Data from: Pollination and fruit set in two rewardless slipper orchids and their hybrids (Cypripedium, Orchidaceae): large yellow flowers outperform small white flowers in the northern tall grass prairie

Grantham, M. A.

Ford, B. A.

Worley, A. C.

Published Jul 05, 2020 on Dryad. https://doi.org/10.5061/dryad.2bg7pk5

Cite this dataset

Grantham, M. A.; Ford, B. A.; Worley, A. C. (2020). Data from: Pollination and fruit set in two rewardless slipper orchids and their hybrids (Cypripedium, Orchidaceae): large yellow flowers outperform small white flowers in the northern tall grass prairie [Dataset]. Dryad. https://doi.org/10.5061/dryad.2bg7pk5

Abstract

• Species with rewardless flowers often have low fruit to flower ratios, although wide temporal and spatial variation in fruiting success can occur. We compared floral phenotypes, insect visitors, and fruiting success in four populations of the small white (Cypripedium candidum) and yellow lady’s slipper orchids (C. parviflorum) and their hybrids near the northern extent of North America’s tall grass prairie. • Flower and fruit numbers were observed for two seasons on marked individuals (n = 1811). Floral traits were measured on 82-140 individuals per taxon, and analyzed in relation to fruiting success. All insects found inside flowers were collected, inspected for pollen smears, and measured for comparison to floral features. • Among orchid taxa, C. candidum had the smallest flowers, lowest number and variety of insect visitors, and lowest fruit to flower ratios. These measures were intermediate in hybrids and highest in C. parviflorum, despite low flower numbers in the latter. Within orchid taxa, fruit number was positively related to flower number, but fruit to flower ratios decreased slightly, as would be expected if pollinators left unrewarding patches. Potential pollinators included the dipteran Odontomyia pubescens and hymenopterans Andrena spp., Apis mellifera, and Lasioglossum zonulum. • Cypripedium parviflorum had a reproductive advantage over C. candidum across multiple populations and years. Hybrids showed segregation for floral traits, and hybrid fruiting success increased with a deeper intensity of yellow pigment and larger escape routes for floral visitors. These same attributes likely contributed to the relatively high fruit set in C. parviflorum in the study region.

Usage notes

Cypripedium flower measurements 2010 2011

367 genets with a complete set of floral measurements. Flower colour ranged from 1 (white) to 8 (deep yellow). Data correspond to Fig. 2, Fig 3 and Table S2. 337 genets have fruiting data. These data correspond to Fig. 6 and Table S3.

Cypripedium fruiting survey 2010 2011

Flowering and Fruiting data for 1811 genets. Data correspond to Fig. 4, Fig. 5, and Table S3

Cypripedium insect visitors 2010 2011

Measurements of 117 insect visitors found in Cypripedium flowers. Of these 112 had complete data. Data for the most common insect taxa (n=96) are in Table 1 and Fig. 3. Body width in the Figure refers to insect abdominal width. Pollen smears were on the thorax unless otherwise noted. A yes for exit success indicates direct observation of an insect leaving a flower through the exit (see description in text).

Location

Canada

Manitoba

tall grass prairie