Download
plant propagation asexual propagation n.
Skip this Video
Loading SlideShow in 5 Seconds..
Plant Propagation ASEXUAL PROPAGATION PowerPoint Presentation
Download Presentation
Plant Propagation ASEXUAL PROPAGATION

Plant Propagation ASEXUAL PROPAGATION

553 Views Download Presentation
Download Presentation

Plant Propagation ASEXUAL PROPAGATION

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Level 2 Horticulture Science Plant PropagationASEXUAL PROPAGATION US 20556 10 Credits – Internal Assessment

  2. Contents • Asexualvssexual Propagation • Asexual propagation (overview) • Division • Layering • Tissue culture • Cuttings • Budding and Grafting • Plant Breeders Rights

  3. Propagation:

  4. Asexualand Sexual Propagation • AsexualPropagation - using one parent plant to produce a new individual that is a clone (genetically identical) • Key words: offspring, new individuals, parent plant(s), • Sexual Propagation – recombination of the genes to produce a new individual that is a genetically different (also known as sexual reproduction) In Angiosperms -This always involves flowers and always results in seed. In Gymnosperms/ ferns and Moses this results in spores Question – if a plant self pollinates is it sexual or asexual propagation?

  5. Examples of Propagation Techniques

  6. Asexual Propagation (outline) We will be investigating 5 methods of asex prop. • Cuttings • Grafting and Budding • Division • Layering • Tissue Culture To begin to understand asexual propagation (AsexP) we need to understand meristematic cells

  7. Parts of a plant

  8. Importance of Meristematic cells • Meristematic cells – plant cells that are capable of dividing to create new plant cells that are unspecialised • Cambium layer – contains the meristematic cells • Unspeciallised cells are able to turn into any type of plant cells.... Eg • xylem • Phloem • Epidermal • Mesophyll

  9. Location of cambium layer

  10. Division • Plant structures

  11. Cuttings 4 types of cuttings • Leaf • Stem • Hardwood • Semi-hardwood • Softwood • Stem cuttings are the second most widely used form of propagation in horticulture. (Number one is seed)

  12. Semi- hardwood cuttings of Forsythia Leaf cuttings of petunias Hardwood cuttings of grape vines Tip (softwood) cuttings of Hydrangeas

  13. Importance of Meristematic cells • Meristematic cells – plant cells that are capable of dividing to create new plant cells that are unspecialised • Cambium layer – contains the meristematic cells • Unspeciallised cells are able to turn into any type of plant cells.... Eg • xylem • Phloem • Epidermal • Mesophyll

  14. Location of cambium layer

  15. How does crown tissue work. • The crown area of a plant contains both stem and root tissue and corresponding cells such as xylem, phloem and epidermis • Theses cells are already speciallised and will go onto create more of the same specialised cells. Crown of rhubarb plants

  16. Seed sowing To understand seed sowing technique we will be looking at: • Seed structure • Germination • Respiration • Seed requirements • Seed Dormancy Seed Sowing Menu

  17. Seed sowing – seed structure Three parts to a seed • Seed coat • Endosperm • Embryo ‘A seed is a plant in a box with it’s lunch’ Seed Sowing Menu

  18. Seed sowing – seed structure • Seed coat -the outer covering of a seed helps protect the embryo from injury and drying out. Seed coats can be thin and soft as in beans or thick and hard as in walnuts or coconut seeds. • Endosperm, a temporary food supply, is packed around the embryo in the form of special leaves called cotyledons or seed leaves. These are often the first parts visible when the seed germinates. • Embryo – the ‘baby’ plant. Seed Sowing Menu

  19. Two different situations: • Cotyledon(s) appear above ground as first leaves (seed leaves) • Cotyledon(s) remain below the ground

  20. Seed sowing – Seed Structure • There are two types of plants that produce seeds: Monocotyledons and Dicotyledons Seed Sowing Menu

  21. Seed Structure Seed Sowing Menu

  22. Germination • Starts when the seed begins to absorb water • Ends when the new plant is able to get all its’ energy from photosynthesis.

  23. Germination – the process • The seed absorbs water until it swells and smoothens its exterior wrinkles. • Swelling continues until the coat of the seed bursts open. • Food stored in cotyledons or endosperm soaks up water and soluble substances dissolve in it. • Respiration begins thus energy and raw materials are supplied by food for cell division and growth. • A radical appears first and then a pumule.

  24. Respiration • During respiration (in plants and animals) energy is released from sugar (glucose) by a series of chemical reactions. The sugar is broken down into carbon dioxide and water in a process which uses oxygen.

  25. Respiration in seeds • INPUTS OUTPUTS

  26. Seed requirements • List the inputs all seed require to germinate • Match your list to the following. • Allows seed to swell and break seed coat • Required for respiration • Speeds up the various chemical processes

  27. Seed dormancy • Dormant seeds are seeds that are still alive but when the seed is supplied all that it needs to germinate, - it doesn't. • The seed is asleep, waiting for the proper time to awaken. • Seed dormancy aids a species' survival by delaying germination so that 'overall germination' is dispersed over time.

  28. Seed Storage • Germination needs water. warmth and oxygen • Seed storage needs (the opposite) • Cool and dry! • Why can we not store seeds in a oxygen free environment?

  29. Seed Sowing Summary • Seeds don’t get re-assessment opportunities. Once they begin to germinate they either survive or die. • Seeds need the WOW factor to survive (water oxygen, warmth). Soil, light, CO2 are only for ‘grown-up’ seeds • A seed is a plant in a box with it’s lunch – but no dinner – if a seed is in the packet too long it will run out of lunch and die.

  30. End – Seed Sowing • Back to Main menu

  31. cuttings • Stem cuttings are the second most widely used form of propagation in horticulture. (Number one is seed)

  32. Semi- hardwood cuttings of Forsythia Leaf cuttings of petunias Hardwood cuttings of grape vines Tip (softwood) cuttings of Hydrangeas

  33. Division Examples of Asexual Examples of Sexual

  34. Grafting Examples of Asexual Examples of Sexual

  35. Layering • Both air layering and ground layering are used in commercial horticulture to produce cloned plants. • Layering is more difficult than taking cuttings but has the advantage that the plant is still attached to the parent plant receiving water and nutrients. Air layering is often used to fast track the creation of a bonsi The rooting process in layering may take form a few weeks to several years depending on the plant being propagated

  36. Air layering • Air Layering is generally used when other forms of propagation are difficult. • Two techniques are shown – but both expose the cambium layer • You tube – Creating a bonsi

  37. Ground layering • Ground layering is often used for brambles (cane berries such as raspberries etc.) • Also used for apples (although no longer commonly used) Compound trench layering Simple ground layering