Liu GuiFeng

Analysis of genetic relationship in 12 species ofSection Strobus with ISSR markers

Genetic relationship of 12 species ofSection Strobus was analyzed with ISSR markers. 117 loci were detected with 12 ISSR primers. Percentage of polymorphic bands (PPB) varied from 5.93% to 19.92%.P. pumila had the highest levels of genetic differentiation andP. flexilis had lowest. Total genetic diversity (HT) of 12 species inSection Strobus was 26.21%, of which intraspecific genetic diversity (Hs) was 7.66%, and interspecific genetic diversity (DST) was 18.55%, and the genetic variation in interspecies accounted for 70.78% of the total genetic diversity. According to the cluster results of genetic distance, the 12 species were classified into two groups. The first group includedP. griffithii, P. armandi, P. fenzeliana, P. kwangtungensis, P. strobus, P. monticola andP. wangii. The second group includedP. albicaulis, P. pumila, P. flexilis, P. sibirica andP. koraiensis.

Construction and analysis of a cDNA library from yellow-fruit ginseng ( Panax ginseng C.A.Meyer.) leaf tissue

The total RNA was isolated from yellow-fruit ginseng (Panax ginseng C.A. Meyer) leaf tissue. A cDNA library of panax ginseng leaves was constructed by using pDNR-LIB vector according to the SMART cDNA library construction kit protocol. We obtained 378 high quality sequences (GenBank accession number: ES672876-ES673253). ESTs were annotated, analyzed by BlastX and functional classified based on gene ontology, the results showed that 221 ESTs showed significant similarities to gene sequences in Nr database and were known genes, 21 ESTs were non-significance and unknown function genes, and 136 ESTs were considered novel genes. Most of the ESTs appeared to be related to physiological and cellular processes.

Study on the provenance test of Dahurian Larch selection of best provenance

In this paper, it is studied that the growth characters of the progeny of 16 provenance oflarix gmelinii within the all 13 experimental sites by means of the analysis of variance, provenance stability, productivity index, rank correlation, synthetic index selection and PCA.The provenances were divided into three patterns: The first type have low and steady productivity; The second type have high but unsteady productivity; The third type is between the productivity of the first and second type. Through the analysis on the feasibility and the reliability of the provenance early selection, the best provenances which lie in the southeast of the Xiaoxingan Mt. are regarded as the best and suitable for a large afforestation areas ofLarix gmelinii. Then in the north of Xingan Mt., the local or the northwest provenances of the Xiaoxingan Mt. should be used. The genetic gain was calculated on the basis of the provenance heritability and the utilization of the best provenance were evaluated in this paper.

Molecular Cloning and Expression Analysis of Nine ThTrx Genes in Tamarix hispida

Thioredoxins are small conserved proteins that play key roles in the oxidative stress response. In this study, nine Trx genes, including five Trxhs, three Trxms, and one Trx-like gene, were cloned from Tamarix hispida. The roles of these ThTrx genes were investigated under various abiotic stress conditions. Expression profiles of the nine ThTrx genes in response to different abiotic stresses in leaf and root tissues were constructed using quantitative real time-polymerase chain reaction. Differential expression of all nine ThTrx genes was observed (>2-fold) in response to NaCl, PEG, or CdCl2 stress in at least one tissue, indicating that all of these genes act in abiotic stress responses. All ThTrx genes were induced (>2-fold) by abscisic acid (ABA) treatment in the leaves and especially in the roots, suggesting that ABA-dependent signaling pathways regulate ThTrxs. These results demonstrate that ThTrx expression constitutes an adaptive response to abiotic stress in T. hispida and plays an important role in abiotic stress tolerance.

Genetic relationship of interspecies for eight birch species

Genetic relationships of eight species of genusBetula were evaluated using ISSR marks. A total of 236 loci were generated from 17 ISSR primers. Percentage of polymorphic bands (PPB) varied from 5.93 to 19.92. The highest and the lowest level of genetic differentiation were detected inB. ovalifolia andB. maximowicziana Regel respectively. In these eight species, genetic diversity of birch (HT) was 24.38% and the genetic variation (GST) interspecies was accounting for 79.36% of total genetic variation. According to the cluster results of genetic distance, the eight species were classified into three groups asB. davurica, B. ovalifolia, B. platyphylla andB. pendula for one group;B. schmidtii, B. costata andB. ermanii Cham. var.communis for one group, andB. maximowicziana Regel for another group. The result of cluster is consistent with traditional morphological classification

Geographic variation pattern ofLarix olgensis

On the basis of the data of provenance test for 10 years in the total natural range ofLarix olgensis from 10 seeds collection sites, the geographic variation patterns have been made by means of canonical correlation analysis: (1) The basic variation patterns of growth characters is in vertical gradual change along the elevation gradient as principal, and gradual change along the latitude as supplement. (2) The Xiaobehu provenance with low elevation and low equivalent latitude is the good gene resource center ofL. olgensis. It has the genetic characters of rapid growth, high stability and fine timber quality. (3) The synthetical interaction between water and heat factors is the major factor to produce the variation ofL. olgensis and the temperature is the principal one. (4) Among the genetic variations of geographic population characters, the variation of growth is the most obvious one, and it could be taken as the main character for provenance division. (5) By allocating the seeds from the low equivalent latitude region to the northern suitable afforestation areas, the greater genetic gain could be obtained.

The effect of low temperature adversity on male flowers and pollen inLarix olgensis

The electric conductivity of pollen life-force and male flowers ofLarix olgemis on condition of low temperature adversity has been respectively measured by means of fluorescent dying method and conductivity method in 1992 and 1994. The results indicate that: (1) If the same clonal pollen is treated at equal time at different low temperatures, there are significant differences in pollen life-force, the pollen life-force is the largest between O°C and -3°C, in higher or lower temperature range, the pollen life-force will decrease. The measurement of electric conductivity of male flowers proves that the low temperature of below -3°C is the main reason that the cell membrane is damaged and the pollen life-force decreases. (2) The same clonal pollen life-force at the same low temperature will gradually decrease with the increasing of frozen time. Its main reason is that suffocation and losing body fluid result in the damage of cell membrane, the measurement of electric conductivity of male flowers can prove that. (3) If pollen is treated with the same low temperature, the humidity will be the main factor of affecting pollen life-force. (4) There are significant differences inLarix olgensis’s resistance against low temperature in its different growth stage, the male flower’s resistance of near pollen spreading period is low. (5) The resistance is different within clones. (6) The resistance against low temperature ofLarix can be increased by means of chemical treatment.

Study on the cutting propagation technique ofPicea koraiensis

The cutting propagation technique ofPicea koraiensis was carried under automatic spraying of total sunlight by adopting the same year epicormic branches from different trees with different age treated by different hormones in different concentration and time and the orthogonal and randomized block was designed. The results were as follows: (l)The rooting rate of the cutting reached at least 87 percent, when the cuttings were from the seed tree with the age below 25 years old and the cuts of the cuttings base were in vertical angle and on the fine sand medium. (2) The sequence of effective factors affecting the rooting rate were the style of cut, the age of seed tree and the type of medium. (3) There are significant differences of rooting rate among different clones.

The occurrence and development of the adventitious roots forming green shoot cutting ofLarix olgensis

The experiment with the green shoot cutting propagation ofLarix olgensis was made in the Maoer Mountain Forestry Farm on July 5, 1990. After the callus formed of the cutting base before adventitious roots came out the materials were collected from the cutting base and fixed in FAA solution. By the paraffin sections and anatomical observation, the results indicted that it needed 40 days from the cutting to the rooting. The induced primordium of the cutting was endogenous in origin, which came from: (1) vascular cambium of the callus, and became roots; (2) meristematic cell population in the intersect between the cambium and xylem ray of the cutting base. There were extruding, crushing process and enzymolysis when the adventitious roots broke through the outer layers in two rooting types.

Effect of low temperature on pollen vitality ofLarix olgensis

After the treatment of pollen oflarix olgensis at the different low temperature, the pollen vitality was observed by using fluorescent staining method. Several conclusions were obtained: 1) 0°C–3°C is the best temperature range for storing pollen ofLarix olgensis. 2) At the same temperature, humidity is the key factor influencing the pollen vitality. 3) Different clones shows different resistance to low temperature. Among the ten clones 2# clone shows the highest resistance.