Date of Graduation


Document Type


Degree Name

Bachelor of Science

Degree Level



Biological Sciences


Goggin, Fiona

Committee Member/Reader

Aloia, Lindsey

Committee Member/Second Reader

Stephenson, Steven

Committee Member/Third Reader

Pare, Adam


Plant elicitor peptides (Peps) – endogenous chains of amino acids involved in natural plant defense – have been shown to decrease damage from herbivores and pathogens by inducing an immune response, increasing the emission of volatile organic compounds (VOCS), transcripts, and metabolites. Exogenous treatment of soybean seeds with plant elicitor peptide GmPep3 has been shown to induce these broad-spectrum defenses and offers a new method for increasing crop yield. However, the effects of GmPep3 on indicators of soybean health – root characteristics, growth stages, etc. – have not been fully realized.

Using the root-phenotyping platform RhizoVision Explorer, several root traits of soybean plants treated with GmPep3 were analyzed to determine whether there was a statistically significant difference between the roots of plants treated with peptide and without peptide. These root traits included total number of root tips, total root length (mm), and surface area (mm2). Two concentrations of peptide were studied as well to determine whether increasing or decreasing the amount of GmPep3 would have an effect on chosen root characteristics.

Results indicated that there did not appear to be a statistically significant difference in the number of root tips between plants treated with GmPep3 and those not treated with GmPep3. There were, however, observed differences in total root length and surface area between treated and untreated seeds during one repetition of the experiment. However, these differences were no longer statistically significant by the end of the experimental period, indicating that although plant growth was initially impacted by the addition of the peptide treatment, these effects were no longer present by the end of the growing period. Increasing the concentration of GmPep3 did not appear to have a significant impact on root growth. Future studies with a larger sample size, longer growing period, more varied root characteristics, and different concentrations of GmPep3 are necessary to uphold the hypothesis that GmPep3 does not negatively impact soybean root growth.


soybean, phenotyping, peptide, roots, pesticide