Coordination of leaf economics traits within the family of the world’s fastest growing plants (Lemnaceae)

The duckweed family (Lemnaceae) is a group of free-floating aquatic plants with bodies consisting of single floating fronds that multiply clonally. Although they are known to have the fastest relative growth rate (RGR) among higher plants, their functional trait coordination in relation to within-family variation of RGR is poorly understood. We tested how duckweed species fit within the trait covariation patterns known as the worldwide leaf economics spectrum (LES). To this end, several functional traits were evaluated for 15 duckweed species, and their covariation patterns were compared with those in the global database of plant functional traits. As a group, duckweeds exhibited the most acquisitive suite of traits, with extremely small leaf mass per area (LMA), short lifespan, and high mass-based photosynthetic rate (Amass). These LES traits showed a tight correlation with RGR, corroborating our hypothesis that acquisitive leaf resource economics underpins their extremely high R...