Evaluation of Freezing Tolerance in Solanum sitiens Introgression Lines
Tomato is a nutritionally and economically significant crop worldwide, providing an excellent source of antioxidants, vitamin C, and vitamin A. However, its vulnerability to low temperatures restricts the growing season and leads to decreased yields due to late frost. Solanum sitiens, a wild tomato relative endemic to the Atacama desert in Northern Chile, is able to tolerate drought, high salinity, and freezing temperatures in its native environment (Chetelat et al. 2019). In this project, a population of introgression lines that each contain a different chromosome segment from S. sitiens were screened to determine if this wild species can confer freezing tolerance to cultivated tomato. Plants were subjected to a frost treatment in a cold chamber and the resulting frost damage was evaluated on a qualitative scale. The frost damage of the introgression lines was compared to that of the domestic parent in order to identify lines with increased tolerance to freezing temperatures. The accumulation of proline, an amino acid, is associated with abiotic stress response and recovery in plants. The change in proline was measured to determine if there is a significant difference in proline accumulation for plants that are more tolerant to freezing temperatures. Proline absorbance was measured before and after the frost treatment using an acid-ninhydrin colorimetric assay. Identifying frost-resistant tomato lines would allow growers to plant earlier and minimize losses due to frost, thereby increasing yields.
As an intern in the Vogel lab this summer I gained a deeper understanding of plant genomics and research techniques. Additionally, I became more comfortable with designing experiments and statistical analysis in R. It was rewarding to contribute to a project that has the potential for application within the agricultural sector as I am passionate about food security. This summer I was also able to assist with multiple projects taking place in the lab, giving me exposure to many aspects of plant breeding research such as plant pathology and field trials. Above all, this experience has shown me what it is like to carry out an independent research project, from designing and executing experiments to analyzing and presenting the results. This program has made me a more capable researcher and I now feel more prepared for graduate school. I would like to thank the members of the Vogel lab for sharing their knowledge and providing great support and mentorship.