Photosynthetic adaptation ofSolanum dulcamara L. to sun and shade environments. III. Characterization of genotypes with differing photosynthetic performance.

Clone mal9, a genotype ofSolanum dulcamara L. having photosynthetic characteristics similar to previously hypothesized shade ecotypes, is compared to five other genotypes having photosynthetic characteristics similar to previously hypothesized sun ecotypes. The primary differences are a 35% reduction in total leaf conductance and a 15% reduction in leaf chlorophyll content in mal9. Both factors contribute to a 44% reduction in lightsaturated photosynthetic rate in mal9. In relation to the 5 other genotypes, mal9 appears to be poorly adapted for growth in the normal range of natural habitats.