Threatened Native Trees in Guam: Short-term Seed Storage and Shade Conditions Influence Emergence and Growth of Seedlings

Seedling emergence and growth traits of three rare and threatened tree species in the Mariana Islands were studied within a range of incident light levels and up to 9 months of seed storage. Seedling emergence percentage and velocity were maximized in moderate shade for Elaeocarpus joga Merr., deep shade for Serianthes nelsonii Merr., and full sunlight for Tabernaemontana rotensis (Kaneh.) P.T. Li. Seedling height was increased by shade for E. joga and S. nelsonii. Height of T. rotensis seedlings was not influenced by incident light from 25% to 100%. Nine months of seed storage at ambient temperature did not influence emergence percentage of E. joga or S. nelsonii seeds. In contrast, seeds of T. rotensis began declining in seedling emergence percentage between 2 and 3 months of storage, and seedling emergence was nil by 4 months. This study represents the first experimental approach to determining the influences of light and storage on seed and seedling behavior for any rare and threatened taxa from the Mariana Islands. Our findings that revealed highly contrasting responses among the species provide a valuable start to building the knowledge base needed to respond to formal recovery or conservation plans by defining horticultural protocols for managing a conservation nursery.

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Seed Harvesting Time Affects Seedling Emergence, Vigour and Growth: Case Study of Rumex turcomanicus Czerep. (Polygonaceae)

Notulae Scientia Biologicae ◽

10.15835/nsb529042 ◽

2013 ◽

Vol 5 (2) ◽

pp. 244-248

Author(s):

Morteza ALIREZAIE NOGHONDAR ◽

Majid AZIZI

Keyword(s):

Growth Traits ◽

Seedling Emergence ◽

Seed Storage ◽

Dry Weight ◽

Seedling Vigour ◽

Root And Shoot Length ◽

Seed Harvesting ◽

Vigour Index ◽

Emergence Percentage ◽

Mature Seeds

Rumex turcomanicus Czerep., belonging to family Polygonaceae, is one of native green vegetable in Northeast Iran. Despite the high consumption, its seed germination and dormancy aspects is inconsiderable. In order to investigate the effects of seed harvesting date on seedling emergence, vigour and growth traits of R. turcomanicus Czerep., the seeds were harvested at five different times, i.e., two weeks after fruiting (WAF), 6WAF, 8WAF (mature seeds), 2 month after seed ripening (MASR) and 4MASR, and were sowed immediately, at agricultural college of Ferdowsi university of Mashhad, Iran in 2012-2013. The results was showed that the highest and lowest of seedling emergence percentage, seedling emergence rate, seedling vigour index, seedling fresh and dry weight, seedling root and shoot length, total seedling length and %final normal seedling (%FNS) was obtained in the seeds which were sowed 4MASR and 2WAF, respectively. Maximum and minimum of mean emergence time (MET) was observed in the seeds which were sowed 2WAF and 4MASR, respectively. Relationship between %FNS and MET and between %FNS and emergence percentage was highly significantly negative (-0.961) and positive (+0.962), respectively. Based on the results of this experiment, it seems that the problem of germination in most of the Rumex turcomanicus Czerep. seeds, is probably due to a kind of morphological dormancy, which is remained in most of the fresh seeds (collected 2WAF), and eliminated in the mature seeds (collected 2MASR). Also dry seed storage of the mature seeds for two months was improved seedling emergence and vigour, significantly.

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EMERGENCE AND SEEDLING GROWTH OF INBRED LINES OF CORN AT SUBOPTIMAL ROOT-ZONE TEMPERATURES

Canadian Journal of Plant Science ◽

10.4141/cjps87-059 ◽

1987 ◽

Vol 67 (2) ◽

pp. 409-415 ◽

Cited By ~ 8

Author(s):

A. MENKIR ◽

E. N. LARTER

Keyword(s):

Zea Mays ◽

Seedling Growth ◽

Root Zone ◽

Seedling Emergence ◽

Correlation Coefficients ◽

Dry Weight ◽

Inbred Lines ◽

Root Zone Temperature ◽

Emergence Percentage ◽

Zone Temperature

Based on the results of an earlier paper, 12 inbred lines of corn (Zea mays L.) were evaluated for emergence and seedling growth at three controlled root-zone temperatures (10, 14, and 18 °C). Low root-zone temperatures, 10 and 14 °C, were detrimental to emergence, seedling growth, and root growth of all inbred lines. Differential responses of inbred lines were observed within each temperature regime. The differences in seedling emergence among lines became smaller with increasing root-zone temperature, while the reverse was true for seedling dry weight. Simple correlation coefficients showed a significantly (P = 0.05) negative association between emergence percentage and emergence index (rate). Neither of these two emergence traits was significantly correlated with seedling dry weights. Seedling dry weights were significantly (P = 0.01) and positively associated with root dry weights. Two inbred lines exhibited good tolerance to low root-zone temperatures, viz. CO255 and RB214. A significant and positive correlation existed between emergence percentage at a root-zone temperature of 10 °C and field emergence in test with the same genotypes reported earlier. Selection at a root-zone temperature of 10 °C for a high percentage of seedling emergence, therefore, could be effective in identifying genotypes capable of germinating in cool soils. Furthermore, the significantly (P = 0.01) positive relationship between seedling dry weights at all root-zone temperatures and those from the field test suggest that strains with vigorous seedling growth in the field could be identified using low root-zone temperature regimes.Key words: Zea mays, root-zone temperature, cold tolerance

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Assessment of physiological potential of stored pea (Pisum sativum L.) seeds

Journal of Seed Science ◽

10.1590/s2317-15372013000100006 ◽

2013 ◽

Vol 35 (1) ◽

pp. 42-50 ◽

Cited By ~ 1

Author(s):

Fábio Mielezrski ◽

Julio Marcos-Filho

Keyword(s):

Electrical Conductivity ◽

Growth Habit ◽

Seedling Emergence ◽

Accelerated Aging ◽

Seed Storage ◽

Seed Vigor ◽

Seedling Length ◽

Pea Seeds ◽

Cold Chamber ◽

Pea Seed

Research on pea seed storage and the identification of efficient seed vigor tests for this species is still insufficient, especially for cultivars that produce wrinkled seeds used for consumption in natura. The objective of this study was to verify the accuracy of tests to assess the physiological potential of pea seed lots stored in different environments. Four seed lots of two cultivars, 'Telefone Alta' (indeterminate growth habit) and 'Itapuã' (determinate growth habit) were stored under different environmental conditions for 8 months: a) laboratory uncontrolled b) dry and cold chamber (10 ºC and 30% RH), c) controlled environment (20 ºC and 70% RH). Seed vigor (accelerated aging, electrical conductivity, seedling length and seedling emergence) was evaluated initially and after four and eight months storage. Results showed that the use of seed lots of high initial physiological potential is fundamental for guaranteeing the desired performance of pea seeds during storage. Wrinkled pea seeds should be stored between harvest and sowing in an environment in which the sum of the relative humidity (%) and temperature (°C) does not exceed 70. Physiological potential of pea seeds should be evaluated by at least two vigor tests; consideration to accelerated aging and electrical conductivity tests is recommended.

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Emergence rate of seedlings from hard okra seed coats and seedling growth of some genotypes of West African okra (Abelmoschus caillei)

Agricultural Science and Technology ◽

10.15547/ast.2019.02.019 ◽

2019 ◽

Vol 11 (2) ◽

pp. 118-122

Author(s):

P.M. Jonah ◽

G. K. Farauta ◽

Y. M. Kwaga ◽

H. E. Shehu ◽

N. M. Fakuta ◽

...

Keyword(s):

Seed Germination ◽

Seedling Growth ◽

Seedling Emergence ◽

West African ◽

Permeability Barrier ◽

State University ◽

Cropping Season ◽

Emergence Rate ◽

Emergence Percentage ◽

Seed Coats

Abstract. In 2017 and 2018 cropping season, field experiment was conducted at the Food and Agricultural Organization and Tree Crop Plantation, Department of Crop Science, Adamawa State University, Mubi using fifteen genotypes of West African okra. The study was undertaken to study the emergence rate of seedlings from hard okra seed coats, seedling growth and their development. The seeds of the genotypes were soaked in NaCl solution for 24 hours to accelerate the breaking of seed dormancy and to ease seed germination. Tough seed coat usually impairs seed germination by establishing a permeability barrier which can interrupt water uptake required for imbibition, radicle and seedling emergence. The combined analysis results revealed a highly significant (P≤0.01) difference among these genotypes with respect to days to first and 50% flowering including days to first harvest. Furthermore, accession 3 (NG/SA/DEC/07/0448) and accession 11 (Yar kwadon) flowered earlier, had shortest days to first harvest, recorded the highest number of seedlings and emergence percentage than the other genotypes studied.

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Initial Development of Soybean as a Bioindicator of the Potential of Leaching 2,4-D In Red Latosol

Applied Engineering in Agriculture ◽

10.13031/aea.12761 ◽

2018 ◽

Vol 34 (4) ◽

pp. 727-733

Author(s):

Vinícius Melo da Silva ◽

Tonny José Araújo Da Silva ◽

Maria Aparecida Peres de Oliveira ◽

Edna Maria Bonfim-Silva ◽

Jefferson Vieira José ◽

...

Keyword(s):

Seedling Emergence ◽

Residual Effect ◽

Control Treatment ◽

Depth Range ◽

Soil Columns ◽

Initial Development ◽

Leaching Potential ◽

Factorial Model ◽

Emergence Percentage ◽

Red Latosol

Abstract. The objective of this study was to evaluate the potential of leaching 2,4-D in Red Latosol using soybean as a bioindicator plant, to verify the residual effect of the distribution of the herbicide in the soil on the initial development of the plant. The experimental design is a 5 × 11 × 2 triple factorial model, with 5 treatments of water slides (20, 40, 60, 80 and 100 mm) applied by a rainfall simulator. The depth of 11 layers (0-5, 5 -10, 10-15, 15-20, 20-25, 25-30, 30-35, 35-40, 40-45, 45-50, and 50-55 cm) were mounted on soil columns using two groups (in the absence and the presence of the 2,4-D herbicide dimethylamine by application at a dose of 1500 g a.i. ha-1), with four replicates, making 440 experimental plots. The residual effect of the herbicide was evaluated by seedling emergence speed index, total seedling emergence percentage and plant height evaluation. The results demonstrated that the effect of 2,4-D herbicide distribution along the soil profile induces increases in the initial development of soybean when compared to the control treatment. However, the residual 2,4-D in the soil decreases with 80- and 100-mm sheets that have greater herbicide leaching potential beyond the depth range of the soil columns. Keywords: Residual effect, Seedling emergence, Glycine max.

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Effects of seed covering treatments on the emergence and seedling growth of crisp lettuce drilled with an experimental dibber drill

The Journal of Agricultural Science ◽

10.1017/s0021859600059426 ◽

1985 ◽

Vol 105 (3) ◽

pp. 535-541 ◽

Cited By ~ 5

Author(s):

D. C. E. Wurr ◽

Jane R. Fellows ◽

L. P. Bufton

Keyword(s):

Standard Deviation ◽

Seedling Growth ◽

Seedling Emergence ◽

Agricultural Engineering ◽

Percentage Time ◽

Moisture Regimes ◽

Dry Conditions ◽

Emergence Percentage

SUMMARYPelleted seed of the crisp lettuce variety Pennlake was sown on five occasions with units from either the experimental dibber drill designed by the National Institute of Agricultural Engineering or a Stanhay S870 drill. There were three dibber-drill treatments: seeds left in open holes or covered with peat–vermiculite or perlite. Seedling emergence and growth from each sowing of the four drill treatments were compared under different moisture regimes.There were large differences between drill treatments in emergence percentage, time to emergence of 50% of the seedlings which emerged (t50) and seedling weight at all sowings but there was a significant effect of drill treatment on the standard deviation of seedling emergence times at only one sowing. Of the dibber-drill treatments, only very occasionally did open holes or perlite cover give significantly better emergence than peat-vermiculite cover, which gave the most consistent results. In general, the dibber drill with peat-vermiculite cover gave significantly faster and higher emergence and heavier seedlings than the Stanhay drill. Differences in percentage seedling emergence tended to be greater under dry conditions.

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Effects of film-bottomed treatment on seedling emergence and growth of agana korshinskiiarid northwestern China

Plant Soil and Environment ◽

10.17221/206/2009-pse ◽

2010 ◽

Vol 56 (No. 4) ◽

pp. 186-193

Author(s):

X. Zhou ◽

Y. Yan ◽

Ch. Wan ◽

H. Wang ◽

L. Wu ◽

...

Keyword(s):

Soil Moisture ◽

Seedling Emergence ◽

Maximum Growth ◽

Northwestern China ◽

Promoting Effect ◽

Basal Diameter ◽

Shoot Height ◽

Caragana Korshinskii ◽

Arid Northwestern China ◽

Emergence Percentage

A field study was conducted to study the effectiveness of film-bottomed treatment (FBT) on the seed germination and seedling establishment of <I>Caragana korshinskii</I> Kom. in the arid Hexi Corridor of northwestern China in 2007 and 2008. The experiment involved three different depths of film-bottomed treatments (DFBT) (80, 90 and 100 cm) and a control with twelve replications in each treatment. Soil moisture, seedling emergence percentage, leaf characteristics, shoot height, main root length, basal diameter, biomass, biomass allocation, as well as root system distribution, were studied and were found to be significantly higher with FBT in respect to the check (CK) values. Soil moisture content increased with depths of film-bottomed treatments. Our study demonstrates that <I>C. korshinskii</I> can be grown successfully using FBT in arid areas and 90 cm DFBT gives the maximum growth-promoting effect.

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Dormancy and germination of the trimorphic achenes of a cold desert annual: spreading the risk over time

AoB Plants ◽

10.1093/aobpla/plaa056 ◽

2020 ◽

Vol 12 (6) ◽

Author(s):

Juanjuan Lu ◽

Wenjing Dong ◽

Dunyan Tan ◽

Carol C Baskin ◽

Jerry M Baskin

Keyword(s):

Seedling Emergence ◽

Dispersal Ability ◽

Dormancy Breaking ◽

Cold Desert ◽

Standard Procedures ◽

Emergence Percentage ◽

Desert Annual ◽

The Relationship ◽

Over Time ◽

Temporal Dispersal

Abstract Many studies have been done on the relationship between variation in morphology, dispersal ability and degree of dormancy of heterocarpic species with dimorphic diaspores. However, there are far fewer such studies on species that produce trimorphic diaspores. Our aim was to compare dormancy and germination of achenes from peripheral, intermediate and central positions in the capitulum of the diaspore-trimorphic cold desert annual Asteraceae species Heteracia szovitsii, an important component of plant communities in the cold deserts of NW China. Dormancy breaking/germination responses of the three achene morphs and of seeds isolated from the pericarp were tested in the laboratory using standard procedures, and seedling emergence phenology of the achene morphs was monitored under natural cold desert temperature conditions in an experimental garden with and without supplemental watering. Depth of dormancy of the three achene morphs was peripheral > intermediate > central. Seedlings from the three morphs emerged in spring and in autumn. Cumulative seedling emergence percentage from achenes during 47 months of burial was central > intermediate > peripheral. Central achene morphs emerged over a period of ~12 months after sowing, while intermediate and peripheral achene morphs did so for ~40 and 47 months, respectively. Thus, H. szovitsii exhibits a temporal dispersal strategy. No viable central or intermediate achene morphs were present after 16 and 40 months, respectively, but ~60 % of the non-emerged peripheral achenes morphs were viable after 47 months. Based on our results on diaspore dormancy and those of a previous study of diaspore spatial dispersal of H. szovitsii, we conclude that this species has a high–intermediate–low risk diaspore dispersal/dormancy strategy that likely increases the chances for population persistence over time and space.

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Response of Vegetable Seedling Emergence to Mustard (Sinapis alba ‘IdaGold’ and Brassica juncea ‘Pacific Gold’) Seed Meal

HortScience ◽

10.21273/hortsci11388-16 ◽

2017 ◽

Vol 52 (3) ◽

pp. 371-376 ◽

Cited By ~ 2

Author(s):

Xi Wang ◽

Genhua Niu ◽

Mengmeng Gu ◽

Paul A. Baumann ◽

Joseph Masabni

Keyword(s):

Brassica Juncea ◽

Seedling Emergence ◽

Sinapis Alba ◽

Suppressive Effect ◽

Control Treatment ◽

Mustard Seed ◽

Emergence Percentage ◽

Gold Seed ◽

Petri Dishes ◽

By Products

Mustard Seed Meals (MSMs) are by-products of biodiesel and an alternative to conventional herbicides for organic farming. However, MSMs might also suppress the emergence of vegetable seedlings. The objective of this study was to determine the response of vegetable seedling emergence to different MSM types and rates applied as an alternative herbicide. Six types of vegetable seeds, onion (Allium cepa), two cultivars of lettuce (Lactuca sativa ‘Black Seeded Simpson’ and ‘Buttercrunch’), mustard (Brassica juncea), kale (Brassica oleracea), and Mizuna (Brassica rapa var. japonica), were sowed in petri dishes containing germination mix. MSMs (Sinapis alba ‘IdaGold’ and B. juncea ‘Pacific Gold’) were incorporated into the germination mix at 0, 88, 176, or 265 g·m−2. Petri dishes were sealed for 1, 3, 5, or 7 days after sowing. For onion, ‘Pacific Gold’ had a greater suppressive effect on seedling emergence than ‘IdaGold’. For kale and mustard, ‘IdaGold’ and ‘Pacific Gold’ had similar suppressive effects on seedling emergence, but ‘Pacific Gold’ delayed emergence of kale at 88 g·m−2 when sealed for 3, 5, and 7 days. For Mizuna, ‘IdaGold’ had more suppressive effects than ‘Pacific Gold’ on seedling emergence, while sealing delayed but did not decrease emergence percentage (EP) at the lower rate (88 g·m−2) compared with the control treatment. For ‘Buttercrunch’ lettuce, there were no differences in the suppressive effects between the two MSMs. For ‘Black Seeded Simpson’ lettuce, ‘Pacific Gold’ had more suppressive effects on seedling emergence than ‘IdaGold’ when sealed at the lower rate (88 g·m−2) for longer durations (7 days) or at higher rates (176 and 265 g·m−2) for shorter durations (1 and 3 days). These results suggest that MSMs might suppress vegetable seedling emergence when applied at high rates (176 and 265 g·m−2), and sealing for more than 7 days after sowing may strengthen the suppressive effect. Extending sealing duration at the medium rates could achieve similar weed control results to high rates without sealing.

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Seedling emergence and early growth of Chinese fir under different light levels and seed positions: implications for natural regeneration

Canadian Journal of Forest Research ◽

10.1139/cjfr-2017-0412 ◽

2018 ◽

Vol 48 (9) ◽

pp. 1034-1041 ◽

Cited By ~ 1

Author(s):

Bo Liu ◽

Qingqing Liu ◽

Stefani Daryanto ◽

Xiangqing Ma ◽

Si Guo ◽

...

Keyword(s):

Natural Regeneration ◽

Southern China ◽

Seedling Emergence ◽

Soil Surface ◽

Light Level ◽

Early Growth ◽

Chinese Fir ◽

Light Levels ◽

Light Requirements ◽

Moisture Conditions

Chinese fir, Cunninghamia lanceolata (Lamb.) Hook. (Taxodiaceae), is an evergreen conifer primarily distributed in southern China. This species exhibits very poor natural regeneration, possibly due to low light and a thick litter layer. To improve the understanding of the natural regeneration capacity of Chinese fir, in this study, we conducted a shade house experiment to determine the optimum light requirements and seed positions for seedling emergence and early growth. The experiment involved five light levels (100%, 60%, 40%, 15%, 5% of full sunlight) and four seed positions (1 cm beneath the soil surface without litter, on the soil surface without soil–seed contact, on the soil surface and covered with litter, and 1 cm beneath the soil surface and covered with litter). Seedling emergence was highest at 5%–15% sunlight, whereas seedling height, root length, root mass, stem mass, leaf mass, and total mass were highest at 60% sunlight. For each light level, seed position significantly affected emergence and growth. The above-litter position inhibited seedling emergence and survival, while the below-litter position favored seedling emergence and early growth, particularly under high light levels. Based on these results, to enhance natural regeneration of Chinese fir, we recommend periodical thinning to increase light into the understory after successful seedling emergence. We also recommend sowing seeds deeper into the litter to improve soil contact and moisture conditions.

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