SFI 30 (LEC) 3

Seed Source

Individual

trees or stands, natural or

planted, from which seed is

collected.

Seed trees

Trees from

which seed is collected.

Genotype

Genetic constituents of an

individual tree which, in

interaction with the

environment, largely controls

tree performance and is

inheritable by its progeny

Phenotype

The observed

characteristics of a tree, which result

from the interaction of the genotype

and environment.

Plus trees(selected trees)

Superior phenotypic trees from

seed is collected or Individual trees selected for their

phenotypic superiority within a

plantation

Physical Quality
Physiological Quality
Genetic quality

Three Components of Seed Quality

Physical Quality

Quality related to physical characteristics,

such as size, color, age, seed coat conditions, occurrence of

cracks, pest and disease attacks, or other damage.

Physiological Quality

Quality related to physiological

characteristics, such as maturity, moisture content, or

germination ability.

Genetic Quality

Quality related to characteristics inherited

from the parent trees.

seed sources

Importance of seed quality in

plantation success

Establishment of quality seed

sources is the heart of any

seed certification program.

Quality seeds

genetically

superior stands

(natural/artificial) (seed sources)

controlled general collection
uncontrolled general collection

2 Broad Classification of Seed Sources

Unknown sources
No selection or supervisions
Seeds = unclassified

Uncontrolled general collection

Properly identified sources
limited/no tree selection
supervised
seeds tested for quality
Seeds = source identified

Controlled general collection

Seed Production area (SPAs)

Genetically upgraded plus stands

Removal of undesirable trees +

cultural treatments (e.g.,

thinning)

At least 20 unrelated families to

minimize inbreeding

Select seeds

what do we call the seeds of SPAs

Seed Orchards

• Mass production of seeds for

maximum genetic gain

• Selected clones or progenies

• Isolated/managed to avoid

contamination or pollination from

outside sources

certified seeds

what do we call the seeds for seed orchards

Homogeneous site
Heterogeneous site

site for seed tree selection

Homogeneous site

appropriate for seed tree selection

heterogeneous site

Inappropriate for seed tree selection

Selection of superior phenotypic seed tree

inbreeding depression growth

Poor survival, growth and form resulting from _____________ of normally outcrossing species, such as most forest tree species

Straightness
height
Diameter
Crown form
health
vigor

Site and Tree Selection criteria

Good growth conditions
accessibility
low contamination risk

Site and Tree Selection site

Unclassified (seed tree)
Source Identified (Seed stand)
Select Seeds (SPAs)
Certified Seeds (seed orchards)

Seed quality hierarchy