Reproductive barriers and hybridity in two spruces, Picea rubens and Picea mariana, sympatric in eastern North America

Reproductive barriers and hybridity in two spruces, Picea rubens and Picea mariana, sympatric in eastern North America

Hybridization between red spruce (Picea rubens Sarg.) and black spruce (Picea mariana (Mill.) BSP), lateand early-successional species, respectively, has resulted in identification and management problems. We investigated the nature and magnitude of reproductive and life-cycle success barriers in controlled intraand inter-specific crosses of red and black spruce. We quantified a number of repro...

Negative heterosis not apparent in 22-year-old hybrids of Picea mariana and Picea rubens

Work from the 1970s indicated that, relative to either parent species, crosses between red spruce (Picea rubens Sarg.) and black spruce (Picea mariana (Mill.) B.S.P.) were inferior with respect to both growth and photosynthesis. We re-examined the hypothesis that there is negative heterosis in hybrids of red and black spruce using 22-year-old trees in a common garden study planted on two sites....

Genetic variation and control of chloroplast pigment content in Picea rubens, Picea mariana, and their hybrids, under ambient and elevated CO2 environments

Genetic variation and control of chloroplast pigment concentrations in Picea rubens, Picea mariana and their hybrids. I. Ambient and elevated [CO2] environments.

Traits related to light-energy processing have significant ecological implications for plant fitness. We studied the effects of elevated atmospheric CO(2) concentration ([CO(2)]) on chloroplast pigment traits of a red spruce (RS) (Picea rubens Sarg.)-black spruce (BS) (P. mariana (Mill.) B.S.P.) genetic complex in two experiments: (1) a comparative species' provenance experiment from across the...

A late-glacial transition from Picea glauca to Picea mariana in southern New England

Picea is an important taxon in late-glacial pollen records from eastern North America, but little is known about which species of Picea were present. We apply a recently developed palynological method for discriminating the three Picea species in eastern North America to three records from New England. Picea glauca was dominant at ∼14,500–14,000 cal yr BP, followed by a transition to Picea mari...