Seed dimorphism in relation to germination and growth of Cakile edentula

Abstract

Previous studies showed that the two seed morphs produced from the upper and lower fruit segments of Cakile edentula differed significantly in their germinability and carry-over effects on the growth of the subsequent plants. By partitioning variables into seed-morph and seed-mass components, this study suggests that both seed germination and the growth of the subsequent plants depend on seed mass rather than seed morph. Plants from large seeds generally had greater leaf area, shoot to root ratio, biomass, and smaller leaf area ratio than those from small seeds. Within the same seed-mass class, plants from the lower fruit segment showed greater shoot to root ratio only at the end of the experiment. Since specific leaf area, leaf area ratio, and shoot to root ratio depended significantly on plant dry mass, the effect of seed mass on these variables may be actually achieved indirectly through the influence on plant size. Key words: seed dimorphism, seed mass, maternal effect, germination, growth, Cakile edentula.