A marriage of convenience; a simple food chain comprised of Lemna minor (L.) and Gammarus pulex (L.) to study the dietary transfer of zinc

Abstract

Macrophytes contribute significantly to the cycling of metals in aquatic systems, through accumulation during growth and release during herbivory or decomposition. Accumulation of high levels of metals has been extensively documented in Lemnaceae (duckweeds). However, the degree of trophic transfer of metals from Lemnaceae to secondary consumers remains poorly understood. This study demonstrates that zinc accumulated in Lemna minor is bioavailable to the herbivore consumer Gammarus pulex. Overall, the higher the zinc content of L. minor, the more zinc accumulated in G. pulex. Accumulation in G. pulex was such that mortality occurred when they were fed high zinc-containing L. minor. Yet, the percentage of consumed zinc retained by G. pulex actually decreased with higher zinc concentrations in L. minor. We hypothesise that this decrease reflects internal zinc metabolism, including a shift from soluble to covalently bound zinc in high zinc-containing L. minor. Consistently, relatively more zinc is lost through depuration when G. pulex is fed L. minor with high zinc content. The developed Lemna-Gammarus system is simple, easily manipulated, and sensitive enough for changes in plant zinc metabolism to be reflected in metal accumulation by the herbivore, and therefore suitable to study ecologically relevant metal cycling in aquatic ecosystems.

Do particle size and surface functionality affect uptake and depuration of gold nanoparticles by aquatic invertebrates?

“…In the case of fish, NPs could be taken up through the gill or skin by absorption, but the dietary intake route is likely a major route for aggregated or larger sized NPs . Gammarus pulex feed mainly through shredding , but uptake from water is probably an additional important route .…”

After the genome sequencing of duckweed – how to proceed with research on the fastest growing angiosperm?

“…Horemans et al (2015) report the different effects of uranium and cadmium on oxidative stress response in Lemna minor, while Monselise et al (2015) demonstrated, using NMR measurements, the presence of alanine as a universal stress marker, here after UV irradiation of Landoltia punctata (formerly Spirodela oligorrhiza). The transfer of zinc into the food chain was investigated by the group of M. A. K. Jansen (Lahive et al 2015) using the interaction partners L. minor and Gammarus pulex (L.). Kuehdorf et al (2014) showed the different capacity of clones of Spirodela polyrhiza to form dormant organs (turions) as an adaptation to climate conditions at the place of collection.…”

Interactions of Coated-Gold Engineered Nanoparticles with Aquatic Higher Plant Salvinia minima Baker

“…This, in turn, has led to their concomitant interactions with aquatic organisms including aquatic higher plants-a primary producer and food source to organisms, e.g., crustaceans [73]. As a result, aquatic higher plants not only can act as reservoirs of NPs [20,61] but a source of NPs for subsequent transfer to higher trophic levels [8,73]. Herein, results demonstrate an insignificant effect of nAu on biomass and growth rate over time.…”

“…Increasing production and widespread use of nAu have led to their release and accumulation in the environment [7,16]. This, in turn, has led to their concomitant interactions with aquatic organisms including aquatic higher plants-a primary producer and food source to organisms, e.g., crustaceans [73]. As a result, aquatic higher plants not only can act as reservoirs of NPs [20,61] but a source of NPs for subsequent transfer to higher trophic levels [8,73].…”