Evaluation of sampling effort required to assess pollen species richness on pollinators using rarefaction

Abstract

PremiseUnderstanding the flower visitation history of individual pollinators is key in the study of pollination networks, but direct tracking is labor intensive and, more important, does not capture information about the previous interactions of an individual. Therefore, a protocol to detect most of the pollen species on the body surfaces of an individual pollinator could elucidate its flower visitation history.Methods and ResultsUnder a microscope, we observed 6.0‐µL droplets from a sample solution (1.0 or 3.0 mL) containing pollen grains collected from individuals of six major pollinator functional groups. To clarify how many droplets need to be observed to detect all pollen species within the solution, we examined up to 10 droplets collected from each individual insect. Sample‐based rarefaction curve analyses of the data showed that we could detect ~90% of the pollen species and the plant–pollinator links in the networks by observing six droplets.ConclusionsThe rarefaction curve analysis for pollen‐on‐pollinator studies is a useful preliminary step for minimizing the time and labor required while maximizing the data on the flower visitation history of each individual pollinator and revealing any hidden flower–pollinator interactions.

Effects of pesticide treatment against nematode disease on soil bacterial community structure and sweet potato yield and quality

“…It could be used to compare the richness of species in samples with different amounts of sequencing data, and it could also be used to indicate whether the amount of sequencing data in a sample is reasonable. The Rarefaction Curve is constructed by random sampling of sequences and the number of extracted sequences and the number of OTUs that they can represent (Nikkeshi et al., 2021). When the curve tends to be flat, it means that the amount of sequencing data is reasonable, more data will only produce a few new OTUs; otherwise, it means that further sequencing may produce more new OTUs.…”

Diurnal and geographic variations of pollinator importance for Cucurbita maxima Duchesne

“…Briefly, we cut and eliminated hind legs with corbicular pollen loads using scissors and poured 0.4 M of sucrose solution (1.0–6.0 mL, depending on the body size) into each vial with an insect sample. This solution is an isotonic solution for pollen (Nikkeshi, 2022 ) and prevents pollen accumulating at the bottom due to its high viscosity (Nikkeshi, 2022 ; Nikkeshi et al., 2021 ). After shaking it in order to separate pollen from the insect bodies and uniformize it in the solution, we sampled 10 μL of the solution, and counted the number of pollen grains on a microscope slide by microscope.…”