Flowering Dates of Viola sororia Willd. and V. pensylvanica Michx. at Different Latitudes

Authors

Theodore A. McConnell, Grinnell College
Norman H. Russell, Grinnell CollegeFollow

Document Type

Research

Abstract

The response to daylength has been shown to be significant in the initiation of flowering in many species of vascular plants. Herbarium specimens of Viola sororia Willd. and V. pensylvanica Michx. from a wide range of latitudes were examined to ascertain correlation between dates of flowering and length of day. Two observations were made: the higher the latitude, the later flowering occurred in the spring; and the higher the latitude the greater the daylength at the time of open flowering. It is suggested that these north-south clines represent a genetic response arrived at through natural selection. Further studies arc proposed to test this hypothesis.

Publication Date

1959

Journal Title

Proceedings of the Iowa Academy of Science

Volume

66

Issue

1

First Page

178

Last Page

184

Copyright

©1959 Iowa Academy of Science, Inc.

Language

en

File Format

application/pdf

Recommended Citation

McConnell, Theodore A. and Russell, Norman H. (1959) "Flowering Dates of Viola sororia Willd. and V. pensylvanica Michx. at Different Latitudes," Proceedings of the Iowa Academy of Science, 66(1), 178-184.
Available at: https://scholarworks.uni.edu/pias/vol66/iss1/25