Name: ___________________________________
Vegetative Propagation Reading Passage
Date: ________________
Vegetative
Propagation
Plants normally reproduce sexually. They have “male” and “female” parts and
produce male and female reproductive cells. Some plants have the ability to
reproduce asexually as well. Asexual reproduction in plants is called
vegetative propagation. There are six major modes of vegetative propagation
in plants. These are Runners, Bulbs, Tubers, Rhizomes, Cuttings and Grafting.
Some plants grow a stem from the side of the
plant. This is called a runner. The runner
grows horizontally across the ground. Buds
form along the runner. Each bud grows into a
new plant. The runner dies and dries out. The
plants along the runner survive on their own.
Strawberry plants reproduce this way.
Rhizomes are like underground runners.
Rhizomes are underground stems that grow
horizontally, away from the plant. New plants grow along the rhizome. Ginger
is an example of a rhizome.
Some plants grow swollen, underground stems called tubers. A tuber is not a
root; rather, it is a structure that grows buds that develop into new plants. An
example of a tuber is a potato. The “eyes” of a potato are buds.
Bulbs are underground stems specialized for food storage. The food is stored
in the thick leaves of the bulbs. Each bulb can develop into a new plant.
Onions are an example of a bulb.
A cutting is a form of artificial vegetative propagation. Scientists can artificially
reproduce a plant asexually. To do this, scientists take a cutting from a plant
and grow a new plant from the cutting. When placed in soil, the cutting will
grow new roots and leaves. The plant will be identical to the plant from which
the cutting came from.
Grafting is similar, yet different. Grafting consists of a cutting from one plant
called the scion is attached to the main body of a rooted plant, the stock. The
scion keeps its own identity. Seedless oranges and grapes are propagated by
grafting.
There are advantages and disadvantages to asexual reproduction in plants.
Vegetative propagation produces exact copies of the parent plant. This can be
advantageous because if the parent plant has desirable traits, the new plants
will have the desirable traits as well. Also, vegetative propagation usually
produces mature plants much quicker than by sexual reproduction. However,
vegetative propagation reduces variation. Less variation makes a species less
resistant to disease and more vulnerable to not being able to over changes in
the environment.
_______________________________________________________________
________
Name: ___________________________________ Date: ________________
Vegetative Propagation Answer Sheet
Questions
1. What is vegetative propagation?
2.
What are tubers?
3.
Compare and contrast runners and rhizomes.
4.
How are cuttings different from tubers, runners and rhizomes?
5. Which reproductive method is involved in the production of new
organisms by all of the species shown below?
a budding
b inbreeding
c artificial selection
d vegetative propagation
Answer: ____
6. Growing a crop of white potatoes by placing pieces of white potato
having buds (eyes) in the ground is a method of reproduction known
as
a
b
c
d
grafting
sporulation
binary fission
vegetative propagation
Answer: ____
7. The members of a certain species of grass in a lawn are genetically
identical. The best explanation for this observation is that the species
most probably reproduces
a
b
c
d
by an asexual method
after pollination by the wind
after pollination by a particular species of bee
by identical sperm fertilizing the eggs
Answer: _____
8. Which form of reproduction could produce five different kinds of
apples on one apple tree
a bulb formation B) fission
C) spore formation D) grafting
Answer: ____
Discussion:
Some advantages and disadvantages to vegetative propagation were
discussed in the reading. After considering these points, along with
other points you may consider on your own, do you think the
advantages of vegetative propagation outweigh the disadvantages?
Defend your answer.