Methanolic extracts of the dormant Douglas-fir shoots (buds, leaves, and stems) were fractionated by solvent partitioning (sodium bicarbonate-diethyl ether). The acidic portion of the extract was subjected to column (Sephadex LH-2O, Silica Gel and Polyvinylpyrrolidone), preparative thick-layer and gas-liquid chromatography.
Fractions collected from chromatographic separations were collected and tested for...
Definitive evidence for the occurrence and seasonal variation of indole-3 -acetic acid (IAA) in shoots 0 DougLas-fir (Pseudotsuga rrienztesii (Mirb. ) Franco) was sought. Collections obtained in December and June were extracted by solvent using methanol arid diethyl ether arid by certtrtfugatiori. Extraction by ceritrifugation appeared to be twice as...
Vegetative propagation is most effective when individuals of demonstrated superior characteristic can be propagated. For this
reason, a method for the induction of adventitious buds on cultured Douglas-fir shoot tips from 20-25 year old trees was developed. Douglas-fir shoot tips failed to survive and grow on a full strength Murashige...
The goal of this thesis was to determine the physiological mechanisms that link adverse preplanting treatments of Douglas-fir, such as exposure and root pruning, to the phenomenon of transplanting shock. The objective of experiments 1 and 2 was to measure the effect of exposure and pruning on the physiology and...
Tap-root wounds frequently occur on seedlings during lifting in
forest tree nurseries. Data are needed to clarify guidelines for
culling wounded seedlings. Two-year-old bareroot Douglas-fir
(Pseudotsuga menziesii (Mirb.) Franco) seedlings were wounded by hand on
the tap-root to lengths of either 3/8, 1, or 3 inches. Wounded
seedlings were used...
Three experiments were conducted on containerized seedlings to examine the short-term and long-term effects of environment on the root regeneration potential, and to examine the fate of the current photosynthate and its relationship to the root regeneration potential. The short-term effects were studied first in a 3x3x2 factorial experiment comprising...
The physiological condition of tree seedlings at the time they are planted can have a profound impact on their subsequent field performance. Damaged or low vigor seedlings have a much greater chance of dying in the field, or at best, of growing slowly during their initial establishment period. Several methods...
The goal of this study was to evaluate the ability of two seedling quality evaluation methods to predict the field survival of Douglas-fir (Pseudotsuga menziesii) seedlings. The starch reserves in seedlings have been suggested as a possible predictor of seedling quality. Starch reserves have been shown to decrease during cold...
The relationships among total water potential (psi), osmotic potential ([pi]), pressure potential (P), and relative water content (R*) were determined during four consecutive soil drying cycles for shoots of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) seedlings. In each cycle, seedlings were sampled for pressure-volume determinations as soil water was depleted gradually...
The physiological condition of a seedling often determines its ability to survive when planted. However, physiological damage is difficult to determine from external measurement or observation, because a healthy looking seedling can be of poor quality (quality is defined as the ability of a seedling to survive when outplanted). Methods...