Nghiên cứu đặc điểm biến dị và khả năng di truyền về sinh trưởng và mục ruột của keo tai tượng (acacia mangium willd ) trong các khảo nghiệm hậu thế thế hệ 2 tt tiếng anh

MINISTRY OF EDUCATION AND TRAINING - MINISTRY OF AGRICULTURAL AND RURAL DEVELOPMENT

VIETNAMESE ACADEMY OF FOREST SCIENCES

‘

LA ÁNH DƯƠNG
ĐOÀN NGMAIỌC DAO

RESEARCH ON GENETIC VARIATION AND HEREDITARY
ABILITY IN GROWTH AND HEART ROT IN SECONDGENERATION PROGENY TEST OF Acacia mangium

DOCTOR OF PHYLOSOPHY IN FORESTRY
THESIS SUMMARY

Ha Noi - 2019
1


The thesis has been completed in Vietnamese Academy of Forest
Science

Supevisor: 1. Ass.Prof. Dr. Nguyen Hoang Nghia
2. Dr. Phi Hong Hai

Chair of PhD thesis defense Committee:
PhD thesis Reviewer 1:
PhD thesis Reviewer 2:
PhD thesis Reviewer 3:

The dissertation was defended at PhD thesis committee at Institutional

level of Vietnamese Academy of Forest Sciences
At ……………….on ………..(date),……….(month), 2019

The thesis can be found at: National library and Vietnamese Academy of
Forest Sciences library
2


3


INTRODUCTION
1. Problem statement
Acacia mangium has been planted in Vietnam since early of 1960s (Le Dinh Kha,
Nguyen Hoang Nghia, 1991). Acacia mangium seedling improvement program was
started from 1980s. As a result of this program, many origin species of Acacia
mangium such as Pongaki, Cardwell, Iron Range, SW Cairns and Bloomfield have
been recognized as technical progress seedling source and applied in practice. In the
program, the research results about variation and heritability of the first generation
trials which carried out in Hanoi showed that the heritability for growth varies from
low to moderate, while it fluctuations from medium to high for cellulose content,
collapse rate, wood density, modulus of elasticity, modulus of rupture and wood
shrinkage rate. From this result, the preeminent families in first generation trials were
selected, collected and used to develop second-generation progeny test in 2008-2009
period (Ha Huy Thinh et. al., 2011). By the end of 2016, there have been 14 varieties
of Acacia mangium recognized by the Ministry of Agriculture and Rural
Development (MARD), thereby greatly contributing to improving the productivity
and quality of plantation production forests in Vietnam.
The plantation in large-scale monoculture cause to strongly development of
disease, typically Heart rot which are common in Acacia mangium. Diseases caused

by some fungal species which reduce the quality of wood, affect the pulp properties,
reduce wood recovery and mechanical and physical properties of wood. The factors
causing Heart rot diseases can be limited by breeding and appropriate silvicultural
measures (Lee, 2002; Rimbawanto, 2006). However, research about Acacia mangium
varieties improvement before 2012 only focused on assessing the variation and
hereditary ability in growth, stem quality and quality of wood chip and sawn timber
of first generation progeny test. The study of Heart rot disease is very limited and
only assessed the variation of decay between different origins. Therefore, it is
necessary to study the genetic variation related to Heart rot disease at the family level
4


at different age levels, thereby selecting varieties that are resistant to disease or ability
to recover well after the plants become infected by diseases.
Based on about reasons and inheriting the field trial setup in research project
"Research on improvement of varieties in order to increase wood quality and yield
for some common forest plantation species" and the project "Development of wood
tree varieties for economic plantation in the period of 2006-2010", the thesis"
research on genetic variation and hereditary ability in growth and Heart rot in secondgeneration progeny test of Acacia mangium” has been carried out with the aim of
contributing to scientific background to guide strategies for improving Acacia
mangium variety in Vietnam.
2. Scientific and practical significance of the thesis
- Scientific significance
The dissertation results have added insights on the characteristics of genetic variation,
hereditary ability related to Heart rot disease and traits association level between
growth, wood quality and Heart rot disease, as a basis for Acacia mangium breeding
selection.
- Practical significance
+ The thesis has identified the indirect evaluation method of Heart rot disease by
ArborSocnic 3D device with high accuracy.

+ Selected a number of Acacia mangium families from second-generation progeny
test with some characteristic such as fast growth, high wood quality, low level Heart
rot.
3. Research object
+ Research goal
Identifying the genetic variation and hereditary ability characteristics of some
important traits that serve as a scientific basis to contribute to further study about

5


Acacia mangium seedling improvement toward high yield and ability to resist decay
disease.
+ Specific object
- Identifying the genetic variation characteristics of some traits related to growth,
wood quality and decay disease.
- Identifying method for evaluating Heart rot disease by ArborSocnic 3D device.
- Identifying hereditary ability, genetic gain related to Acacia mangium breeding
selection.
- Identifying the relationship between growth, wood quality, mechanical and
physical properties of wood traits and Heart rot disease.
4. New contribution of the thesis
- The first time in Vietnam, the method of indirect evaluation Heart rot disease
by ArborSonic 3D device with high precision for Acacia mangium has been applied.
- Having a comprehensive assessment the level of genetic variation, hereditary
ability of decay disease and growth, wood quality traits on A. mangium in Vietnam.
5. Research subject
The subjects of the study are the A. mangium families which selected from different
seed sources in the second generation progeny test. The testing models were setup in
2008-2009 period.

6. Scope of research
(1) The dissertation only conducted research on the degree of variation and
genetic ability in Acacia mangium families in the second generation posterior trial at
different ages in Hanoi, Nghe An and Binh Duong.
(2) The study identifies the method of assessing decay disease by new method of
using ArborSonic 3D device, comparing with the methods which are widely used,
carried out on 30 A. mangium trees in 9 year old which were planted in Doan Hung 6


Phu Tho. Then, this method was tested on 120 trees of 40 families (3 trees/family)
and compared with the method of assessing decay level of Caroline (2006) in the
second generation progeny test in Bau Bang.
(3) Due to the high budget consume of mechanical and physical wood properties
test, and must be destructive trees in the trial, the research about correlation between
decay level and mechanical and physical wood properties was only conducted in 120
trees (3 trees/family) of 40 families in the second generation posterior trial in Bau
Bang.
(4) Researches on identifying fungal pathogens and affecting of site conditions
on Heart rot diseases have been carried out, however, scope of this research is about
breeding, these research results related to fungal pathogens and affecting of site
conditions on Heart rot disease are not presented in this thesis.
7. Thesis structure
Introduction: 6 pages
Chapter 1: Literature review: 32 pages
Chapter 2: Content and research method: 18 pages
Chapter 3: Result and discussion: 53 pages
Chapter 4: Conclusion, limitation and recommendation: 3 pages

7

Chapter 1
LITERATURE REVIEW
1.1. Over the world
Acacia mangium is native species of Australia, Papua New Guinea and Indonesia.
The species is fast growing and adaptable on a variety of site conditions. Acacia
mangium therefore plays an important role in reforestation and plantation programs.
Many researches on this species have been conducted in many countries such as
researching on biological characteristics, selecting varieties, planting techniques as
well as usability.
In the 1990-2000 period, studies by Awang and Taylor (1993); Susumu and
Rimbawanto (2004); Harwood and Williams (1991); Turvey (1996); and Nirsatmanto
et al. (2003) was often focused on finding high-yielding provenances.
In the 2000-2010 period, studies of genetic variation at the family level of A.
mangium had shown that genetic variation from low to moderate for growth traits and
stem quality and target average value for wood density trait. The hereditary
correlation between growth and wood density is positive (Nirsatmanto and Kurinobu,
2002; Arnold and Cuevas, 2003; Susumu and Rimbawanto, 2004; Nirsatmanto et al.,
2004; Kim et al., 2008; Khasa et al., 1995). There are many successful story related to
tree breeding (Walker and Haines, 1998; Darus, 1993; Gerad et al., 1999; Griffin et
al., 2010).
Research about disease has also been focused. In recent time, disease
management has always been one of the main goals of variety improvement research
programs (Mayank et al., 2012). Research about diseases on acacia species has also
been introduced in Ken Old et al. (2000). Decay disease is a common disease in
tropical acacia species and has been the subject of research by many authors, such as
Lee et al. (1988); Lee and Maziah (1993); Mahmud et al. (1993); Ito and Nanis
(1997); Mehrotra et al (1996). The level of decay disease can be very high in Acacia
8

mangium plantation, ranging from 50-98% (Zakaria et al., 1994); Ito and Nanis,
1994; Basak, 1997).

Decay disease in Acacia mangium is caused by a typical fungus of Basidiomycetes
class (Hood, 2006), which breaks down both cellulose and lignin, eventually
changing the color of wood to yellow-white, porous or fibrous (Caroline et al., 2006).
They usually occur in older trees, but sometimes in 2-year-old trees (Lee, 2002),
especially in large-scale plantations (Mahmud, 1993). Fungal pathogens might
infiltrate to Acacia mangium via wounds caused by stem canker diseases, or from
damaged stems, pruned branches and broken branches (Mahmud et al., 1993; Ito and
Nanis, 1994, 1997; Barry et al., 2004). Signs or symptoms of this disease usually
don't show to the outside of trees.
Research related to disease-resistance breeding have been carried out for many
forestry species in the world and achieved positive results. Zakaria et al. (1994)
demonstrated that in A. mangium, the higher the diameter, the greater the incidence of
decay disease.
1.2. In Vietnam
The Acacia mangium variety improvement in Vietnam has been conducted since
the 1980s. In the 1990s, provenance trials were setup synchronously and
systematically. The results show that the genetic variation among the origin of Acacia
is quite large (Le Dinh Kha and Nguyen Hoang Nghia, 1991); Mai Dinh Hong et al.,
1996; Le Dinh Kha, 2003). Prospective sources are Pongaki (PNG), Oriomo (PNG)
and Bimadebun (PNG), Deri - Deri (PNG), Cardwell and Pascoe (Qld), Ingham (Qld)
and Mossman (Qld).
Based on promising origins, provenances test/first generation test in combining
with the establishment of Acacia mangium seed orchards in Hanoi and Binh Phuoc in
1996-1998 (Le Dinh Kha, 2003). Results showed that there are significantly different
between stem volume, growth and wood quality among families. Heritability for
9

growth traits range from 0.12 to 0.33 and vary according to age. Heritability of wood
mechanical and physical properties of Acacia mangium is high, ranges from 0.21 to
0.38 for cellulose content, collapse rate, density, modulus of elasticity, modulus of
rupture and wood shrinkage rate. However, heritability cumulative of relatively low
at only about 1.6-9.5%. Relationship between growth traits is a strong correlation
between ages of 3, 5, 9, and 11. Heritability correlation between growth traits and
wood quality, the author noted that diameter is strongly correlated with modulus of
rupture and cellulose content (Doan Ngoc Dao, 2012).
In the second-generation progeny test of A. mangium, the assessment of genetic
variation at 3-4 years old showed that there are significantly different between
diameter, height, stem volume, wood quality among families. (Phi Hong Hai et al.,
2015). Heritability of the growth traits are low to moderate (h2 = 0.04-0.30).
However, hereditary cumulative covariance of most traits exceeded 5-7%.
Genetic gain in theoretical for growth and stem straightness is 8.8% to 23.4%.
Research on the genetic correlation between growth traits and wood quality (Phi
Hong Hai et al., 2015) shows that improvement in growth parameters will have a
positive effect, but not significantly on stem straightness and wood density, and may
not strongly affect to modulus of elasticity, stiffness and wood shrinkage rate.
Studies about A. mangium propagation in Vietnam have been conducted in many
different ways such as marcotting, grafting, cuttings and tissue culture (Le Dinh Kha,
1992; Ha Huy Thinh et al., 2010; Phi Hong Hai et al., 2015).
Research about disease on Acacia also have been carried out. A recent study
estimated the incidence of this disease in A. mangium, A. auriculiformis and A. ranges
from 7.1 to 12.5%; 9.2 - 18.4% and 10.2 - 18.2% respectively (Pham Quang Thu et
al., 2016). Research related to characteristics of Acacia mangium, Acacia
auriculiformis, Acacia hybrid in Dong Ha - Quang Tri showed that Acacia mangium
at the age of 7 years has the percentage of hollow trees accounting for 40% (Nguyen
Trong Nhan, 2003). Research by Le Dinh Kha and Doan Ngoc Dao (2011) on

assessing the incidence of decay contents for 39 lowland acacia species, including 9
10


different provenance Acacia at 17 years of age in Da Chong – Hanoi, the result
showed that the incidence of Acacia mangium is very high, from 50.8-96.6%.
There is a difference about decay rate between provenances of Acacia mangium.
The study results also indicated there is not relationship between tree growth and the
decay incidence rate, not follow any rule. Both A. mangium origin of fast growth and
the slow growth have low rate and high rate of of heart rot.
1.3. Insight from literature review
The research results have identified suitable growing conditions for Acacia
mangium as well as many achievements in seedling improvement. However, the
quality of wood is not high due to the use of low quality varieties that was not
improved or improved at a low level (provenance). Wood from A. mangium
plantation still has many disadvantage such as high rate of shrinkage after drying,
high rate of wood death knots, Heart rot, etc. Some new varieties have recognised by
characteristics of fast growth, trunk quality, mechanical and physical properties of
wood. However, the indicators for varieties recognized are not relate to disease
resistance, including Heart rot diseases that are very common in Acacia mangium.
Research on Heart rot disease is still limited and only assessing the level of Heart
rot among provenances. The study about decay disease should focus on determining
the level of decay disease at all ages group of tree; the relationship between the level
of decay disease and the seedling sources and family as well as the impact of the
environment on decay disease.

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Chapter 2

CONTENT, MATERIAL AND RESEARCH METHOLOGY
2.1. Research content
1) Research about level of genetic variation related to growth, trunk quality and
Heart rot diseases on A. mangium in second-generation progeny test.
2) Evaluating level of Heart rot by applying ArborSonic 3D device;
3) Identifying heritability, the relationship between different traits; understanding
the effect of interactions between genotypic context and living environmental on
straits such as growth traits, stem quality and Heart rot diseases on Acacia mangium;
4) Estimate the genetic gain of growth traits, stem quality, and Heart rot disease in
second-generation progeny test of A. mangium.
5) Selecting a number of Acacia mangium families with high productivity and
resistant to Heart rot disease.
2.2. Research object
A. Mangium varieties group includes 253 families from 16 provenances in
second-generation progeny test in Hanoi, Nghe An, Binh Duong and 30 average
Acacia trees (age of 9 years) from plantation production forests in Doan Hung - Phu
Tho.
2.3. Research method
2.3.1. Heart rot evaluation method
+ Heart rot incidence rate (%): automatically measured by ArborSonic 3D;
measurement by percentage of diseased area/basal areas of tree at breast height of
individual tree.

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+ The level of Heart rot (Di-3D): measured and simulated by ArborSonic 3D
device; the device will calculate based on the porosity of wood and the different
colors of the entire 3D section at breast height of trunk. Through actual inspection of
trunk cross section, based on color and incidence of decay measured by Caroline

method (2006) as wel as result from ArborSonic 3D measurement, author divided the
level of Heart rot in to 5 level, from 0 point to 4 point in order to assess the incidence
of diseases on each individual Acacia mangium tree in second-generation progeny
test (Figure 2.1)

0 point

1 point

2 point

-

4 point

3 point đieđiểm

Figure 2.1: The level of Heart rot from 0 - 4 points (in above image, the picture on the
left is a wood cross section,; the picture on the right is the ArborSonic 3D device
image)
- Determine the correlation between decay level by ArborSonic 3D device and
Caroline method (2006) and TCVN 8928: 2013

13


Selecting 30 average Acacia mangium trees at 9 year old from production forest
in Doan Hung - Phu Tho. Before felling trees, the assessment of decay level by
ArborSonic 3D is done on a standing tree. Then the trees were cut and take out 30
pieces of wood (1 cross section piece/tree) at breast height. Samples of wood cutting

cross section were smoothed, took photographs and then assessed the level of decay
according to the method of Caroline (2006) and TCVN 8928: 2013. On images of
wood cutting cross section, the actual rate of Heart rot was determined by using
Mapinfor software to measure the ratio of areas of diseased parts to the basal area of
the cutting wood cross section.
- Assessment of decay level by Caroline’s method (2006) (Di): Level of decay was
ranks from 0-4, the higher the score, the greater the level of decay.
2.3.2. Tree growth and trunk quality data collection method
Growth parameters such as diameter at breast height (D 1,3), height (H) and height
below branches (Hdc) were measured for all trees in the trial; Stem straightness (Dtt),
branch size (Dnc): is group according to 5 levels (scale from 1 to 5 points) according
to Vietnam standard 8761: 2017.
2.3.3. Methods of determining the physical and mechanical properties of wood
- Determining wood density by applying water displaced method (Olesen, 1971).
- Sampling and determining mechanical and physical properties were carried out
according to Vietnamese standards (TCVN 8044: 2009).
2.3.4. Data analysis
Data was analysised according to method suggested by Williams et al. (2002).
Some common statistic softwares were used such DATAPLUS 3.0 and Genstat 12.0
(VSN International), SAS 8.0 (SAS Institute, 2002) and ASREML 4.0 (VSN
International).

14


Chapter 3
RESULT AND DISCUSSION
3.1. Variation in growth and trunk quality of A. mangium in the secondgeneration progeny test
3.1.1. Variation in growth and trunk quality of A. mangium in the secondgeneration progeny test in Ba Vi
Ở tuổi 9, kết quả phân tích thống kê cho thấy sinh trưởng và chất lượng thân cây

thân cây giữa các gia đình trong khảo nghiệm hậu thế thế hệ 2 tại Ba Vì có sự sai
khác rất rõ rệt (Fpr.<0,001). Biến dị giữa các gia đình là khá lớn, từ 15 cm đến 26,4
cm cho đường kính, từ 15 m đến 20,7 m cho chiều cao và từ 2,8 đến 4,6 điểm cho độ
thẳng thân.
At the age of 9 years, the statistical analysis showed that the growth and quality
of trunk among families in the second-generation progeny test in Ba Vi had
significant differences (Fpr. <0.001). The variation between families is quite large,
from 15 cm to 26.4 cm in diameter, from 15 m to 20.7 m for height and from 2.8 to
4.6 points for trunk straightness.

Figure 3.1: Exceeding (%) in volume, diameter, height and trunk quality of 10 GDTN
compared to 10 GĐXN and technical progress (TBKT) in Ba Vi

The group of 10 families had the best growth in stem volume (483.8 dm 3/tree),
exceeding 33.2% compared to the volume of TBKN (363.2 dm3 / tree) and exceeding
141.9% compared to volume of group for 10 slowest growth families (200 dm 3/tree).
The exceeding of trunk straightness is about 16.4% and 41.9% compared to TBKN
average and 10 growth slowest families respectively.
3.1.2 Variation in growth and trunk quality in the second-generation progeny test
in Quy Hop
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In Quy Hop, at the age of 9 years, the growth index and trunk quality among
families in progeny test also showed significant differences (Fpr. <0.001). Growth of
diameter, height and stem volume of families with a range of variation is less than
that of trial at Ba Vi, from 11.6 cm to 18.8 cm for diameter, from 12.4 m up to 20 m
for height and from 86.9 dm3/tree to 276.9 dm3/tree for stem volume. The group of 10
best growth families has an average stem volume of 244.1 dm 3/tree which is
exceeding 41.5% compared to that TBKN test (172.5 dm3) and exceeding 118.5%

compared to average volume of 10 lowest growth families (111.7 dm3/tree).

Figure 3.2: Exceeding (%)of volume, diameter, height and trunk quality of 10 GDCN
compared to 10 GĐXN and TBKN in Quy Hop

3.1.3 Variation in growth and stem quality in the second-generation progeny test in
Bau Bang
The statistical analysis results showed that the range of variation between families
in Bau Bang is larger than that for testing in Ba Vi and Quy Hop, specifically from
15.4 cm to 33.7 cm for the diameter, from 12.6 m to 24.2 m for height and from 131.9
dm3/tree to 911.6 dm3/tree for stem volume. Moreover, the coefficient of variation for
growth in each family are also very large and there is a significantly different in
growth and trunk quality (Fpr. <0.001).

16


Figure 3.3: Exceeding (%) in volume, diameter, height and trunk quality of 10 GDCN
compared to 10 GĐXN and TBKN in Bau Bang
Average volume of the 10 best families is about 775.0 dm 3/tree, and this number
is higher than that for natural forest (455.0 dm 3/tree) by 70.3%; and over 241.4%
compared to average volume of the 10 slowest growth families (227.0 dm 3/tree). The
variation in trunk quality is very large, from 0.9 to 4.8 points for stem straightness
and from 0.9 to 4.3 points for small branches.
3.2. Evaluating level of Heart rot by applying ArborSonic 3D device;
3.2.1 Relation between level of Heart rot measured by ArborSonic 3D device and
Caroline method (2006) in the second-generation progeny test in Bau Bang

The sound waves have been successfully used to evaluate decay disease for many
forest species (Ladislav Reinprecht and Jaroslav Hrivnák, 2012), Teak (Kyaw Ko

Win et. Al., 2015) with high accuracy, from 89 to 94%.
Correlation analysis of decay level by ArborSonic 3D and Caroline method
(2006) for 120 trees (3 trees/family) of 40 Acacia families at second-generation
progeny test in Bau Bang, Binh Duong shows that there is a linear correlation at
strong level between decay level measured by ArborSonic 3D and Caroline’s method,
with a correlation coefficient is 0.77 (Figure 3.4).

17


r=0,77±0,12

Figure 3.4: correlation at strong level between decay level measured by ArborSonic
3D and Caroline’s method (2006) for tree at age of 8 years in Bau Bang
The relation between phenotypic and genotypic related to decay level was
determined by using specialized breeding software (ASReml 4.0). The result showed
that the phenotypic correlation and genotypic correlations between decay levels by
these two methods are 0.77 ± 0.15 and 0.80 ± 0.18 respectively. The results also
showed that these correlation coefficients is existance and significant. Thus, it can be
confirmed that ArborSonic 3D device can be used to assess decay disease for Acacia
mangium with high accuracy, is about 80%.
3.2.2 Biến dị về mức độ mục ruột và tỷ lệ cây bị bệnh giữa các gia đình Keo tai
tượng trong các khảo nghiệm hậu thế thế hệ 2
3.2.2 Variations related to level of Heart rot and the incidence of diseased among
Acacia mangium families in the second-generation progeny test
Statistical analysis results for data collected from Bavi showed a significant
difference in the level of decay contents among Acacia mangium families (Fpr
<0.009). At the age of 9 years, the level of Heart rot was not high, ranging from 0.0 to
2.1 points (according to scale of 0 to 4 points). The group of 10 families with the
lowest level of decay has from 0.0 to 0.1 point, of which only family that was

numbered at No. 72 has no disease (0 points).

18


Evaluation result of diseased for Acacia mangium family planted in in Ba Vi
showed that 42/112 families have no decay disease or have low level of decay
disease, accounting for 37.5% of the total Acacia mangium families. There are 70 out
of 112 families have a high rate of decay disease, ranging from 33.3-50.0%. Among
the 15 families with the lowest incidence of decay disease in this trial, there are 10
families were belong to group of 42 families which have no decay disease or have
low level of decay disease.
In Quy Hop, there is significant difference in the level of decay among families
(Fpr <0.001). At the age of 9 years, most families are infected by decay disease in
different level, ranging from 0.1 to 1.9 points. The group of 10 families with the
lowest level of decay showed the level from 0.1 to 0.6 points. The results of assessing
the proportion of diseased trees show that 15/120 families do not have disease and/or
the level of decay disease is low, accounting for 12.5%; there are 105/120 families
were infected by decay disease, shared to about 87.5%.
In Bau Bang, there are significantly difference in the level of decay between
Acacia mangium families (Fpr <0.001). At the age of 8 years, Acacia mangium
families have different levels of decay contents, ranging from 0 to 1.9 points (on a
scale of 0 to 4 points). There are only 6 out of 100 A. mangium families do not
affected by decay disease. The group of 10 families has the lowest level of decay
ranges from 0 to 0.1 point. The results of assessing the rate of A. mangium families
infected by disease planted in Bau Bang shows that 81 out of 100 families do not
suffer from decay disease (accounting for 81.0%) and only 19 out of 100 families
affected by decay disease. A. mangium families with the lowest level of decay were
among the non-diseased families (the percentage of diseased tree is 0%).
3.3. Identifying heritability, the relationship between different traits;

understanding the effect of interactions between genotypic contexts and living
environmental on straits such as growth traits, stem quality and Heart rot
diseases on Acacia mangium
19


3.3.1. Heritability, cumulative hereditary variation coefficient of growth
characteristics and trunk quality of A. acacia
For tree testing in Ba Vi, heritability related to growth traits of A. mangium
families was low at age 3 to average at ages 5, 7 and 9 years. Specifically, the
heritability related to diameter ranges from 0.18 to 0.43 and heritability related to
height is from 0.11 to 0.44. Heritability related to growth traits tend to increase
according to age of trees. For trunk quality traits, heritability fluctuated at low levels
and are quite stable in different ages (Table 3.1).
Table 3.1: Heritability related to growth traits, trunk quality and level of Heart rot at
Ba Vi, Quy Hop and Bau Bang.
Traits

Unit

TBK

Age

N

(year)

h2±sed

CVa (%)

Bavi, Hanoi
D1.3

cm

21,5

9

0,43±0,08

7,4

H

m

18,4

9

0,40±0,08

4,1

Dtt

point

4,4

9

0,11±0,06

10,7

Dnc

point

2,0

5

0,12±0,03

35,1

Di

point

1,5

9

0,14±0,05

24,5

Quy Hop, Nghe An
D1.3

cm

15,0

9

0,35±0,02

2,5

H

m

16,6

9

0,28±0,03

2,5

Dtt

point

3,8

9

0,13±0,04

16,7

Dnc

point

4,0

9

0,09±0,03

13,3

Di

point

2,1

9

0,23±0,05

10,8

Bau Bang – Binh Duong
D1.3

cm

22,6

8

0,46±0,12

8,3

H

m

21,1

8

0,21±0,11

1,6

Dtt

point

3,2

8

0,19±0,12

30,4

Di

point

1,3

8

0,19±0,43

23,8

20


In Quy Hop, heritability of growth traits also increased inline with age, but this
coefficient was only reached low levels in all ages from 3 to 9 years, ranging from
0.21 to 0.35 for diameter and from 0.18 to 0.28 for height. In contrast, cumulative
hereditary variation coefficient in this trial fluctuated from age 3 to age 9. The trunk

quality indicators have a larger cumulative hereditary variation coefficient, ranging
from 11.4 to 27.9%.
In Bau Bang, heritability of growth traits for trees from age 3 to age 8 also
reached low to moderate levels and also tended to increase with age, from 0.12 - 0.42
and reach the highest nmber at age 8 (0.46) for the diameter, from 0.13 to 0.21 for the
height. However, cumulative hereditary variation coefficient is vary, from 4.9 to 8.3
for the diameter, from 1.6 to 4.2 for the height and instability.
3.3.2. Hereditary ability of colonic colic disease in second-generation progeny test

For tree (age of 9) in Ba Vi trial, heritability was 0.14 for decay diseases, but the
cumulative hereditary variation coefficient related to rate of Heart rot were very high
(CVa = 24.5%). At Quy Hop trial (age 9), heritability of decay disease was higher
than that in Ba Vi, but it was only low (h2 = 0.23), however cumulative hereditary
variation coefficient still targeted 10.8%. In Bau Bang, heritability related to decay
disease was h2 = 0.19 and the cumulative hereditary variation coefficient was CVa =
23.8 (Table 3.1).
3.3.2. The relationship between growth trait, trunk quality trait, Heart rot disease
and effect of the interactions between genotypic context and living environmental
on straits such as growth traits, stem quality and Heart rot diseases on Acacia
mangium
- Correlation of growth characteristics, trunk quality, wood properties and decay
diseases on Acacia mangium
21


In Ba Vi, the genetic correlation coefficients of growth indicators between ages 3,
5, 7, 9 were strong to very strong (r = 0.82-0.97), phenotypic correlations were at
from weak to very strong (r = 0.21-0.91). In Quy Hop testing model, there was
correlation between genotypes related to growth indicators with correlation
coefficient from moderate to very strong (r = 0.59-0.94) for trees at age 3, 5 and 9

years. However, the correlation coefficient for trees at age from 5 years to 9 years
was moderate (r = 0.48). In Bau Bang, growth traits at ages 3, 6, 7 and 8 were
correlated with genotypes, correlation coefficient were ranging from moderate to
very strong (r = 0.47-0.98).
Correlation between growth trait and trunk quality trait for trees at Ba Vi and Quy
Hop showed that there are existing positive genotypic correlation and positive
phenotypic correlation between growth traits (diameter, height) at strong level (0.70
to 0.90). However, diameter and height are positively and weakly correlated with
trunk quality indicators, from 0.2 to 0.57 (Table 3.2)
Table 3.2: Hereditary correlation between growth and trunk quality of A. mangium at
Ba Vi and Quy Hop
Trait

D1.3

H

Dtt

Dnc

0,90±0,07

0,28±0,31

0,46±0,18

*

0,57±0,28

0,52±0,16

*

0,52±0,16

Testing in Bavi – Hanoi
D1.3

*

H
Dtt
Dnc

*

Testing in Quy Hop – Nghe An
D1.3
H
Dtt
Dnc

D1.3

H

Dtt

Dnc

*

0,86±0,20

0,24±0,31

0,20±0,35

*

0,38±0,34

0,33±0,28

*
*

Genetic correlation between decay disease and growth traits and some wood
physical and mechanical properties of Acacia mangium was conducted at Bau Bang
22


trial. The results showed that the density of wood and the shrinkage ratio in two
directions tangential and radial are negatively correlated, from moderate to very
strong (-0.47 to -0.75), meanwhile, the Modulus of elasticity (MoE) has a weak
positive correlation with the degree of decay, (correlation coefficient at 0.21-0.37)
and nonexistent (Table 3.3). Modulus of rupture (MoR) is positively and strongly
correlated with the rate and level of decay (correlation coefficients is about 0.51 and

0.64).
Table 3.3: Correlation between decay level and growth index and wood
characteristics of Acacia mangium in Bau Bang - Binh Duong
Trait
Di - 3D
Di

D1.3

H

0,45±0,35 0,84±0,82
0,85±0,59 0,23±0,53

Den

MoE

MoR

T/R

0,47±0,1

0,21±0,6

0,64±0,1

0,52±0,18

0

3

3

0,56±0,1

0,37±0,1

0,50±0,1

4

8

7

0,75±0,17

- Interaction between genotypic-environment and seed improvement in 3 progeny
test for Acacia mangium
Genetic correlation coefficients for growth and stem quality between trials Hanoi
and Nghe An, Hanoi and Binh Duong and Nghe An and Binh Duong were weak to
medium, from 0.16 to 0.41 for growth traits and weak correlations from 0.10 to 0.16
for trunk quality indicators, except for diameter and height traits between Hanoi Nghe An ranging from 0.51 - 0.52, however the error is very high. Genetic
correlation related to Heart rot level between Hanoi and Nghe An, Hanoi and Binh
Duong, Nghe An and Binh Duong have weak correlations, from 0.013 to 0.17,
however the errors is very high and these correlations do not exist.
3.4. Genetic gain of growth traits, stem quality, and Heart rot disease in secondgeneration progeny test of A. mangium

3.4.1. Genetic gain of growth traits, stem quality, and Heart rot disease

23


With selective intensity is about 5-10%, the development of the best individual tree
from the best families in second-generation progeny test can lead to increase of
genetic gain at about 11.9 – 19.9% for diameter, 3.9 to 9.2% for height and the level
of Heart rot from 6.0 to 7.1%.
3.4.2 Quality of Acacia mangium seedlings sources from 1st and 1.5 generation
seed orchards in Vietnam
In Ba Vi and Quy Hop, there is no difference between the different seed sources
in terms of growth and stem quality. However, growth of progeny from the seed
orchards in Ba Vi, Bau Bang and the Philippines is higher than that of the seed
families from Australia.
3.5. Selecting a number of Acacia mangium preeminent families with high
productivity and resistant to Heart rot disease
In Ba Vi, the group of 06 preeminent families have a growth in volume higher
21.1% - 57.2% than that of TBKN. The level of decay in these families is only 0.1 to
0.5 points.
In Quy Hop, the group of 04 preeminent families have a growth in volume higher
20.5% - 26.8% than that of TBKN. The level of decay in these families is only 0.6 to
1.0 points.
In Bau Bang, the group of 08 preeminent families have a growth in volume
higher 22.9% - 100.4% than that of TBKN. The level of decay in these families is
only 0.0 to 0.4 points.

24

CONCLUSION, LIMITATION AND RECOMMENDATION
1. Conclusion
There was a significant difference in growth, stem quality and incidence of Heart
rot among A. mangium families in 3 second-generation progeny test in Ba Vi, Quy
Hop and Bau Bang (F.pr <0.001 ).
The 3D ArborSocnic device can be used to detect decay and decay rot on standing
trees with highly accuracy and this is a new method.
Average heritability related to growth traits in Ba Vi, Quy Hop and Bau Bang are

range from 0.07 to 0.46 for the diameter; from 0.05 to 0.44 for height; and low for
decay diseases (0.14 to 0.23). The cumulative genetic variation coefficient is from
10.8 to 24.5%.
There is positive and very strong genotypic and phenotypic correlation between
growth traits with correlation coefficient is from 0.70 to 0.90. There is positive and
weakly correlated between diameter, height and trunk quality indicators (correlation
coefficient is from 0.2 to 0.57).
There is negatively correlated, at moderate to very strong (-0.47 to -0.75) between
Heart rot and wood density, the shrinkage ratio according to 2 directions tangent and
radial; The is positive and weak correlation between modulus of elasticity (MoE) and
level of decay with correlation coefficient is about 0.21-0.37. Modulus of rupture
(MoR) have positively and strongly correlated with the rate and degree of decay
(correlation coefficients are 0.51 and 0.64).
There is weak to moderate correlated about genotype-environment, growth, stem
quality, and decay incidence between testing model in Hanoi and Nghe An, Hanoi
and Binh Duong, Nghe An and Binh Duong.
In Ba Vi, the group of 06 preeminent families have a growth in volume higher
21.1% - 57.2% than that of TBKN. The level of decay in these families is only 0.1 to
0.5 points. In Quy Hop, the group of 04 preeminent families have a growth in volume
25