Juvenile cutting production techniques and early field-performance of cutting versus seedlings of slash pine (Pinus elliottii Englm.)

Typescript (photocopy).This dissertation presents results of two separate studies. The first study evaluated chemical and manual pruning techniques for inducing fascicular bud and shoot development of nine-month-old slash pine; subsequent rooting performance was evaluated for the best pruning techniques. The chemical and manual pruning study was separated into two experiments. The first experiment indicated that decapitation, decapitation + benzylamino purine (BAP) and morphactin treatments induced greater percentages of buds and shoots. The second experiment evaluated techniques which induced lateral shoots suitable for rooting evaluation. Decapitation and decapitation + BAP treatments were imposed over seedlings from the first experiment. Seedlings receiving only decapitation treatment produced longer shoots, and a larger number of shoots suitable for rooting than the decapitation + BAP treatment; percent rooting differences were non-significant. Decapitation + BAP treatment induced more shoots less than 8 cm in length. The second study compared first-year field results of morphological traits and genetic parameters of seedlings and rooted cuttings from genetically related populations. Seedlings were larger for height and diameter than the rooted cuttings after the first growing season. These differences were related to initial size advantage of seedlings at the time of planting. The rooted cutting population however had a larger relative height growth than the seedling population. Crown traits, stem form and survival were not significantly different for both propagule types.Intraclass correlations of growth and crown traits ranged from 0.48 - 0.03 for clones and 0.065 - 0.006 for seedlings. Phenotypic correlations for relative height growth with diameter, stem, and crown traits were significant, positive, and larger for seedlings than the cuttings. Correlations between diameter, stem and crown traits were similar for both propagule types. Clonal coefficients of genetic prediction for all traits except initial versus first-year height (0.350) were low, ranging from 0.138 - 0.001. Genotype x environment interactions were detected only for the clonal analyses of first-year height and survival