The influence of interplant distance and number of flowers on seed set in dwarf bear-poppy (Arctomecon humilis)

Abstract

Samples from three isolated populations of the dwarf bear-poppy (Arctomecon humilis Cov.) demonstrate that both flower pollination (fruit set) and seed set per fruit decline as interplant distances increase and the number of flowers per plant declines. Interplant distance and number of flowers per plant tend to interact with reproduction. Seed set per plant is most impaired on plants that produce few flowers and are far from other flowering, conspecific individuals. Such data warn that the number of surviving individuals alone is not a safe criterion for evaluating reproductive health of a plant population. Population density (number of individuals per unit area) strongly influences the reproductive success of this species. Other studies suggest that large reductions in the pollen deposited on stigmas may eliminate competition among pollen grains for access to ovules and adversely affect the vigor of the next sporophyte generation.

Parent Publication

• Southwestern rare and endangered plants: Proceedings of the Third Conference

Citation

Harper, K. T.; Van Buren, Renee; Aanderud, Zachary T. 2001. The influence of interplant distance and number of flowers on seed set in dwarf bear-poppy (Arctomecon humilis). In: Maschinski, Joyce; Holter, Louella, tech. eds. Southwestern rare and endangered plants: Proceedings of the Third Conference; 2000 September 25-28; Flagstaff, AZ. Proceedings RMRS-P-23. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. p. 105-109.