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Abstract: We examined the response of Solanum carolinense and its pollinators to experimentally elevated soil salinity. We examined sodlium levels in pollen, pollen viability, and pollinator visitation.The "Soil Sodium and Moisture" data set contains data from 59 soil samples.Samples came from the root zone of Solanum carolinense that were either treated ("salt") with a brine solution ("S") or a distilled water control ("W"). We took soil cores and measured wet mass ("wet_mass") and dry mass ("dry_mass)" in grams and calculated the proportion of moisture in each sample ("proportion_moisture") as the difference in mass divided by the wet mass. The sodium concentration (ppm) in the soil samples ("Na_ppm") was estimated with a conductivity meter.The "Pollen Cations" data set contains estimates of sodium ("Na"), potassium ("K"), magnesium ("Mg"), and calcium ("Ca") in 28 Solanum carolinense pollen samples. Each sample was weighed to the nearest milligram ("pollen_mass") and diuluted in distilled water. The total sample mass was measured ("sample_mass"), and cation concentrations (mg/L) using a Thermo Scientific Dionex ICS-3000 IC ion exchange chromatograph.The "Pollen Viability" data set contains estimates of viable and inviable pollen grains in 41 Solanum carolinense pollen samples. Each pollen sample came from a single plant ("plant"), and plants were treated ("salt") with either a brine solution ("S") or a distilled water control ("W"). Pollen samples were stained with aniline blue in lactophenol. Fully stained pollen grains were scored as "viable," and unstained grains were scored as "inviable."The Pollinator Observations data set contains data on bumble bee (Bombus) visitation to Solanum carolinense plants ("plant") that were treated ("salt") with either a brine solution ("S") or distilled water ("W"). Observation durations were always 30 minutes per plant. Two observers recorded observations simultaneously on either an "S" or "W" treated plant. The data set includes the "month" (6 = June), "day," "year," and "time" of the observation (all times are am). We recorded the total number of open flowers ("flowers") on each focal plant, and for each bumble bee visiting the plant ("bee"), we recorded the number of times the bee alighted on the flower ("visits"). If a plant was not visited by a bumble bee during the 30-minute observation period, the "bee" indentification was given a value of 0. The "visited" column indicates whether the plant was visited ("1") by a bumble bee during the 30-minute observation period or was not ("0").
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This content will become publicly available on July 1, 2027
Soil salinity effects on pollen and pollinator visitation in a buzz‐pollinated glycophyte, Solanum carolinense
Abstract PremiseHuman activity has significantly altered the salt cycle, affecting an estimated 2.5 billion acres of soil worldwide. Elevated soil salinity is a well‐known plant stressor, but it may also affect interactions between plants and insects, which are often sodium limited. Elevated sodium in nectar can increase pollinator visitation, but no previous study has examined the effects of elevated soil salinity on visitation by pollen‐collecting bees. MethodsOur study tested whether increased soil salinity impacts pollen sodium andBombusspp. visitation toSolanum carolinense, a buzz‐pollinated perennial wildflower that rewards pollinators only with pollen. Soil salinity around the root zone ofSolanum carolinensegrowing wild in an early successional field was artificially increased with a salt solution to observe changes in pollen sodium and other cations, pollen viability, and pollinator visitation. ResultsSalt addition to the soil increased soil salinity by over five‐fold, but there was no effect on the sodium levels ofS. carolinensepollen. The salt treatment had no effect on pollinator visitation or pollen viability. ConclusionsAlthough high soil salinity has been shown to increase nectar sodium levels and thus pollinator visitation, we infer from our results thatS. carolinenseis able to largely exclude sodium from its pollen, preventing high salinity soil from affecting pollinator attraction and pollen viability.
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- Award ID(s):
- 1659816
- PAR ID:
- 10704080
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- American Journal of Botany
- Volume:
- 113
- Issue:
- 7
- ISSN:
- 0002-9122
- Format(s):
- Medium: X
- Associated Dataset(s):
- View Associated Dataset(s) >>
- Sponsoring Org:
- National Science Foundation
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