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1.
Dendrolimus superans is one of the important pests feeding on the needles of Larix gmelinii. Six standard compounds, (1R)-(−)-α-pinene, (1S)-(−)-α-pinene, ocimene, (1S)-(−)-β-pinene, R(−)-α-phellandrene and camphene, the main volatiles of L. gmelinii were used to test the electroantennogram (EAG) responses of moths. The results show that the order of the EAG responses of moths to seven concentrations of these six compounds were as follows: mated females > virgin females > unmated males, except for 0.1 μL/μL R(−)-α-phellandrene, where the order was: virgin females > mated females > unmated males. There are statistically significant differences between the EAG responses of virgin females and unmated males (p < 0.05), and also between mated females with virgin females and mated females and unmated males (p < 0.01), which suggests that the mated females are more sensitive to the volatiles of host plant. The results of EAG responses of the mated females, virgin females and unmated males indicate that they are more sensitive to R(−)-α-phellandrene than to the other volatile components. The active time for the EAG responses of both mated females and unmated males occurs during the night, i.e., from 20:00 to 04:00 hours. This is consistent with their eclosion, mating and oviposition periods. __________ Translated from Scientia Silvae Sinicae, 2007, 43(7): 55–60 [译自:林业科学]  相似文献   

2.
Plants initiate the development of defense mechanisms as soon as pests start to cause damage to them. In order to have a thorough understanding of the physiological mechanisms of the Pinus massoniana self-defense mechanism, and to provide a theoretical foundation for an effective ecological management of this plant, levels of tannin, polyamine and phenolic acids were analyzed in undamaged (UDL), insect-damaged (IDL) and artificially-damaged (ADL) leaves at different times. Results show that, although the content of tannin significantly increased in IDL and ADL compared to UDL, its peaks appeared earlier in ADL than in IDL treatment. Tannin concentration substantially increased again 48 h after IDL treatment. On the other hand, the damage mode considerably affected putrescine and spermidine levels in leaves. Their concentrations in IDL plants remained higher than in UDL after a relatively long time (72 h), but spermine was barely detected in any of the samples. In general, total content of phenol acids significantly increased in damaged leaf treatments (ADL and IDL), with a higher level in IDL for most of the investigated phenolic acids, except for ferulic acid. Our study showed that, when damaged by insects, Pinus massoniana rapidly produces substances required in resistance induction to insects in order to insure its self-protection. __________ Translated from Scientia Silvae Sinicae, 2006, 42(1): 55–62 [译自: 林业科学]  相似文献   

3.
Forest-air bathing and walking (shinrin-yoku) is beneficial to human heath. In this study the phytoncide (volatile compounds) released from Cryptomeria japonica plantation forest was characterized by using solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS). The main volatile compounds were α-pinene (19.35%), β-myrcene (16.98%), d-limonene (15.21%), and γ-muurolene (7.42%). Furthermore, the neuropharmacological activity of the essential oils from leaves of C. japonica (ECJ) was evaluated by several animal behavior tests. ECJ could prolong the sleeping phase of ICR (imprinting control region) mice in the pentobarbital-induced sleeping time model. Furthermore, both EJC and one of its monoterpenes, d-limonene, possessed potent anxiolytic and analgesic activities based on the results obtained from elevated plus maze and writhing tests. The volatile compounds released from C. japonica provide relaxing and stress-relieving effects on mice, and further study on the effect of phytoncide on humans is worthwhile.  相似文献   

4.
Alkaloids from Sophora alopecuroids were bioassayed with Clostera anastomosis for their antifeedant and growth inhibitory effects. The antifeedant rate in choice test reached 62%–86% at the dose 2.5 mg/mL, while in non-choice bioassay the rate was only 20%–29%. In choice bioassay, the antifeedant rate increased with larval instars of C. anastomosis and did not in non-choice experiment. The alkaloids also imposed a strong influence on the growth of C. anastomosis larvae, i.e., after feeding on the leaves treated with alkaloid, the larvae lost their weight, weight gain, and relative growth rate (RGR) significantly when compared with the controls. In the second day after treatment with the dose at 10 mg/mL of the alkaloid, the RGR reduced by 39.8%, and the food intake and the feces weight were respectively 57.7% and 57.4% of the controls. The approximate digestibility (AD) increased significantly, and the efficiency in converting digested food (ECD), and the efficiency in converting ingested food (ECI) decreased greatly after feeding the treated leaves. Moreover, the eggs laid per female were also inhibited by this alkaloid. The significance and prospect of the alkaloids in controlling forest insect pests were also discussed. __________ Translated from Scientia Silvae Sinicae, 2005, 41(4) [译自: 林业科学, 2005, 41(4)]  相似文献   

5.
Two groups of filial generations derived from two different Pinus massoniana complete-diallel crosses were analyzed. Results show that the general combining ability (GCA), specific combining ability (SCA) and reciprocal effects were significant for some growth traits, including height, DBH and volume index. The heredity of these growth traits was controlled by additive and non-additive genes, of which the additive genes played a dominant role. The epistatic effect was greater for group I (cross in 1992) than group II (cross in 1993). The SCA of P. massoniana growth traits was significantly greater than GCA, which may be related to different geographical provenance for parents and the indirect selection by GCA. Inbreeding depression was commonly observed for P. massoniana growth traits. The extent of inbreeding depression was −17.8%–−18.4%, −23.3%–−27.7% and −44.3%–−50.6% for height, DBH and volume index, respectively. It was observed that parents with small GCA values exhibited a greater extent of inbreeding depression. Large differences in hybrid vigor of different crosses were observed and the difference between original cross and reciprocal cross was not significant. Based on the volume index, 10 fine crosses were selected for two groups respectively, and the average increment of volume index was 59.41% and 41.76%, respectively, in comparison with the average of the testing groups, and was 100.58% and 74.61% in comparison with the local commercial variety. __________ Translated from Scientia Silvae Sinicae, 2008, 44(6): 28–33 [译自: 林业科学]  相似文献   

6.
In order to study the effect of tree crop intercropping on a young plantation of Populus tomentosa in the plains along the Yellow River, field experiments were conducted by observing the growth of the plantation, the nutrient content in leaves, the nutrient and water content in the soil, and the output of crops. The relationship between forest growth and nutrient content in the tree leaves and the soil were analyzed. Results show that tree crop intercropping in young plantations can not only improve soil water content, but also enhance the contents of organic matter and the available nitrogen, phosphorus and potassium in soil resulting in the vigorous growth of the individual trees. Diameter at breast height (DBH) was positively related to the contents of organic matter in the soil, and the contents of N, P and K in the tree leaves had correlation coefficients of 0.967, 0.955, 0.988 and 0.972, respectively. Whole tree leaf area, crown width, number of branches and the mean length of branches in the intercropped plantation (intercropped with watermelon and vegetables, peanut and winter wheat, and soybean) were, respectively, 1.70–3.0 times, 2.22–2.47 times, 1.0–1.41 times and 1.70–2.32 times of those of CK (without intercropping). Diameter at breast height (DBH) and tree height in the intercropped plantation were 50.5%–136.7% and 27%–59.5% higher than those of the CK, respectively. The study also showed that intercropping with watermelon and vegetables proved to have the highest economic return among the treatments adopted. Tree crop intercropping in young plantations is an effective measure to increase forest growth and economic benefit. __________ Translated from Journal of Beijing Forestry University, 2006, 28(3): 81–85 [译自: 北京林业大学学报]  相似文献   

7.
The adsorption properties of wood carbonized at various temperatures were investigated using a mixed gas containing toluene and α-pinene. Hinoki (Chamaecyparis obtusa) samples carbonized at 500°–1100°C were exposed to gas mixtures of toluene and α-pinene at 20°C. The samples carbonized at 500°–700°C only adsorbed toluene, whereas those carbonized at 800°–1100°C adsorbed both toluene and α-pinene. Analysis of the surface structure of the carbonized wood by nitrogen adsorption at liquid nitrogen temperature indicated that the sample carbonized at 700°C had micropores mainly 0.6 nm in diameter and few mesopores, whereas the samples carbonized at 900°C and 1100°C had mesopores and micropores larger than 0.8 nm in diameter. With the sample carbonized at 700°C, the flat-shaped toluene molecules could probably penetrate into the narrower pores, 0.8 nm in diameter, whereas the bulky globular-shaped α-pinene molecules could not. Carbonization at temperatures higher than 900°C probably enlarged the pore size and thereby reduced the selectivity of adsorption. The results revealed that wood carbonized below activation temperature has a unique flat-pore structure that seems to work as a kind of molecular sieving carbon, successfully removing only the harmful volatile organic compound (VOC), toluene, and leaving behind a pleasant aroma of α-pinene in the atmosphere.  相似文献   

8.
This is the first article to report the evaluation of a natural product used as an antisilverfish agent. Silverfish (Lepisma saccharina), primitive wingless insects, feed on a variety of materials, including paper, cotton, starch, and cereals. They can be a problem in libraries and other places where books, documents, and papers are stored. In this pilot study, the essential oil from leaves of Cryptomeria japonica was investigated to test its properties as a silverfish repellent and insecticide. The results from a repellency bioassay show that the essential oil significantly repelled silverfish. The repellent activity was 80% at a dosage of 0.01 mg/cm3. When silverfish were exposed to a concentration of 0.16 mg/cm3 of essential oil, they were killed within 10h. The chemical composition of essential oil, the emissions from a test chamber, and the residue left on filter papers previously soaked with the essential oil in a chamber were analyzed by gas chromatography-mass spectrometry. The components of the essential oil were found to be: elemol (18.22%), 16-kaurene (11.63%), 3-carene (9.66%), sabinene (9.37%), 4-terpineol (9.06%), β-eudesmol (5.70%), α-pinene (5.62%), and limonene (5.26%). Only some constituents of the essential oil compounds collected by solid-phase microextraction were found to be emitted in the test chamber. The main constituents were: 3-carene (21.03%), p-cymene (10.95%), limonene (9.49%), β-myrcene (9.39%), γ-terpinene (9.10%), α-terpinene (8.57%), and 4-terpineol (7.97%).  相似文献   

9.
Pyrolysis of cellulose was studied for the purpose of practical production of 1,6-anhydro-β-D-glucopyranoside (levoglucosan, LG). To minimize secondary degradation of levoglucosan, two methods were examined: (1) conductive heating by glass bottle, and (2) radiation heating from the surface by CO2 laser beam, both under vacuum and in a nitrogen atmosphere. Glass-bottle pyrolysis under vacuum gave levoglucosan yield of 50%–55% in the optimum temperature range of 350°–410°C, where placing the cold trap in the vicinity of heated area was effective in improving the yield. In contrast, glass-bottle pyrolysis under nitrogen gave low yields of 17%–20%, probably due to slower diffusion of pyrolysis product from hot region. The CO2 laser pyrolysis under vacuum gave the product as aerosol (white smoke), causing difficulty in recovery of the product, and the maximum yield was 5%–17%. In this case the treatment under nitrogen flow was effective for recovery of aerosol, and the maximum yield reached approximately 25%.  相似文献   

10.
The purpose of this study was to investigate the sorption of selected volatile substances from oak wood-chip samples (Quercus pyrenaica Willd. and Quercus petraea L.) subjected to different toasting levels, namely, without toasting, with medium toasting, and with strong toasting, through the use of solid-phase microextraction (SPME). The main volatile compounds identified as a function of the toasting level and botanical species were furfural, hexanal, α-pinene, d-limonene, decanal, vitispirane, ethyl hexanoate, cis-3-methyl-γ-octalactone (“oak lactone” or “whisky lactone”), α-terpineol, p-xylene, and nonanal. Considering the data obtained from the toasted woods (medium and strong intensity) in comparison with those of nontoasted woods, it can be pointed out that the average peak area and the number of compounds identified in the gas chromatogram decreased during the toasting process. In general, regarding the compounds analyzed, quantitative differences were found between the two oak wood species under study. High values of volatile compounds were found in Quercus pyrenaica oak wood chips. In addition, for the number of compounds identified in oak wood extracts and directly extracted from solid oak wood chips by SPME, it is concluded that the best extraction process for volatile compounds from oak wood is the use of oak wood-chip liquid extracts.  相似文献   

11.
Variations in the compositions of low boiling point (LBP) monoterpenes in needle samples from 99 sugi (Cryptomeria japonica) and 100 kuromatsu (Pinus thunbergii) trees were investigated using a headspace technique. Considerable variations in the proportions of monoterpenes were revealed in both species. In sugi, the proportions of sabinene and α-pinene in the total LBP monoterpenes, ranging from 8.8% to 73.3% and from 14.5% to 73.3%, respectively, showed enormous variations among nine monoterpenes. The proportions of 3-carene and limonene, ranging from 0.1% to 29.5% and from 0.2% to 20.4%, respectively, also showed very specific variations. In kuromatsu, the proportions of β-pinene and α-pinene in the total LBP monoterpenes, ranging from 26.5% to 66.3% and from 18.7% to 46.9%, respectively, showed considerable variations among ten monoterpenes. The proportions of myrcene and 1,8-cineole, ranging from 0.9% to 18.5% and from 0.8% to 12.3%, respectively, also showed specific variations. Part of this article was presented at the 50th Annual Meeting of the Japan Wood Research Society, Kyoto, April, 2000, and the 13th Annual Meeting of the Chugoku Shikoku Branch of the Japan Wood Research Society, Okayama, September 2001  相似文献   

12.
用挥发油提取器提取马尾松土贡种源松针中挥发油,利用气相色谱-质谱（GC-MS）分析其中的化学成分,采用GC峰面积归一化法定量,并与马尾松普通种源松针油做对比。结果表明,土贡种源和普通种源挥发油得油率分别为0.52％、0.60％,各分出69、75个成分,鉴定其中23个,分别占挥发油总量的92.65％、94.56％,其挥发油主要成分为α-蒎烯（37.673％、46.715％）、莰烯（3.724％、3.015％）、β-蒎烯（14.969％、12.978％）、石竹烯（8.242％、10.212％）,除α-蒎烯含量相差9.042％以外,其他成分含量相差不大。  相似文献   

13.
To determine the suitability of Schima superba Gardn. et Champ as a fuelbreak, we compared and analyzed the flammability characteristics of tree litter from three trees commonly grown in south China, i.e., Pinus massoniana Lamb., Cunninghamia lanceolata (Lamb.) Hook., and S. superba, using a cone calorimeter at five different water content levels. Water content levels of 10%, 15%, 20%, 25% and 30% for the litter were manually produced with a new technique of adding water to dry litter. The cone calorimeter utilized a radiant heat intensity for leaf litter of 20 kW/m2 (510°C) and for twig litter of 30 kW/m2 (608°C). Results show that fixing the water content level by adding water with a pipette was an acceptable technique. For S. superba, compared to P. massoniana and C. lanceolata, 1) the heat release rate (HRR) was slower and lower; 2) the total heat released (THR) from the material was lower and started later in the burning process; and 3) except for the 10% water content, pkHRR/TTI was less. These results show that overall, S. superba was the best of the three species to be used as a fuelbreak in south China. __________ Translated from Scientia Silvae Sinicae, 2008, 44(5): 96–101 [译自: 林 业科学]  相似文献   

14.
This study on the allelopathic effects and chemical components of the essential oi l from Eucalyptus grandis × E. urophylla shows that the leaf oil emulsion of E. grandis × E. urophylla can inhibit the proliferation of pathogenic fungi Fusarium oxysporum, Pyriculerie grisea, Glorosprium musa rum and Phytophthora capsici. Pupation and feeding of the pest insects Spodopteralitura Fabricius and Helicoverpa armigera Hubner are shown to be affected with restraining effects which increase with the increasing levels of oil concentration. A GC/MS analysis of the leaf oil indicated that the main components, with a relative content of ⩾3%, were alloocimene (43.22%), α-pinene (13.63%), γ-terpinene (5.49%), (E)-3,7-dimethyl-2,6-octadien-1-ol (3.58%), β-fenchyl alcohol (4.58%), and 2-amino-3,5-dicyano-6-(4-methoxyphenoxy)-pyridine (3.67%). Terpenes played an important role in the inhibitory effects of E. grandis × E. urophylla essential oil on pathogenic fungi and pest insects. Poor biodiversity of eucalyptus plantations is a function of allelopathy. __________ Translated from Chinese Journal of Ecology, 2007, 26(6): 835–839 [译自: 生态学杂志]  相似文献   

15.
In order to identify the potential of sulfur (S) content in the rings of Masson pine (Pinus massoniana) in the Pearl River Delta as a bio-indicator of regional history of atmospheric pollution, dendrochemistry was used to determine the temporal distribution of S content in the xylem of Masson pines from Zhaoqing Dinghushan and Nanhai Xiqiaoshan, Guangdong Province, southern China. The results indicated that contents of xylem S increased temporally and peaked in the rings formed in the most recent years at both sites. In the rings formed during the same period before the 1980s, S contents were not significantly different between the two sites, while in the rings formed at the same period after the 1980s, S content at Xiqiaoshan were significantly higher than those at Dinghushan. The chronosequences of the S indices at both sites could be easily marked as three periods: before 1970, during 1971–1985, and during 1986–2002. Based on the temporal changes of the xylem S contents and certain social-economic indices after the 1980s in the Delta, the history of atmospheric pollution at the study sites could be reconstructed as follows: 1) before 1970, a period in which the air was relatively clear, 2) 1971–1985, a period in which the air was gradually polluted, and 3) 1986–2002, a period in which the air was most severely polluted in the Delta. __________ Translated from Journal of Beijing Forestry University, 2008, 30(2): 1–7 [译自: 北京林业大学学报]  相似文献   

16.
We surveyed the forest litter amount at the Lianxiahe watershed in the Three Gorges Reservoir Area and analyzed some hydrological characteristics such as the maximum water-holding capacity and water absorption rate of litter in six types of forests, i.e. the Cupressus funebris forest, the coniferous mixed forest, the coniferous and broad-leaved mixed forest, the broad-leaved forest, the Pinus massoniana forest, the bush forest. Results showed that the litter amount follows the order of the coniferous and broad-leaved mixed forest > the pure C. funebris forest, the P. massoniana forest > the coniferous mixed forest > the broad-leaved forest > the bush forest. The maximal water holding capacity of the undecomposed litter is in the order of the C. funebris forest > the coniferous mixed forest > the bush forest > the coniferous and broad-leaved mixed forest > the broad-leaved forest > the P. massoniana forest. The maximal water-holding capacity of the half-decomposed litter is the P. massoniana forest > the coniferous and broad-leaved mixed forest > the C. funebris forest > the coniferous mixed forest > the broad-leaved forest > the bush forest. In this watershed, the water holding capacity of the litter in the C. funebris forest is the highest, followed by the coniferous mixed forest, coniferous and broad-leaved mixed forest, P. massoniana forest, broad-leaved forest and bush forest. When the soil is covered only by litter, both the maximal rainfall amount and intensity in different forest stands are different if there is no water infiltration and runoff from the ground surface. __________ Translated from Journal of Huazhong Agricultural University, 2005, 27(2): 207–212 [译自: 华中农业大学学报, 2005, 24(2): 207–212]  相似文献   

17.
[目的]为了丰富马尾松遗传信息,开发更多适用于马尾松的新型分子标记。[方法]依据马尾松Ty1-copia类型和Ty3-gypsy类型反转录转座子RT序列的保守区域设计引物,建立了马尾松IRAP-PCR技术体系并以12个基因型个体为材料进行验证。[结果]42条引物中筛选出多态性丰富、重复性好的29条进行PCR扩增,共获得227条谱带,其中多态性条带207个,多态性比例为91.19%,平均观测等位基因数(Na)为1.911 9±0.284 1,有效等位基因数(Ne)为1.468 0±0.288 2,Nei’s基因多样性指数(H)为0.291 1±0.144 9,Shannon’s信息指数(I)为0.447 2±0.195 3;利用引物P-12、P-15或R-1,可以将栽培种与无性系两类区分开;P-2可作为核心引物,能将12份供试材料有效区分开来;采用IRAP标记构建了供试种质的DNA指纹图谱;供试种质的遗传相似系数为0.46 0.69,以相似系数为基础,进行UPGMA聚类分析,以0.57为阈值可将供试种质分为三类,其中无性系内不同材料间也存在较大的遗传变异。[结论]IRAP分子标记能有效地用于马尾松种质的鉴别与亲缘关系分析等相关研究。  相似文献   

18.
In order to provide a basis for water conservation in the restoration of vegetation for an urban water resource area, we studied the generation of runoff characteristics in four typical forests over three time periods in Jinyun Mountain, Chongqing City, based on the observation data of rainfall and runoff processes during the period 2002–2005. The results show that: 1) Rainfall was distributed evenly during the years 2002–2005. Annual rainfall variability was 4.46% and coefficient of variation was 0.0618. Average monthly rainfall tended towards a normal distribution N (113.8, 45972). 2) Both precipitation and runoff can be clearly divided into a dry and a wet season. The dry season was from October to March and the wet season from April to September. Most of annual runoff of the four forest stands occurred in the wet season. The surface runoff in the wet season accounted for more than 85% of the annual runoff, and more than 75% of underground runoff. 3) Both peak values of surface runoff and underground runoff occurred in June. The relation between monthly rainfall and surface/underground runoff was fitted by the model W=aP 2 + bP + c. The order of annual surface runoff was as follows: Phyllostachys pubescens forest > shrub forest > mixed Pinus massoniana-broadleaf forest > evergreen broad-leaved forest. The annual underground runoff was evergreen broad-leaved forest > mixed Pinus massoniana-broadleaf forest > Phyllostachys pubescens forest > shrub forest. 4) Under similar rainstorms events, the order of the surface runoff coefficient was: evergreen broad-leaved forest < mixed Pinus massoniana-broadleaf forest < shrub forest < Phyllostachys pubescens forest. The underground runoff coefficient was: evergreen broad-leaved forest > mixed Pinus massoniana-broadleaf forest > Phyllostachys pubescens forest > shrub forest. The relation between rainstorms and surface runoff was fitted by the linear relationship: Q = mp − n. Both mixed Pinus massoniana-broadleaf forest and evergreen broad-leaved forest have better flood regulation effects on an annual and monthly basis and per individual rainstorm. The function of Phyllostachys pubescens forest is the worst on all three bases. __________ Translated from Journal of Beijing Forestry University, 2008, 30(4): 103–108 [译自: 北京林业大学学报]  相似文献   

19.
Vegetation restoration is a key measure to improve the eco-environment in Loess Plateau, China. In order to find the effect of soil microbial biomass under different vegetation restoration models in this region, six trial sites located in Zhifanggou watershed were selected in this study. Results showed that soil microbial biomass, microbial respiration and physical and chemical properties increased apparently. After 30 years of vegetation restoration, soil microbial biomass C, N, P (SMBC, SMBN, SMBP) and microbial respiration, increased by 109.01%–144.22%, 34.17%–117.09%, 31.79%–79.94% and 26.78%–87.59% respectively, as compared with the farmland. However, metabolic quotient declined dramatically by 57.45%–77.49%. Effects of different models of vegetation restoration are different on improving the properties of soil. In general, mixed stands of Pinus tabulaeformis-Amorpha fruticosa and Robinia pseudoacacia-A. fruticosa had the most remarkable effect, followed by R. pseudoacacia and Caragana korshinkii, fallow land and P. tabulaeformis was the lowest. Restoration of mixed forest had greater effective than pure forest in eroded Hilly Loess Plateau. The significant relationships were observed among SMBC, SMBP, microbial respiration, and physical and chemical properties of soil. It was concluded that microbial biomass can be used as indicators of soil quality. __________ Translated from Journal of Natural Resources, 2007, 22(1): 20–27 [译自: 自然资源学报]  相似文献   

20.
In this study, solid-phase micro-extraction (SPME) fibers coated with polydimethylsiloxane/divinylbenzene (PDMS/DVB), coupled with gas chromatography/mass spectrometry, were used to monitor the emission patterns of biogenic volatile organic compounds (BVOCs) from leaves of Calocedrus macrolepis var. formosana Florin. in situ. In both sunny and rainy weather, the circadian profile for BVOCs from C. macrolepis var. formosana leaves has three maximum emission cycles each day. This kind of emission pattern might result from the plant’s circadian clock, which determines the rhythm of terpenoid emission. Furthermore, emission results from the leaves demonstrated that the circadian profile of α-pinene observed was opposite to the profiles of limonene and myrcene, a difference that may be attributable to two different subpathways for terpenoid biosynthesis.  相似文献   

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