Genealogical relationship among members of selection and production populations of yellow cedar (Callitropsis nootkatensis [D. Don] Oerst.) in the absence of parental information.

We used DNA fingerprinting and pedigree reconstruction to determine the genetic relationship among members of 3 yellow-cedar (Callitropsis nootkatensis [D. Don] Oerst.) selection populations in the absence of their parental genotypes. Selection population members consisted of the tallest individuals within seedling crops originated from natural stand seed collected from multiple seed donors covering wide areas within 3 distinct locations (phenotypic mass selection). Pairwise relative kinship estimates indicated the presence of extensive coancestry among the selected seedlings, and pedigree reconstruction grouped each selection members into multiple full-sib families of different sizes (1-10) nested within several half-sib families (19-21). The "STRUCTURE" program (Pritchard JK, Stephens M, Donnelly P. 2000. "Inference of population structure using multilocus genotype data." Genetics. 155:945-959.) provided a pictorial classification of the 3 selection populations and grouped their individuals into multiple cohorts (9-10). The STRUCTURE program's results corresponded with that of the pedigree reconstruction, indicating that members of the selection populations originated from a subset of the seed donors forming the natural stand seed collections. The species' silvics, reproductive biology, methods of natural stand seed collection and seedling production, and the high selection intensity applied to form the selection populations contributed to limiting the selection to a subset of the original donor trees. The associated buildup of coancestry in selection and production populations is expected to result in inaccurate estimation of genetic parameters and an unintentional reduction in genetic diversity in reforestation stocks.

Dynamic changes in concentrations of auxin, cytokinin, ABA and selected metabolites in multiple genotypes of Douglas-fir (Pseudotsuga menziesii) during a growing season.

Changes in concentrations of several endogenous phytohormones and metabolites were analyzed in the long shoots of nine genotypes of coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) at five developmental stages: (1) closed buds, (2) flushing buds, (3) rapidly elongating shoots, (4) growing shoots and (5) near full-length shoots during one growing season. When averaged across genotypes, indole-3-acetic acid (IAA) concentration was high at stages 1 and 3. The only pattern that correlated with cone productivity was the one that was unique to IAA, in which high concentrations at stages 3 and 4 were found in all genotypes with high female cone productivity. Concentrations of isopentenyl adenosine (iPA) decreased and zeatin riboside (ZR) concentrations increased as the buds initiated and differentiated; ZR was 30 and 28 ng g(-1) dry weight (DW) at stages 1 and 4, respectively, before increasing to 166 ng g(-1) DW at stage 5. Isopentenyl adenosine peaked at 92 ng g(-1) DW at stage 2 and declined to low concentrations at stages 4 and 5. Zeatin-O-glucoside was 30 ng g(-1) DW at stage 1, declined at stages 2 and 3 and increased at stages 4 and 5. High abscisic acid (ABA) concentrations were positively correlated with rapid shoot elongation (stages 1 and 2), but as growth slowed and terminated, ABA concentrations decreased. Abscisic acid was 7 microg g(-1) DW at stage 1, increased to 13 microg g(-1) DW at stage 2 and then declined. The glucosyl ester (GE) of ABA decreased rapidly in early summer, and increased inversely with an increase in ABA. Between stages 1 and 2, ABA-GE decreased from 10 to 0.2 microg g(-1) DW and then increased. Of the ABA catabolites studied, 7'-hydroxy-ABA was about 2 microg g(-1) DW at stage 1, declined at stages 2 and 3 and increased at stages 4 and 5; phaseic acid concentrations were low at all stages, whereas dihydrophaseic acid was detected only at stages 4 and 5.