Kwak et al. 1985
From Offene Naturführer
Kwak, M. M., Holthuijzen, Y. A. & Prins, H. H. T. 1985: A Comparison of Nectar Characteristics of the Bumblebee-Pollinated Rhinanthus minor and R. serotinus. In: Oikos. Bd. 44, Nr. 1, , S. 123; 123–126, doi:10.2307/3544052 (https://www.jstor.org/stable/3544052, abgerufen am 19. Mai 2020). (Übersetzung: Ein Vergleich der Nektareigenschaften der Hummel-bestäubten Rhinanthus minor und R. serotinus)
Zusammenfassung: The nectar characteristics (amount, concentration and sugar ratios) of two sympatrically occurring and synchronously flowering Rhinanthus species were investigated. Data were collected on days with different temperatures. Nectar amounts available for bumblebees (pollinators) were higher on a hot day in Rhinanthus serotinus than in R. minor. On a cool day no differences were found except in the early morning. Nectar of R. serotinus taken at any one time showed higher sugar concentrations than R. minor. Nectar of both species contained fructose, glucose and sucrose. In R. minor lactose and rhamnose were also detected. The relationship of these findings to previously demonstrated floral preference of bumblebees is discussed.