Handedness of spathes and leaves of alocasia brisbanensis (Araceae), mainly in Queensland

Abstract

The numbers of left-and right-handed spathes of Alocasia brisbanensis (totalling 2,613 of which 92.3% were from Queensland) examined during nine seasons, were not significantly different from a 1:1 ratio. In addition, 48 individual spathes exhibited both left-and right-hand folding. The numbers of left-and right-folded leaves of 103 flowering plants were also not significantly different from a 1:1 ratio, but those of 20 non-flowering plants were significantly different (P <0.01), the reason for which is unexplained. Occasional reversals and re-reversals of direction occurred in left-and right-hand sequences in both spathes and leaves. The mechanism underlying 1:1 handedness, reversals, re-reversals and mixed individual spathes of this species, and of this phenomenon in other plants, needs to be investigated.