The Effects of Drought on Arabidopsis Ecotypes Hunter Soltis, Victor Makali, Allison Poole, and Lucy Monigle

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The Effects of Drought on Arabidopsis Ecotypes
Hunter Soltis, Victor Makali, Allison Poole, and
Lucy Monigle Wofford College, South Carolina
Arabidopsis is found in almost every part of the
world. Arabidopsis ecotypes have adapted to
thrive in local environment, with varying
climates and precipitation. Does rainfall affect
the growth of three Arabidopsis ecotypes? The
ecotypes selected were determined by the amount
of precipitation they receive. These ecotypes
are Zloc-1 from Bulgaria, NZ1 from Hamilton, New
Zealand and Can-0, from the Canary Islands,
Spain. The Zloc-1 plant has adapted to a
temperate environment, with regular rainfall
equal to about 65 centimeters per year
(http//www.wordtravels.com). The NZ1 plant has
adapted to the high amounts of precipitation in
its region, with more than 121.9 cm per year
(www.climate-charts.com), while the Can-0 plant
had adapted to thrive in a region with low
precipitation, with average yearly rainfall
rarely exceeding 25.4 cm (www.brittanica.com). If
the plants from the different ecotypes are able
to survive under drought conditions, then the
durability and adaptability of the plant will be
shown.
Effect of Drought on Stem Growth of 3
Arabidopsis Ecotypes
The experiment produced results that were similar
between all groups, because of the conditions
that were applied to the three different
ecotypes. In the first week, the plants had
similar growth because there was no difference in
the soil, and the effects of the drought did not
have a large effect, which was biologically
unsurprising. The second week was more
biologically interesting, as the effects of both
the drought conditions and the ecotypes
demonstrate their adaptation to the environment
and drought tolerance. Our results supported the
null hypothesis. The Arabidopsis was not
negatively effected by drought conditions, but
instead thrived under excess watering. Our
results confirmed what is already known, that
Arabidopsis can survive under diverse conditions.
For future studies, we recommend that this
experiment be carried out for longer then two
weeks. Drought plants should have been planted in
a less water-saturated soil and watering
conditions need to be consistent. Measurements
for plants with irregular growth (bent or fallen)
could have been taken using a string method.
Simulated drought conditions will stunt stem
growth in Arabidopsis.
The graph shows that stem growth was not
negatively affected by drought conditions, but
displayed an adaptability to varied conditions.
Between the ecotypes, there was not much
variability in growth, which was unexpected.
18 seeds of ecotype Can-0 were placed in the soil
of each of two trays, tray C-1, and tray C-2.
This was repeated for ecotype NZ1 into tray N-1
and tray N-2, as well as for ecotype Zloc-1 into
tray Z-1 and tray Z-2. The seeds were germinated
for 2-4 days under a photoperiod of 16hrs
light/8hrs dark. Plants from N-1, Z-1, and C-1
were be the control group. They were watered
every other day. Plants from N-2, C-2, and Z-2
were be under drought conditions, and were not be
watered. All plants were kept under the same
photoperiod of 16hrs light/8hrs dark, with the
temperatures kept between 20 C and 25 C. Stem
lengths were measured once a week with a caliper
or measuring stick.
ANOVA Effect of Drought on Stem Growth of 3
Arabidopsis Ecotypes
www.wordtravels.com www.climate-charts.com
www.brittanica.com
During the first week, condition and ecotype had
little effect on stem growth. During the second
week however, condition and ecotype had
individual effects on the growth, and there was a
significant difference in growth when both
ecotype and condition are taken into account.
We would like to thank G.R. Davis, C.
Abercrombie, their assistants T. Player and A.
Steadman. Our class and the rest of the Biology
Department!