Pollen transfer from invasive Carpobrotus spp. to natives – A study of pollinator behaviour and reproduction success

Abstract Background Most orchid species have been shown to be severely pollination limited, and the factors affecting reproductive success have been widely studied. However, the factors determining the reproductive success vary from species to species. Habenaria species typically produce nectar but exhibit variable fruit set and reproductive success among species. Here, we investigated the influence of the flowering plant density, inflorescence size, breeding system, and pollinator behaviour on the reproductive success of two rewarding Habenaria species. Results Our observations indicated that Habenaria limprichtii and H. petelotii co-occur in roadside verge habitats and present overlapping flowering periods. Both species were pollination limited, although H. limprichtii produced more fruits than H. petelotii under natural conditions during the 3-year investigation. H. petelotii individuals formed distinct patches along roadsides, while nearly all H. limprichtii individuals clustered together. The bigger floral display and higher nectar sugar concentration in H. limprichtii resulted in increased attraction and visits from pollinators. Three species of effective moths pollinated for H. limprichtii, while Thinopteryx delectans (Geometridae) was the exclusive pollinator of H. petelotii. The percentage of viable seeds was significantly lower for hand geitonogamy than for hand cross-pollination in both species. However, H. limprichtii may often be geitonogamously pollinated based on the behaviours of the pollinators and viable embryo assessment. Conclusions In anthropogenic interference habitats, the behaviours and abundance of pollinators influence the fruit set of the two studied species. The different pollinator assemblages in H. limprichtii can alleviate pollinator specificity and ensure reproductive success, whereas the more viable embryos of natural fruit seeds in H. petelotii suggested reducing geitonogamy by pollinators in the field. Our results indicate that a quantity-quality trade-off must occur between species with different breeding strategies so that they can fully exploit the existing given resources.

Download Full-text

Trends in the pollination ecology of the Orchidaceae: evolution and systematics

Canadian Journal of Botany ◽

10.1139/b92-083 ◽

1992 ◽

Vol 70 (3) ◽

pp. 642-650 ◽

Cited By ~ 86

Author(s):

Raymond Louis Tremblay

Keyword(s):

Plant Species ◽

Evolutionary Ecology ◽

Evolutionary Significance ◽

Evolutionary Trend ◽

Pollen Transfer ◽

Orchid Species ◽

Pollinator Species ◽

Plant Taxon ◽

Pollinator Specialization ◽

The Cost

Reduction in the number of pollinator species per plant species is a mechanism that may lower the cost of pollen transfer. Using efficient pollinators may have an evolutionary significance. It is hypothesized that an evolutionary trend from many pollinators to few pollinators per plant species should be observable when species from ancestral versus recently derived monophyletic taxon are compared. Three different orchid phylogenetic sequences are used; two of the phylogenies show a reduction in the number of pollinator species per orchid species from the most ancestral to the most recently derived subfamilies. The third classification did not show this trend. It is thus possible to observe macroevolution of pollinator specialization of a monophyletic plant taxon. Key words: evolution, pollination, systematics, Orchidaceae, evolutionary ecology.

Download Full-text

Hawkmoths evaluate scenting flowers with the tip of their proboscis

eLife ◽

10.7554/elife.15039 ◽

2016 ◽

Vol 5 ◽

Cited By ~ 24

Author(s):

Alexander Haverkamp ◽

Felipe Yon ◽

Ian W Keesey ◽

Christine Mißbach ◽

Christopher Koenig ◽

...

Keyword(s):

Wind Tunnel ◽

Manduca Sexta ◽

Ecosystem Service ◽

Floral Scent ◽

Nicotiana Attenuata ◽

Floral Volatiles ◽

Pollen Transfer ◽

Olfactory Neurons ◽

Molecular Analyses ◽

Choice Tests

Pollination by insects is essential to many ecosystems. Previously, we have shown that floral scent is important to mediate pollen transfer between plants (<xref ref-type="bibr" rid="bib16">Kessler et al., 2015</xref>). Yet, the mechanisms by which pollinators evaluate volatiles of single flowers remained unclear. Here, Nicotiana attenuata plants, in which floral volatiles have been genetically silenced and its hawkmoth pollinator, Manduca sexta, were used in semi-natural tent and wind-tunnel assays to explore the function of floral scent. We found that floral scent functions to increase the fitness of individual flowers not only by increasing detectability but also by enhancing the pollinator's foraging efforts. Combining proboscis choice tests with neurophysiological, anatomical and molecular analyses we show that this effect is governed by newly discovered olfactory neurons on the tip of the moth's proboscis. With the tip of their tongue, pollinators assess the advertisement of individual flowers, an ability essential for maintaining this important ecosystem service.

Download Full-text

Pollen Transfer by Natural Hybrids and Parental Species in an Ipomopsis Hybrid Zone

Evolution ◽

10.2307/2411334 ◽

1998 ◽

Vol 52 (6) ◽

pp. 1602 ◽

Cited By ~ 22

Author(s):

Diane R. Campbell ◽

Nickolas M. Waser ◽

Paul G. Wolf

Keyword(s):

Hybrid Zone ◽

Parental Species ◽

Pollen Transfer ◽

Natural Hybrids

Download Full-text

Changes in reciprocal herkogamy during the tristyly-distyly transition in Oxalis alpina increase efficiency in pollen transfer

Journal of Evolutionary Biology ◽

10.1111/j.1420-9101.2012.02455.x ◽

2012 ◽

Vol 25 (3) ◽

pp. 574-583 ◽

Cited By ~ 18

Author(s):

F. BAENA-DíAZ ◽

J. FORNONI ◽

P. SOSENSKI ◽

F. E. MOLINA-FREANER ◽

S. G. WELLER ◽

...

Keyword(s):

Pollen Transfer ◽

Reciprocal Herkogamy ◽

Increase Efficiency

Download Full-text

Unilateral incompatibility and the effects of interspecific pollination for Erythronium americanum and Erythronium albidum (Liliaceae)

Canadian Journal of Botany ◽

10.1139/b93-038 ◽

1993 ◽

Vol 71 (2) ◽

pp. 353-358 ◽

Cited By ~ 41

Author(s):

Lawrence D. Harder ◽

Mitchell B. Cruzan ◽

James D. Thomson

Keyword(s):

Seed Production ◽

Pollen Tubes ◽

The Self ◽

Pollen Transfer ◽

Interspecific Incompatibility ◽

Unilateral Incompatibility ◽

Heterospecific Pollen ◽

Interspecific Pollen Transfer ◽

Erythronium Americanum ◽

Incompatibility Reaction

To determine whether interspecific pollen transfer could reduce seed production by two sympatric lilies, Erythronium albidum and Erythronium americanum, we hand-pollinated flowers with mixtures of conspecific and heterospecific pollen. These species exhibited typical unilateral interspecific incompatibility, i.e., pollen tubes from the self-infertile species (E. americanum) grew apparently unimpeded in styles of the self-fertile species (E. albidum), whereas the reverse cross resulted in an incompatibility reaction. Because of this asymmetrical relation and faster growth by heterospecific pollen tubes in E. albidum stigmas than by conspecific tubes, pollination with abundant heterospecific pollen reduced fruit and seed production by E. albidum, but not by E. americanum, as long as the stigma also received some conspecific pollen. Unilateral incompatibility could benefit self-infertile species in reproductive interactions with closely related self-fertile species; however, this benefit remains to be demonstrated for naturally pollinated plants. Key words: Erythronium albidum, Erythronium americanum, interspecific pollen transfer, pollination, unilateral incompatibility.

Download Full-text