Determining the Cyanogenic Potential of Two Land Races of Lima Bean, Phaseolus lunatus
Grade Level at Time of Presentation
Junior
Major
Biology/Public Health
Minor
Latin American and Latino Studies
Institution
University of Louisville
KY House District #
50
KY Senate District #
14
Faculty Advisor/ Mentor
Christopher J. Frost, PhD
Department
Department of Biology
Abstract
Determining the Cyanogenic Potential of Two Land Races of Lima Bean, Phaseolus lunatus
Maria Shields, Grace Freundlich, Christopher Frost
University of Louisville
Plants use a variety of chemical mechanisms to defend themselves against insect herbivory. One example of a potent chemical defense is cyanide, which occurs in a number of plant higher taxa, including various legume species. In these plants, cyanide is stored in undamaged plant cells as cyanogenic glycosides (CG), in which cyanide is conjugated with a hexose monosaccharide; cyanide is released when plant tissue is damaged and the CGs interact with beta-glucosidase. The purpose of our study was to determine the cyanogenic potential (CP) of two cultivated varieties of lima bean, Phaseolus lunatus. We have adapted a previously established CP protocol for use with small sample volumes. We were able to establish a wide concentration range of linear responses for the CP protocol, and initially have shown CP of ~150 micromoles per gram in field lima bean leaves. We are now using this protocol to assess whether CP is inducible in lima bean plants attacked by two different species of insect herbivores, the beet armyworm (Spodoptera exigua) and the velvetbean worm (Anticarsia gemmatalis). Quantifying plant defense chemistry is essential for understanding ecological interactions and their impact on human health.
Determining the Cyanogenic Potential of Two Land Races of Lima Bean, Phaseolus lunatus
Determining the Cyanogenic Potential of Two Land Races of Lima Bean, Phaseolus lunatus
Maria Shields, Grace Freundlich, Christopher Frost
University of Louisville
Plants use a variety of chemical mechanisms to defend themselves against insect herbivory. One example of a potent chemical defense is cyanide, which occurs in a number of plant higher taxa, including various legume species. In these plants, cyanide is stored in undamaged plant cells as cyanogenic glycosides (CG), in which cyanide is conjugated with a hexose monosaccharide; cyanide is released when plant tissue is damaged and the CGs interact with beta-glucosidase. The purpose of our study was to determine the cyanogenic potential (CP) of two cultivated varieties of lima bean, Phaseolus lunatus. We have adapted a previously established CP protocol for use with small sample volumes. We were able to establish a wide concentration range of linear responses for the CP protocol, and initially have shown CP of ~150 micromoles per gram in field lima bean leaves. We are now using this protocol to assess whether CP is inducible in lima bean plants attacked by two different species of insect herbivores, the beet armyworm (Spodoptera exigua) and the velvetbean worm (Anticarsia gemmatalis). Quantifying plant defense chemistry is essential for understanding ecological interactions and their impact on human health.