**3.1 The effect of environmental conditions on the genetic diversity of** *D. punctatus tabulaeformis* **populations**

The genetic diversity among 3 natural populations of the Chinese pine caterpillar (*Dendrolimus punctatus tabulaeformis*) were tested by AFLP method in one *Pinus tabulaeformis*-*Dahurian larch* mixed forest and two *Pinus tabulaeformis* pure forests in Pingquan county. Besides, investigations on plant species diversity, forest crown density, incidence extent, gradient and exposure of three forest communities were taken, while dilution heat method and semi-micro Macro Kjeldahl method were used to determine the content of organic matter and nitrogen in soil(table32-36).

The result of principle component analysis shows that the growth status is main factor which influent genetic diversity of *D. punctatus tabulaeformis* populations. Besides, site conditions had some effects on it. An integrated effect was produced by all site conditions, so main factor could not be judged(table37).

Mixed forest has a great influence on gene flow among different populations of *D. punctatus tabulaeformis*, because gene flow between populations in mixed forest and in pure forests was lower than that of two pure forests. Gene flow between populations in pure forest with larger species abundance and in mixed forest was higher than between population in pure forest with lower species abundance and in mixed forest, which showed that the correlation between gene flow among different populations and species abundance of pine forests is negative.


Note: I,II: pure forests; III: mixed forest.

340 The Dynamical Processes of Biodiversity – Case Studies of Evolution and Spatial Distribution

population *A Ae I Ho He h P* 

0.4903 0.3587 0.4417 0.4054 0.4472 0.4287 0.4302 0.4109 0.2811 0.3690 0.4543 0.3674 0.3765 0.4747 0.4063 0.2781 0.3649 0.4481 0.3634 0.3722 0.4736 87.50 75.00 75.00 87.50 75.00 80.00 87.50

0.6501 0.4981 0.6245 0.8020 0.6180 0.6385 0.8091

Note: *A:* Number of alleles per locus; *Ae:* Effective number of alleles per locus; *I:* The Shannon

*Ho:* Observed heterozygosity; *He:* Expected heterozygosity; *P:* Percentage of polyporphic loci Table 30. Genetic diversity parameters of 5 sub-populations in *D. punctatus tabulaeformis*

POP pop1 pop2 pop3 pop4 pop5

Table 31. Nei's genetic identity and genetic distance of 5 sub-populations in *D. punctatus* 

Fig. 18. Phylogenetic relationship of 5 sub-populations of *D. punctatus tabulaeformis* based on

Nei's distance of SSR markers and clustered using UPGMA

\*\*\*\* 0.9322 0.7555 0.8826 0.7714 0.0703 \*\*\*\* 0.6573 0.8262 0.6953 0.2804 0.4197 \*\*\*\* 0.8568 0.7905 0.1249 0.1909 0.1546 \*\*\*\* 0.8775 0.2596 0.3635 0.2350 0.1306 \*\*\*\*

pop1 pop2 pop3 pop4 pop5 Mean Overall

> pop1 pop2 pop3 pop4 pop5

Note: See table 3-1 for abbreviations of population codes.

information index;

*tabulaeformis*

2.5000 2.5000 2.6500 3.0000 2.5000 2.6250 3.1250 1.8045 1.4960 1.7922 2.2521 1.8122 1.8314 2.1201

Table 32. Statistical results of stand condition investigation


Note: I,II: pure forests; III: mixed forest

Table 33. Species diversity index analysis of 3 populations in *D. punctatus tabulaeformis*

Genetic Diversity and Population Differentiation of Main Species

*spectabilis* 

and the ecological factors

of *Dendrolimus* (Lepidoptera) in China and Influence of Environmental Factors on Them 343

Correlation analysis by SPSS software of 4 populations of *D. punctatus spectabilis* in different geographical areas shows a significant negative relation between genetic diversity and elevation, and the genetic diversity within populations was positively related with the annual temperature and moisture. In opposite, the genetic diversity was weakly related with latitude. Besides, there was a positive relation between the genetic distance and the distance of elevation, which shows that geographic isolation has obstruct effect on gene flow (table38,39). Generally, the genetic distance between groups in the same population is certainly related

Altitude distance (m) 247 40 520 717 480 197 Genetic distances 0.0720 0.0521 0.0500 0.0808 0.0733 0.0813

Table 38. Correlation of the genetic diversitys within 4 populations of *D. punctatus spectabilis*

Shannon index

Latitude 0.0920 0.0730 Altitude -0.6250 -0.6380 Annual temperature 0.4800 0.4650 Annual moisture 0.5610 0.5640 Table 39. Relationship of genetic distances and geographical distances (altitude distances)

**3.3 The influence of ecological factors on the genetic diversity of** *D. punctatus* **Walker**  Three populations of *D. punctatus* Walker and three populations of geographic subspecies of *D. punctatus* Walker—*D. punctatus spectabilis* Bulter were examined and compared by RAPD. The influence of ecological factors on the genetic diversity is also discussed by the correlation analysis. The correlations between the genetic index and ecological and

> Altitude (m)

Annual Precipitation (mm)

> 1304.2 1480.7 1788.8 500 640 800

QC~TC TC~JC JC~SC SC~QC TC~SC QC~JC

Genetic diversity estimated by Nei index

Annual mean temperature (°C)

> 16.3 16.6 17.6 8.3 9.1 12.2

Annual mean moisture (%)

**3.2 The influence of ecological factors on the genetic diversity of** *D. punctatus* 

with the geographical distance and host(p<0.01,high notable correlativity).

Relationship quotiety 0.2780

Ecologocal variables Genetic diversity estimated by

latitude

26° 40′N 109°26′E 26° 07′N 109°46′E 28° 11′N 116°54′E 41° 11′ N 119°23′E 40° 27′ N 119°51′E 35°30′ N 119°37′E

Table 40. Origin and the ecological factors of the tested *D. punctatus* Walker materials

between 4 populations of *D. punctatus* spectabilis

geographic factors are significant (table40,41).

Code Location Longitude and

Huitong , Hunan Tongdao, Hunan Yujiang , Jiangxi Shenyang, Liaoni Jinzhou, Liaoning Qingdao, Shandong

HTM TDM YJM SYC JZC QDC


Note: I, II: pure forests; III: mixed forest

Table 34. Soil organic matter content of 3 populations in *D. punctatus tabulaeformis*


Table 35. Soil total nitrogen content of 3 populations in *D. punctatus tabulaeformis*


Table 36. The genetic diversity of 3 populations in *D. punctatus tabulaeformis*


Table 37. Principle component analysis of 3 populations in *D. punctatus tabulaeformis*

Community Sample plot FeSO4 volume of using (mL) Organic matter content (g·kg-1) Average

2 1 47.79 32.70

2 8 30.18 22.64

2 7 32.70 32.28

2 1.6 0.018 0.0107

2 1 0.009 0.0051

2 0.5 0.002 0.0049

Soil total nitrogen

content (g·kg-1) Average

1 12 20.12

3 8 30.18

1 13 17.61

3 12 20.12

1 3 42.76

3 11.5 21.38

1 1.1 0.011

3 0.6 0.003

1 0.5 0.002

3 0.7 0.005

1 1.2 0.012

3 0.45 0.001

Population numbers II I III Total Polymorphic bands 107 99 91 124 Polymorphism(%) 73.29 67.81 62.33 84.93 Observed number of alleles 1.7329 1.6781 1.6233 1.8493 Effective number of alleles 1.4804 1.3694 1.3441 1.4371 Nei's gene diversity 0.2683 0.2127 0.2024 0.2561 Shannon's Information index 0.3935 0.3193 0.3046 0.3877

Normalizing characteristic vector Factor 1 Factor 2 Factor 3 Shannon-weaver index of diversity 0.2403 0.3895 -0.1527 Simpson diversity index 0.2218 0.3852 0.1777 Gradient 0.1933 0.0608 -0.4748 Exposure 0.4173 -0.1938 0.1688 Crown density -0.1848 0.4354 -0.3303 Organic matter -0.3535 -0.3378 -0.1414 Nitrogen -0.3636 -0.1911 0.3595 Tree height -0.0288 0.4434 0.4204 Diameter at breast height -0.2028 0.216 0.4462 Incidence extent 0.4173 -0.1938 0.1688 Stand type 0.4173 -0.1938 0.1688

Table 37. Principle component analysis of 3 populations in *D. punctatus tabulaeformis*

Table 35. Soil total nitrogen content of 3 populations in *D. punctatus tabulaeformis*

Table 36. The genetic diversity of 3 populations in *D. punctatus tabulaeformis*

Table 34. Soil organic matter content of 3 populations in *D. punctatus tabulaeformis*

Acid standard solution volume of using (ml)

I

II

III

III

II

I

Note: I, II: pure forests; III: mixed forest

plot

Community Sample
