Báo cáo nghiên cứu nông nghiệp " Isolation, inbreeding and relationships in forest trees " pdf

Forestry and Forest Products
Selection concepts
Isolation, inbreeding and
relationships in forest trees
Forestry and Forest Products
Isolation, inbreeding and
relationships in forest trees
1. Phenotype
2. Selection (seed orchards, seed prod areas)
Why is selection important?
We want the best!
Do we want big trees?
Tree Quality
P = G + E
P = G + E
Is environment important?
E
Environment
↕
Natural environment + Silvicultural
Genetics & silviculture together
Genetic diversity
P = G + E
P = G + E
Product = genetics + environment
Product = genetics + environment
Tree Quality
Is environment important?
Forestry and Forest Products
Propagation
Population

(seed orchards)
Selection
Breeding
Population
Base
Population
Activity cycle for tree breeding
Crossing
Planting stock
for plantations
Propagation
Population
(seed orchards
or clone hedges)
Selection
Breeding
Population
Base
Population
Activity cycle for tree breeding
Crossing
Planting stock
for plantations
6. Genetic gain
Gain ƒ ( i h
2
σ
p
)
Where:

σ
p
→ variability
h
2
→ genetic control
i
→
selection intensity
Selection for development of
seed orchards
¾ We selectively thin unpedigreed seed
production areas, and pedigreed seed
orchards, to achieve genetic gain
¾ Must thin to one tree per plot in seedling seed
orchards, to avoid inbreeding within families
Forestry and Forest Products
Col 1
2
3 4 5 6 7 8 9 10 11 12
Rep 1
1

1412442355747453610 5
2 4 15 12 18 50 13 19 44 60 25 32 16
352551149 84851 62059 328
44637265340302954 739 923
5 2 58 43 22 34 21 17 14 38 56 27 33
Rep 2
1 40 30 52 12 27 59 4 13 49 60 31 39

2 5 21450335124233418 746
3 6 44 37 45 35 58 10 43 54 17 16 3
4 29 38 48 1 53 28 26 8 56 55 15 22
5 20 36 32 9 25 11 47 19 21 41 42 57
Rep 3
1 35 22 25 42 6 55 15 39 43 47 5 13
2 37 8 20 48 3 46 59 38 10 40 36 4
319 9182358 7141128325160
4 41 29 16 57 17 34 21 1 53 45 26 12
5 49 56 30 2 52 24 50 27 31 33 54 44
Rep 4
1274544133720163025 64054
2 14 57 29 28 2 41 11 9 58 8 49 10
3 18 24 55 7 22 47 34 15 42 1 4 50
4234339 3 531524632531738
12 21 33 36 60 56 35 51 26 48 59 19
Rep 5
1211859433114492847302041
2 3 40 7 33 51 17 13 50 9 12 58 42
3 60 54 2 56 39 38 5 25 55 34 44 36
426462715482232 4351053 6
5 8 11 19 52 45 16 1 37 23 29 57 24
5 reps x 5 rows x 3 m = 75 m
Row
30 m
90 m
z 60 ½ -sib families
z 5 tree row plots
z 5 replicates
z each family occurs

only once in
replicate
Seedling seed orchard with 60 ½-sib families
Forestry and Forest Products
Within-plot thinning of seed orchards
First assessment
Replicate 1 Replicate 2
Plot 1 Family 2 Plot 1 Family 3
Plot 2 Family 3 Plot 2 Family 5
Plot 3 Family 6 Plot 3 Family 4
Plot 4 Family 5 Plot 4 Family 1
Plot 5 Family 4 Plot 5 Family 2
Plot 6 Family 1 Plot 6 Family 6
Related trees adjacent
- mating results in
inbreeding
Forestry and Forest Products
Self-fertilised family -
inbreeding depression of yield
seed
pollen
Forestry and Forest Products
selfed
outcrossed
Inbreeding
depression of growth
in control-crossed
progenies of
E. camaldulensis
(Petford) at 30

months - trial near
Gympie,
Queensland
Inbreeding problems
Petford
Rwanda landrace
Petford
Vietnam
landrace
Forestry and Forest Products
E. camaldulensis:
natural seed source
vs local land race
Australian seedlot
(collected from natural
stand, one year younger)
Vietnam land race
Forestry and Forest Products
Open-pollinated eucalypt family -
insects are the main pollinators
20% selfs
70% outcrossed
10% inbred
(relative mating)
seed
pollen
pollen
pollen
Forestry and Forest Products
Within-plot thinning of seed orchards

First assessment
Replicate 1 Replicate 2
Plot 1 Family 2 Plot 1 Family 3
Plot 2 Family 3 Plot 2 Family 5
Plot 3 Family 6 Plot 3 Family 4
Plot 4 Family 5 Plot 4 Family 1
Plot 5 Family 4 Plot 5 Family 2
Plot 6 Family 1 Plot 6 Family 6
Forestry and Forest Products
Second assessment
Replicate 1 Replicate 2
Plot 1 Family 2 Plot 1 Family 3
Plot 2 Family 3 Plot 2 Family 5
Plot 3 Family 6 Plot 3 Family 4
Plot 4 Family 5 Plot 4 Family 1
Plot 5 Family 4 Plot 5 Family 2
Plot 6 Family 1 Plot 6 Family 6
Within-plot thinning of seed orchards
Related trees adjacent
- mating results in
inbreeding
Forestry and Forest Products
Within-plot thinning of seed orchards
Third assessment
Replicate 1 Replicate 2
Plot 1 Family 2 Plot 1 Family 3
Plot 2 Family 3 Plot 2 Family 5
Plot 3 Family 6 Plot 3 Family 4
Plot 4 Family 5 Plot 4 Family 1
Plot 5 Family 4 Plot 5 Family 2

Plot 6 Family 1 Plot 6 Family 6
Unrelated trees adjacent
- outcrossing
Forestry and Forest Products
Outcrossed family (control-pollinated
single-pair cross)
seed
pollen
Unrelated parent
trees
Forestry and Forest Products
Seed production area (SPA)
–
unpedigreed