James W. Hanover

Applications of terpene analysis in forest genetics

Terpenoid substances in forest trees are versatile biochemical systems for use as genetic markers and for studying genetic regulation at the biochemical level. Univariate, multivariate and correlative data analyses from numerous studies on different coniferous species are presented. These data indicate that fitness values for most terpenes examined are probably so low as to be unmeasurable except in long evolutionary time spans. Variation patterns for monoterpenes often closely parallel racial differentiation for morphological traits and reflect the migratory history of species and species-complexes. Random drift and gene flow are likely the major influences on genetic organization of terpene variability. Mutation in regulatory genes may be responsible for quantitative variation within major gene systems for terpenes. The mono-, sesqui- and diterpene systems in conifers offer good opportunities for research on the nature of gene regulation in plants and its evolutionary significance.

Agroforestry systems for the temperate zone

Historical development of a permanent agriculture system based on the use of agroforestry in the temperate zone is traced. In general, reasons for a renewed interest in agroforestry include the end of cheap, subsidized fossil fuels; increased concern about soil erosion and marginal land use; an international awakening as to the dangers of indiscriminate use of pesticides, herbicides and other chemicals; and a need to balance food production with other land uses.For the forestry profession in particular, reasons for interest in agroforestry stem from a need to revitalize rural economies, the desire to increase timber exports, and potential resolution to land use conflicts between agriculture and forestry. Through use of agroforestry management systems, an increase in both economic and silvicultural benefits are obtainable.Two agroforestry management systems are reviewed which currently appear feasible for implementation in many industrialized countries of the temperate zone. These two systems include: 1) Animal grazing and intercropping under managed coniferous forests or plantations; and 2) Multicropping of agricultural crops under intensively managed, high value hardwood plantations.

Comparison of techniques for extracting volatile compounds from conifer needles

Five extraction techniques were used to obtain quantitative measurements of monoterpenes from blue spruce and grand fir needles. Multivariate analysis of variance indicated that there was a significant difference in the amount of each monoterpene extracted by using different techniques. For both species, an 8-hr steam distillation of 10 g of material yielded the greatest amount of each monoterpene. This technique was also the most reproducible in that the coefficients of variation were lowest. A rapid steam distillation was relatively effective for grand fir, but not for blue spruce. A CO2 extraction was unreliable for both species.

Genetics of terpenes II. Genetic variances and interrelationships of monoterpene concentrations in Pinus monticola

Genetics of terpenes II. Genetic variances and interrelationships of monoterpene concentrations in Pinus monticola

HONEYLOCUST (GLEDITSIA TRIACANTHOS), A MULTI-PURPOSE TREE FOR THE TEMPERATE ZONE

SUMMARY Honeylocust, Gleditsia triacanthos L., is a multipurpose tree with economic potential in temperate zone agroforestry management systems. A review of past research and results from an ongoing tree improvement research program and development of a silvopastoral ideotype are discussed. Constraints to realization of its full potential include: the lack of field tested systems; the need to develop mechanical harvesting procedures; a requirement for careful genotype/site matching; a lack of proven, consistent, heavy bearing varieties; thorniness; and variation in winter hardiness.

Inter-Tree Variation of Essential Oil Composition of Thuja occidentalis L.

ABSTRACT Variation in the composition and yield of the essential oils of Michigan grown northern white cedar (Thuja occidentalis L.) is reported. Comparison of oil isolated from the foliage of individual trees revealed significant inter-tree variation in oil composition. The optimal pilot scale distillation time was found to be about 40 minutes. Total oil yield using steam distillation is almost identical among the ten trees analyzed, but ketone content and diterpene percentages vary significantly from tree to tree. Ketone content of T. occidentalis can be used as criteria for tree selection since its percentage varies widely from 58 to 77%. Diterpene content may also prove useful as markers but more work is needed to help quantify the genetic and environmental components of phenotypic variation.

Contribution to the Study of the Essential Oil of Thuja occidentalis L.: In memory of Dr. James W. Hanover who died February 21, 1992

ABSTRACT A combination of GC and MS was used to identify 40 different compounds in the essential oil of Thuja occidentalis L. foliage samples collected from mid-Michigan (USA). The essential oils were obtained by three different methods: pilot scale steam distillation, cool hexane solvent extraction, and laboratory steam microdistillation. By all three methods the major compounds identified were α-thujone (39–56%), fenchone (6.0–15.0%), β-thujone (7.2–11.0%), sabinene (2.1–8.9%), beyerene (1.30–5.95%), bornyl acetate (1.20–4.38%) and camphor (1.5–3.3%). Fifteen diterpenes were found, eight of which were identified for the first time in the oil of T. occidentalis foliage. Variations in the oil composition as a function of isolation technique are also reported.

Geographic variation in the essential oil monoterpenes of Liriodendron tulipifera L

The monoterpene component of Liriodendron tulipifera L. (Magnoliaceae) essential oils was quantitatively analysed in branch samples collected from an Ohio provenance test of 11 geographic seed sources representing the natural range of the species. Mean monoterpene composition of the essential oil is described and significant differences in the monoterpene composition among geographic sources are discussed.