Light induced coordinative changes in leaf variegation between mother plants and daughter plantlets of Chlorophytum comosum ‘Vittatum’

More than one third of commercially produced ornamental foliage plants are valued for their variegated leaves. In both shaded greenhouse and shadehouse production of variegated foliage plants that foliar variegation changes with photosynthetically active photon flux densities (PPFDs). Therefore, controlling of appropriate PPFDs in shaded greenhouses or shadehouses is critical to producing variegated foliage plants with the greatest aesthetic appeal. However, only limited information is available on environmental factors influencing foliar variegation. In this study, Chlorophytum comosum ‘Vittatum’ was used as a model to determine if mother plants and daughter plantlets on attached stolons communicated when grown at the same or different PPFDs using leaf variegation as a detection device. Mother plants and attached plantlets were grown under four treatments: (1) both under 304 µmol/m2/s, (2) both under 142 µmol/m2/s, (3) mother plants under 142 µmol/m2 but plantlets under 304 µmol/m2, and (4) mother plants under 304 µmol/m2 but plantlets under 142 µmol/m2. When mother plants were grown under 142 µmol/m2 and daughter plantlets were grown under 304 µmol/m2, foliar light-green color of mother plants increased from 39% to 62%, and yellowish-white decreased from 14% to 2%. The green color of daughter plantlets increased from 38% to 48%, and light green increased from 14% to 47% while yellowish-white color decreased from 48% to 5%. When mother plants were grown under 304 µmol/m2 and daughter plantlets were grown under 142 µmol/m2, green color of the mother plant leaves increased from 35% to 49%, while yellowish-white decreased from 15% to 3%. Green leaf color of daughter plantlets did not change greatly, but light green variegation increased from 55% to 64%, and yellowish-white decreased from 10% to 4%. This study indicated that in addition to water and nutrients obtained by the daughter plantlets from the mother plant through the xylem, mother plants and daughter plantlets communicated via phytochemical signals when their respective canopy light levels changed. Differences in leaf photosynthates may be one trigger that could induce changes in leaf variegation patterns as light levels change.