Viola L. are the larval food plants for a charismatic group of butterflies in Speyeria Scudder, 1872, which contains several rare and declining taxa in California and across North America. A current impediment to restoring Viola in California is a lack of knowledge of germination requirements. In this study we focused on determining conditions for successful germination of V. pedunculata Torr. & A. Gray, the food plant of the federally listed endangered Speyeria callippe (Boisduval, 1852) subsp. callippe, and V. purpurea Kellogg subsp. quercetorum (M.S. Baker & J.C. Clausen) R.J. Little, the food plant of the imperiled southern Coast Range butterfly, S. adiaste (Edwards, 1864) subsp. clemencei (Comstock, 1925). We examined the effects of gibberellic acid, seed color, elaiosome removal, and duration of stratification on germination success. We found that both taxa germinate exceptionally well (73–100%) after a prolonged period of after-ripening and 6–10 wk of stratification. Gibberellic acid and elaiosome removal did not have strong effects on germination of V. pedunculata, and both dark and mottled V. purpurea subsp. quercetorum seeds germinated equally well. We make recommendations for successful lab germination of these two native violets, setting the stage for additional research to help restore their populations as well as their herbivores.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 64 • No. 1