Seedgermination process ppt
6 likes11,331 views
Seed germination is initiated by water absorption and warmth, breaking dormancy through mechanisms like seed coats, inhibitors, scarification, light, or stratification. Dormancy is caused by thick seed coats, inhibitors like abscisic acid or phenolics, and insufficient development, and can be overcome by scarification, repeated rain, stratification, or fungus association in some seeds like lettuce or orchids.
Seedgermination process ppt
- 1. Seed Germination:Emergence of Radicle through Seed Coat Water Warm Temperature So if you want to store seeds what are the conditions? Dry Cold Dormant seeds need more than moisture and warmth: Thick Seed Coat Thin Seed Coat Insufficient Development Inhibitor: Abscisic Acid Inhibitor: Phenolics Scarification Light Soil Fungus Association Stratification > Vernalization Leaching by Repeated Rain Kentucky Coffee Tree Lettuce Orchids Most CT feral plants Cacti Darkor or Pea Dormancy is caused by: Is overcome by: Example: Seeds lacking dormancy need: nick digest scrub fire freeze-thaw cycles 6 weeks at 4° C 20° C
- 2. Barley Seed Germination Fruit+Seed Coat Endosperm Aleurone Layer Storage Protein Amino Acids hydrolysis translation transcription hydrolysis starch sugar α-amylase RNA DNA GA imbibition water radicle apex shoot apex growthcotyledon monocot maltose Embryo exocytosis
- 3. Capsella Seed: Seed Coat Endosperm Embryo Shoot Apex Cotyledons - dicot Hypocotyl Radicle Root Apex Micropyle
- 4. Lettuce Seed Germination 660 nm 730 nm dark Seed Coat translation transcription hydrolysis starch sugar α-amylase RNA DNA imbibition water radicle apex shoot apex growthdicot photoreversibility Pfr Pr photoactivation Embryo phytochrome red and white light stimulate germination cotyledons