick Rodrigo de Lima Ferreira ◽

Antonio Carlos Nogueira

Keyword(s):

Germination Percentage ◽

Morphological Characterization ◽

Morphological Description ◽

Hymenaea Courbaril ◽

Randomized Design ◽

Early Seedling ◽

Mean Germination Time ◽

Completely Randomized Design ◽

Early Seedling Development

Abstract This study has aimed to characterize the morphology of fruit, seed and seedling and evaluate the germination of Hymenaea courbaril L., under different substrates and temperatures. The physical characteristics were determined, as well as the morphological description of the internal and external parts of fruits and seeds, stages of germination and early seedling development. Germination tests were conducted in a completely randomized design, in a 3x2 factorial scheme, with three temperatures (20 °C, 25 °C and 30 °C) and two substrates (sand and vermiculite), with six plots of 30 seeds. The germination percentage, germination speed index (GSI) and mean germination time (MGT) were calculated. The fruits are dry and woody and the seeds are exalbuminous, with an axial embryo. The germination is epigeal and the seedling is phanerocotylar. The combination of vermiculite or sand associated to temperatures of 25 °C or 30 °C is effective for conducting the germination tests.

Download Full-text

TECHNOLOGICAL PARAMETERS OF SEEDS APPLIED TO THE SELECTION OF SUPERIOR MOTHER TREES FROM Ormosia discolor SPRUCE EX BENTH

Revista Árvore ◽

10.1590/1806-908820210000036 ◽

2021 ◽

Vol 45 ◽

Author(s):

Helinara Lais Vieira Capucho ◽

Manuel de Jesus Vieira Lima Júnior ◽

Angela Maria da Silva Mendes ◽

Maria Teresa Gomes Lopes ◽

Amazoneida Sá Peixoto Pinheiro ◽

...

Keyword(s):

Water Content ◽

Native Species ◽

Primary Root ◽

Seed Storage ◽

Germination Percentage ◽

Technological Parameters ◽

Physical Dormancy ◽

Randomized Design ◽

Nodulation Capacity ◽

Selection Of

ABSTRACT The study on the native species of fast growth and nodulation capacity, Ormosia discolor, intends to conserve genetic resources and make available seed lots of high vigor for seed orchards. This work evaluates the physical and physiological characteristics of seeds from 20 O. discolor trees as a subsidy for selecting superior mother trees. Twenty matrices selected from a population in the state of Amazonas were inventoried. Physical tests were performed on the seeds collected, including water content, biometrics, the weight of one thousand seeds, and coat permeability test. For vigor estimates and classification regarding seed storage, the seeds were frozen for five months. The germination test was carried out at a constant temperature of 30 °C. It was used a completely randomized design consisting of 20 mother trees, 4 replicates, and 25 seeds per plot. The germination characteristics evaluated were germination percentage, speed index, mean germination time, and synchronization index. Cut seeds are more efficient for determining water content. All biometric variables are representative for the selection of vigorous lots, with emphasis on geometric diameter, surface area, and sphericity of seeds. Species seeds were classified as orthodox and as having physical dormancy. The protrusion of the primary root is the best morphological characteristic for evaluating germination in the laboratory. The mother trees 7, 16, and 10 showed superior characteristics for dendrometric and technological data, being indicated for marking, phenological monitoring, and planting.

Download Full-text

ALLELOPATHIC EFFECT OF Sorghum bicolor AND Digitaria insularis ON GERMINATION AND INITIAL DEVELOPMENT OF CANOLA

JOURNAL OF NEOTROPICAL AGRICULTURE ◽

10.32404/rean.v7i4.4230 ◽

2020 ◽

Vol 7 (4) ◽

pp. 65-72

Author(s):

Thiago Souza Campos ◽

Ane Gabriele Vaz Sousa ◽

Jaime Santos do Rego Junior ◽

Westefann Dos Santos Sousa ◽

Cleiton Gredson Sabin Benett ◽

...

Keyword(s):

Sorghum Bicolor ◽

Abiotic Factors ◽

Primary Root ◽

Germination Percentage ◽

Allelopathic Effect ◽

Brassica Napus L ◽

Initial Development ◽

Randomized Design ◽

Allelopathic Effects ◽

Completely Randomized Design

Agriculture depends on biotic and abiotic factors, and one of them is allelopathy, defined as the chemical interference that one plant has on others, which can negatively affect germination. The objective of this work is to evaluate the allelopathic effects of Sorghum bicolor and Digitaria insularis on seed germination and initial development of canola seedlings (Brassica napus L.). A completely randomized design was used in a 2x5 factorial scheme (two extracts: D. insularis and S. bicolor) and five concentrations (0, 25, 50, 75, and 100%), with four replicates of fifty seeds, the plot being constituted by a 'gerbox' box containing 50 seeds evenly distributed. The variable analyzed were germination percentage (G), abnormal seedlings (AS), dead seeds (DS), length of the shoot (SL) and primary root (RL), total length (TL) of the seedling, shoot ratio (S/T), and root ratio (R/T). The aqueous extracts of D. insularis interfere in all variables studied, which compromises the formation of normal seedlings, regardless of concentration. The extract of S. bicolor expressed allelopathic effects only in concentrations above 75%. Both species can inhibit the initial development of canola plants.

Download Full-text

The effect of temperature on high-resolution TEM image contrast

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139573 ◽

1995 ◽

Vol 53 ◽

pp. 640-641

Author(s):

T. Geipel ◽

W. Mader ◽

P. Pirouz

Keyword(s):

Form Factor ◽

Inelastic Scattering ◽

Accurate Method ◽

Waller Factor ◽

Effect Of Temperature ◽

Specimen Thickness ◽

Influence Of Temperature ◽

Debye Waller Factor ◽

Influence Of Temperature On ◽

Atomic Form Factor

Temperature affects both elastic and inelastic scattering of electrons in a crystal. The Debye-Waller factor, B, describes the influence of temperature on the elastic scattering of electrons, whereas the imaginary part of the (complex) atomic form factor, fc = fr + ifi, describes the influence of temperature on the inelastic scattering of electrons (i.e. absorption). In HRTEM simulations, two possible ways to include absorption are: (i) an approximate method in which absorption is described by a phenomenological constant, μ, i.e. fi; - μfr, with the real part of the atomic form factor, fr, obtained from Hartree-Fock calculations, (ii) a more accurate method in which the absorptive components, fi of the atomic form factor are explicitly calculated. In this contribution, the inclusion of both the Debye-Waller factor and absorption on HRTEM images of a (Oll)-oriented GaAs crystal are presented (using the EMS software.Fig. 1 shows the the amplitudes and phases of the dominant 111 beams as a function of the specimen thickness, t, for the cases when μ = 0 (i.e. no absorption, solid line) and μ = 0.1 (with absorption, dashed line).

Download Full-text