Reimposition of conditional dormancy during air-dry storage of prechilled Sitka spruce seeds

AbstractPrechilling seeds of Sitka spruce (Picea sitchensis[Bong.] Carr.) at 4°C with 30% moisture content for 12–14 weeks (84–98 d) removed conditional dormancy (i.e. they were then able to germinate at 10°C). The non-dormant status was preserved after redrying to 6% moisture content. However, conditional dormancy was gradually reimposed during subsequent air-dry storage at 4°C and 6% seed moisture content in all five seed lots tested. Further investigations with one seed lot showed that reimposition was reversed by a second prechill treatment, but was reimposed again during subsequent air-dry storage. The trend of dormancy reimposition within seed lots over time was quantified by negative exponential relations between ability to germinate at 10°C and duration of air-dry storage. The progress of dormancy reimposition was influenced by seed storage moisture content and was most rapid at 4–10%. At higher moisture contents (15 and 20%) the rate of the reimposition of conditional dormancy was much reduced, while at moisture contents of 25 and 30% further loss in dormancy occurred. Thus it is clear that dormancy reimposition occurred during storage at low water potential rather than solely during desiccation from high to low water potential.

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Primed Lettuce Seeds Exhibit Increased Sensitivity to Moisture Content During Controlled Deterioration

HortScience ◽

10.21273/hortsci.42.6.1436 ◽

2007 ◽

Vol 42 (6) ◽

pp. 1436-1439 ◽

Cited By ~ 12

Author(s):

H.J. Hill ◽

Jesse D. Cunningham ◽

Kent J. Bradford ◽

A.G. Taylor

Keyword(s):

Moisture Content ◽

Elevated Temperatures ◽

Seed Viability ◽

Seed Storage ◽

Seed Priming ◽

Storage Conditions ◽

Seed Moisture Content ◽

Moisture Contents ◽

Lettuce Seeds ◽

Rate Of Decline

The Ellis-Roberts seed viability equation is used to predict seed survival after storage at specified temperatures and moisture contents. Seed priming, which can break dormancy and accelerate germination, can also reduce seed storage life. Because primed seeds were not used in developing the Ellis-Roberts equation, the reciprocal nature of specific seed moisture content (MC, fresh weight basis) and temperatures that applies to nonprimed lettuce (Lactuca sativa L.) seeds may not apply to primed seeds. To determine how priming affects lettuce seeds in relation to the viability equation, an experiment was conducted using two cultivars, ‘Big Ben’ and ‘Parris Island Cos’. Seeds primed in polyethylene glycol 8000 (–1.45 MPa, 24 h at 15 °C) and nonprimed seeds were first adjusted to 6% and 9% moisture contents and then stored at 48 and 38 °C for up to 30 days, respectively. These storage conditions (6% MC and 48 °C; 9% MC and 38 °C) were predicted by the viability equation to result in equal longevities. Subsequent viability assays at 20 °C revealed that nonprimed seeds in both storage environments exhibited similar losses in viability over time, thus validating the Ellis-Roberts equation and the use of these conditions to apply different but equal aging stress. Primed seeds of both cultivars deteriorated faster than nonprimed seeds as expected. However, primed seeds did exhibit different rates of deterioration between the storage environments. Primed seeds stored at 9% MC and 38 °C deteriorated faster than primed seeds stored at 6% MC and 48 °C. The rate of decline in probit viability percentage was three times greater in primed ‘Big Ben’ seeds stored at 9% MC and 38 °C than for those stored at 6% MC and 48 °C (–1.34 versus –0.26 probits per day, respectively). ‘Parris Island Cos’ seeds stored at 9% MC and 38 °C had twice the rate of deterioration that those stored at 6% MC and 48 °C (–1.19 and –0.49 probits per day, respectively). The results indicate that primed lettuce seeds were more sensitive to the adverse effects of higher seed MC than were nonprimed seeds during storage at elevated temperatures.

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Evaluation of Temperature and Moisture Content during Storage on the Germination of Flowering Annual Seed

HortScience ◽

10.21273/hortsci.30.5.1003 ◽

1995 ◽

Vol 30 (5) ◽

pp. 1003-1006 ◽

Cited By ~ 4

Author(s):

William J. Carpenter ◽

Eric R. Ostmark ◽

John A. Cornell

Keyword(s):

Relative Humidity ◽

Moisture Content ◽

Seed Storage ◽

Seed Moisture Content ◽

Moisture Contents ◽

Seed Moisture ◽

Storage Temperatures

Various combinations of temperature and moisture contents were used in evaluating the seed storage of nine genera of annual flowers. Relative humidity (RH) levels of 11%, 32%, 52%, and 75% provided wide ranges in seed moisture during storage at 5, 15, and 25C. At each temperature, total germination percentages (G) generally declined as seed moisture content increased during storage. The seed moisture range giving the highest G after 12 months of storage was determined for each temperature and plant genus. For all genera, seed moisture contents during storage increased as storage temperatures increased at constant RH levels. Moisture contents at 25C storage were 37%, 34%, 29%, and 20% higher than at 5C when RH levels were at 11%, 32%, 52%, and 75%, respectively.

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Leek (Allium porrum L.) seed development and germination

Seed Science Research ◽

10.1017/s0960258500001185 ◽

1992 ◽

Vol 2 (2) ◽

pp. 89-95 ◽

Cited By ~ 3

Author(s):

D. Gray ◽

J. R. A. Steckel ◽

L. J. Hands

Keyword(s):

Moisture Content ◽

Seed Development ◽

Developmental Stages ◽

Dry Weight ◽

Allium Porrum ◽

Seed Moisture Content ◽

Subsequent Performance ◽

Moisture Contents ◽

Seed Moisture ◽

Seed Growth

AbstractThe effects of development of leek seeds at 20/10°, 25/15° and 30/20°C (day/night) and drying of seed harvested at different developmental stages on subsequent performance were examined in each of 3 years. An increase in temperature from 20/10° to 30/20°C reduced mean seed weight from 2.90 to 2.55 mg as a result of a reduction in the duration of seed growth from 80 to 55 days; seed growth rate was unaffected. Seed moisture content reached a minimum, up to 35 days after the attainment of maximum seed dry weight and 115, 90 and 70 days after anthesis at 20/10°, 25/15° and 30/20°C, respectively. The curves relating seed moisture to time for each temperature regime were mapped onto a single line accounting for >90% of the variation in moisture content, using accumulated day-degrees >6°C instead of chronological time. Seeds were capable of germinating when seed moisture contents were >60% (fresh weight basis), but maximum viability and minimum mean time to germination were not attained until seed moisture contents at harvest had fallen to 20–30%. Germination was little affected by temperature of seed development. Drying immature seeds increased percentage germination. Growing seeds at 30/20°C and drying at 35°C and 30% RH raised the upper temperature limit of germination compared with growing at 20/10°C and drying at 15°C and 30% RH.

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Seed storage behaviour of 101 woody species from the tropical rainforest of southern China: a test of the seed-coat ratio–seed mass (SCR–SM) model for determination of desiccation sensitivity

Australian Journal of Botany ◽

10.1071/bt14037 ◽

2014 ◽

Vol 62 (4) ◽

pp. 305 ◽

Cited By ~ 6

Author(s):

Qin-ying Lan ◽

Ke Xia ◽

Xiao-feng Wang ◽

Jun-wei Liu ◽

Jin Zhao ◽

...

Keyword(s):

Moisture Content ◽

Seed Coat ◽

Tropical Rainforest ◽

Southern China ◽

Seed Mass ◽

Seed Storage ◽

Woody Species ◽

Seed Moisture Content ◽

Seed Desiccation ◽

Desiccation Sensitivity

The Xishuangbanna tropical rainforest in Yunnan Province is the greatest biodiversity hotspot in China. However, the biodiversity of this region is under threat, making seed conservation through seed and/or germplasm banking particularly urgent and crucial. Seed desiccation sensitivity limits the possibility of seed banking of 47% of tropical rainforest species. Thus, knowing if a species has desiccation-sensitive seeds is an important first step in seed banking; however, often resources are limited, making it difficult to determine storage behaviour for all the species in a region. Prediction of seed sensitivity using the SCR–SM model based on seed-coat ratio (SCR) and seed dry mass (SM) might be an alternative for determining desiccation sensitivity of seeds of each species. Here, seed-desiccation sensitivity of 101 woody species from the Xishuangbanna tropical forest were analysed using this model, and physiological determinations were made for a total of 25 species. Seed storage behaviour for 59 species was used for model validation, and storage behaviour of 88% of these species was successfully predicted. Seed storage behaviour of 83% of the 59 species was successfully predicted using the 1000-seed weigth–moisture content (TSW–MC) criteria, which include seeds with 1000-seed weight >500 g and seed moisture content at shedding of 30 –70%. The two predictive methods were subsequently used to predict seed desiccation sensitivity for another 42 species from Xishuangbanna whose storage behaviour was uncertain. Our results indicated that ~50% of the species in Xishuangbanna are likely to have desiccation-sensitive seeds.

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STORAGE OF TRUE POTATO SEED

HortScience ◽

10.21273/hortsci.27.6.577c ◽

1992 ◽

Vol 27 (6) ◽

pp. 577c-577

Author(s):

Noël Pallais

Keyword(s):

Moisture Content ◽

Seed Dormancy ◽

Potato Seed ◽

True Potato Seed ◽

Seedling Vigor ◽

High Moisture ◽

Seed Moisture Content ◽

Moisture Contents ◽

Seed Moisture

True potato seed of Atzimba × 104.12LB (intermediate dormancy) was dried to seed moisture contents ranging from 3.85 to 12.5% (dry wt basis) and was stored for 2 years at 30, 15 and 5°C. Seed was tested for various germination and seedling vigor criteria at 4 month intervals. Seed dormancy and viability were better preserved at seed moisture levels below 7% and as temperature decreased. High moisture (>9%) was lethal to seed stored at 30°C. TPS should be stored at <5% seed moisture content. Under this condition seed dormancy in the genotype studied was lost after about 12 months at 30°C.

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Moisture Contents in Bottle Gourd Seeds during Dry Heat Treatment and Subsequent Germination

HortScience ◽

10.21273/hortsci.39.4.758d ◽

2004 ◽

Vol 39 (4) ◽

pp. 758D-759

Author(s):

Seung-Hee Lee* ◽

Jin-Seok Kim ◽

Jung-Myung Lee

Keyword(s):

Heat Treatment ◽

Moisture Content ◽

Value Added ◽

Bottle Gourd ◽

Maximum Temperature ◽

Seed Moisture Content ◽

Dry Heat ◽

Moisture Contents ◽

Seed Moisture ◽

Dry Heat Treatment

Dry heat treatment (DHT), a powerful and agrochemical-free means of inactivating seed-borne virus and other pathogens, has been extensively used for value-added vegetable seeds in Korea, Japan, and some other countries. Since seeds are treated with extremely high heat (75 °C or higher) for a long time (72 h or longer), heat-induced phytotoxicity symptoms are frequently observed. Even though various internal and external factors, such as seed maturity and vigor, maximum temperature and duration of DHT, are known to influence the severity of phytotoxicity, precise control of seed moisture contents during DHT is regarded as one of the most important factors for successful DHT. In an ideal condition using a specifically designed DTH machine, seed moisture content of bottle gourd, initially around 6.20% to 0.64% when stored in a storage room with 50% RH, decreased by 1% after 24 h at 35 °C (5.20% to 0.23%), and further decreased below 4% after 24 h pretreatment at 50 °C (3.64% to 0.37%). The seed moisture content was further reduced down to about 2% after 72 h DHT at 75 °C (2.16% to 0.28%). During the post-treatment conditioning at 50 °C and 70% RH for 24 h, the moisture contents were raised to about 6%(5.94% to 0.45%), thus approaching the initial moisture content of 6% to 7%. During the germination period, treated seeds showed slower absorption of water as compared to the intact seeds, thus suggesting that this slow absorption of initial moisture absorption may be responsible for the slow initial germination frequently observed in treated seeds. Final germination and seedling vigor were not affected by DHT.

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Moisture adsorption isotherms and quality of seeds stored in conventional packaging materials and hermetic Super Bag

10.1101/463026 ◽

2018 ◽

Author(s):

Muhammad Amir Bakhtavar ◽

Irfan Afzal ◽

Shahzad Maqsood Ahmed Basra

Keyword(s):

Adsorption Isotherms ◽

Seed Quality ◽

Storage Period ◽

Seed Storage ◽

Packaging Materials ◽

Seed Moisture Content ◽

Moisture Adsorption ◽

Moisture Contents ◽

Seed Moisture

AbstractSeed moisture content (SMC) is an important attribute to seed quality. Maintaining seed dryness throughout supply chain (The Dry Chain) prevents seed germination and quality losses. Ambient relative humidity (RH) and temperature affect seed moisture and thereof seed moisture isotherm. Present study was conducted to compare the moisture adsorption isotherms of wheat, maize, cotton and quinoa seeds packed in hermetic Super Bag and traditional packaging materials including paper, polypropylene (PP), jute and cloth bags. Seeds were incubated at 60, 70, 80 and 90% static RH. Nearly straight line moisture isotherms for all crop seeds were obtained in Super Bag. Seed moisture contents increased in traditional packaging materials with increasing RH. At higher level of RH, moisture contents increased slightly (1-2%) in Super Bag, whereas this increase was much higher in traditional packaging materials (≈9% higher than original SMC at 90% RH). In second study, seeds were dried to 8 and 14% initial seed moisture contents using zeolite drying beads and were stored in hermetic and traditional bags for a period of 18 months. For all crop seeds, germination was severely affected in all packaging materials both at 8 and 14% initial SMC except storage in Super Bag at 8% SMC. Wheat seed stored in Super Bag at 8% SMC almost maintained initial germination while germination of cotton, maize and quinoa seeds declined 7%, 14% and 30% respectively in Super Bag at 8% SMC. Seed storage in Super Bag can help to prevent the significant increase in seed moisture at higher RH as is evident from moisture isotherm study, thus helps to preserve quality of maize, wheat, cotton and quinoa seeds by maintaining The Dry Chain throughout the storage period.

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Performance Evaluation of a Melon Shelling Machine with Different Power Sources

FUOYE Journal of Engineering and Technology ◽

10.46792/fuoyejet.v6i2.607 ◽

2021 ◽

Vol 6 (2) ◽

Author(s):

Temidayo C. Esenamunjor ◽

Ugwu H. Ubabuike

Keyword(s):

Performance Evaluation ◽

Moisture Content ◽

Throughput Capacity ◽

Seed Moisture Content ◽

Power Sources ◽

Moisture Contents ◽

Seed Damage ◽

Seed Moisture ◽

Machine Productivity ◽

Melon Seeds

Performance evaluation of an electric motor and a fuel-engine powered machine used for shelling melon seeds was performed in this study to determine the effects of shelling speed and moisture content on machine productivity. The melon seeds used for the evaluation of the existing melon shelling machine were sourced locally from Umungasi market in Aba, Abia state, Nigeria. The unshelled melon seeds as used were weighed (25g each), sprinkled with water and partially dried with natural air for 25 minutes. This enabled the skin coat became slightly softened and the cotyledon easily detached from the shell, thus making the shelling more efficient. To evaluate the parameters (machine productivity, throughput capacity and percentage seed damage), the melon seeds were employed. For the shelling performance, melon seeds of five different moisture contents (7.48, 10.24, 13.92, 18.36, 21.44%) dry basis (d.b.) at different shelling speeds (850, 1000 and 1200 rpm) were utilized in the evaluation. From the evaluation, results revealed that the machine has an optimal productivity of over 83% and percentage seed damage of 14.2% at seed moisture content of 21.44% and drum speed of 1200 rpm for both power sources. Maximum machine throughput capacity of over 940 kg/h was recorded at 1200 rpm and 21.44% moisture content for both power sources. Overall, results obtained indicated that the machine can effectively shell melon seeds and that seed moisture contents and shelling speed affected the machine productivity.Keywords— Performance operation, evaluation, motorized, melon, shelling machine

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Studies on the use of mutagenic agents in plant breeding. II. The effects of dose and seed moisture content on mutation production in Lupinus angustifolius by X-Rays

Australian Journal of Agricultural Research ◽

10.1071/ar9650301 ◽

1965 ◽

Vol 16 (3) ◽

pp. 301 ◽

Cited By ~ 3

Author(s):

JS Gladstones ◽

CM Francis

Keyword(s):

Moisture Content ◽

Mutation Rate ◽

Lupinus Angustifolius ◽

Mutation Rates ◽

X Rays ◽

High Moisture ◽

Seed Moisture Content ◽

Moisture Contents ◽

Seed Moisture ◽

Wet Weight

Seeds of Lupinus angustifolius were given X-ray doses of 2.5, 5, 10, and 20 kr at each of 12 moisture contents ranging from 6.1 to 18.1 % (wet weight basis). Various measures of injury were recorded in the X1 generation, and the types and rates of mutations in the X2. At moisture contents below 16%, total mutation rates were closely correlated with X1 injury. Injury and mutation rate decreased with increasing moisture up to 11–12% moisture, and thereafter remained at a constant minimum up to 16%. Between 16 and 18% moisture there was again an increase in X1 injury, but not in mutation rate. Between 6 and 12 % moisture, a linear relationship was found between moisture content and the logarithm of the dose required to cause a given level of injury or mutation. A possible mechanism for such a pattern of protection is discussed. Lethal mutations increased as a proportion of all mutations as dose and mutation rate increased. There were also proportionately more lethals at high moisture contents than in lower moisture treatments giving the same mutation rates. It is concluded that lethal and seedling chlorophyll-deficient mutations could be misleading when used as indicators of total and viable mutation rates, and that, contrary to the conclusions of some previous authors, no advantage is likely to be gained in practical breeding work from irradiating at high seed moisture contents.

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Seed survival in Chilean Nothofagus in response to desiccation and storage

Seed Science Research ◽

10.1079/ssr2005204 ◽

2005 ◽

Vol 15 (2) ◽

pp. 113-123 ◽

Cited By ~ 4

Author(s):

Pedro León-Lobos ◽

Richard H. Ellis

Keyword(s):

Moisture Content ◽

Seed Quality ◽

Seed Viability ◽

Seed Storage ◽

Forest Tree ◽

Ex Situ ◽

Hermetic Storage ◽

Moisture Contents ◽

Tree Seeds ◽

Initial Seed

Nothofagus alpina,N. obliqua,N. glauca,N. leonii,N. dombeyiandN. pumilioseeds exhibited consistent, albeit slight, sensitivity to extreme desiccation, but nevertheless maintained viability at low moisture contents and cool temperatures (–10° to –20°C) over 2 years.Nothofagus alpina,N. obliqua,N. glauca,N. leoniiandN. dombeyiconformed to the seed viability equation of Ellis and Roberts; sensitivity of longevity to temperature was quantitatively similar to that of crop seeds, sensitivity to moisture was somewhat less, and a low-moisture-content limit to the equation was detected at 4.8% moisture content in hermetic storage at 65 °C, and possibly similar moisture contents at 30–40°C. These five species show orthodox seed storage behaviour. Therefore,ex-situconservation of theseNothofagusspecies in seed banks is possible, but the quality of seed lots collected requires attention. Seed storage behaviour was not defined inN. pumilio: initial seed quality was poor and loss of viability was detected over 2 years at 0°, –10° and –20°C at 2.7% moisture content, but not at 5.2%. The results confirm that the economy of nature in seed storage physiology extends to forest tree seeds, but the repeated observation of reduced sensitivity of longevity to moisture in forest tree seeds requires further investigation.

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