Monocot (left) and dicot (right) seedlingsDevelopment of an angiosperm (maple) seedlingDevelopment of a gymnosperm (Douglas fir) seedling
Discover great deals on the many hard to find and one of a kind items available only on eBay!

Seedlings

A seedling is a young plant sporophyte developing out of a plant embryo from a seed. Seedling development starts with germination of the seed. more...

HomeHome
Bird & Wildlife AccessoriesBird & Wildlife Accessories
Garden DécorGarden Décor
Garden Structures & FencingGarden Structures & Fencing
Gardening & PlantsGardening & Plants
Children's Gardening ItemsChildren's Gardening Items
Fertilizer & Soil AmendmentsFertilizer & Soil Amendments
Garden Tools & EquipmentGarden Tools & Equipment
Hydroponics & Seed StartingHydroponics & Seed Starting
OtherOther
Pest & Weed ControlPest & Weed Control
Planters, Pots & Window...Planters, Pots & Window...
Plants, Seeds & BulbsPlants, Seeds & Bulbs
Aquatic PlantsAquatic Plants
PlantsPlants
Pond PlantPond Plant
SeedlingsSeedlings
SeedsSeeds
Water LilyWater Lily
BonsaiBonsai
Bonsai TreeBonsai Tree
Bonsai TreeBonsai Tree
Bonsai TreeBonsai Tree
Bonsai TreeBonsai Tree
Japanese BonsaiJapanese Bonsai
PlantsPlants
SeedlingsSeedlings
SeedsSeeds
BromeliadsBromeliads
Cactus & SucculentsCactus & Succulents
Cactus PlantCactus Plant
PlantsPlants
SeedlingsSeedlings
SeedsSeeds
FernsFerns
Flower Bulbs, Roots & CormsFlower Bulbs, Roots & Corms
Bearded IrisBearded Iris
Tall BeardedTall Bearded
Tall Bearded IrisTall Bearded Iris
Tall IrisTall Iris
Flower Plants & SeedlingsFlower Plants & Seedlings
AnnualsAnnuals
BiennialsBiennials
PerennialsPerennials
Flower SeedsFlower Seeds
25 Seeds25 Seeds
AnnualsAnnuals
BiennialsBiennials
Bulk SeedsBulk Seeds
Flower Seeds GiftFlower Seeds Gift
PerennialsPerennials
Groundcovers & VinesGroundcovers & Vines
PlantsPlants
SeedlingsSeedlings
SeedsSeeds
Vine SeedsVine Seeds
HerbsHerbs
Herb SeedsHerb Seeds
PlantsPlants
SeedlingsSeedlings
SeedsSeeds
HouseplantsHouseplants
African VioletAfrican Violet
OrchidsOrchids
Cattleya OrchidCattleya Orchid
Orchid PlantOrchid Plant
Ornamental GrassesOrnamental Grasses
Ornamental GrassOrnamental Grass
OtherOther
RosesRoses
Shrub Flower PlantShrub Flower Plant
ShrubsShrubs
PlantsPlants
SeedlingsSeedlings
SeedsSeeds
TreesTrees
EvergreenEvergreen
Fruit/FloweringFruit/Flowering
NutNut
OtherOther
ShadeShade
TropicalsTropicals
Orchid PlantOrchid Plant
Orchid PlantOrchid Plant
Orchid PlantOrchid Plant
Orchid PlantOrchid Plant
Orchid PlantOrchid Plant
Orchid PlantOrchid Plant
PlantsPlants
SeedlingsSeedlings
SeedsSeeds
Vegetables & FruitsVegetables & Fruits
4 Tomato Plants4 Tomato Plants
PlantsPlants
Seed SeedsSeed Seeds
SeedlingsSeedlings
Seeds & BulbsSeeds & Bulbs
Tomato SeedsTomato Seeds
Publications & SoftwarePublications & Software
Watering EquipmentWatering Equipment

A typical young seedling consists of three main parts: the radicle (embryonic root), the hypocotyl (embryonic shoot), and the cotyledons (seed leaves). The two classes of flowering plants are distinguished by their numbers of seed leaves: Monocotyledons (monocots) have one blade-shaped cotyledon, whereas dicotyledons (dicots) have two round cotyledons. Gymnosperms are more varied. For example, pine seedlings have up to eight cotyledons. The seedlings of some flowering plants have no cotyledons at all. These are said to be acotyledons.

Germination and early seedling development

During germination, the young plant emerges from its protective seed coat with its radicle first, followed by the cotyledons. The radicle orients towards gravity, while the hypocotyl orients away from gravity and elongates through cell expansion to push the cotyledons out of the ground.

Photomorphogenesis and skotomorphogenesis

Dicot seedlings grown in the light develop short hypocotyls and open cotyledons exposing the epicotyl. This is also referred to as photomorphogenesis. In contrast, seedlings grown in the dark develop long hypocotyls and their cotyledons remain closed around the epicotyl in an apical hook. This is referred to as skotomorphogenesis or etiolation. Etiolated seedlings are yellowish in color as chlorophyll synthesis and chloroplast development depend on light. They will open their cotyledons and turn green when treated with light.

In a natural situation, seedling development starts with skotomorphogenesis while the seedling is growing through the soil and attempting to reach the light as fast as possible. During this phase, the cotyledons are tightly closed and form the apical hook to protect the shoot apical meristem from damage while pushing through the soil. In many plants, the seed coat still covers the cotyledons for extra protection.

Upon breaking the surface and reaching the light, the seedling's developmental program is switched to photomorphogenesis. The cotyledons open upon contact with light (splitting the seed coat open, if still present) and become green, forming the first photosynthetic organs of the young plant. Until this stage, the seedling lives off the energy reserves stored in the seed. The opening of the cotyledons exposes the shoot apical meristem and the plumule consisting of the first true leaves of the young plant.

The seedlings sense light through the light receptors phytochrome (red and far-red light) and cryptochrome (blue light). Mutations in these photo receptors and their signal transduction components lead to seedling development that is at odds with light conditions, for example seedlings that show photomorphogenesis when grown in the dark.

Read more at Wikipedia.org


[List your site here Free!]

Lotus Flower Seeds Water lily Plants Bowl Indoor Aquatic 6 Colors Nelumbo DecorLotus Flower Seeds Water lily Plants Bowl Indoor Aquatic 6 Colors Nelumbo Decor $9.99 to Moni Lotus Seeds Flower Plants Water lily Bowl Indoor Aquatic Beautiful 6 ColorsMoni Lotus Seeds Flower Plants Water lily Bowl Indoor Aquatic Beautiful 6 Colors $5.99 to
Nymphaea alba European White Water Lily Flower Seeds Aquatic Plant Star ShapeNymphaea alba European White Water Lily Flower Seeds Aquatic Plant Star Shape $8.99 Sacred Lotus Nelumbo nucifera 10 Seeds (Free Shipping)Sacred Lotus Nelumbo nucifera 10 Seeds (Free Shipping) $12.99
10 Seeds Nymphaea nouchali stellata Blue Star Lotus Water Lily Water Plant10 Seeds Nymphaea nouchali stellata Blue Star Lotus Water Lily Water Plant $8.99 20 Lotus Seeds Aquatic Plants in the Home Courtyard Can Purify Water and Air20 Lotus Seeds Aquatic Plants in the Home Courtyard Can Purify Water and Air $2.09
$8.49 Crinum Lily, Erubescens, medium-size bulb - aquaticCrinum Lily, Erubescens, medium-size bulb - aquatic $25.00
5pcs White Lotus Seeds Snow White Aquatic plants Water Lilly nice fragrance5pcs White Lotus Seeds Snow White Aquatic plants Water Lilly nice fragrance $3.95 10 Seeds Nymphaea pubescens Hairy White Water Lily Flower - Seed Sale10 Seeds Nymphaea pubescens Hairy White Water Lily Flower - Seed Sale $6.99
Crinum Lily, Americanum, jumbo, blooming-size bulb - aquaticCrinum Lily, Americanum, jumbo, blooming-size bulb - aquatic $60.00 4500 Watercress Seeds Veggie Salad Herb 西洋菜 オランダガラシ 물냉이 xīyáng cài xà lách xoong4500 Watercress Seeds Veggie Salad Herb 西洋菜 オランダガラシ 물냉이 xīyáng cài xà lách xoong $9.58
Crinum Lily, Bayou Traveler, large blooming-size bulb - NewCrinum Lily, Bayou Traveler, large blooming-size bulb - New $25.00 Variegated Iris Pseudacorus Variegata Flag Perennial Bog Water Plant 3 SeedsVariegated Iris Pseudacorus Variegata Flag Perennial Bog Water Plant 3 Seeds $18.99
Nymphaea pubescens Hairy White Water Lily Flower Seeds Aquatic Pond or AquariumNymphaea pubescens Hairy White Water Lily Flower Seeds Aquatic Pond or Aquarium $8.99 Crinum Lily, Americanum, small-size bulb - aquaticCrinum Lily, Americanum, small-size bulb - aquatic $20.00
Wholesale Plant Seeds Thai Sun Pepper Cherry Lotus Flower Garden Bonsai PlantWholesale Plant Seeds Thai Sun Pepper Cherry Lotus Flower Garden Bonsai Plant $0.75 Crinum Lily, Erubescens, small-size bulb - aquaticCrinum Lily, Erubescens, small-size bulb - aquatic $15.00
600W Led Grow Lights Full Spectrum Lamp Indoor Hydro Plant Veg Bloom+Daisy Chain600W Led Grow Lights Full Spectrum Lamp Indoor Hydro Plant Veg Bloom+Daisy Chain $19.99 to 5 Seeds Lychee Lychy Litchi Seeds, Fruits E14.5, Tropical Fruit Lychee Seeds5 Seeds Lychee Lychy Litchi Seeds, Fruits E14.5, Tropical Fruit Lychee Seeds $5.99
Nymphaea nouchali stellata Blue Star Lotus Water Lily Seeds Aquatic PlantNymphaea nouchali stellata Blue Star Lotus Water Lily Seeds Aquatic Plant $8.99 Crinum Lily, Erubescens, large, blooming-size bulb - aquaticCrinum Lily, Erubescens, large, blooming-size bulb - aquatic $40.00
Crinum Lily, Oliganthum "West Indies Mini", large, blooming-size bulbCrinum Lily, Oliganthum "West Indies Mini", large, blooming-size bulb $20.00 10pcs Yellow Lotus Seeds Aquatic plants Water Lilly nice fragrance Out door Pond10pcs Yellow Lotus Seeds Aquatic plants Water Lilly nice fragrance Out door Pond $6.55
Seed Bowl Lotus 4 Color Mix Flower Water Aquatic Plants Nelumbo Home Rare 10 PcsSeed Bowl Lotus 4 Color Mix Flower Water Aquatic Plants Nelumbo Home Rare 10 Pcs $3.17 5pcs Blue Lotus Seeds Aquatic plants Water Lilly nice fragrance outdoor ponds5pcs Blue Lotus Seeds Aquatic plants Water Lilly nice fragrance outdoor ponds $3.95
20/37/46" Aquarium Led Light Multi-Color Full Spec Plant Marine 90 180 225 Leds20/37/46" Aquarium Led Light Multi-Color Full Spec Plant Marine 90 180 225 Leds $45.63 to Usa-100pcs flower daffodil seeds (not daffodil bulbs) aquatic plants NarcissusUsa-100pcs flower daffodil seeds (not daffodil bulbs) aquatic plants Narcissus $6.45
Crinum Lily, Caribaeum, large blooming-size bulb - NewCrinum Lily, Caribaeum, large blooming-size bulb - New $25.00 2500+ Seeds of Watercress Greens Aqua Seed Heirloom Organic Non-Gmo Xa Lach Xoon2500+ Seeds of Watercress Greens Aqua Seed Heirloom Organic Non-Gmo Xa Lach Xoon $2.99
Bali Red Lotus Rare Nelumbo Plant Seeds Aquatic plants Water Lilly - 05 SeedsBali Red Lotus Rare Nelumbo Plant Seeds Aquatic plants Water Lilly - 05 Seeds $3.95
Click to see more Seedlings items at www.ebay.com
Prices current as of last update, 09/21/20 6:44am.

Home Contact Resources Exchange Links eBay