Download Increasing crop yield

GLASSHOUSES
Certain crops can be
grown in glasshouses
or in tunnels made from
transparent polythene.
This increases
their growth and
maximises the
yield,
for the following
reasons:
Transparent material allows natural
light in for photosynthesis during the
summer. Additional lighting gives a
‘longer day’ during the winter.
The ‘greenhouse
effect’ traps
longer wave radiation
and
the greenhouse heats
up.
Burning fuels increases the
temperature and carbon
dioxide levels, increasing the
rate of photosynthesis
It also adds water
vapour to the air
and the plant loses
less water through
its leaves.
Growing the plants
in a mineral solution
(hydroponic culture)
provides the right
balance of mineral
ions for the crop
being grown.
Growing crops in glasshouses
increases their yield!
Soil Minerals
Soil minerals are the source of the
elements the plants need to
manufacture the complex organic
molecules they need
Importance of nitrate ions
to plants
As nitrates
source of nitogen atoms for:




Amino acids and proteins
Nucleic acids
ATP
Component of chlorophyll molecule
Plants growing without
nitrates
typically stunted, yellow
Importance of magnesium
ions to plants
As Mg2+
source of magnesium atoms for:
 reaction centre for chlorophyll molecule
 essential cofactor for certain enzymes
Plants growing without
magnesium
Typical yellow leaves