Saddleback Journal of Biology - Saddleback College

Fall 2009 Biology 3B Paper
Figure 1. Mean height of RCBr grown in conventional
soil (8.574 0.345 cm ( S.E.M, n=35) and organic
soil (7.87 0.317 cm (n=39) (p= 0.067662).
Figure 2. Mean cotyledon width of RCBr grown in
conventional soil (1.72 0.0371 cm and organic soil
(1.11 0.0270 cm (p= 3.2x 10 -20 ).
Discussion
The data and results show that there is a
difference in all categories tested between the two
groups with, organic soil germinating in 100% of seeds
planted(39 germinators out of 39 sown), while
conventional only 97.2% (35 germinators out of 36
sown). In addition to this the conventional soil also
yielded plants with greater averages in all of the other
three measured categories. In regards to germination
and height values there was no significant, statistical
difference between the two groups, therefore, in the
two categories with statistical differences, conventional
soil proves to be the better growth medium. The RCBr
grown in conventional soil had cotyledons which
radically outgrew those grown in organic soil, and the
number of flowers in the conventional soil group also
outnumbered those in the organic soil group. Therefore
the results of this particular experiment indicate that
the hypothesis being tested was incorrect. The
conventional soil is specifically engineered for the
purpose of optimal plant growth, as an alternative to
organic soil. Even in RCBr, which requires low
nutrient levels and is easily sustainable, the
conventional soil allowed for better growth. Other than
the growth medium, all variables in this experiment
were kept constant except for one; the pH content of
each soil. Although RCBr is assumed to grow better in
a more basic environment (Carolina Lab Supply,
2009), the greater pH of the organic soil did not affect
the hypothesis. There is some possible error on the part
of the researchers however as the conventional soil
used in the experiment had fertilizers added while the
organic soil had none. This variance in the growth
medium may have had a large impact on the results of
this study. It is for this reason that further research is
encouraged in order to confirm these results. In
addition if this experiment were to be expanded on, soil
pH should be measured beforehand and altered to be
made constant and the null hypothesis assumed.
Literature Cited
Butrum, R. R., Chang, F. H., & Leung, W.-T. W.
(1972). Food Composition Table For Use in East Asia.
Retrieved
October 01, 2009, from Food and Agricultural
Organization of the United Nations:
http://www.fao.org/docrep/003/x6878e/x6878e00.HT
M
Figure 3. Mean number of flowers of RCBr grown in
conventional soil (4.08 0.423 flowers (n=35) and
organic soil (2.51 0.115 flowers (n=39). (p=
0.00045796).
Carolina Lab Supply. (2009). Wisconsin Fast Plants
Standard Brassica rapa Seed. Retrieved September 15,
2009, from
http://www.carolina.com/product/158804.do?KickerID
=int_t_sgt_wfp_brassicarapaseed
96
Saddleback Journal of Biology
Spring 2010