Germination of Stewartia pseudocamellia Seeds is Promoted by Desiccation Avoidance, Gibberellic Acid Treatment, and Warm and Cold Stratification

Abstract Japanese Stewartia, Stewartia pseudocamellia (Maxim.), seeds were extracted from immature capsules and handled under nondesiccating conditions. Moisture content of fresh seeds was 82%. After exposing seeds for 48 hrs at room conditions seed moisture content was 56% and after 24 hrs at 80C (176F) it was 49%. Both ambient and 80C (176F) drying conditions resulted in complete loss of viability based on a tetazolium test. Exposing seeds to a 24 hr aerated water soak in 1 mM gibberellic acid (GA3), and a 3 month warm (25C, 77F) stratification period increased seed germination only after 6 months of cold (4C, 40F) stratification compared to seeds given a 24 hr aerated water soak without GA3 and similar warm and cold stratification periods. Best management practices for handling and germination of fresh Japanese Stewartia seeds are: (a) harvest seed capsules when they turn from green to brown, (b) maintain seeds under nondesiccating conditions, (c) treat seeds with a 24 hr aerated water soak in 1 mM GA3 before a 3-month warm stratification, and (d) provide at least 7 months cold stratification.

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Physiological behaviour of Blepharocalyx salicifolius and Casearia decandra seeds on the tolerance to dehydration

Journal of Seed Science ◽

10.1590/s2317-15372013000300008 ◽

2013 ◽

Vol 35 (3) ◽

pp. 323-330 ◽

Cited By ~ 1

Author(s):

Suelen Santos Rego ◽

Antonio Carlos Nogueira ◽

Antonio Carlos de Souza Medeiros ◽

Carmen Lúcia de Oliveira Petkowicz ◽

Álvaro Figueredo dos Santos

Keyword(s):

Electrical Conductivity ◽

Moisture Content ◽

Saline Solution ◽

Potassium Acetate ◽

Physiological Changes ◽

Seed Moisture Content ◽

Moisture Contents ◽

Seed Moisture ◽

Germination Vigor ◽

Drying Conditions

The present work aimed to develop studies on the tolerance to dehydration of Blepharocalyx salicifolius and Casearia decandra seeds. In order to verify the effect of drying on the seeds, they were placed in desiccators containing a saline solution saturated with potassium acetate (23.5% RH) at temperature of 15 °C. After obtaining the desired moisture contents, the seeds were submitted to the germination, vigor, tetrazolium and electrical conductivity tests. It can be concluded that under slow drying conditions, the seeds of B. salicifolius and C. decandra were sensitive to moisture reduction of 29% to 25%, and lost viability at around 14% and 8% of moisture content, respectively. The physiological changes occurring during seed drying showed there was a decrease in viability and vigor and an increase in electrical conductivity values starting at 25% seed moisture content.

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Conservation of Garcinia imberti Bourd. through seeds

Plant Science Today ◽

10.14719/pst.2019.6.2.518 ◽

2019 ◽

Vol 6 (2) ◽

pp. 243-251

Author(s):

M Anto ◽

M Angala ◽

P S Jothish ◽

C Anilkumar

Keyword(s):

Seed Germination ◽

Relative Humidity ◽

Moisture Content ◽

Gibberellic Acid ◽

Biosphere Reserve ◽

Seed Storage ◽

Seed Moisture Content ◽

Evergreen Forests ◽

Seed Moisture ◽

Subsequent Exposure

Garcinia imberti seeds were collected during 2015-2017 from Shangili, Cheenikkala and Bonaccord evergreen forests of Agasthyamala Biosphere Reserve, the only abode of this endangered endemic species. Germinability of seeds were analysed through decoating, Gibberellic acid (GA3) and light inductive pre-treatments on fresh (62.8 % moisture content; MC) and desiccated (fast; 23.3% MC and slow; 30.5 % MC) seeds. The seed germination with impermeable coat (0.7-1.2 mm) was restricted which on decoating got enhanced. Application of GA3 along with exposure to light breaked dormancy within 4-6 days compared to non-treated seeds that took 238-254 days to germinate. Stored seeds behaviour revealed that seed moisture content and rate of germination were negatively correlated. Seed storage was found to be more efficient only up to 80 days at controlled seed banking conditions (20 ± 20C, 20 % relative humidity; RH). Both fast and slow desiccated seeds stored for 60 days in seed bank conditions exhibited 50.4 and 43.4 % of germination compared 39.4% germination of non-desiccated seeds. Hence fast desiccated and decoated G. imberti seeds pre-treated with GA3 on subsequent exposure to light alleviated dormancy. For seed banking, fast desiccated seeds with MC in between 40-20% are found to be promising.

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