Plant Reproduction and Optimal Foraging: Experimental Nectar Manipulations in Delphinium Nelsonii

Zimmerman, Michael J.

doi:10.2307/3544346

Cited by 131 publications

(98 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Nectar amount and concentration can both affect pollinator response, in such a manner that can influence plant reproductive success (Whitney and Glover 2007). Several studies have also shown that flowers that offer larger quantities of nectar can receive more pollinator visits than others (Zimmerman 1983;Real and Rathcke 1991;Mitchell 1993;Hodges 1995). In the present study, some A. aestivus flowers contained no nectar at all due to the herbivore activity.…”

Section: Discussionmentioning

confidence: 59%

“…These plants secreted lower amounts of nectar under dehydration conditions. Furthermore, Zimmerman (1983) found that watered plants of Delphinium nelsonii produced significantly more nectar per flower than the un-watered controls. Other studies have also shown that water availability, in years of higher precipitation or under irrigation, increased nectar production (Wyatt et al 1992;Petanidou et al 1999;Keasar et al 2008) or decreased sugar concentrations (Petanidou et al 1995).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Herbivory by sucking mirid bugs can reduce nectar production in Asphodelus aestivus Brot.

Samocha

Sternberg

2010

Arthropod-Plant Interactions

View full text Add to dashboard Cite

This experimental study focused on the effects of a mirid bug herbivore, Capsodes infuscatus on the flower nectar yield of a Mediterranean geophyte, Asphodelus aestivus. The effects of increasing densities of adult C. infuscatus bugs on A. aestivus, on the nectar volume and concentration were examined. Significant decreases were found in the number of flowers and nectar production as C. infuscatus densities increased. Analysis of covariance (ANCOVA) showed that nectar production was not affected by environmental variables (air temperature, relative air humidity and day-time) that were treated as covariates for the various bug herbivory intensities. Sugar concentration did not vary significantly among treatments, indicating that abiotic conditions were not responsible for differing nectar amounts. In light of A. aestivus's dependence on pollinator visits to produce seeds, we conclude that C. infuscatus could impair pollination success by reducing the amount of nectar in flowers. To the best of our knowledge, the present study is the first to show that insect herbivores do not necessarily have to remove segments from the flower in order to decrease nectar secretion.

show abstract

Section: Discussionmentioning

confidence: 59%

Section: Discussionmentioning

confidence: 99%

Herbivory by sucking mirid bugs can reduce nectar production in Asphodelus aestivus Brot.

Samocha

Sternberg

2010

Arthropod-Plant Interactions

View full text Add to dashboard Cite

show abstract

“…Many other hummingbird species also increase visit rates to real or artificial flowers with higher rewards, when visual cues are either present (Zimmerman 1983;Melendez-Ackerman et al 1997) or absent (Miller et al 1985;Hurly 1996;Irwin 2000). Preferences for more-rewarding flowers are also observed in other pollinator taxa, such as bumblebees and honeybees (e.g.…”

Section: Discussion (A) Sexual Selection Hypothesesmentioning

confidence: 99%

Hummingbird responses to gender-biased nectar production: are nectar biases maintained by natural or sexual selection?

Carlson

2008

Proc. R. Soc. B.

View full text Add to dashboard Cite

Pollinators mediate the evolution of secondary floral traits through both natural and sexual selection. Gender-biased nectar, for example, could be maintained by one or both, depending on the interactions between plants and pollinators. Here, I investigate pollinator responses to gender-biased nectar using the dichogamous herb Chrysothemis friedrichsthaliana (Gesneriaceae) which produces more nectar during the male floral phase. Previous research showed that the hummingbird pollinator Phaethornis striigularis visited male-phase flowers more often than female-phase flowers, and multiple visits benefited male more than female fecundity. If sexual selection maintains male-biased rewards, hummingbirds should prefer morerewarding flowers independent of floral gender. If, however, differential rewards are partially maintained through natural selection, hummingbirds should respond to asymmetry with visits that reduce geitonogamy, i.e. selfing and pollen discounting. In plants with male biases, these visit types include single-flower visits and movements from low to high rewards. To test these predictions, I manipulated nectar asymmetry between pairs of real or artificial flowers on plants and recorded foraging behaviour. I also assessed maternal costs of selfing using hand pollinations. For plants with real flowers, hummingbirds preferred more-rewarding flowers and male-phase morphology, the latter possibly owing to previous experience. At artificial arrays, hummingbirds responded to extreme reward asymmetry with increased single-flower visits; however, they moved from high to low rewards more often than low to high. Finally, selfed flowers did not produce inferior seeds. In summary, sexual selection, more so than geitonogamy avoidance, maintains nectar biases in C. friedrichsthaliana, in one of the clearest examples of sexual selection in plants, to date.

show abstract

“…Nectar production rate frequently varies strongly with abiotic factors (e.g. Kenoyer, 1917;Pleasants, 1983;Zimmerman, 1983;Plowright, 1987; D. C. Campbell & K. J. Halama, unpublished data), and such large environmental influences might be expected to mask any heritable variation. Our results argue against the generality of that inference, and bolster the argument that phenotypic selection might influence the evolution of nectar production rate (Zimmerman, 1988;Mitchell, 1993).…”

Section: Discussionmentioning

confidence: 99%

Heritability of floral traits for the perennial wild flower Penstemon centranthifolius (Scrophulariaceae): clones and crosses

1993

View full text Add to dashboard Cite

Floral and reproductive traits frequently influence pollinator behaviour and plant reproductive success and are therefore thought to be under selection. However, for wild plant populations there is little information on the amount of genetic variation for such traits. We estimated broad-and narrow-sense heritability of floral and reproductive traits for two populations of the perennial wildflower Penstemon centranthifolius, using a paternal half-sib crossing design in one case, and clonal propagation of ramets from different genets in the other. In both designs, most traits were significantly heritable, including nectar production, corolla length and width, inflorescence length and total flower production. Flowering date was significantly heritable for the crosses, but not for the clones, while nectar sugar concentration was not significantly heritable in either design. Genetic correlations were in some cases strong, and in some cases differed greatly from the corresponding phenotypic correlations. These results indicate that P. centranthifolius harbours a large reservoir of genetic variance which could support an evolutionary response to phenotypic selection.

show abstract

Plant Reproduction and Optimal Foraging: Experimental Nectar Manipulations in Delphinium Nelsonii

Cited by 131 publications

References 29 publications

Herbivory by sucking mirid bugs can reduce nectar production in Asphodelus aestivus Brot.

Herbivory by sucking mirid bugs can reduce nectar production in Asphodelus aestivus Brot.

Hummingbird responses to gender-biased nectar production: are nectar biases maintained by natural or sexual selection?

Heritability of floral traits for the perennial wild flower Penstemon centranthifolius (Scrophulariaceae): clones and crosses

Contact Info

Product

Resources

About