Differential effects of transgenerational plasticity on morphological and photosynthetic properties between an invasive plant and its congeneric native one

Phenotype of plant offspring may be affected by particularly maternal environmental conditions, which is named as transgenerational plasticity. Transgenerational plasticity enhances the fitness of offspring under the maternal environmental conditions. Transgenerational plasticity may promote the successful invasion of alien plants, particularly those with clonal growth. However, few studies have compared transgenerational plasticity between alien invasive clonal plants and their congeneric native ones. A pot experiment with the invasive herb Wedelia trilobata and its congeneric native species Wedelia chinensis was conducted to investigate effects of light conditions (low vs. high light treatment) experienced by mother ramets on morphological and photosynthetic properties of offspring ramets subjected to the low light treatment. Compared with those of offspring ramets from mother ramets subjected to the high light treatment, leaf area, potential maximum net photosynthetic rate ( P max ) and biomass accumulation of offspring ramets from mother ramets subjected to the low light treatment were significantly greater in W. trilobata than W. chinensis . Opposite pattern was observed in number of offspring ramets. We conclude that effects of transgenerational plasticity on growth performance could be species-specific between invasive plant and its congeneric native one. Positive effect of transgenerational plasticity on number of offspring ramets was not transformed into growth advantages of native species W. chinensis during its later establishment. However, favorable effects of transgenerational plasticity on capturing light resource could enhance competitive ability and promote successful invasion of W. trilobata .