Physical and physiological changes of Crambe abyssinica Hochst seed during maturation

Determination of seed-maturation indicators enables the identification of the ideal moment for harvest to achieve the best production and conservation potential. Our objective here was to evaluate some physical and physiological changes of crambe (Crambe abyssinica Hochst) seeds as possible indicators of seed maturation. Crambe flowering was monitored in Dourados, Mato Grosso do Sul, Brazil. Plants were tagged, and 13, 22, 26, and 28 days after the initiation of flowering, the seeds were collected and following physical attributes evaluated: length, diameter, total mass, dry matter and water content. Physiological quality of the seeds was assessed using the germination test, by registering the percentage of normal seedlings and dormant seeds, immediately after each harvest, and again after six months of storage. The water-absorption curves were characterized as a function the seed-development stages. All physical attributes were observed to increase because of the accumulation of reserve substances during seed development, except for water content, which gradually decreased from 72.2% at the start of development to 29.5% at maturity. At 28 days after anthesis the germination percentage of crambe seeds at physiological maturity was only 17%, indicating that they became dormant while maturing. However, seed germination rate was 89% after six months of storage, indicating that dormancy was almost fully overcome after this period.

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Thermal stress and physiological changes in watermelon seeds

Pesquisa Agropecuária Tropical ◽

10.1590/1983-40632018v4850404 ◽

2018 ◽

Vol 48 (1) ◽

pp. 66-74 ◽

Cited By ~ 1

Author(s):

Rita de Cássia Barbosa da Silva ◽

Marcelo do Nascimento Araujo ◽

Fábio Luiz Santos Ornellas ◽

Bárbara França Dantas

Keyword(s):

Enzyme Activity ◽

Thermal Stress ◽

Germination Rate ◽

Germination Percentage ◽

Initial Growth ◽

Physiological Changes ◽

Percentage Germination ◽

Stress Protection ◽

Evaluation Parameters ◽

The Ideal

ABSTRACT Given that watermelon is a crop widespread around the world, there is considerable interest in verifying how its seeds physiologically behave under unfavorable temperature conditions. This study aimed to evaluate the biochemical changes mobilization and reserves degradation, as well as the enzyme activity, during seed germination and initial growth of watermelon seedlings subjected to thermal stress, using temperature, germination percentage, germination rate and relative germination frequency over the incubation time as evaluation parameters. The experimental design was completely randomized, in a 5 x 3 factorial scheme, with five temperatures (17 ºC, 20 ºC, 25 ºC, 30 ºC and 35 ºC) and three cultivars (Charleston Gray, Fairfax and Crimson Sweet), with 4 replicates of 50 seeds. Germination, seedling growth, reserve degradation and stress protection system were evaluated. Thermal stress caused deleterious effects on watermelon seeds with germination capacity at well defined temperature limits, being 25 ºC the ideal temperature, with the highest percentage of normal seedlings. Sub- (17 ºC) and supra-optimal (30 ºC) temperatures presented more than 80 % of abnormal seedlings. The α-amylase enzyme activity is intense only at the beginning of germination. Under thermal stress, the proline contents increase mainly in the cotyledons.

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Morphological and germination response variability in seeds of wild yellow gentian (Gentiana lutea L.) accessions from northwest Spain

Botany ◽

10.1139/b2012-028 ◽

2012 ◽

Vol 90 (8) ◽

pp. 731-742 ◽

Cited By ~ 8

Author(s):

Félix Pérez-García ◽

Federico Varela ◽

M. Elena González-Benito

Keyword(s):

Seed Germination ◽

Water Content ◽

Germination Rate ◽

Seed Mass ◽

Germination Percentage ◽

Gentiana Lutea ◽

Moist Chilling ◽

Mean Germination Time ◽

Wild Accessions ◽

Seed Water Content

Gentiana lutea L. (yellow gentian, Gentianaceae) is an important medicinal plant under protection as endangered species in most European countries. The aim of this work was to evaluate variation in seed mass, seed water content, and seed germination among 56 wild accessions of G. lutea. The effect of gibberellic acid (GA3), putrescine, moist chilling, and level of ripeness of seeds on subsequent germination was also investigated. Seeds of G. lutea showed physiological dormancy (final germination percentages ranged from 0% to 11%, depending on the accession) and GA3 enhanced seed germination drastically in all the accessions. The highest germination (99%) of GA3-treated seeds was reached at 15 °C. Final germination percentage and germination rate (as expressed by mean germination time), as well as seed mass and seed water content, varied significantly among accessions. In general, 1 year moist chilling did not significantly enhance G. lutea seed germination. For most accessions, no significant differences were found between fully ripe seeds and less ripe seeds for seed water content, seed mass, and seed germination. Applications of GA3 were always most effective than those of putrescine for increasing seed germination.

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Physiological ripening of Anadenanthera colubrina (Vellozo) Brenan seeds

Journal of Seed Science ◽

10.1590/2317-1545v38n2153112 ◽

2016 ◽

Vol 38 (2) ◽

pp. 155-161 ◽

Cited By ~ 1

Author(s):

Paulo Affonso Fonseca Pires Neto ◽

Victória Campos Monteiro Pires ◽

Cristiano Bueno Moraes ◽

Lucicleia Mendes de Oliveira ◽

Augustus Caeser Franke Portella ◽

...

Keyword(s):

Water Content ◽

Dry Matter ◽

Primary Root ◽

Germination Percentage ◽

Fruit Weight ◽

Maximum Dimension ◽

Physiological Maturity ◽

Maximum Value ◽

Physiological Quality ◽

The Ideal

Abstract: The seed physiological maturity knowledgment is critical determine its maximum production and physiological quality. The objective of this study was to determine the ideal time to harvest by evaluating seeds physiological maturity. Seventeen weekly harvests of fruits and seeds from matrices located in the Brazilian city of Botucatu, SP, were performed from May to September 2001. Fruits size and weight, seed water content and dry matter, and germination and emission of primary root were evaluated. Seeds showed maximum dimension in the thirteenth week of collection, while the highest fruit weight was obtained in the twelfth week of collection. Water content decreased over time. Seeds dry matter showed its highest value in the sixteenth week harvest, while germination percentage showed its highest value between the fourteenth and fifteenth week harvest. The percentage of primary root emission was observed with maximum value in the tenth week harvest. Based on the results, it is concluded that the best Anadenanthera colubrina harvest season occurs between the fourteenth and fifteenth weeks.

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Seed physiological quality and harvest point of dovyalis fruits

Pesquisa Agropecuária Tropical ◽

10.1590/1983-40632019v4954520 ◽

2019 ◽

Vol 49 ◽

Author(s):

Fabíola Villa ◽

Daniel Fernandes da Silva ◽

Maria Cristina Copello Rotili ◽

Neusa Francisca Michelon Herzog ◽

Marlene de Matos Malavasi

Keyword(s):

Seed Quality ◽

Biomass Accumulation ◽

Germination Percentage ◽

Propagation Mode ◽

Yellowish Green ◽

Statistical Variation ◽

Stage 4 ◽

Physiological Quality ◽

Physical Attributes ◽

Stage 1

ABSTRACT The main propagation mode of dovyalis is by seeds, what makes important to determine the ideal moment of fruit harvest. This study aimed to evaluate the physiological seed quality and harvest time of dovyalis fruits. To determine the fruit physical attributes, they were visually classified into five classes, according to the maturity stages, based on the external color of the exocarp: stage 1: green fruit; stage 2: yellowish-green; stage 3: yellowish-brown; stage 4: brown; stage 5: intense brown. The seed extraction to evaluate the physiological quality was based on the seed water content, germination percentage, germination speed index and determination of the dry biomass of the shoot, root and seedlings originated from these seeds. The experimental design was completely randomized, containing 25 seeds per treatment and 4 replicates. The fruit color during ripening varies from green to intense brown. The fruits reach their largest size and fresh biomass accumulation in the stage 4, with the brown exocarp color represented in the Munsell chart by 2.5YR 3/4. The removal of seeds for propagation should occur from the stage 2 (2.5GY 5/8), when the fruits have a yellowish-green color, although no statistical variation is observed in the number of seeds during maturation.

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Interactive Influence of Location and Variety on Physiological Quality of Cowpea Seeds (Vigna unguiculata (L) Walp.)

Journal of Agriculture and Ecology Research International ◽

10.9734/jaeri/2021/v22i430194 ◽

2021 ◽

pp. 20-25

Author(s):

F. E. Awosanmi ◽

M. Ogunleye ◽

G. O. Awosanmi ◽

B. S. Olisa ◽

S. A. Ajayi

Keyword(s):

Electrical Conductivity ◽

Seed Weight ◽

Germination Rate ◽

Germination Percentage ◽

Accelerated Ageing ◽

Percentage Germination ◽

Production Environment ◽

Cowpea Seeds ◽

Physiological Quality

The production environment plays a significant role in the production of high-quality seeds. Therefore, the knowledge of the relative contributions of the different factors that impact seed quality will be important for the management of seed production. The objective of this study was to assess the relative contribution of location and variety to the physiological quality of the cowpea seeds. Seeds of two varieties of cowpea, IT97K-918-118 and 977K-1499-35 were produced at three locations: Ikenne, Ilora, and Ballah. Hundred seed weight, seed moisture content, standard germination, accelerated ageing germination and electrical conductivity tests were carried out on the seeds. The results indicated that the location effect was highly significant (P<0.05) for hundred seed weight, germination percentage, germination rate index, accelerated ageing germination percentage and accelerated ageing germination rate index, while the varietal effect was highly significant for only hundred seed weight. However, location alone contributed more than 50% to the observed variability in hundred seed weight, germination percentage, germination rate index and accelerated ageing germination percentage. Seeds from Ballah had the highest viability (germination percentage = 84.67%) but also the lowest vigour (accelerated ageing germination = 11%; electrical conductivity = 64.10µscm-1g-1). Thus, the modulating effect of the environment on the quality of cowpea seeds is not the same for the different components of quality and the choice of location for the production of cowpea seeds should be given a higher priority than a choice of variety per se.

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Effects of Water supply on Seed Development and Quality of Chickpea Cultivars

Plant Breeding and Seed Science ◽

10.2478/v10129-011-0068-0 ◽

2014 ◽

Vol 67 (1) ◽

pp. 37-44

Author(s):

Kazem Ghassemi-Golezani ◽

Saeid Ghassemi

Keyword(s):

Water Supply ◽

Seed Weight ◽

Seed Quality ◽

Germination Rate ◽

Dry Weight ◽

Germination Percentage ◽

Genetic Constitution ◽

Physiological Quality ◽

Chickpea Cultivars

AbstractA split plot experiment (using RCB design) with three replications was conducted in 2012 and seed physiological quality of three chickpea (Cicer arietinumL.) cultivars (Azad, Arman and Jame) was evaluated at seven stages under well and limited irrigation conditions. Maximum seed weight (mass maturity) was achieved at 40–45 days after flowering. However, maximum seed quality was obtained 7 to 10 days after mass maturity, depending on irrigation intervals and cultivars. At earlier harvests, because of immaturity, and at later harvests, due to ageing, seed quality was low. Seed filling rate and maximum seed weight of chickpea decreased with decreasing water supply, but water deficit had no significant effects on seed quality as measured by germination percentage, germination rate and seedling dry weight. Significant differences in seedling dry weight among chickpea cultivars were attributed to significant variation in seed weight affected by genetic constitution.

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Phytotoxicity of exotic species on the physiological potential of crambe seeds (Crambe abyssinica Hochs)

Revista Agro mbiente On-line ◽

10.18227/1982-8470ragro.v12i1.4329 ◽

2017 ◽

Vol 12 (1) ◽

pp. 89

Author(s):

Silvana Fraga Silva ◽

Halina Stéffany Lopes Costa ◽

Jesimiel Silva Viana ◽

Sebastião Medeiros Filho

Keyword(s):

Exotic Species ◽

Germination Rate ◽

Dry Mass ◽

Control Treatment ◽

Allelopathic Effect ◽

Aqueous Extracts ◽

Crambe Abyssinica ◽

Seedling Length ◽

Physiological Quality ◽

Cultivated Species

Biological invasions of exotic plants can seriously contribute to ecological imbalances within areas to which they have been introduced, affecting, in addition to native plants, cultivated species. Consequently, the objective of the current study was to evaluate effects of allelopathic extracts of three exotic species on the physiological quality of crambe seeds. Aqueous extracts of Prosopis juliflora (Sw.) DC (algaroba) were formulated; Azadirachta indica A. Juss (Nim) and Cryptostegia madagascariensis Bojer ex Decne (viuvinha) at 20% (200 g of dried leaves per liter of distilled water) placed in B.O.D at 25 ° C for 24 h. Petri dishes, lined with germitest paper sheets, were moistened with aqueous extracts at 2,5 times de paper weight. In the experimental trial, we used the completely randomized, with four treatments (three extracts + control treatment) and four replicates of 25 seeds. The first and second germination counts were evaluated in the fourth and tenth days respectively; germination rate index (GRI), allelopathic effect index (AEI), seedling length and dry mass. P. juliflora and C. madagascariensis reduced germination by 84 and 91%, respectively, in the first count. The GRI was affected by the three species, while the AEI showed greater allelopathy for C. madagascariensis, reaching -0.90. Seedlings lengths were reduced in the presence of P. juliflora and C. madagascariensis. For crambe seeds, all extracts negatively affected their physiological potential.

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Desiccation of Pachira aquatica Aubl. Seeds

Journal of Agricultural Science ◽

10.5539/jas.v10n11p553 ◽

2018 ◽

Vol 10 (11) ◽

pp. 553

Author(s):

Amanda Araújo Lima ◽

Edilma Pereira Gonçalves ◽

Jeandson Silva Viana ◽

Priscila Cordeiro Souto ◽

Débora Teresa da Rocha Gomes Ferreira ◽

...

Keyword(s):

Water Content ◽

Native Species ◽

Seed Quality ◽

Germination Rate ◽

High Water ◽

High Water Content ◽

Small Reduction ◽

Drying Temperature ◽

Before And After ◽

Physiological Quality

The conservation of seed quality during storage is important to perform the maintenance and conservation of germplasm banks. Several native species of Brazil are intolerant to desiccation to desirable levels for conservation during storage is necessary to develop specific technologies for their conservation. The objective of this research was to evaluate the physiological quality of Paquira aquatica seeds submitted to drying periods. The study was carried out using seeds of P. aquatica dried at a temperature of 35 ºC, the following exposure times: 0 (no drying), 24, 48, 72 and 96 hours. Before and after each period of drying samples for the evaluations, the data were submitted to analysis of variance and regressionat level of 5%. The seeds of P. aquatica were dispersed with very high water content and a small reduction in its physiological value agrees quality, allowing the seeds to characterize this as a recalcitrant species. The drying temperature is 35 ºC until the viable 24 hours after this period the water content of seed reduced from 55% to 43%, which was considered the critical level for desiccation of seeds of P. aquatica. Because it reduces the values of first count, germination, rate of germination and growth of seedlings.The drying temperature the 35 ºC until the viable 24 hours, whit small reduction in its physiological quality seed P. aquatica.

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Impact of phytopathogens on seed quality of tropical grasses in integrated systems

Australian Journal of Crop Science ◽

10.21475/ajcs.21.15.03.p2375 ◽

2021 ◽

pp. 312-318

Author(s):

Anne Caroline Dallabrida Avelino ◽

Dayana Aparecida de Faria ◽

Wender Mateus Peixoto ◽

Elisangela Clarete Camili ◽

Virgínia Helena de Azevedo ◽

...

Keyword(s):

Seed Quality ◽

Germination Rate ◽

Accelerated Aging ◽

Germination Percentage ◽

Integrated Systems ◽

Experimental Conditions ◽

Open Design ◽

Brachiaria Ruziziensis ◽

Tropical Forage ◽

Physiological Quality

This study aimed to identify the main fungal and phytonematode genotypes associated with the main tropical forage seeds used in integrated systems and to distinguish seeds with high physiological and sanitary quality, for which two experiments were conducted. In year 1 (2017/18 crop year), the first experiment (experiment 1) was conducted with seeds produced in the 2017/18 crop year, in a randomized open design with four configurations and four replications. In year 2 (2018/19 crop year), the study (experiment 2) was replicated with the experimental conditions of the first experiment (randomized automatic design, with four sessions and four replications), but using samples from the 2018/19 crop year. The seeds were produced in the 2017/18 and 2018/19 crop years, with the same origin, and were purchased within commercial packages. The treatments of experiments 1 and 2 were the same and consisted of seeds of Brachiaria ruziziensis and the Brachiaria brizantha cultivars Marandu, Xaraés, and BRS Piatã. The same variables were evaluated for each experiment: water content, physical purity, viability, germination rate index, first germination count, germination percentage, crop value, dormancy, accelerated aging, and incidence of fungi and phytonematodes. Cladosporium sp., Fusarium sp., Rhizoctonia sp., Meloidogyne sp., Filenchus sp., Aphelenchus sp., Aphelencoides sp., and Rotylenchulus sp. are the main phytopathogens associated with seeds of the main tropical forage species used in integrated systems. The seeds of B. ruziziensis present high physiological quality, whereas the seeds of the B. brizantha cultivar Xaraés grass present high sanitary quality

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Effect of Tree Spacing, Cone Storage, and Prechilling on Germination of Picea glauca Seed

The Forestry Chronicle ◽

10.5558/tfc66388-4 ◽

1990 ◽

Vol 66 (4) ◽

pp. 388-392 ◽

Cited By ~ 6

Author(s):

G. E. Caron ◽

B. S. P. Wang ◽

H. O. Schooley

Keyword(s):

Seed Dormancy ◽

Seed Yield ◽

Picea Glauca ◽

Seed Weight ◽

Germination Rate ◽

Germination Percentage ◽

Seed Maturation ◽

Percentage Germination ◽

Seed Extraction ◽

Production Area

Cones were collected in 1984 at the time of natural seed dissemination from 18 open-pollinated, 30-year-o!d white spruce (Picea glauca(Moench) Voss) trees at 1.2, 2.4, and 4.9 m spacings in a demonstration seed production area at Petawawa National Forestry Institute. Cones were stored in a well-ventilated building for 2 to 6 weeks before seed extraction.Cones length, full-seed-yield per cone, and full-seed weight were greatest for cones collected from trees at the 1.2 m spacing. When cones were stored for 2 weeks, non-prechilled and prechilled seeds averaged 32.0 ± 1.0% [Formula: see text] and 62.3 ± 1.0% germination, respectively. When cones were stored for 6 weeks, non-prechilled and prechilled seeds averaged 61.3 ± 1.2% and 94.7 ± 0.5% germination, respectively. The higher germination percentage, germination rate, and lower tree to tree variation for prechilled seeds from cones stored for 6 weeks indicate that seed maturation was promoted by post-harvest cone storage prior to seed extraction. Average seed dormancy remained about the same from 2 to 6 weeks of storage; however, seeds from some trees became more dormant with the storage whereas those from others became less dormant. Relationship between seed weight and germination was weak. Key words: Cone storage, seed prechilling, germination percentage, germination rate, seed maturation, seed dormancy, seed weight, seed sorting.

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