22.1 Natural Cloning in Plants Flashcards
Definition of cloning
A way of producing offspring by asexual reproduction, clones are genetically identify to both parent organism and each other
Definition of vegetative propagation
The artificial production of natural clones for use in horticulture and agriculture
What does natural plant cloning occur in?
Bulbs, runners, rhizomes, stem tubers
How does natural cloning occur in bulbs and an example?
eg. daffodils
Leaf bases swell with stored food from photosynthesis, buds form internally which develop into new shoots and new plants in the next growing season
How does natural cloning occur in runners and an example?
eg. strawberries, spider plants
A lateral stem grows away from the parent plant and roots develop where the runner touches the ground, a new plant develops, the runner eventually withers away leaving the new individual independent
What is another word for natural cloning?
Vegetative propagation
How does natural cloning occur in rhizomes and an example?
eg. marram grass
A rhizome is a specialised horizontal stem running underground, often swollen with stored food. Buds develop and form new vertical shoots which become independant plants
How does natural cloning occur in stem tubers and an example?
eg. potato
The tip of an underground stem becomes swollen with stored food to form a tuber or storage organ. Buds on the storage organ develop to produce new shoots (eg. the ‘eyes’ of a potato)
How are natural clones used in horticulture?
Creating clones through cutting, increase plant number cheaply by spilling up bulbs, removing young plants from runners, cutting up rhizomes
What are the advantages of vegetative propagation (natural cloning) in agriculture?
-Some crop plants cannot reproduce sexually
-Young seedlings are less likely to survive
-Quicker than growing from seed/sexual reproduction
-Uniform/predictable, shape/size/quantity/yield
-Easier to harvest
-Can be done at any season/time of the year
What are the disadvantages of vegetative propagation (natural cloning) in agriculture?
-No genetic variety
-Does not allow for natural selection
-Unable to adapt to environmental conditions
How do you produce a clone from a cutting?
-Cut a section of shoot from a healthy plant
-Cut stem at a slant
-Cut between the nodes
-Dip in rooting powder/plant hormones, specifically auxin
-Place it in soil and add water
-To reduce transpiration, cover with a plastic bag, remove some leaves
How do you reduce transpiration of a cutting?
Cover with a plastic bag, remove some leaves
