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 (7) Citing Articles via Google Scholar Google Scholar Articles by Stone, J. L. Articles by Blomberg, C. P. Search for Related Content PubMed Articles by Stone, J. L. Articles by Blomberg, C. P. Agricola Articles by Stone, J. L. Articles by Blomberg, C. P. Social Bookmarking                            What's this?

Variation in the self-incompatibility response within and among populations of the tropical shrub Witheringia solanacea (Solanaceae)¹

Department of Biology, 5720 Mayflower Hill Dr., Colby College, Waterville, Maine 04901 USA

ABSTRACT

Breakdown of genetically enforced self-incompatibility (SI), an extremely common and important evolutionary transition in plants, has conventionally been conceived as a qualitative rather than a quantitative change. We evaluated qualitative and quantitative variation in SI for four populations of Witheringia solanacea in Costa Rica, examining growth of self-pollen tubes in pollinations of buds and mature flowers. We also measured levels of RNase production in styles to determine whether enzyme production was correlated with differences in self-rejection. The two small populations contained both self-compatible (SC) individuals and obligate outcrossers (female or SI). Plants in the two large populations were uniformly SI as revealed by pollen tube growth, although several of these individuals sporadically set seed autogamously. Stylar RNase activity did not differ significantly between bud and mature flowers, but self-pollen tube growth did differ, suggesting that a gene product in addition to S-RNase is responsible for developmental onset of SI. Population-level differences in RNase activity were consistent with differences in the strength of the rejection response in bud pollinations, suggesting that a threshold level of S-RNase, in combination with other factors, is necessary for SI. Our results support a growing body of evidence that not only qualitative variation in SI, but also quantitative variation may be functionally significant.

Key Words: Costa Rica • mating system • pollen tubes • self-compatibility • self-incompatibility • Solanaceae • S-RNase • Witheringia

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

This article has been cited by other articles:

				S. Knapp On 'various contrivances': pollination, phylogeny and flower form in the Solanaceae Phil Trans R Soc B, February 12, 2010; 365(1539): 449 - 460. [Abstract] [Full Text] [PDF]

				J. I. Mena-Ali and A. G. Stephenson Segregation Analyses of Partial Self-Incompatibility in Self and Cross Progeny of Solanum carolinense Reveal a Leaky S-Allele Genetics, September 1, 2007; 177(1): 501 - 510. [Abstract] [Full Text] [PDF]