Are Reproductive Traits Related to Pollen Limitation in Plants? A Case Study from a Central European Meadow

Abstract

The deficiency of pollen grains for ovule fertilization can be the main factor limiting plant reproduction and fitness. Because of the ongoing global changes, such as biodiversity loss and landscape fragmentation, a better knowledge of the prevalence and predictability of pollen limitation is challenging within current ecological research. In our study we used pollen supplementation to evaluate pollen limitation (at the level of seed number and weight) in 22 plant species growing in a wet semi-natural meadow. We investigated the correlation between the pollen limitation index (PL) and floral traits associated with plant reproduction or pollinator foraging behavior. We recorded significant pollen limitation for approximately 41% of species (9 out of 22 surveyed). Seven species had a significant positive response in seed production and two species increased in seed weight after pollen supplementation. Considering traits, PL significantly decreased with the number of pollinator functional groups. The relationship of PL with other examined traits was not supported by our results. The causes of pollen limitation may vary among species with regard to (1) different reproductive strategies and life history, and/or (2) temporary changes in influence of biotic and abiotic factors at a site.

Pollen limitation failing reproductive success in selected animal pollinated trees of tropical moist deciduous forest of north-eastern hill region, India

“…The supplementation of pollen was found to be increasing the fruit and seed set significantly in all five studied species. Confirmation from earlier studies implies that supplementation of pollen enhances the fruit/seed set, size and weight of a seed in a flower (Campbell, 1993;Yang et al, 2005;Gómez et al, 2010;Bartoš et al, 2020). Pollen limitation was the resultant of both limited pollen quantity and quality (Colling et al, 2004).…”

The significance of reproduction-related traits for wet meadow species survival in a fragmented landscape

“…We excluded ants as they are not considered to be e cient pollinators in the temperate grasslands (Wills et al 2018). For details on the sampling method on the pollinators visitation see in Bartoš et al (2020a).…”

Pollinator‐mediated effects of landscape‐scale land use on grassland plant community composition and ecosystem functioning – seven hypotheses

“…Another part may be due to the evolution of a bet‐hedging strategy in response to stochastic pollinator availability, where ovules are oversupplied compared to the average pollen loads (Burd, 2008). While pollen limitation is expected to be lower in long‐lived, clonal and less‐specialised plant species (Ashman et al ., 2004; Barrett, 2015; Bartos et al ., 2020; Bennett et al ., 2018; Hegland & Totland, 2008; Larson & Barrett, 2000), evidence for links between such traits and pollen limitation is very heterogeneous (Larson & Barrett, 2000) for reasons that may include contrasting methods and scales, as well as dependence on context such as pollinator availability (Lázaro, Lundgren & Totland, 2015).…”

“…Studies that include multiple species in grassland communities (Bartos et al ., 2020; Bennett et al ., 2018; Hegland & Totland, 2008; Lázaro et al ., 2015) report the share of pollen‐limited species under the period of investigation to range from 0% (Bennett et al ., 2018) to around 41% (Bartos et al ., 2020). This is likely a conservative estimate as the power to detect pollen limitation may be low when a limited number of individuals (<40) is assessed per species (Thomson, 2001) (Bennett et al ., 2018: 3–10; Lázaro et al ., 2015: 15; Hegland & Totland, 2008: 15–20; Bartos et al ., 2020: 20–30).…”

“…Studies that include multiple species in grassland communities (Bartos et al ., 2020; Bennett et al ., 2018; Hegland & Totland, 2008; Lázaro et al ., 2015) report the share of pollen‐limited species under the period of investigation to range from 0% (Bennett et al ., 2018) to around 41% (Bartos et al ., 2020). This is likely a conservative estimate as the power to detect pollen limitation may be low when a limited number of individuals (<40) is assessed per species (Thomson, 2001) (Bennett et al ., 2018: 3–10; Lázaro et al ., 2015: 15; Hegland & Totland, 2008: 15–20; Bartos et al ., 2020: 20–30). Herbaceous species, species occurring in temperate regions, and species occurring in open habitats have somewhat lower levels of pollen limitation (Larson & Barrett, 2000), suggesting that temperate grasslands may exhibit lower levels of pollen limitation than other habitats.…”