Title
Key outcomes
Positioning teaching programme
Links to curriculum
Time allowance
Assessment
General references
D:\533576704.doc
Plant Growth and Development
Describe manipulations to influence growth and
development, and productivity, in plants
Winter terms
Science and technology curriculum documents
20 – 28 (5 – 7 weeks)
AS90454 (version 2)
7/03/2016
Specific Learning
Outcomes
/ Depth of coverage
Lesson
1
Assess student’s prior
knowledge of growth,
development, and productivity
and what affects them.
Students are able to define:
 Plant Growth - an
increase in size/dry
matter/mass.
 Development physiological changes
associated with growth
through to maturity.
 Productivity - : a
measure of the
efficiency of a
production system. It
includes but is not
limited to time of
production, quantity
and quality of the end
products, and the
economics of
production.
and describe the various
methods and measurements of
growth and productivity used in
NZ primary production
systems.
D:\533576704.doc
Learning Activities
Resources
Assessments
Brainstorm of what growth,
development and productivity are.
Record definitions.
Fresh vs Dry mass
Carry out the Fresh vs Dry mass
investigation. (Note: measurements
will need to be taken briefly at the
start of the lessons over the next two
weeks)
Homework.
Students can
construct a list of
the different ways
growth,
development and
productivity are
measured.
7/03/2016
Students can identify and explain how specific factors affect Growth, Development and Productivity in Plants
Factors needed to be covered are:
 Site selection
 Climate/Environment
 Cultivar
 Site establishment
 Nutrition and Water
 Pests and diseases
 Hormones
2–4
Students can:
Explain how the factors listed
above impact on growth,
development, and productivity.
Talk and Chalk: General
overview/discussion of how the
factors influence growth,
development, and productivity using
the PowerPoint presentation (Recap
on Year 11 work).
PowerPoint on factors
They need to be aware of both
effects on permanent crops such as
pip and stone fruit, grapes and more
seasonal crops such as lettuces.
Students can construct bubble or
spider diagrams for each factor that
links it to Plant Growth, Development
and Productivity.
D:\533576704.doc
7/03/2016
Techniques used to manipulate factors influencing the growth, development, and productivity
a) PLANT DENSITY
Plant density is a manipulation of the environment which may affect:
 light intensity
 air flow
 humidity
 pest and disease issues.
This can affect the growth and development in the following ways:
 Time to production
 Volume of production
 Quality of product

5–7
Students will need to be able
to:
 Explain how Plant Density
affects the factors which
influence growth,
development, and
productivity.
 Justify the use of one
technique that
manipulates plant
density over the
alternatives.
D:\533576704.doc
Discuss with students what plant
density is and what it will affect.
Kiwifruit Data Exercise on Density
Students are to describe and explain
how each factor is affected.
Hand out and complete the Kiwifruit
Data Exercise.
Density of plants investigation
Set up the Density of plants
investigation.
7/03/2016
The effect on Plant Growth,
Development and Productivity can be
illustrated using a range of examples.
Time to Production
e.g. etiolated greenhouse tomatoes
take longer to start flowering than
healthy plants.
Volume of Production
e.g. pip fruit production in the first ten
years is strongly correlated to trees
per hectare (fewer trees less
production, more trees more
production). In the past apple trees
were planted at 450 trees/ha; recent
plantings with dwarf rootstocks are
planted up to 3000 trees/ha this
allows more fruit to be harvested
earlier.
Quality
e.g. the density of squash plants
influences the size of the individual
product. The optimum harvest size for
squash is 900grams which is required
for the Japanese market.
e.g. kiwifruit size is influenced by
canopy density more than crop load.
With a denser canopy there is a
reduction in both crop yield and size
of the fruit.
e.g. lettuces can by attacked by
aphids when they are planted too
close together
D:\533576704.doc
7/03/2016
b) FERTILISER and WATER APPLICATION(timing, rate, method, etc)
The growth and development of plants is related to:

Water

Fertilisers

CO2 /O2
8 - 13
Students will need to be able
to:
 Explain how fertiliser and
water application influence
growth, development, and
productivity.

Justify the use of one
technique that manipulates
water or nutrient
availability over the
alternatives.
Review Environmental factors and
Plant Processes (Worksheet used in
2.2)
Students need to understand how
Plant Growth is affected by the
availability (or lack of) the three
factors listed.
Handout the handout ‘Effect of light
and water on plant production ‘
Carry out the Light Intensity Expt
The Plant Nutrients and cellular
activity workskeet can be used as a
resource or given as a homework
tasksheet (Great diagrams to colour in
and paste into notes).
Environmental Factors and Plant
Processes
Fertilisers and plant nutrition.ppt
Effect of light and water on plant
production handout
Who dunit? Light intensity experiment
Interpreting experimental data exercise
CO2 enrichment link
Plant nutrients and cellular activity
The role of water in Photosynthesis
and plant growth needs to be fully
discussed and understood by the
students.
The worksheets ‘Water availability
and Irrigation’ and ‘the role of water in
plants’ both come from the 2.2 unit.
D:\533576704.doc
7/03/2016
The graphs in the first resource give
examples of effects on
growth/productivity and could be used
as practice for answering ‘justification’
questions.
Some key points to consider:
The effect of water on Plant Growth,
development and productivity
Water availability and irrigation
The role of water in plants
Water
Water availability is the most critical
factor in plant productivity.
i.e. the rate of photosynthesis
decreases rapidly after 30% of the
water content of the leaves is lost and
ceases altogether at approximately
60% loss.
Fertilisers
The changes to a fertiliser regime
often depend on the time of year and
development of the plant.
e.g. tomatoes - high nitrogen early in
the vegetative phase and increased
potassium and phosphorus when
flowering and fruiting.
e.g. maize has a general purpose
fertiliser applied at planting and an
application of urea as a side dressing
at the forth to sixth leaf stage to boost
leaf growth prior to flowering.
D:\533576704.doc
7/03/2016
c) TIME OF SOWING AND HARVESTING
This is important from 3 perspectives –
1. Climate
2. Fresh Produce – maturity must coincide with consumer demand
3. Processed Crops – maturity must dovetail to factory schedule
14 - 16
Students will need to be able
to:


Explain how the time
of sowing/ harvesting
affect the factors
which influence
growth, development,
and productivity.
Justify the use of one
manipulation of time
of sowing/ harvesting
over the alternatives.
over others.
Classroom discussion on how our
climate varies throughout the year and
how growers need to time the sowing
of many seasonal crops. (Review
work from 2.2 on GDD’s)
Local newspapers
Produce Manager of Supermarket
“Grower Magazine “
http://www.vegfed.co.nz/about/1_whatis.
cfm
Be able to describe the impact of
sowing date on maturity date and
consequences of failure to meet
deadlines. Students list some of the
potential consequences.
The link between consumer demand
for the product and the price paid
needs to be emphasised. A good
example of this is the production of
roses for Valentines Day.
Research seasonal crops linking price
and availability using produce market
reports in newspapers.
eg stone-fruit prices - effect of S.
Island production on N.Island prices;
eg. Summer vegetables (tomatoes,
lettuce, aubergine, capsicums)- effect
of imported Australian tomatoes on
NZ winter tomato price
Extension:
Discussion with local grower or factory
field officer.
D:\533576704.doc
7/03/2016
d) SELECTION AND USE OF HORMONES
17 - 18
Students need to be able to:


Explain hormone
selection and use
affects the factors
which influence plant
growth, development,
and productivity.
Justify the use of one
technique that
manipulates plant
hormones over the
alternatives.
Plant hormones Fact sheet
While a brief overview of natural plant
hormones/responses is required, it is
the use of hormones in specialist
situations/contexts that should be the
focus here and the ways that
hormones can be used/ manipulated
by growers to produce a beneficial
outcome in terms of plant
growth/development or productivity.
Eg Hormone herbicides, Rooting
Hormone powders/gels, Fruit setting
hormones (eg Tomset)
Plant hormones and tropisms
worksheet
Ripening of bananas with apples
Hand out, read and complete the two
attached worksheets.
Carry out the Banana ripening
worksheet.
Use this as a context for a
‘justification’ task – ie justify the use of
a plant hormone for a particular
purpose over alternative options.
D:\533576704.doc
7/03/2016
f) TRAINING
19 - 20
Students need to be able to:


Explain how training
affects the factors which
influence plant growth,
development, and
productivity.
Justify the use of one
training technique over
the alternatives
Recap on Year 11 work on what
‘Training’ is, why it is done and
common techniques.
Determine the most appropriate form
of training for the desired product
*Single leader trees for pip and stone
fruit – comparison between
vase and single leader – tabulate.
PowerPoint on pruning and training
Introduction to pruning
*Vines(grapes/kiwifruit) – need to
leave one year wood for next
season’s
crop
*Above ground grow bags-cherries
*Ornamentals – topiary / standard
plants
If possible visit an Orchard or
vineyard/glasshouse and observe
different training techniques.
D:\533576704.doc
7/03/2016
g) CONTROLLED ENVIRONMENTS
The growth, development and productivity of plants is related to:
 Climate
 Controlled environments
21- 24
Students need to be able to:

Explain how the climate/
environment effects the
factors which influence
plant growth,
development, and
productivity.
 Justify the use of one
technique that
manipulates the climate/
environment over the
alternatives.
Climate
(the effect of climate on plants is
taught in detail in 90451 and an
overview is all that is required here)
The effect of rainfall, sunlight, frost,
wind, humidity all greatly
impact on plants.
(A reminder to link the relevant
factors back to training techniques
and the effect on micro-climates)
Controlled environments
Students will need to explain how
these manipulations effects the
factors which influence growth,
development, and productivity and
justify the use of one technique over
others.
Photograph of a plastic house at night
Explain how (and why it necessary
that) the environment can be
controlled by growing a crop
undercover.
D:\533576704.doc
7/03/2016
h) PESTS AND DISEASES
The growth, development and productivity of plants is related to:
 Pests and diseases
 pest and disease control
25- 27
Students will need to be able
to:
 Explain how pests
and diseases affect
the factors which
influence growth,
development, and
productivity.

Justify the use of one
technique that
manipulates/ controls
pests and diseases
over the alternatives.
Review the common groups of pests
and diseases from Year 11 and how
they impact plant growth,
development and productivity. The
downgrading/rejecting of fruit with any
signs of pests/ diseases and their
unsuitability for exporting/ sale can be
emphasised.
http://plantclinic.cornell.edu/FactSheets/
botrytis/botrytis_blight.htm
Explain how pests and diseases
influence growth and development of
commercial crops.
Identify the conditions under which
pests and diseases flourish.
Be able justify a chosen method of
control over alternative methods of
pest and disease control
EXTENSION
Research the life cycles of a variety of
common pests and disease
eg Mildew, botrytis, whitefly, thrips,
aphids and Tomato Mosaic Virus
http://www.hortnet.co.nz/key/
Use the key to common pests of
stonefruit/ pipfruit on the ‘hortnet’
website.( Lots of pictures here!!)
D:\533576704.doc
7/03/2016
END OF UNIT TEST
Formative
Assessment
90454-exam 2004
28
90454-exam 2003
D:\533576704.doc
7/03/2016