Recently our class looked at the Society for Economic Botany
website. We each chose an article that had been published in the Journal. I
chose on titled “Morphometric Analysis of Sunflower Achenes from Mexico and
Eastern North America.” This article was written by Somayeh S. Tarighat, David
L. Lentz, Stephen F. Matter and Robert Bye. This article was published in 2011,
in Volume 65, Number 3 of the Journal. The authors are scientists at the
University of Cincinnati and the Universidad Nacional Autónoma de México.
Sunflowers have played a major role in the evolution of
agricultural systems in the Americas. They are a major oilseed crop. These
scientists wanted to study the difference in sunflower seeds from varying
locations and how they have changed over time. Recently, ancient domesticated
sunflower seeds were found in Mexico, which caught the scientists attention and
this were included in the study. Mexican domesticated seeds have not been
studied in great detail, opposite of the American varieties.
Essentially, the goals of the study were to analyze the
difference in old and new sunflower seeds, and also wild and domesticated seeds
from Eastern North America and Mexico, and also to determine how useful the
computer assisted shape measurements were in classifying the seeds. The answers
to these inquiries will help us understand cultures of pre-Columbian Americas
and also show how the seeds have changed from that era to the present time.
In regards to the classification process, the computer
generated process would greatly benefit future research if it proves to be more
effective than the traditional methods. Pictures are taken of the seeds and analyzed
through the software. In this study, many different aspects of the seeds were
analyzed. These include form factor, roundness, curl, solidity, length, width,
and convexity. The data was run through statistical analysis. Assessing the
utility of these factors in discriminating between the seeds was one of the
principle objectives of the study. The scientists wanted to see if there was a significant
difference between Mexico and Eastern North America populations.
The result of the study revealed that the size factors
contributed significantly to the discriminating factors between the different
groups. Modern wild Eastern North America sunflowers are much larger than
modern Mexican sunflowers. Indigenous domesticated seeds from Mexico are
smaller than domesticated seeds from North America. Essentially, North America
has larger seeds, thus larger sunflowers, than Mexico. However, the
archeological seeds told a different story. The Mexican seeds were actually
larger than the Eastern North American seeds. Why is this though? The
scientists intend to do more research to determine why.
The scientists also concluded that the shape analysis
techniques using the computer software are less effective than the techniques
used in conventional methods to distinguish between different sunflower
populations. The results did reveal that wild populations showed higher
variability in size, both within and between populations. Also, a relation was
noted between seed size and the temperature of the climate in which they grow,
but not rainfall or elevation.
In regards to why I chose this article, it caught my
attention as I was scrolling through the many articles because it seemed
interesting to me. I’m partial to flowers, and most of my projects for this
class have been about flowers instead of other plants. Also, after reading the
article, I found it interesting that the new computer method of seed analysis
was determined to be less effective. I figured the computer method would make
the process more efficient. If it does prove to be helpful in the future, it
would be beneficial for much more research beyond just sunflowers. Also, I’m
curious as to why the trend in the size of the seeds has changed over time.
Overall, this was a very interesting article to read.
