1. Rate of Transpiration Centarurea Cyanus
Nicole Colón, Carmary Soto, Elvin Morales
Abstract:Transpiration is one of the most common processes of temperature regulation. The
rate of transpiration depends on several weather factors, such as wind and humidity, as well as
structural factors. Previous studies have shown that increase of air movement result in increase
of transpiration by the plant. This study aims to prove if wind affects the transpiration of
Centaurea cyanus plant by increasing the rate of transpiration. Using a potometer, the range of
transpiration was measured every three minutes for a total of thirty minutes, resulting in an
increased transpiration rate for the plant that had an air current applied to it. In conclusion, wind
is indeed a contributing factor in the determination of transpiration rates, effectively increasing
them in the sample plants.
Introduction: cornflower make the herb especially
effective against inflammation in the region
Centaurea cyanus, more commonly of the eyes and conjunctivitis. The seed have
known as “Bachelor’s button” or also been used as gentle laxatives for
“Cornflower”, is annual flowering plant children and as a stimulant for enhancing
belonging to the Asteraceae family. digestion and to support some internal
Because C.cyanus can be easily cultivated in organs such as the liver.
a wide variety of soils (preferably in well-
drained soils) and can tolerate extremely Plant transpiration is the release of
exposure to sun light this herb can be easily water vapor to the atmosphere through the
grown in areas such as North America, stomata by the evaporation of water located
Europe, Brazil, and Asia. Its leaves are long in the intracellular spaces inside the plant.
and they emerge alternately on the stem, Approximately 10% of all moist found in
which can grow up to a height of 16-35 the atmosphere is released by transpiration;
inches and is usually very thin and ramified, however, many external factors contribute to
with flowers (usually containing a wide the rate of transpiration in organisms.
range of colors such as blue, pink or white) Several factors, such as temperature,
growing at their tips. The flowers are humidity, soil moisture, and air movement
hermaphrodites, meaning they have male contribute to how much water vapor is
and female organs, and are pollinated with released from the organism. Humidity and
the help of other organisms such as insects. air movement have a close relationship in
terms of affecting the rate of transpiration in
C. cyanus has a wide range of plants; as water inside the cell evaporates, it
medical applications. In French herbal saturates the air surrounding the leaf with
medicine it is used for the eye treatments in water vapor, increasing the humidity around
the form of poultices or eyewashes; the the leaf, which in turn decreases the rate of
gentle antiseptic and astringent properties of

2. transpiration. However, if wind is present, transpiration in the plant will rise. In this
blowing away the humid air and replacing it experiment the rate of transpiration of C.
with drier air, water evaporation inside the cyanus, a common grassland plant, when a
plant will continue, and therefore, the rate of air current is applied.
syringe to refill the pipettes if necessary; and
a fan to produce the air current. First the
Materials and Methods stem was cut with a razor blade in order to
The experiment was based upon fit the plant in the connector tube. Then,
seeing how the rate of transpiration of C. with a syringe, the pipette was filled with
cyanus was affected when an air current is water until the meniscus read 0.9mL
applied. A potometer, or transpirometer approximately. The plant stems were then
shown in fig. 1, was utilized, which is a placed in the connector tubes and only one
device used for measuring the rate of water had a fan placed directly in front of it; the
uptake of a leafy shoot. . The set-up other served as a control group. Every three
consisted of a 1.0 mL pipette with water; a minutes, for a period of thirty minutes, the
connector tube to transport the water; amount of water in the 1mL pipette was
clamps to hold the pipette and the plant in measured to see the rate of water uptake of
place; two lamps to induce photosynthesis; a each stem cutting, which is directly
proportional to their rate of transpiration.
Results
At first large difference between the two
plants were not shown, but after several
minutes the plant with the fan placed in front
of it exceled in showing more transpiration
than the control. According to the
observations made during the experiment
Plant B, containing the variable (wind), as
shown in figure 1, show a wide range of
transpiration while the control shows not
transpiration at all. From the minute 6, table
1, the plant with the fan placed in front of it
excelled in showing more transpiration than
the control. The amount of water absorbed,
and therefore, the rate of absorption of
Centaurea cyanus plant increased by a
Fig.1: Potometer set-up
factor of approximately 68 when exposed to
wind.

3. Time (minutes) Control (without breeze) Experimental (with breeze)
0 0.8975 0.8460
3 0.8950 0.8445
6 0.8973 0.8440
9 0.8970 0.7985
12 0.8970 0.7875
15 0.8970 0.7968
18 0.8968 0.7960
21 0.8965 0.7948
24 0.8965 0.7935
27 0.8965 0.7925
30 0.8960 0.7440
Table 1: Average values of absorbed water
Figure 1: Average values of absorbed water
Average values of absobed water
0.95
Pipet measuments (mL)
0.9
0.85
0.8
0.75
0.7
0 3 6 9 12 15 18 21 24 27 30
Time (minutes)
Control (without breeze) Experimental (with breeze)
*Pipet measurements are inversely proportional to the amount of water transpired.

4. Discussion
The data in the Table 1 demonstrated present, the water vapor near the surface of
that during the first few minutes a large the leaf is blown away, affecting the vapor
difference between the two plants wasn’t pressure difference across the surface and
evident, but after six minutes the accelerating the rate of evaporation of water
experimental plant absorbed more quantities from the intercellular spaces in the leaf,
of water that the control plant. This is due to which in turn, increases the rate of
the fact that wind carries away the humid air transpiration (Raven et al., 2005). The
over the plant’s surface, more specifically, results also coincide with recent
the leaves. This, in turn increases the rate of investigations that state that increase air
water evaporation from the intercellular circulation increase the rate of transpiration
spaces inside the leaf, which increases the (Thongba et al., 2010). In conclusion, the
rate of transpiration. This is evident by the hypothesis of this investigation was proven
amount of water that the experimental plant to be true because the environmental factor,
absorbed; the plant was losing water through wind, did in fact increase the rate of
evaporation. These results are consistent transpiration of the Centaurea cyanus plant.
with the information presented in the class Further investigations might be able to
textbook that states that this phenomenon is provide an insight into more adequate
due to the fact that when there is wind techniques for plant care.