2013 Vol. 26, No. 6
Somatic embryogenesis not only plays a significant role in understanding the mechanism of embryogenesis, but also in improving the breeding of Larix kaempferi (Lamb.) Carr. The somatic embryogenesis receptor-like kinase 1 (SERK1) gene is considered as an essential element involved in the early stage of this process. The expression pattern of the homolog of SERK1 of L.kaempferi in different culture conditions was studied. LaSERK1 shared all the characteristic domains of the SERK family. The qRT-PCR showed that LaSERK1 was highly expressed in L.kaempferi early embryogenic cells cultured in the mature medium. These results suggest that LaSERK1 might perform a significant role during early somatic embryogenesis of L.kaempferi, and might be a potential marker of early embryogenic cells.
The strong tolerance to low temperatures is critical to the survival, reproduction and wax production of Ericerus pela. To investigate the effects of cold stress on heat shock protein (hsp) expression in Ericerus pela, the transcriptional expression pattern of 7 hsps (hsp21.5, hsp21.7, hsp40, hsp60, hsp70, hsc70, and hsp90) in second-instar male larvae was examined by quantitative real time PCR (qRT-PCR). The results showed that all the hsps were inducible by cold stress except hsc70. The expression of hsp21.7, hsp70 and hsp90 were drastically up-regulated. The results indicated that many hsps correlate with cold-stress tolerance in Ericerus pela.
This study examined the genetic variations of eight-year-old Pinus massoniana trees in their growth, morphologic traits, and resin yielding capability, and analyzed the genetic correlation among these traits using a progeny test at Laizhou Experimental Forest Farm in Nanping City, Fujian Province. The superior families and individuals were selected for oleoresin producing. The results showed highly significant family effects for oleoresin yielding capability, growth and crown traits. Compared with growth and crown traits, more variation existed for oleoresin yielding capability and the coefficient of variation was 61.91%, suggesting a wide base for choice. The oleoresin yielding capability was under moderate genetic control, the family heritability and individual heritability were 0.42 and 0.31, respectively. Analysis result of genetic correlation among traits showed that a strong positive genetic correlation existed between oleoresin yielding capabilty and DBH, height and individual volume, which indicated both resin yield and growth could be improved simultaneously in the breeding progress. Positive correlation was also showed between tree crown size, whorl number, living branch number and oleoresin yielding capability. DBH was the most reliable trait for indirectly selecting high-yielding oleoresin trees. Twenty superior families and sixteen superior individuals were selected according to the oleoresin yield and individual volume. The genetic gain for oleoresin yield and individual volume were 52.54%~154.40% and 0.22%~31.85%, respectively.
The fast-growing and high-yielding Cunninghamia lanceolata pure stands in south China were used to analyze quantitatively the competition intensity among C.lanceolata stands by adopting improved Hegyi's simple competition index model, and the individual tree growth model was built. Then the Hegyi's simple competition index model was used for whole stand by diameter class model, in order to broaden individual tree growth model to whole stand growth model. Meanwhile, the visual simulation technique could provide a theoretical basis for restoring and rebuilding the stand spatial structure more realistically.
Based on Standardized major axis estimation, the allometric rules between internode biomass and internode length, between internode biomass and needle biomass, between internode sectional area and internode biomass, and between internode sectional area and needle biomass of current-year shoots on first-order branches, second-order branches and third-order branches of 10 years old Pinus tabulaeformis trees were analyzed by power exponent equation, and the independent data were used to test the allometric models. The results show that the correlation coefficient between predicted and observed values is higher than 0.85 except the case between sectional area and needle biomass, and the correlation is statistically significant. The size scale between internode biomass and needle biomass is less than 1, which means that the biomass allocation rate is higher for internode biomass than for needle biomass. The size scale between sectional area and needle biomass is close to 1, which means that there is symmetrical relationship between these two attributes.
The Huangfengqiao State-owned Forest Farm in Hunan Province was selected as a test area. A typical even-aged Chinese fir pure plantation with regular boundary was chosen as the research object. The tree height, DBH, crown width, crown height, under-branch height and the tree location information were measured. The parameterized tree controlled by the crown shape was simulated by researching the crown shape function and using the Direct 3D technique. The conversion method of the tree model format was studied in order to provide the model data to the stand scene. The simulation method of the stand scene was researched and the stand scene was simulated by using MOGRE technique. The results show that the simulation algorithms of the parameterized tree are simple and applicable, the tree-measuring factors can be directly used by the verisimilitude model of the tree which can describe the individual difference, and the verisimilitude scene can be quickly and effectively constructed with MOGRE technique. The data can be easily acquired and the methods which have strong applicability can realistically simulate the individual tree and the stand scene and provide new ideas for the study of forest competitive relationship, stand growth, stand structure and stand management.
The germination and storage characteristics of bamboo seed (caryopsis) were tested with six bamboo species including Dendrocalamus asper (JA et JH Schult) Backer ex Heyne (nut-like caryopsis), D.sinicus Chia et JL Sun (typical caryopsis), D.membranaceus Munro (nut-like caryopsis), Schizostachyum sp. (typical caryopsis), Qiongzhuea tumidinoda Hsueh et Yi (berry-like caryopsis), and Chimonocalamus pallens Hsueh et Yi (typical caryopsis). No dormancy was observed during the process of germination of these seeds. The fresh and ripe seeds begin to germinate in 5 15 days after sowing, and finish within 15 days. The results of test showed that the field germination rates were: 84.0% (D.asper), 81.0% (D.membranaceus), 43.3% (D.sinicus), 73.5% (S.sp.) and 25.0% (Q.tumidinoda). The medium, MS+BA 0.5+NAA 0.2, was the best for the bamboo seed germination. The germination rate of seed stratified at 20℃~25℃ was significantly higher than that at 4℃. Sowed after 10 days' soaking in water, the seed germination rates of D.asper, D.membranaceus, S.sp. and Q.tumidinoda dropped to 0 5.5%. When stored at 4℃ or at 20℃~25℃ with humidity of 10%-15%, the seed germination rates of these six bamboos decreased gradually and dropped to 0~4.0% after 90 days. It could increase seed lifespan of Ch.pallens when stored in soil at 4℃.
Since the root distribution characteristics show spatial pattern of water and nutrition absorption of each plant species, they decide belowground competition degree in agroforestry system. The method of stratified digging was adopted to study the root dry biomass, root length density, fine root length density and root diameter in walnut (Juglans regia L.)/cassia (Triticum aestivum L.) agroforestry pattern with spacing of 3 m×8 m. The results showed that total root length density of monocultured walnut was 7% higher than that of the intercropped walnut; the monocultured walnut had higher fine root length density than the intercropped walnut at each soil layer; while the intercropped and the monocultured walnuts had slight difference in root biomass and root diameter. The root diameter of monocultured cassia was 27.73% greater than that of intercropped cassia, while their difference in root length density and root biomass were minor. Root biomass and root length of intercropped walnut accounted great proportion in the agroforestry system. In which, horizontally, cassia distributed its root mainly at 4.0 m and 2.5 m south to the tree line, while walnut spread its root mainly at a 150 cm distance scope to its trunk. And vertically, intercropped walnut distributed 64.79% of root biomass and 61.17% of root length at 30~80 cm soil profile, while 59.54% of intercropped cassia root distributed at 0~20 cm soil profile in the walnut/cassia intercropping. The above results suggest that intercropped walnut and cassia staggered root distribution position and avoided strong belowground competition. Thus, walnut-cassia agroforestry model has great potential to develop economically and ecologically in the low hilly area of north China.
Taking different forest types in Dawujia Watershed of Ao'han County, Chifeng city, Inner Mongolia as the research object, the correlation between water conservation function and stand factors was studied in order to evaluate the level of water conservation function by stand factors. The results of research show that the average height, the average diameter at breast height, crown width, crown thickness, volume per hectare, annual volume increment, canopy density, ground cover coverage, undergrowth coverage, and community structure are the most important factors impacting and related to water conservation function. These ten key factors can be used to evaluate the water conservation function of forest. For litter layer, the stand factors closely related to water conservation function are the average diameter at breast height (0.734 7), annual volume increment (-0.806 8), crown thickness (0.464 7), crown width (-0.674 6), community structure (-0.370 0), litter cover (0.677 6), volume per hectare (-0.617 9), and canopy density (-0.587 2); For soil layer, the stand factors closely related to water conservation function are the average height(0.592 1), the average diameter at breast height (0.275 0), volume per hectare (0.827 5), canopy density (0.317 3), annual volume increment (0.767 7), and crown width (0.749 0);For both the litter layer and soil layer, the stand factors closely related to water conservation function are canopy density (0.831 7), volume per hectare (0.817 2), undergrowth coverage (0.652 5), average diameter at breast height (0.644 7), and the crown width (0.521 2); From the viewpoint of the total water storage capacity of forest, the most important factors are the ground cover coverage (0.462 6) and the volume per hectare (0.315 5).
In order to view the genetic basis of Xinjiang walnut germplasm resourses, the genetic diversity of 30 walnut cultivars (Juglans regia L.) authorized or approved by Xinjiang Uygur Autonomous Region Forest Tree Cultivar Registration Committee were investigated by using FISH-AFLP. Eight pairs of EcoRⅠ+3/MseⅠ+3 primer combinations were used to amplify the genomic DNA. 981 out of totally 1011 AFLP bands were polymorphic and the average percent of polymorphic bands (PPB) was 97.5%. The value of effective number of alleles (Ne) estimated by different primer combinations ranged from 1.188 7 to 1.234 7 with an average of 1.208 5; Nei's gene diversity (H) ranged from 0.118 3 to 0.141 2 with an average of 0.129 7 and Shannon's information index (I) ranged from 0.184 6 to 0.225 8 with an average of 0.206 6, which revealed a moderate level of genetic diversity. Unique fingerprintings for 30 walnut cultivars were established by 8 primer combinations in the research.
The number and spatiotemporal change characters of the vegetation in natural forest protection area of Qingshui County, Gansu Province, were investigated and the external and internal differences during the period of 1996 to 2004 were compared with two indicators: the vegetation area which came from the land-use classification map by the maximum likelihood classification (MLC) and the vegetation fraction by the NDVI dimidiate pixel model based on two Thematic Mapper (TM) images, by using spatial analysis and statistical techniques. The results indicated that the forest area and the vegetation fraction improved more evidently in the natural forest protection area than in the other area during the period of 1996 to 2004 in the study area. In addition, the degree of the vegetation change differed among different types of the natural forest protection area, the key ecological reserve area of the natural forest protection showed the most remarkable improvement. The results of the study suggest that this method is feasible and ecosystem conditions of the natural forest protection area have been improved as the result of the implementation of classified management policies.
Ubiquitin-conjugating enzyme (E2) is one of three key enzymes in the ubiquitin-proteasome pathway (UPP). And it's very important in the protein degradation pathways depend on ubiquitin or N-end rule, including identify the target protein, interaction with ubiquitin-protein ligating enzymes (E3), and so on. A full length cDNA sequence of E2 was cloned by Solexa sequencing technology and named UBE2-J2. This cDNA codes 239 amino acids, and has significant amino acid sequence identity and similarity with E2s from other organism. The UBE2-J2 protein has an ubiquitin-conjugating enzyme E2 catalytic (UBCc) domain from 8th to 122nd amino acid residue. There are 17 residues to compose Ubiquitin thioester intermediate interaction residues, 5 residues to compose E3 interaction residues and the 87th residue is the active site cysteine on conserved domain UBCc. UBE2-J2 is a class Ⅱ member of E2 family of Camellia oleifera according to bioinformatics analysis.
Soil anti-erodibility is one of the important parameters for evaluating the ability of soil resistance to soil erosion. Based on the comprehensive investigation on soil physical and chemical properties, and incorporated into bioindicator, by using principal component analysis, all the 16 anti-erodibility indices could be optimized to 7 indices which were water-stable aggregates at size>0.5 mm and >0.25 mm, destructive rate of aggregates at size >0.25 mm, coefficient of dispersion, degree of aggregation, viscous grain powder at size 0.05 mm and viscous grain at sizeEucalyptus grandis are discussed and the result showed that the soil anti-erodibility index followed the order of one-year-old stand>two-year-old stand>four-year-old sprout stand>bare land. Taking the 7 indexes (X) as independent variables and soil erodibility index (Y) as dependent variable, the soil erodibility model equation in the rare earth mining area is: Y = 0.309X1+0.038X2 -0.161X3 -0.643X4 +0.491X5 -0.032 8X6 +0.129X7 +41.637. The correlations among factors are significant and the model fits well.
In order to evaluate the nutrient status and the heavy metal concentrations in the leaves of evergreen broad-leaved forest at Nanling Nature Reserve, the characteristics including contents, relationships and variations of N, P, K, Ca, Al, Na, Mg, Mn, Ni, Cu and Pb, were detected in the leaves of 16 dominant species in this reserve. The contents of N and P in leaves of the selected tree species were below the averages, while the concentrations of Ca, K and Mg were within its normal ranges of the terrestrial plants in China. The levels of Mn in the leaves detected were near the background values of Guangdong plants. Fortunately, the concentrations of Al, Ni, Cu, and Pb were within their respective normal ranges in plants. Based on the ratios of leaf N to P, the 16 species detected were all P-limited. Although these species are not suffering from Al, Ni, Cu and Pb at present, there is a potential risk from toxic metals activated by soil acidification caused by acid deposition in south China. Regular monitoring and research on the elemental concentrations in the leaves as well as forest soils in the reserve are scientifically necessary.
Aiming at studying the growth and development of root system as well as its distribution of poplar plantation with ground drip irrigation cultivation (DIC), a comprehensive survey was conducted with methods of digging out whole root system of individual and digging out root pieces in different vertical and horizontal locations in the soil of 2-year-old poplar plantation with DIC and conventional irrigation cultivation (CIC) at sandy land of the former Yongding River watercourse in Beijing. A systematic analysis was made on the quantity, length and biomass of individual and stand root system as well as their vertical and horizontal distribution characteristics under the two cultivation conditions. The conclusions of study are as follows: (1) The depth of poplar taproot with DIC is 1.3 m, while that with CIC is 4.5 m, the distribution range of lateral roots of poplar with DIC is 1.8 times and 1.2 times that of CIC in direction along row and cross row, respectively. The quantity of lateral roots of poplar with DIC is 2.0 times that of with CIC. (2) The total length and biomass of individual root system of poplar with DIC is 1.8 times and 1.2 times that of with CIC respectively, while the total length and biomass of taproot and level-I lateral roots of poplar with DIC are similar to those with CIC, and the total length and biomass of level-Ⅱ lateral roots and level-Ⅲ lateral roots of poplar with DIC are far more than those with CIC. (3)The stand root system and biomass of poplar with DIC is 2.0 times and 1.1 times that of with CIC respectively, while the total length and biomass of the roots with diameter of 5≤DD D≥15 mm of poplar stand with DIC are similar to those with CIC, and the total length and biomass of the roots with diameter of DDDDDD<1 mm) of poplar stand with CIC relatively distributes in the soil around the tree.
In order to reveal the characters of ant fauna at Nangun River Nature Reserve in Yunnan, China, the ant specimens were collected through sample-plot and search-collecting methods. In total, 166 species belonging to 54 genera and 11 subfamilies of Formicidae were recognized. The distribution types and faunal composition were analyzed. The ant fauna in the nature reserve has a typical Oriental character. At genus level, the ant fauna is closest to Australasian region, and farthest to Nearctic region. At species level, the Oriental species are in the dominant position, closest to Palaearctic region, and farthest to Neotropical region. Inside the zoogeographic districts of China, the ant fauna in the nature reserve has a typical character of Southern China district, and close to the fauna of Southwestern and Central China districts.
This research investigated and selected 4 natural populations of Picea likiangensis in Yunnan province, based on its natural distribution. The length, width, dry weight and C, N, P contents in needles of the 4 populations were measured to survey the phenotypic variation of natural populations and the relationship between the phenotypic variation and their altitude of distribution areas. The methods of ANOVA analysis, multi-comparison and correlation analysis were used for analyzing the data measured. The results showed that, there were remarkable (PPPPPPP<0.05) positively correlated.
In recent years, Agrilus mali Matsumura has outbroken in the Xinjiang wild fruit forest, and become the primary threat to Malus sieversii. In early study, the larvae of Agrilus mali were divided into six instars. However, the particular reason and method were not mentioned, and the larvae of Genus Agrilus were usually divided into four or five instars. For better pest forecasting and control strategies, the determination of larval instars was studied again. A.mali larvae were sampled periodically in forest, and the eggs were collected to hatch the first instar larvae. Three characteristics (i. e. peristoma width, urogomphus length and body length) were measured by binocular microscope with an eyepiece micrometer. According to the Dyar's law, the data were managed with frequency analysis, and examined by one-way ANOVA method, Crosby ratio and checked with larvae which were molting when sampling. The results showed that, the A. mali larva has five instars, and all three determination characteristics are effective except body length.
In order to explore the salt tolerance mechanism of Machilus thunbergii, the effects of salt stress on seedling biomass, root morphology, sodium and potassium absorption and distribution were studied. The results showed that the above-ground biomass increased slightly under lower salt stress conditions, while the below-ground biomass, root length and root surface area showed a downtrend. The above-ground growth was limited under high concentration salt stress, while the under-ground growth was not subject to significant restrictions. The absorption of Na+ in root increased under salt stress, but that of K+ decreased. The ability of Na+ transporting from root to leaf and stem was weakened. The accumulation of Na+ in stem and leaves was less. With the decreased absorption of K+, the ratio of Na+/K+ also continuously increased. With the increased concentration of salt stress, the ability of K+ absorption in roots increased. The ability of K+ transporting from root to leaf and stem was enhanced, which resulted in significant increase of K+ in the leaves and stem. The accumulation of Na+ in the under-ground was significantly greater than that in above-ground, while the K+ content in above-ground increased significantly, which played a key role in maintaining normal growth and metabolism of M. thunbergii.
In order to set up the genetic diversity system of Eucommia ulmoides Oliver based on SSR molecular markers, the establishment of SSR-PCR reaction system and screening out SSR marker primer showing high polymorphism were studied. A L9(34) orthogonal design was performed to optimize the main factors of the SSR-PCR reaction system. The results indicated that the best SSR-PCR reaction system for E.ulmoides was DNA template 1 μL (30~60 ng·μL-1), 2×Taq PCR Master Mix 10 μL, primer 1 μL with the total volume of 25 μL. The PCR reaction system had high stability and repeatability, the pairs of SSR primers with high polymorphism were gotten. The 8 E.ulmoides samples' DNA sequence was amplified with 13 pairs of SSR primers by SSR-PCR technique, 34 alleles were detected, 2.6 alleles were detected from per site on average. Each allele's effective number was 1.751 5, and the h value was 0.379 8, the average I value was 0.643 3. This study is helpful in using SSR molecular marker to analyze genetic diversity and genetic relationship in E. ulmoides.
The leaf nutrient, biomass and carbon reserve of 9-year-old Populus×euramericana cv. ‘74/76’ stump grafting stand with 26-year-old P.×xiaozhuanica W.Y.Hsu et Liang cv.‘Popularis’as rootstock, 26-year-old P.×xiaozhuanica W.Y.Hsu et Liang cv.‘Popularis’ and 9-year-old P.×euramericana cv. ‘74/76’ planting stands were compared. The result showed that the average increment and the annual average increment of stump grafting stand were greater than the two planting stands. The total nitrogen content in leaves of stump grafting stand was the highest, and it was 1.26 times and 1.05 times as much as that of the planting stands of Populus×xiaozhuanica W.Y.Hsu et Liang cv.‘Popularis’ and P.×euramericana cv. ‘74/76’ separately. The total phosphorus content of stump grafting stand was 1.3 times as much as that of planting stand of 26-year-old P.×xiaozhuanica W.Y.Hsu et Liang cv.‘Popularis’, but there was little difference between stump graftin stand and planting stand of 9-year-old P.×euramericana cv. ‘74/76’. The total potassium of stump grafting stand was 46.6% and 95.8% lesser than that of the planting stands of P.×xiaozhuanica W.Y.Hsu et Liang cv.‘Popularis’ and P.×euramericana cv. ‘74/76’. The biomass of aerial parts and the biomasses of trunk, branches and leaves of stump grafting stand were 1.84, 1.80, 1.76, and 3.00 times as much as that of planting stand of P.×euramericana cv. ‘74/76’ separately. The total root biomass of the stump grafting stand was 1.42 times and 7.68 times as much as that of planting stands of 26-year-old P.×xiaozhuanica W.Y.Hsu et Liang cv.‘Popularis’ and 9-year-old P.×euramericana cv. ‘74/76’. There was an obvious advantage in carbon reserve from all the parts of the stump grafting stand and the carbon sequestration capacity was the highest, which was 2.66 times and 1.62 times as much as that of planting stands of 26-year-old P.×xiaozhuanica W.Y.Hsu et Liang cv.‘Popularis’ and 9-year-old P.×euramericana cv. ‘74/76’. These showed that the stump grafting stand had more advantages than planting stands.