Intraspecific variation in the response to CO enrichment in seeds and seedlings of Plantago lanceolata L.

Four genotypes of P. lanceolata were grown to maturity at combinations of two levels of atmospheric CO concentrations and two temperature conditions. Seed weight was determined, and seed germination and seedling growth were measured for the progeny of each genotype under the same environmental conditions. Overall, high CO levels decreased seed weight, increased germination percentage and rate, and increased seedling size. Families differed in their response to CO enrichment, and to combinations of CO and temperature levels for several characters. These results suggest the existence of genetic variability in P. lanceolata in response to CO enrichment.