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

What's this?

This Article Full Text Full Text (PDF) 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 Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (2) Citing Articles via Google Scholar Google Scholar Articles by Sage, T. L Articles by Waser, N. M Search for Related Content PubMed Articles by Sage, T. L Articles by Waser, N. M Agricola Articles by Sage, T. L Articles by Waser, N. M Social Bookmarking                            What's this?

Self-sterility in Ipomopsis aggregata (Polemoniaceae) is due to prezygotic ovule degeneration¹

²Department of Botany, University of Toronto, Toronto, Ontario, Canada M5S 3B2 ³Department of Biology, University of California, Riverside, California 92521 USA; and Rocky Mountain Biological Laboratory, Crested Butte, Colorado 81224 USA

ABSTRACT

Based on previous studies, extreme (>99%) self-sterility in scarlet gilia (Ipomopsis aggregata) appears to be involved in late-acting ovarian self-incompatibility (OSI). Here, we confirm this suggestion by comparing structural events that follow from cross- vs. self-pollinations of I. aggregata. Growth of cross- and self-pollen tubes in the style at 11 h and growth in the ovary at 24 h was equivalent. Nonetheless, by 24 h, cross-pollen effected a significantly higher percentage of both ovule penetration and fertilization. Ovules in self-pollinated flowers showed pronounced changes, including an absence of embryo sac expansion and reduced starch in the integument, by 11 h post-pollination, well before pollen tube entry into the ovary. In addition, the integumentary tapetum and adjacent 1–3 cell layers exhibited abnormal cell division, pronounced deposition of thick, pectin-rich cell walls, and cellular collapse. Ovules and embryo sacs from cross-pollinated flowers rarely showed such features. Developmental changes in ovules from self-pollinated flowers eventually resulted in integument and embryo sac collapse, a process not observed in ovules of unpollinated flowers. We suggest that OSI involves long-distance signaling between self-pollen or self-pollen tubes and carpel tissue that reduces availability of receptive ovules for fertilization before pollen tubes arrive in the ovary.

Key Words: histology • long-distance signaling • ovarian self-incompatibility (OSI) • ovular collapse • Polemoniaceae • Rocky Mountain Biological Laboratory • self-incompatibility

CiteULike    Complore    Connotea    Del.icio.us    Digg    Facebook    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				F. J. Valtuena, T. Rodriguez-Riano, F. Espinosa, and A. Ortega-Olivencia Self-sterility in two Cytisus species (Leguminosae, Papilionoideae) due to early-acting inbreeding depression Am. J. Botany, January 1, 2010; 97(1): 123 - 135. [Abstract] [Full Text] [PDF]

				G. Vaughton and M. Ramsey Floral emasculation reveals pollen quality limitation of seed output in Bulbine bulbosa (Asphodelaceae)1 Am. J. Botany, January 1, 2010; 97(1): 174 - 178. [Abstract] [Full Text] [PDF]