The Impact of Elevated
Carbon Dioxide in Martian Atmosphere in the Process of Germination of Seeds
Global climate changes
tend to increase the concentration of CO2 in our atmosphere. The
structure and composition of atmosphere is entirely different in different
planets, not similar as that of earth.The cultivation of plant food in earth with drastic climate
changes or in other planets either in solar or non-solar systems under entirely
new atmospheric and soil conditions needs a detailed study to understand the
effect of increased CO2
levels in the process of germination and growth of planets. Besides the
abundance of CO2 in atmosphere, many other factors such as quality
of seeds, ambient temperature, soil pH, percentage of moisture ,concentration
of nitrogen and oxygen in the atmosphere also determine the successful
agricultural production .Infact all these factors play vital role in the
process of germination too.
An artificial Martian
atmosphere is created inside a large enclosure made of glass,whose open face is
kept immersed in a pool of water, so that the space enclosed is isolated from
the surrounding. The abundance of nitrogen is reduced by displacing the air
with fumes and smokes produced by burning camphor in the space before erecting
the enclosure. The abundance of oxygen in the space is reduced by burning a
candle inside. The concentration of carbon dioxide is increased by producing
the gas chemically. A beaker with baking powder and vinegar kept inside
liberates copious carbon dioxide gas. Taking calcium carbonate in a black
coated flat plate placed inside and heating with solar radiation also increases
carbon dioxide level inside regularly.. Calcium carbonate taken in a test tube
fitted tightly with a cork and an outlet tube is heated externally to conduct
carbon-dioxide into the enclosure through a long rubber tube whose outlet is
well immersed in the pool. The pressure inside is maintained at one atmospheric
pressure.The temperature inside is measured with two mercury thermometers.Due
to green house effect there is a temperature gradient of 0.6 o C /
cm height. The temperature at the lower layer is in the range of 28-35 o C
and it is 38-53o C at the upper layer depending upon the solar flux.
Two pair of cups with
different soil are taken and in each pair same number of fenu greek seeds (15)
are sowed for germination. One set of
pair is placed inside and other set is placed outside the enclosure to compare
the probability and the length of germination of the seeds After a couple of weeks ,as an average 10
out 15 seeds are sprouted in the cups
ouside while nothing is grown in the
cups inside. It showed that the germination of the spice is inhibited in
elevated carbon dioxide with reduced nitrogen and oxygen
The increased CO2
level increases the soil pH.If soil’s pH becomes too acetic (or too alkaline)
various key nutrients become insoluble
and unavailable to the plants and by this way it affects the growth of the
plants.Due to green house effect the temperature of the surrounding is
increased which alters the optimal soil temperature ,less favouring for maximum
number of seeds for germination.However the seed germination in response to
elevated CO2 has been reported to decrease 1-3,show no
change4 , to increase5 .It is shown that the responses vary among species6-7.
Germination is the growth
of seeds into seedlings – a kind of biological process converting the seed from
its passive to active phase.Biological materials are rich in carbon and occur
in aqueous environments and hence the presence of water play an important role
in determining the structure and specific activities of biopolymers. The
required biopolymers are always synthesized by the active plant itsef. But in
the case of passive seed, the biopolymers required for germination are initially
inducted by nature with congenial environment. During germination, the seed
synthesizes biopolymers with storage compounds in the seed, water in the soil
and oxygen and nitrogen in the atmosphere This primary biopolymers activate further a chain of biological process that determines
its further growth It decides all the
future of the plant- the development of
various part of the plant with specific activities,reproduction of
similar seeds for its existence etc ., The biopolymers are the root cause of
making the dormant seed to turn into self active seedling.Any change in the
environment thus affects this chain process of germination and growth.
In the atmosphere with
depleted oxygen, less nitrogen and elevated CO2 the process of
germination of fenugreek is very much hindered.Activating the seed to continue
its state of living requires the generation of specific biopolymers which can
be synthesized with water molecules
through hydrogen bonding .The presence of oxygen is necessary to provide energy
by oxidation required for the formation of biological molecules through hydrogen
bonding8. Thus the cultivation in Mars is possible only if an
optimum amount of oxygen is available in the environment to provide energy for
the formation of complex biopolymers through hydrogen bonding to awaken the
dormant seed. It is well established
that any damage in achieving the physiological maturity will have a substantial
reduction in germination.This is true in
the process of generation because of their deterorated ability to sysnthesize
biopolymers.
