Responsive nectar secretion in Scrophularia californica
Graduation Date
2007
Document Type
Thesis
Program
Other
Program
Thesis (M.A.)--Humboldt State University, Biology, 2007
Committee Chair Name
Michael Mesler
Committee Chair Affiliation
HSU Faculty or Staff
Keywords
Nectar secretion, Scrophulariaceae, Humboldt State University -- Theses -- Biology, Scrophularia californica, Nectar
Abstract
This study explores nectar production in Scrophularia californica, a native California herbaceous perennial. I conducted a series of field experiments to determine whether S. californica can replenish nectar in response to extractions, whether the rate of nectar production varies as a function of sexual phase, how much independence flowers exhibit in nectar production, whether nectar refills and ceases on attaining an optimum level or set point, and whether nectaries can regulate the principal components of nectar. Sugar content of nectar was determined using the anthrone method of carbohydrate analysis. S. californica demonstrates nectar replenishment 2.5 times greater when hourly removals are made, some degree of independence in nectar production, similar rates of nectar secretion during sexual phases, no apparent set point after refilling and the capacity for regulating sugar and water in nectar. Nectar may not be as costly for S. californica as it is for other species, or its costs may be offset by the certainty of high pollinator visitation which may obviate additional regulatory mechanisms.
Recommended Citation
Morris, Rosemary, "Responsive nectar secretion in Scrophularia californica" (2007). Cal Poly Humboldt theses and projects. 1790.
https://digitalcommons.humboldt.edu/etd/1790
https://scholarworks.calstate.edu/concern/theses/w0892d429