Glossary
Forest Genetics and Tree Improvement
Adaptation:
A change on the part of an individual or population in respect of
their environments resulting in better survival, growth or reproduction.
This may occur by natural selection, as individuals with favourable
genetic traits breed more prolifically than those lacking these traits,
or it may involve non-genetic changes such as physiological modification
in response to the environment.
Adapted
material: Material resulting from natural evolution, or breeding
and testing, that is capable of adequate growth and reproduction in
a given habitat and that will not have adverse impacts on the health,
functioning and productivity of the ecosystem.
Afforestation:
The establishment of a forest or stand of trees in an area where the
preceding vegetation or land use was not forest.
Allele:
An alternate form of a gene, differing in DNA sequence and affecting
the functioning of a single gene product (RNA and/or protein).
Base
population: The population of trees from which individuals
are chosen to establish the breeding population for a tree improvement
program. Generally refers to a wild population within a breeding region.
Biodiversity:
The variety and variability among living organisms and the ecosystems
of which they are part. Biodiversity has three levels or components
– ecosystem diversity, species diversity and genetic diversity.
Biogeography:
The study of the distribution of organisms over the earth and of the
principles that govern their distribution.
Breeding:
The science and art of changing the genetic constitution of a population
of plants or animals.
Breeding
population: A set of trees within which crosses are made
to generate material for the next cycle of selection
Breeding
region: A geographic area, defined mainly by adaptation criteria,
for which improved materials are selected, bred, tested, multiplied
and deployed in reforestation.
Breeding value: The genetic
value of an individual for a given trait, based on the mean performance
of its offspring or other relatives determined through field or laboratory
testing.
Clinal or Clinal Variation: A continuous character
gradient, usually assumed to be genetically controlled, linked with
geography and environment. Adjacent populations merge into one another
with regard to character expression with no sharp breaks.
Clone:
An individual or group of individuals reproduced asexually from a
single organism, and therefore genetically identical to the parent.
Collections,
public land: Genetic material gathered and removed from public
land for the purposes of reforestation, breeding or research
Community:
A group of ecologically related populations of various species that
occur in a particular geographic area at a particular time.
Controlled
parentage program: A stock production program that includes
in its population a number of selected individuals. Production of
deployment stock for the program occurs in a production facility (such
as a seed orchard or stoolbed) where parents are propagated vegetatively
or sexually.
Deployment:
Establishment of a new forest through artificial regeneration - planting
or seeding designed to meet resource management objectives or obligations.
Afforestation, reclamation and reforestation are examples of deployment.
Deployment
zone: A geographic area, defined mainly by adaptation criteria,
for which tree improvement materials are produced. Deployment zones
include breeding regions.
Dioecious:
A tree species having female and male sex organs on different plants.
Ecosystem:
A complex interacting system that includes all plants, animals, and
their environment within a particular area.
Effective
Population Size: The average number of individuals in a population
that contribute genes to the succeeding generations.
Ecotype
or Ecotypic Variation: A genetically differentiated population
distinguished from adjacent populations by sharp discontinuities in
character expression. Ecotypic variation is a result of adaptive selection.
Ecotypes may be geographic, climatic, elevational, or edaphic.
Embryo:
That portion of the seed resulting from union of male and female gametes
and developing into a mature plant.
Endangered:
A term that applies to taxa (population, subspecies, species) in danger
of extinction and for which survival is unlikely if the causal factors
of loss continue.
Endemic:
Species or population(s) native to a small region and found nowhere
else.
Ex
Situ: A method of conservation in which components of biodiversity
are conserved outside of the site, away from the natural habitat.
Exotic:
An introduced species or population not native to Alberta.
Fitness:
The relative ability of organisms of a particular genotype to survive
and produce offspring, or the contribution of one of a pair of alleles
to the general vigour of an organism.
Gamete:
A male or female reproductive cell capable of uniting in the process
of fertilization with one of the opposite sex to develop into an embryo.
Gene
Flow: The movement of genes (i.e alleles) within a population
or between interbreeding populations as a result of outcrossing and
natural selection or seed migration.
Gene
Pool: The totality of genes and their alleles within an interbreeding
population.
Genecology:
The study of the genetics of the populations of plants in relation
to the ecological niches they occupy; the study of adaptive properties
of the populations in relation to their environments.
Genetic
diversity: In a group such as a population or species, the
possession of a variety of genetic traits that frequently result in
differing expressions in different individuals. The variation of genes
within a species, the material upon which the agents of evolution
act. Loss of variation may prevent adaptive change in populations
of a species and reduce its ecological fitness
Genetic
Drift: Change in gene frequencies from generation to generation
due to sampling errors that operate when an offspring generation is
formed by random union of gametes in a finite population.
Genetic
gain: The average heritable change attributable to selection
in a given trait, from one generation to the next.
Genetically
modified organism (GMO): An organism that, through human
intervention in a laboratory, has had its genome, or genetic code,
deliberately altered through the insertion of a specific identified
sequence of genetic coding material (generally DNA) that has been
either manufactured or physically excised from the genome of another
organism. Genetic modification may be used to alter any of a wide
range of traits, including insect and disease resistance, herbicide
tolerance, tissue composition and growth rate.
Genetic
Variation: Differences displayed by individuals within a
species which may be favoured or eliminated by natural or artificial
selection. In sexual reproduction, reshuffling of genes through recombination
in each generation ensures the maintenance of variation. The ultimate
source of variation is mutation which produces fresh genetic material.
Geographic
Variation: Variation among individuals and populations found
in a tree species natural geographic range. The amount and nature
of variation may vary with the species, the extent of its geographic
distribution and ecological and climatic diversity of habitats that
it occupies in its natural range. A large part of this variation may
be genetic and may be further divided into clinal, ecotypic and unexplained
classes.
Genotype:
The genetic composition of an individual or group that may be either
expressed or unexpressed, depending upon environmental effects of
a given location.
Germplasm
collection: A collection of many different varieties, species,
or subspecies representing a diverse collection of genotypes and,
hence, genetic diversity.
Green
Area: The Green Area in Alberta consists of public land that
is primarily forested, and is managed for timber production, oil/gas
development, watershed, wildlife and fisheries, recreation and other
uses.
Habitat:
The natural environment in which an organism or population lives.
Habitat may refer to all of the organisms and their physical environment
in a particular place.
Heritability:
An attribute of a quantitative trait in a population that expresses
how much of the total phenotypic variation is due to genetic variation.
Heterozygosity:
The condition of having one or more pairs of dissimilar alleles.
Hybridization:
The processes of cross-mating individuals or populations
that possess different genetic makeups.
In
Situ: A method of gene conservation where genetic resources
are conserved on site, within the natural habitat.
Inbreeding:
The intentional or unintentional breeding or crossing of individuals
that are more closely related than their parents.
Intellectual
property rights: The rights to intangible property that is
the product of the human intellect. Intellectual property may be protected
by copyright, trademark or patent. The holder of intellectual property
rights is usually the person or persons who developed the product
or the organization that funded it.
Introgression
or Introgressive Hybridization: The incorporation of genes
of one species into the gene pool of another. If the ranges of the
two species overlap and fertile hybrids are produced, they tend to
backcross with the more abundant species. This process results in
a population of individuals most of whom resemble the more abundant
parents but who possess also some characters of the other parent species.
Minimum
Viable Population: The size below which a population can
not remain stable or increase in number, but will decline and disappear,
due either to insufficient reproduction or the genetic consequences
of inbreeding.
Monoecious:
A tree species having female and male sexual organs on the same plant.
Mutation:
The process by which a gene undergoes a structural change; a modified
gene resulting from mutation.
Natural
range: Range of natural distribution of a taxon, excluding
any portion that is the result of introduction to a region.
Natural
Region: A geographic area in Alberta delineated as part of
an ecological site classification and possessing a distinctive combination
of physical features (climate, geology, soils, hydrology) and biological
features (plant and animal species, vegetation communities). Alberta
is subdivided into six Natural Regions which are: Canadian Shield
Natural Region, Boreal Forest Natural Region, Rocky Mountain Natural
Region, Foothills Natural Region, Grassland Natural Region and Parkland
Natural Region)
Natural
Selection: The process by which the genetic makeup of a population
changes under natural conditions, without human interference, on the
basis of its ability to become better adapted, survive or reproduce
in a particular set of environmental conditions.
Natural
Subregion: A subdivision of Natural Region based on biogeoclimatic
factors. The six Natural Regions in Alberta are divided into 20 Natural
Subregions.
Pedigree:
A record of parentage, sometimes also including data on the performance
of parents and other relatives.
Phenology:
The study of timing of periodic phenomena such as flowering, growth
initiation, growth cessation, etc. especially as related to seasonal
changes in temperature, photoperiod, etc.
Phenotype:
The sum total of the environmental and genetic (hereditary) influences
on a tree; the visible characteristics of a plant.
Propagule:
A live entity capable of producing a new mature individual (e.g.,
a cutting, graft, tissue culture explant)
Population:
A group of individuals of the same species that occupy a particular
geographic area or region. In general, individuals within a population
interbreed and exchange genes with each other.
Provenance:
The original geographic source of seed or other propagules. Also,
the test population resulting from seed collected from a particular
location.
Public
land: Alberta “public lands” as defined in the
Public Lands Act. Includes Green Area (land managed primarily as forest
land) and White Area (land managed primarily for agriculture and uses
other than forestry).
Ramet:
An individual that has been vegetatively reproduced from the original
plant, or ortet, and is thus genetically identical to it.
Rare:
A tree species with limited natural distribution in Alberta and which
is characterized by small population sizes and/or numbers.
Reclamation:
A planned series of activities designed to recreate the biophysical
capacity of an ecosystem
Reforestation:
The reestablishment of trees on denuded forest land by natural or
artificial means such as planting and seeding.
Registration:
The process that allows a seed or vegetative lot to be used for deployment
within its deployment zone or seed zone on public land.
Seed
orchard: A stand of trees, usually several hundred to several
thousand in number, established and managed primarily for early and
abundant production of seed for deployment. Trees in the orchard are
derived and propagated from selected parent trees by grafting or by
seed.
Seed
zone: A geographic area, defined on the basis of ecological
characteristics and genetic information, within which seeds may be
collected and freely deployed without any significant loss of adaptation
and growth potential. Alberta (excluding National Parks) is divided
into 84 seed zones of which 74 are in the Green Zone area. Seed Zones
are subdivisions of natural subregions.
Stoolbed:
An aggregation of closely spaced stumps, or stools, managed for the
production of one-year-old vegetative sprouts (whips). Harvested whips
are used for operational planting stock and can be pre-rooted prior
to deployment.
Test
or Field Trial: A research planting established in a scientific
design to develop knowledge or information on the performance of genetic
materials (species, provenances, seed sources or progeny) on traits
or attributes (survival, growth, pest susceptibility, frost hardiness,
wood quality, etc.) of interest.
Threatened:
The term refers to taxa for which the potential for loss exists but
for which there is insufficient data to determine whether they are
endangered.
Taxon
(plural taxa): The general term for a taxonomic group, no
matter its rank.
Taxonomy:
The study of classification of living things. Classically taxonomy
is concerned with description, naming, and classification on the basis
of morphology. More recently taxonomists have been concerned with
the analyses of patterns of variation in order to discover how they
evolved and with the determination by experiment of the genetic interrelationships
between them.
Viable
Population: A population, which maintains its genetic diversity,
maintains its potential for evolutionary adaptation and is at minimal
risk of extinction from demographic fluctuations, environmental variations
and potential catastrophe, including over-use.
White
Area: Private and public land in the settled portion of the
province, managed primarily for agriculture use, but not excluding
other uses such as timber, oil/gas development, recreation, soil and
water conservation, and fish and wildlife habitat.
Wild
population: A population within its natural range in which
the individuals are the result of natural reproduction.
References
Allaby, M. 1994. The Concise Oxford Dictionary of Ecology. Oxford
University Press, New York.
Canadian
Council of Forest Ministers. 2003. Defining Sustainable Forest Management
in Canada – Criteria and Indicators.
Cote,
M. (ed.). 2000. Dictionnaire de la foresterie. Dictionary of Forestry.
Les Presses de l’Universite Laval, Laval, Quebec..
Gardenfors,
U., C. Hilton-Taylor, G.M. Mace, and J.P.Rodriguez. 2001. The application
of IUCN red list criteria at regional levels. Conservation Biology
15:1206-1212.
IUCN.
1993. The convention on biological diversity: an explanatory guide,
draft text, IUCN Environmental Law Centre, Bonn, Germany.
King,
R.C. and W.D. Stansfield. 1990. A Dictionary of Genetics. Oxford University
Press. New York
Maynard,
C. 1996. Glossary of forest genetics. Unpublished.
National
Research Council. 1991. Managing Global Genetic Resources –Forest
Trees. National Academy Press, Washington, D.C.
Richardson,
D.M. (Ed.). 1998. Ecology and Biogeography of Pinus. Cambridge University
Press, Cambridge.
Wright,
J.W. 1976. Introduction to Forest Genetics. Academic Press, New York