HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Supplemental Data Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (32) Citing Articles via Google Scholar Google Scholar Articles by Armbruster, W. S. Articles by Nute, H. Search for Related Content PubMed Articles by Armbruster, W. S. Articles by Nute, H. Agricola Articles by Armbruster, W. S. Articles by Nute, H.

Comparative analysis of late floral development and mating-system evolution in tribe Collinsieae (Scrophulariaceae s.l.)¹

²Department of Botany, Norwegian University of Science and Technology, N-7491 Trondheim, Norway; ³Institute of Arctic Biology, University of Alaska, Fairbanks, Alaska 99775-7000 USA; ⁴Jepson Herbarium and Department of Integrative Biology, University of California, Berkeley, California 94720-2465 USA; ⁵Department of Biological Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 USA

Species of Collinsia and Tonella, the two sister genera of self-compatible annuals that constitute tribe Collinsieae, show extensive variation in floral size and morphology and in patterns of stamen and style elongation during the life of the flower (anthesis). We used a nuclear ribosomal ITS phylogeny, independent contrasts, and phylogenetically corrected path analysis to explore the patterns of covariance of the developmental and morphological traits potentially influencing mating system. Large-flowered taxa maintain herkogamy (spatial separation of anthers and stigmas) early in anthesis by differential elongation of staminal filaments, which positions each of the four anthers at the tip of the "keel" upon dehiscence. Small-flowered taxa do not show this pattern of filament elongation. The styles of large-flowered taxa elongate late in the 2–5 d of anthesis, resulting in late anther-stigma contact and delayed self-pollination. Anther-stigma contact and self-pollination occur early in anthesis in small-flowered species/populations. Thus, we found complex covariation of morphological and developmental traits that can be interpreted as the result of multitrait adaptation for early selfing and high levels of autogamy, delayed selfing and higher levels of outcrossing, or intermediate levels of outcrossing. Continuous variation in these traits suggests the operation of continuous variation in selective optima or the combined effects of divergent selection and phylogenetic inertia.

Key Words: autogamy • correlated evolution • Collinsieae • cross pollination • flower development • herkogamy • mating system • pollination • Scrophulariaceae • self-pollination

This article has been cited by other articles:

				R. D. Sargent, C. Goodwillie, S. Kalisz, and R. H. Ree Phylogenetic evidence for a flower size and number trade-off Am. J. Botany, December 1, 2007; 94(12): 2059 - 2062. [Abstract] [Full Text] [PDF]

				J. S. Miller and P. K. Diggle Correlated evolution of fruit size and sexual expression in andromonoecious Solanum sections Acanthophora and Lasiocarpa (Solanaceae) Am. J. Botany, October 1, 2007; 94(10): 1706 - 1715. [Abstract] [Full Text] [PDF]

				A. Lankinen, W. S. Armbruster, and L. Antonsen Delayed stigma receptivity in Collinsia heterophylla (Plantaginaceae): genetic variation and adaptive significance in relation to pollen competition, delayed self-pollination, and mating-system evolution Am. J. Botany, July 1, 2007; 94(7): 1183 - 1192. [Abstract] [Full Text] [PDF]

				I. A. Anderson and J. W. Busch Relaxed pollinator-mediated selection weakens floral integration in self-compatible taxa of Leavenworthia (Brassicaceae) Am. J. Botany, June 1, 2006; 93(6): 860 - 867. [Abstract] [Full Text] [PDF]

				A. L. Parachnowitsch and E. Elle Variation in sex allocation and male-female trade-offs in six populations of Collinsia parviflora (Scrophulariaceae s.l.) Am. J. Botany, August 1, 2004; 91(8): 1200 - 1207. [Abstract] [Full Text] [PDF]

				R. E. Miller, J. A. McDonald, and P. S. Manos Systematics of Ipomoea subgenus Quamoclit (Convolvulaceae) based on ITS sequence data and a Bayesian phylogenetic analysis Am. J. Botany, August 1, 2004; 91(8): 1208 - 1218. [Abstract] [Full Text] [PDF]

				E. Elle and R. Carney Reproductive assurance varies with flower size in Collinsia parviflora (Scrophulariaceae) Am. J. Botany, June 1, 2003; 90(6): 888 - 896. [Abstract] [Full Text] [PDF]