With the guidance of Erikson’s identity theory,the article analyzes the clones’identity exploration through role identification in Never Let Me Go.It interprets the clones’puzzlement about their identity,and the pr...With the guidance of Erikson’s identity theory,the article analyzes the clones’identity exploration through role identification in Never Let Me Go.It interprets the clones’puzzlement about their identity,and the process of their identity quest as well as role identification.Through the specific analysis,it is concluded that the clones,represented by Kathy,Tommy and Ruth,have gained self-certainty and social identity by realizing the role identity as a“carer”and a“donor”,in the meantime,they have constructed their identity as social persons with souls like ordinary people.Furthermore,the findings shows that Never Let Me Go is actually a microcosm of human’s quest for identity.Ishiguro aims to express his meditation on human life in the novel:human life is a process of seeking self-identity and social roles,and then fulfilling the obligations of the roles,which confirms Ishiguro’s internationalism that he attempts to convey his contemplation on human existence through his works.展开更多
Japanese British writer Kazuo Ishiguro is one of the leading writers in contemporary British literature.He has always been committed to creating works with universal significance.Responsibility and destiny are themes ...Japanese British writer Kazuo Ishiguro is one of the leading writers in contemporary British literature.He has always been committed to creating works with universal significance.Responsibility and destiny are themes that run through his works.His novel Never Let Me Go tells a story of a group of clones growing up in the Hailsham,who are given the mission to donate organs at birth.So,there is no doubt that they will inevitably end their lives in the process of donating organs to human beings again and again.The tragic life of clones is determined by the motivation of human to create them.展开更多
[Objective] The experiment was aimed to select effective and economical media for container seedling of triploid clones of Populus tomentosa that was carried out. [Method] The sandy loam, peat, perlite, vermiculite, r...[Objective] The experiment was aimed to select effective and economical media for container seedling of triploid clones of Populus tomentosa that was carried out. [Method] The sandy loam, peat, perlite, vermiculite, riversand, sludge were taken as media of hardwood cutting and survival rate, seedling height were taken as indexes to select media for container seedling of triploid clones of Populus tomentosa. [Result] Different mixedmedia had great influence on survival rates of container seedlings. Taking peat and vermiculite with the proportion of 5∶2 (M10) or peat ,vermiculite with the proportion of 7∶2 (M11) or sandy loam (M1) as media would generate higher cutting survival rate that was higher than 90.0%. There were significant differece in height increments of container seedlings. Taking sandy loam, peat and vermiculite with the proportion of 6∶2∶2(M5)or sandy loam (M1), seedling height of 60-days the seedling was over 37.0 cm. [Conclusion] According to cost analysis of nursery medium, the optimum medium for hardwood cuttings container seedling-raising of triploid clones of Populus tomentosa was sandy loam.展开更多
[Objective] This study aimed to investigate the effects of drought stress on osmotic regulation substances of Catalpa bungei clones. [Method] Potting experimental was carried out with plastic film sealing method, to d...[Objective] This study aimed to investigate the effects of drought stress on osmotic regulation substances of Catalpa bungei clones. [Method] Potting experimental was carried out with plastic film sealing method, to differentiate the degrees of drought stress based on changes in soil water content and leaf water potential and investigate variations in contents of osmotic regulation substances(free proline,soluble sugar and soluble protein) in leaves of five Catalpa bungei clones under different degrees of drought stresses. [Result] According to changes in soil water content and leaf water potential, the whole process of drought stress was divided into normal level(CK, with soil water content of 97.49% and leaf water potential of-0.54MPa), light drought(LD with soil water content of 59.96% and leaf water potential of-1.28 MPa), mediate drought(MD with soil water content of 34.19% and leaf water potential of-2.32 MPa) and severe drought(SD with soil water content of 14.52%and leaf water potential of-2.99 MPa). The soil water content and leaf water potential of five Catalpa bungei clones reached the highest correlation in exponential fitting, with an average R2of 0.989 3(P0.001). The free proline content in leaves of five Catalpa bungei clones increased rapidly with the increasing degree of drought stress(P 0.001). To be specific, free proline contents of Catalpa bungei clones015-1 and 7080 were 34.39 and 33.41 times of the normal level under severe drought conditions, which reached an extremely significant level(P0.001); the free proline content of Catalpa bungei clone 1-3 rapidly increased to(855.46±227.52) μg/g Fw under light drought conditions. The soluble protein content in leaves showed different variation trends. To be specific, the soluble protein content of Catalpa bungei clone 7080 was the lowest at various drought stages and reached(1.644 ±0.137)mg/g Fw under normal conditions; the soluble protein content of Catalpa bungei clone 1-3 was relatively high under normal conditions and was reduced rapidly under light drought conditions, showing different response patterns. [Conclusion] Osmotic regulation substances in leaves of five Catalpa bungei clones all have certain response to drought stress. Free proline is the most important osmotic regulation substance, followed by soluble protein, while soluble sugar makes no significant contribution. According to changes in content of osmotic regulation substances, Catalpa bungei clone 7080 has relatively high capacity and good drought resistance, while Catalpa bungei clone 1-3 has the rapidest response to drought stress.展开更多
Cutting propagation rhizogenesis of Toona ciliata clone cutting orchard were studied, and the results were as fol ows: Rooting type included both cal us rooting and cortex rooting. About 17 in 22 of clones were domin...Cutting propagation rhizogenesis of Toona ciliata clone cutting orchard were studied, and the results were as fol ows: Rooting type included both cal us rooting and cortex rooting. About 17 in 22 of clones were dominated by cortex rooting, accounting for the 77% of clones. There were 5 clones which occurred with both cal us rooting and cortex rooting during rooting process. The rooting efficiency index (REI) showed a positive correlation with the rooting rate. Under natural tem-perature condition, keeping moisture and shading, we found that the highest survival rate occurred in early June, September, and October.展开更多
The wood samples of 9 triploid clones of Populus tomentosa Carr. taken from a 9 year old clonal test site were analyzed in order to investigate the genetic variation of wood properties, including air dried wood...The wood samples of 9 triploid clones of Populus tomentosa Carr. taken from a 9 year old clonal test site were analyzed in order to investigate the genetic variation of wood properties, including air dried wood density and some mechanical properties. The results showed that significant or extremely significant difference in air dried wood density and the mechanical properties existed among the clones, this means these wood properties were under moderate or strong genetic controls and could be improved by genetic manipulations. The radial and vertical variation patterns of air dried wood density were also studied and the results were found to coordinate with other previous research results. The vertical variation patterns of most mechanical properties within the individual tree also conformed to the general wood theories except the modulus of elasticity and cross section hardness. Among the mechanical properties, modulus of elasticity (MOE) and tangent section hardness were under strong genetic control, with the clonal repeatabilities being 0 90 and 0 80, respectively. However, the clonal repeatabilities of other mechanical properties under study were a little lower than above two indexes. Genetic correlation analysis indicated that super clonal selection and breeding for veneer timber could be realized through indirect selection of wood density and form indexes.展开更多
The oxygen evolution, thermal dissipation, and photochemical energy storage of three hybrid poplar clones, namely the triploid clone B342, the diploid clone B11 [(Populus alba×P. glandulosa)×(P.tomentosa...The oxygen evolution, thermal dissipation, and photochemical energy storage of three hybrid poplar clones, namely the triploid clone B342, the diploid clone B11 [(Populus alba×P. glandulosa)×(P.tomentosa×P.bolleana)], and the triploid clone B346 [(P.tomentosa×P. bolleana)×(P. alba×P.glandulosa)], under light stress were studied using photoacoustics. The oxygen evolution signal and photochemical energy storage varied negatively with the pretreatment_PFD (photon flux density), whereas the thermal signal varied positively with the pretreatment_PFD. Photochemical energy storage was reallocated to PSⅡ more than to PSⅠ, while the photochemical energy storage in PSⅠ was more stable than that in PSⅡ when subjected to light stress. The inhibitors streptomycin (SM), dithiothreitol (DTT) and sodium fluoride (NaF) could all affect the oxygen evolution signal. Clones B11 and B342 were more resistant to light stress than clone B346.展开更多
In order to provide directionally genetically improved breeding materials of poplar by exploring the phenological traits genetic variation level and its develop- ment potential of Populus deltoides and the resource ev...In order to provide directionally genetically improved breeding materials of poplar by exploring the phenological traits genetic variation level and its develop- ment potential of Populus deltoides and the resource evaluation was carried out; 8 phenological phases in seedling period were observed and analyzed of 60 Populus deltoids clones introduced from America. The results showed that: (1) there was obvious difference in phonological character among clones, especially in leaf-spread- ing peak stage and the end term of leaf-falling stage, with the largest variation co- efficient of 14.97% and the minimum of 3.83% respectively. (2) Leaf-spreading peak stage scattered but the end term of leaf-falling stage concentrated the most. The phonological character in early stage of seedling growth was the main factor influ- encing the length of growing season. (3) By principal component analysis, pheno- logical phases were classified into 3 typical periods, including germination stage, leaf-spreading peak stage and leaf-falling stage. (4) Totaling 60 clones were classi- fied into 4 types by using clustering analysis in phenological time variables of clones.展开更多
[Objective] This study aimed to provide scientific basis for the early selec-tion and breeding of excellent Catalpa bungei clones. [Method] The Li-6400 portable photosynthesis system was used to analyze the photosynth...[Objective] This study aimed to provide scientific basis for the early selec-tion and breeding of excellent Catalpa bungei clones. [Method] The Li-6400 portable photosynthesis system was used to analyze the photosynthetic characteristics of five Catalpa bungei clones (1-3, 1-4, 004-1, 015-1 and 7080). [Result] Al five Catalpa bungei clones had similar change trends of light response curves, but their maxi-mum net photosynthetic rates (Pmax) were in the order of 1-3>7080>015-1>004-1>1-4, showing that clone 1-3 and clone 7080 had strong light environmental adapt-ability with the light saturation points (LSP) of 1 147.97 μmol/m2·s and 1 196.31μmol/m2·s, respectively, while clone 1-4 had the narrowest range of adaptation to light. There were differences in the total photosynthetic amount per area among the five clones that clone 1-4 was the best of 433 974.24 μmol/m2, fol owed by clone 1-3 of 401 290.20 μmol/m2. The transpiration rates (Tr) and stomatal conductances (Cond) of the five clones presented the same change trend. And the diurnal varia-tion curves of net photosynthetic rate (Pn) of clone 1-3, 1-4 and 015-1 showed two typical peaks with obvious midday depression, while clone 004-1 and 7080 didn’t. [Concluson] Considering a variety of photosynthetic characteristics of indica-tors, photosynthetic capacity of clone 1-3 was the best among the five Catalpa bungei clones.展开更多
We studied the genetic polymorphism among 29 clones of shisham (Dalbergia sissoo Roxb) belonging to different geographic regions using random amplified polymorphic DNA (RAPD) markers. Out of 30 primers used, only ...We studied the genetic polymorphism among 29 clones of shisham (Dalbergia sissoo Roxb) belonging to different geographic regions using random amplified polymorphic DNA (RAPD) markers. Out of 30 primers used, only 20 primers generated polymorphism in amplified product. In total 232 bands were amplified with 20 primers, of which 192 (82%) were polymorphic with an average of 9.6 bands/primer. The resolving power (Rp) ranged from 2.14 (Primer 5) to 11.93 (Primer 4). Primer 4 and Primer 3 possessed high Rp value. Polymorphism information content (PIC) ranged from 0.15 (Primer 5) to 0.37 (Primer 4). Primer 4 amplified total 18 bands in 29 genotypes with PIC value of 0.37 hence; this set of primer was most informative. The similarity coefficient analysis revealed two clusters. The first cluster comprised of only 10 clones and the second major cluster comprised of 19 clones. The genetic similarity among 29 clones ranged from 25.86% (clone 10 and 235) to 100% (clone 19 and 59), suggesting a wide genetic base in shisham clones.展开更多
It is very important to select and identify superior Xanthoceras sorbifolia Bge. trees for purposes of breeding and exploration. For our study, we selected superior X. sorbifolia trees using RAPD (random amplificatio...It is very important to select and identify superior Xanthoceras sorbifolia Bge. trees for purposes of breeding and exploration. For our study, we selected superior X. sorbifolia trees using RAPD (random amplification of polymorphic DNA) technology. The results show that certain specific amplification bands emerged with significantly different frequencies between superior and non-superior trees. The 1400-bp band of No. 2121 primer emerged in the superior trees at a frequency 2.4 times that of the non-superior trees and the 600-bp band of No. 2153 primer in the non-superior trees at a frequency 2.5 times that of the superior trees There were very significant differences between the superior and non-superior trees. The frequency of the 1600-bp band of No. 1161 primer was the same in both kinds of trees, but significant differences were observed in point frequency (the frequency of the superior trees is 1,4 times that of the non-superior trees). These bands can be used as important targets to distinguish between superior and non-superior trees. The use of a combination of amplified bands simultaneously can play a guiding role in the selection of superior X. sorbifolia trees.展开更多
Eucalyptus has become an important genus in China because it displays adaptability to a wide range of site conditions and produces pulp wood and veneer on short rotations. The aim of this study was to estimate genetic...Eucalyptus has become an important genus in China because it displays adaptability to a wide range of site conditions and produces pulp wood and veneer on short rotations. The aim of this study was to estimate genetic parameters and relationships and consider impli- cations for development of clonal forestry. We assessed growth traits, stem-branch characteristics, crown diameter and height of fresh branch for 20 Eucalyptus hybrid clones in China measured at the age of 44 months. Analysis of variance showed that there were significant differences in growth traits, height of fresh branch and stem straightness among clones. Significant differences in height, volume, crown diameter, height of fresh branch and branch size among replicates were also recorded. Coefficients of vari- ation ranged from 9.84 to 28.54 % for growth traits, 12.03 to 17.25 % for stem-branch characteristics, 18.26 % for crown diameter and 11.73 % for height of fresh branch. Estimates of repeatabilities for height, diameter at breastheight over bark, volume, crown diameter, height of fresh branch, stem straightness and branch size at clone mean level were 0.86, 0.80, 0.80, 0.54, 0.85, 0.77 and 0.44 respectively. Diameter at breast height over bark and height had strongly positive phenotypic and genotypic correlations with volume, ranging from 0.96 to 1.00. The positive genotypic and phenotypic correlations between growth traits and other studied traits suggested that fast growing clones always had bigger crown diameter, higher height of fresh branch, straighter stems and relatively smaller branches.展开更多
Fifty-three larch interspecific hybrid clones(Larix kaempferi × L.gmelini) and their parent clones were used for growth curve analysis of height variations.The growth curves of the 55 clones were 'S'-shaped a...Fifty-three larch interspecific hybrid clones(Larix kaempferi × L.gmelini) and their parent clones were used for growth curve analysis of height variations.The growth curves of the 55 clones were 'S'-shaped and 36 exhibited similar curves as the male parent.The coefficients of the logistic models were higher than 0.943,indicating that our results were effective in the simulation of the growth curves.ANOVA analysis showed significant differences in height of different clones (P/0.01).Average date of maximum height growth was Day 173,and average duration of rapid growth lasted for 50 days.Annual average increase in height was 9.7cm d^(-1) and daily average increase was 0.2 cm.The ratio of GR to the total annual increase in height ranged from 51.2 to 68.8%,with the average being 59.8%.There was a positive correlation between k values and plant heights which benefited from the evaluation of early plant height.There was also a positive correlation between GR(growth stage),GD(plant height) and annual increase in height.These results are informative to the evaluation of the elite clone selection and provide a theoretical basis for breeding and management.展开更多
In order to understand the structural characteristics of lignin in triploid clones ofPopulus tomentosa and its changes in the processes of pulping and bleaching, milled wood lignin (MWL), lignin carbohydrate complex...In order to understand the structural characteristics of lignin in triploid clones ofPopulus tomentosa and its changes in the processes of pulping and bleaching, milled wood lignin (MWL), lignin carbohydrate complex (LCC) and the residual lignin from kraft pulp (KP) and sulfite pulp (SP) were isolated and analyzed by Fourier transform infrared (FTIR) spectrum and ^13C nuclear magnetic resonance (NMR). The most diagnostic peaks were assigned and the differences were discussed. The spectral patterns reveal that triploid P tomentosa shows the specific features of hardwood from temperate areas, but in the spectrum of FTIR, the strength ratio orAl270 cm^-1 to A1226 cm^-1 is 0.88, higher than the average of hardwood from temperate areas, which will make the lignin delignification more difficult during pulping and bleaching. The LCC from triploid P tomentosa is mainly composed of xyloglucan and glucuronic acid, and other glucides have much lower ratio. In LCC FTIR, there are three peaks at 1 427, 1 329 and 1 046 cm^-1, indicating that both semi-cellulose and cellulose could exist in LCC, and that there might be relationships between cellulose and lignin. Compared with the residual lignin from KP and SP, the condensed structure in KP is more than that in SP.展开更多
[Objective] The aim was to study the effects of drought stress on contents of endogenous hormones in leaves of different clones of Liriodendron chinense×L. tulipifera. Drought-resistant Liriodendron chinense×...[Objective] The aim was to study the effects of drought stress on contents of endogenous hormones in leaves of different clones of Liriodendron chinense×L. tulipifera. Drought-resistant Liriodendron chinense×L. tulipifera clones NE25,NE78 and drought-sensitive Liriodendron chinense×L. tulipifera clones NE04,NE23 were selected as experimental materials to study the content changes of four kinds of endogenous hormones such as abscisic acid (ABA),indoleacetic acid (IAA),ribosylzeatin (ZR) and jasmonic acid (JA) in leaves of different clones under drought stress. [Result] Under drought stress,ABA was accumulated I leaves of different clones,however,the content changes in drought-resistant clones were not obvious; IAA content showed a decreasing trend,and the content changes n drought-resistant clones during later period of drought stress was decreased; JA content showed an increasing trend in leaves of drought-sensitive clones,indicating that drought-sensitive clones had to maintain higher contents of JA to resist drought stress. [Conclusion] The result of this study had provided scientific basis for the screening,planting and application of drougt-resistant clones of Liriodendron chinense×L. tulipifera.展开更多
Teak(Tectona grandis Linn. f.), one of the mostvalued tree species in the world, is slow-growing with a long period until it can be harvested;therefore, ensuring that only high-quality seedlings or clones are selected...Teak(Tectona grandis Linn. f.), one of the mostvalued tree species in the world, is slow-growing with a long period until it can be harvested;therefore, ensuring that only high-quality seedlings or clones are selected for planting is critical. The main objective was to determine performance and repeatability of selected clones in terms of growth and survival rates in different micro-environments. A 2-year clonal trial using 41 clones and a local seedling of teak as a control were grown at 4 microsites differing in spacing, soil fertility and alley crops to assess tree height, diameter and survival rate that was evaluated in Purwakarta, West Java, Indonesia using a randomized complete block design with four replicates of each clone at each microsite. Teak growth was influenced by clone(p < 0.01), microsite(p < 0.05) and clone 9 micrositeinteraction(p<0.01). The interaction clone 9 microsite resulted in several potential superior clones that differed in terms of growth rates at each microsite. On the basis of diameter only, superior clones(nos. 14, 18, 24, 30 and 37)were identified. Repeatability estimated was Rc2= 0.84 for diameter and Rc2= 0.77 for height. Growth performance of teak trees varied among microsites. Repeatability values for diameter and height characters were high. The effect of variable growth on each clone was influenced by genetic factors, environmental factors and the interaction of genetics 9 environment. Microsite significantly affected growth of teak clones. Clone 9 microsite interaction significantly affected growth of clones and led to the growth of superior clones at each microsite.展开更多
Random Amplified Polymorphic DNA (RAPD) polymor- phism was employed to assess the genetic diversity in the elite germplasm'of Dalbergia sissoo. Sixty-seven clones that are under cultivation in northern India, origi...Random Amplified Polymorphic DNA (RAPD) polymor- phism was employed to assess the genetic diversity in the elite germplasm'of Dalbergia sissoo. Sixty-seven clones that are under cultivation in northern India, originated frorri six different states of India and Nepal were analyzed with 30 RAPD primers that generated a total of 342 fragments out of which 290 were polymorphic. Total genetic diversity (Ht) varied between 0.01 and 0.37, with an average of 0.19. Shannon's Information index (I) varied between 0102 and 0.54, with an average of 0.31. Marker attributes like Polymorphism Information Content (PIC), Marker Index (MI) and Effective Multiplex Ratio (EMR) values were calculated to assess the discriminatory power of 30 primers used. The PIC values ranged from 0.01 to 0.37 with an average of 0.17 per primer and the EMR ranged from 0.17 to 21.00 with a mean of 8.66 across all genotypes. Closely related clones were C49 and C51 with similarity index of 0.86 while the least similar or most dissimilar clones were C14 and S-DB showing similarity index of 0.58. The UPGMA-phenogram categorized the 67 clones into six clusters based on genetic similarity and dissimilarity. The clustering of clones in relation to their geographical location has been discussed.展开更多
Ten microsatellite markers were used to analyze the levels of genetic diversity and inbreeding in a hatchery release population of Rhopilema esculentum Kishinouye (Scypbozoa: Rhizostomatidae). A total of 85 alleles...Ten microsatellite markers were used to analyze the levels of genetic diversity and inbreeding in a hatchery release population of Rhopilema esculentum Kishinouye (Scypbozoa: Rhizostomatidae). A total of 85 alleles were detected in 600 individuals. Within-population levels of observed (Ho) and expected (He) heterozygosity ranged from 0.152 to 0.839 (mean=0.464) and from 0.235 to 0.821 (mean=0.618), respectively. The polymorphism information content (PIC) of each marker ranged from 0.207 to 0.795 with an average of 0.580, indicating that the hatchery population maintained a high level of genetic diversity. Inbreeding levels were estimated in the hatchery population and the inbreeding coefficient was 0.203. This result revealed that a certain level of inbreeding occurred within the population. Meanwhile, we also determined genetic diversity at the clone level. Several polyps from the same scyphistomae were genotyped at the ten microsatellite loci and there was virtually no difference in their genotypes. Furthermore, we calculated the probabilities of exclusion. When both parents were known, the average exclusion probability often loci was 99.99%. Our data suggest that the ten microsatellite markers can not only be used to analyze the identity of individuals but they can also be applied to parentage identification. Our research provides a theoretical basis and technical support for genetic diversity detection and reasonable selection of R. esculentum hatchery populations. These findings support the use of releasing studies and conservation of R. esculentum germplasm resources.展开更多
Poplar leaf defoliator, Clostera fulgurita (Walker) larvae were reared on three Populus deltoides clones (PL1, PL5 and PL7) in the laboratory. The nutritional indices were computed for working out the relationship...Poplar leaf defoliator, Clostera fulgurita (Walker) larvae were reared on three Populus deltoides clones (PL1, PL5 and PL7) in the laboratory. The nutritional indices were computed for working out the relationship between food consumption and growth rate of 3rd, 4th and 5th instar larvae on three clones. The result showed that the consumption index (CI), approximate digestibility (AD), growth rate (GR), relative growth rate (RGR) and efficiency of conversion of ingested food (ECI) decreased with the increase in the age of the larvae. Efficiency of conversion of digested food (ECD) increased with increase in age of the larvae. GR and RGR varied significantly, indicating that larval development was enhanced on PL1 as compared to PL5 & PL7. The values of AD, ECI and ECD were not affected by the different clones. Feeding and growth indices could be useful to define a defoliation prediction model.展开更多
With four poplar clones, namely 84-323 (Populus deltoides cv. ?4-323?, 84-324 (Populus deltoides cv. ?4-324?, 79-35 (Populus ?euramericana cv. ?9-35?, and I-69 (Populus deltoides cv. 慙ux?I-69/55) as a control, resear...With four poplar clones, namely 84-323 (Populus deltoides cv. ?4-323?, 84-324 (Populus deltoides cv. ?4-324?, 79-35 (Populus ?euramericana cv. ?9-35?, and I-69 (Populus deltoides cv. 慙ux?I-69/55) as a control, researches on cold, drought and salt resistance of the clones were conducted. Electrolyte permeability under a series of low temperatures, relative water loss rate of detached leaves with time series and survival rate and growth performance in salt soil were measured. The results showed that 84-323, 84-324 and 79-35 were resistant to cold as same as I-69 (CK) and more resistant to drought and salinity than I-69 (CK).展开更多
文摘With the guidance of Erikson’s identity theory,the article analyzes the clones’identity exploration through role identification in Never Let Me Go.It interprets the clones’puzzlement about their identity,and the process of their identity quest as well as role identification.Through the specific analysis,it is concluded that the clones,represented by Kathy,Tommy and Ruth,have gained self-certainty and social identity by realizing the role identity as a“carer”and a“donor”,in the meantime,they have constructed their identity as social persons with souls like ordinary people.Furthermore,the findings shows that Never Let Me Go is actually a microcosm of human’s quest for identity.Ishiguro aims to express his meditation on human life in the novel:human life is a process of seeking self-identity and social roles,and then fulfilling the obligations of the roles,which confirms Ishiguro’s internationalism that he attempts to convey his contemplation on human existence through his works.
文摘Japanese British writer Kazuo Ishiguro is one of the leading writers in contemporary British literature.He has always been committed to creating works with universal significance.Responsibility and destiny are themes that run through his works.His novel Never Let Me Go tells a story of a group of clones growing up in the Hailsham,who are given the mission to donate organs at birth.So,there is no doubt that they will inevitably end their lives in the process of donating organs to human beings again and again.The tragic life of clones is determined by the motivation of human to create them.
基金Supported by National Key Technology R&D Program during the 11th Five-year Plan Period(2006BAD32B01)~~
文摘[Objective] The experiment was aimed to select effective and economical media for container seedling of triploid clones of Populus tomentosa that was carried out. [Method] The sandy loam, peat, perlite, vermiculite, riversand, sludge were taken as media of hardwood cutting and survival rate, seedling height were taken as indexes to select media for container seedling of triploid clones of Populus tomentosa. [Result] Different mixedmedia had great influence on survival rates of container seedlings. Taking peat and vermiculite with the proportion of 5∶2 (M10) or peat ,vermiculite with the proportion of 7∶2 (M11) or sandy loam (M1) as media would generate higher cutting survival rate that was higher than 90.0%. There were significant differece in height increments of container seedlings. Taking sandy loam, peat and vermiculite with the proportion of 6∶2∶2(M5)or sandy loam (M1), seedling height of 60-days the seedling was over 37.0 cm. [Conclusion] According to cost analysis of nursery medium, the optimum medium for hardwood cuttings container seedling-raising of triploid clones of Populus tomentosa was sandy loam.
基金Supported by National Scientific and Technological Project in Rural Areas in the "Twelfth Five Year" Plan(2012BAD21B03,2012BAD21B0304)~~
文摘[Objective] This study aimed to investigate the effects of drought stress on osmotic regulation substances of Catalpa bungei clones. [Method] Potting experimental was carried out with plastic film sealing method, to differentiate the degrees of drought stress based on changes in soil water content and leaf water potential and investigate variations in contents of osmotic regulation substances(free proline,soluble sugar and soluble protein) in leaves of five Catalpa bungei clones under different degrees of drought stresses. [Result] According to changes in soil water content and leaf water potential, the whole process of drought stress was divided into normal level(CK, with soil water content of 97.49% and leaf water potential of-0.54MPa), light drought(LD with soil water content of 59.96% and leaf water potential of-1.28 MPa), mediate drought(MD with soil water content of 34.19% and leaf water potential of-2.32 MPa) and severe drought(SD with soil water content of 14.52%and leaf water potential of-2.99 MPa). The soil water content and leaf water potential of five Catalpa bungei clones reached the highest correlation in exponential fitting, with an average R2of 0.989 3(P0.001). The free proline content in leaves of five Catalpa bungei clones increased rapidly with the increasing degree of drought stress(P 0.001). To be specific, free proline contents of Catalpa bungei clones015-1 and 7080 were 34.39 and 33.41 times of the normal level under severe drought conditions, which reached an extremely significant level(P0.001); the free proline content of Catalpa bungei clone 1-3 rapidly increased to(855.46±227.52) μg/g Fw under light drought conditions. The soluble protein content in leaves showed different variation trends. To be specific, the soluble protein content of Catalpa bungei clone 7080 was the lowest at various drought stages and reached(1.644 ±0.137)mg/g Fw under normal conditions; the soluble protein content of Catalpa bungei clone 1-3 was relatively high under normal conditions and was reduced rapidly under light drought conditions, showing different response patterns. [Conclusion] Osmotic regulation substances in leaves of five Catalpa bungei clones all have certain response to drought stress. Free proline is the most important osmotic regulation substance, followed by soluble protein, while soluble sugar makes no significant contribution. According to changes in content of osmotic regulation substances, Catalpa bungei clone 7080 has relatively high capacity and good drought resistance, while Catalpa bungei clone 1-3 has the rapidest response to drought stress.
基金Supported by Hunan Forestry Science and Technology Project(XLK201406)~~
文摘Cutting propagation rhizogenesis of Toona ciliata clone cutting orchard were studied, and the results were as fol ows: Rooting type included both cal us rooting and cortex rooting. About 17 in 22 of clones were dominated by cortex rooting, accounting for the 77% of clones. There were 5 clones which occurred with both cal us rooting and cortex rooting during rooting process. The rooting efficiency index (REI) showed a positive correlation with the rooting rate. Under natural tem-perature condition, keeping moisture and shading, we found that the highest survival rate occurred in early June, September, and October.
文摘The wood samples of 9 triploid clones of Populus tomentosa Carr. taken from a 9 year old clonal test site were analyzed in order to investigate the genetic variation of wood properties, including air dried wood density and some mechanical properties. The results showed that significant or extremely significant difference in air dried wood density and the mechanical properties existed among the clones, this means these wood properties were under moderate or strong genetic controls and could be improved by genetic manipulations. The radial and vertical variation patterns of air dried wood density were also studied and the results were found to coordinate with other previous research results. The vertical variation patterns of most mechanical properties within the individual tree also conformed to the general wood theories except the modulus of elasticity and cross section hardness. Among the mechanical properties, modulus of elasticity (MOE) and tangent section hardness were under strong genetic control, with the clonal repeatabilities being 0 90 and 0 80, respectively. However, the clonal repeatabilities of other mechanical properties under study were a little lower than above two indexes. Genetic correlation analysis indicated that super clonal selection and breeding for veneer timber could be realized through indirect selection of wood density and form indexes.
文摘The oxygen evolution, thermal dissipation, and photochemical energy storage of three hybrid poplar clones, namely the triploid clone B342, the diploid clone B11 [(Populus alba×P. glandulosa)×(P.tomentosa×P.bolleana)], and the triploid clone B346 [(P.tomentosa×P. bolleana)×(P. alba×P.glandulosa)], under light stress were studied using photoacoustics. The oxygen evolution signal and photochemical energy storage varied negatively with the pretreatment_PFD (photon flux density), whereas the thermal signal varied positively with the pretreatment_PFD. Photochemical energy storage was reallocated to PSⅡ more than to PSⅠ, while the photochemical energy storage in PSⅠ was more stable than that in PSⅡ when subjected to light stress. The inhibitors streptomycin (SM), dithiothreitol (DTT) and sodium fluoride (NaF) could all affect the oxygen evolution signal. Clones B11 and B342 were more resistant to light stress than clone B346.
基金Supported by National Special Funds for Forest Research in the Public Interest(201004004)~~
文摘In order to provide directionally genetically improved breeding materials of poplar by exploring the phenological traits genetic variation level and its develop- ment potential of Populus deltoides and the resource evaluation was carried out; 8 phenological phases in seedling period were observed and analyzed of 60 Populus deltoids clones introduced from America. The results showed that: (1) there was obvious difference in phonological character among clones, especially in leaf-spread- ing peak stage and the end term of leaf-falling stage, with the largest variation co- efficient of 14.97% and the minimum of 3.83% respectively. (2) Leaf-spreading peak stage scattered but the end term of leaf-falling stage concentrated the most. The phonological character in early stage of seedling growth was the main factor influ- encing the length of growing season. (3) By principal component analysis, pheno- logical phases were classified into 3 typical periods, including germination stage, leaf-spreading peak stage and leaf-falling stage. (4) Totaling 60 clones were classi- fied into 4 types by using clustering analysis in phenological time variables of clones.
基金Supported by the National Key Technology R&D Program(2012BAD21B03)Specialized Research Fund for The Doctoral Program of Higher Education(20124404120008)~~
文摘[Objective] This study aimed to provide scientific basis for the early selec-tion and breeding of excellent Catalpa bungei clones. [Method] The Li-6400 portable photosynthesis system was used to analyze the photosynthetic characteristics of five Catalpa bungei clones (1-3, 1-4, 004-1, 015-1 and 7080). [Result] Al five Catalpa bungei clones had similar change trends of light response curves, but their maxi-mum net photosynthetic rates (Pmax) were in the order of 1-3&gt;7080&gt;015-1&gt;004-1&gt;1-4, showing that clone 1-3 and clone 7080 had strong light environmental adapt-ability with the light saturation points (LSP) of 1 147.97 μmol/m2&#183;s and 1 196.31μmol/m2&#183;s, respectively, while clone 1-4 had the narrowest range of adaptation to light. There were differences in the total photosynthetic amount per area among the five clones that clone 1-4 was the best of 433 974.24 μmol/m2, fol owed by clone 1-3 of 401 290.20 μmol/m2. The transpiration rates (Tr) and stomatal conductances (Cond) of the five clones presented the same change trend. And the diurnal varia-tion curves of net photosynthetic rate (Pn) of clone 1-3, 1-4 and 015-1 showed two typical peaks with obvious midday depression, while clone 004-1 and 7080 didn’t. [Concluson] Considering a variety of photosynthetic characteristics of indica-tors, photosynthetic capacity of clone 1-3 was the best among the five Catalpa bungei clones.
文摘We studied the genetic polymorphism among 29 clones of shisham (Dalbergia sissoo Roxb) belonging to different geographic regions using random amplified polymorphic DNA (RAPD) markers. Out of 30 primers used, only 20 primers generated polymorphism in amplified product. In total 232 bands were amplified with 20 primers, of which 192 (82%) were polymorphic with an average of 9.6 bands/primer. The resolving power (Rp) ranged from 2.14 (Primer 5) to 11.93 (Primer 4). Primer 4 and Primer 3 possessed high Rp value. Polymorphism information content (PIC) ranged from 0.15 (Primer 5) to 0.37 (Primer 4). Primer 4 amplified total 18 bands in 29 genotypes with PIC value of 0.37 hence; this set of primer was most informative. The similarity coefficient analysis revealed two clusters. The first cluster comprised of only 10 clones and the second major cluster comprised of 19 clones. The genetic similarity among 29 clones ranged from 25.86% (clone 10 and 235) to 100% (clone 19 and 59), suggesting a wide genetic base in shisham clones.
基金supported by a Project of the State Forestry Administration and the PetroChina Company Limited Lin-you Integrated Bio-diesel Raw Forest Base
文摘It is very important to select and identify superior Xanthoceras sorbifolia Bge. trees for purposes of breeding and exploration. For our study, we selected superior X. sorbifolia trees using RAPD (random amplification of polymorphic DNA) technology. The results show that certain specific amplification bands emerged with significantly different frequencies between superior and non-superior trees. The 1400-bp band of No. 2121 primer emerged in the superior trees at a frequency 2.4 times that of the non-superior trees and the 600-bp band of No. 2153 primer in the non-superior trees at a frequency 2.5 times that of the superior trees There were very significant differences between the superior and non-superior trees. The frequency of the 1600-bp band of No. 1161 primer was the same in both kinds of trees, but significant differences were observed in point frequency (the frequency of the superior trees is 1,4 times that of the non-superior trees). These bands can be used as important targets to distinguish between superior and non-superior trees. The use of a combination of amplified bands simultaneously can play a guiding role in the selection of superior X. sorbifolia trees.
基金finically supported by the National Twelfth Five-Year Science and Technology Plan ‘‘Breeding of High yield and High Resistance New Species of Eucalyptus’’(2012BAD01B0401),‘‘Genetic Research of Pulp Yield and Veneer of Eucalyptus urophylla Hybrid Clones’’(RITFYWZX201304)
文摘Eucalyptus has become an important genus in China because it displays adaptability to a wide range of site conditions and produces pulp wood and veneer on short rotations. The aim of this study was to estimate genetic parameters and relationships and consider impli- cations for development of clonal forestry. We assessed growth traits, stem-branch characteristics, crown diameter and height of fresh branch for 20 Eucalyptus hybrid clones in China measured at the age of 44 months. Analysis of variance showed that there were significant differences in growth traits, height of fresh branch and stem straightness among clones. Significant differences in height, volume, crown diameter, height of fresh branch and branch size among replicates were also recorded. Coefficients of vari- ation ranged from 9.84 to 28.54 % for growth traits, 12.03 to 17.25 % for stem-branch characteristics, 18.26 % for crown diameter and 11.73 % for height of fresh branch. Estimates of repeatabilities for height, diameter at breastheight over bark, volume, crown diameter, height of fresh branch, stem straightness and branch size at clone mean level were 0.86, 0.80, 0.80, 0.54, 0.85, 0.77 and 0.44 respectively. Diameter at breast height over bark and height had strongly positive phenotypic and genotypic correlations with volume, ranging from 0.96 to 1.00. The positive genotypic and phenotypic correlations between growth traits and other studied traits suggested that fast growing clones always had bigger crown diameter, higher height of fresh branch, straighter stems and relatively smaller branches.
基金supported by Grants from the National Science and Technology Pillar Program of China(No.2015DAD09B01)
文摘Fifty-three larch interspecific hybrid clones(Larix kaempferi × L.gmelini) and their parent clones were used for growth curve analysis of height variations.The growth curves of the 55 clones were 'S'-shaped and 36 exhibited similar curves as the male parent.The coefficients of the logistic models were higher than 0.943,indicating that our results were effective in the simulation of the growth curves.ANOVA analysis showed significant differences in height of different clones (P/0.01).Average date of maximum height growth was Day 173,and average duration of rapid growth lasted for 50 days.Annual average increase in height was 9.7cm d^(-1) and daily average increase was 0.2 cm.The ratio of GR to the total annual increase in height ranged from 51.2 to 68.8%,with the average being 59.8%.There was a positive correlation between k values and plant heights which benefited from the evaluation of early plant height.There was also a positive correlation between GR(growth stage),GD(plant height) and annual increase in height.These results are informative to the evaluation of the elite clone selection and provide a theoretical basis for breeding and management.
文摘In order to understand the structural characteristics of lignin in triploid clones ofPopulus tomentosa and its changes in the processes of pulping and bleaching, milled wood lignin (MWL), lignin carbohydrate complex (LCC) and the residual lignin from kraft pulp (KP) and sulfite pulp (SP) were isolated and analyzed by Fourier transform infrared (FTIR) spectrum and ^13C nuclear magnetic resonance (NMR). The most diagnostic peaks were assigned and the differences were discussed. The spectral patterns reveal that triploid P tomentosa shows the specific features of hardwood from temperate areas, but in the spectrum of FTIR, the strength ratio orAl270 cm^-1 to A1226 cm^-1 is 0.88, higher than the average of hardwood from temperate areas, which will make the lignin delignification more difficult during pulping and bleaching. The LCC from triploid P tomentosa is mainly composed of xyloglucan and glucuronic acid, and other glucides have much lower ratio. In LCC FTIR, there are three peaks at 1 427, 1 329 and 1 046 cm^-1, indicating that both semi-cellulose and cellulose could exist in LCC, and that there might be relationships between cellulose and lignin. Compared with the residual lignin from KP and SP, the condensed structure in KP is more than that in SP.
基金Supported by National Natural Science Foundation (30070633 )National Science and Technology Supporting Project during the Eleventh Five-year Plan(2007BAD67B02)~~
文摘[Objective] The aim was to study the effects of drought stress on contents of endogenous hormones in leaves of different clones of Liriodendron chinense×L. tulipifera. Drought-resistant Liriodendron chinense×L. tulipifera clones NE25,NE78 and drought-sensitive Liriodendron chinense×L. tulipifera clones NE04,NE23 were selected as experimental materials to study the content changes of four kinds of endogenous hormones such as abscisic acid (ABA),indoleacetic acid (IAA),ribosylzeatin (ZR) and jasmonic acid (JA) in leaves of different clones under drought stress. [Result] Under drought stress,ABA was accumulated I leaves of different clones,however,the content changes in drought-resistant clones were not obvious; IAA content showed a decreasing trend,and the content changes n drought-resistant clones during later period of drought stress was decreased; JA content showed an increasing trend in leaves of drought-sensitive clones,indicating that drought-sensitive clones had to maintain higher contents of JA to resist drought stress. [Conclusion] The result of this study had provided scientific basis for the screening,planting and application of drougt-resistant clones of Liriodendron chinense×L. tulipifera.
基金supported by KPWN-Faculty of Forestry IPB research collaboration。
文摘Teak(Tectona grandis Linn. f.), one of the mostvalued tree species in the world, is slow-growing with a long period until it can be harvested;therefore, ensuring that only high-quality seedlings or clones are selected for planting is critical. The main objective was to determine performance and repeatability of selected clones in terms of growth and survival rates in different micro-environments. A 2-year clonal trial using 41 clones and a local seedling of teak as a control were grown at 4 microsites differing in spacing, soil fertility and alley crops to assess tree height, diameter and survival rate that was evaluated in Purwakarta, West Java, Indonesia using a randomized complete block design with four replicates of each clone at each microsite. Teak growth was influenced by clone(p < 0.01), microsite(p < 0.05) and clone 9 micrositeinteraction(p<0.01). The interaction clone 9 microsite resulted in several potential superior clones that differed in terms of growth rates at each microsite. On the basis of diameter only, superior clones(nos. 14, 18, 24, 30 and 37)were identified. Repeatability estimated was Rc2= 0.84 for diameter and Rc2= 0.77 for height. Growth performance of teak trees varied among microsites. Repeatability values for diameter and height characters were high. The effect of variable growth on each clone was influenced by genetic factors, environmental factors and the interaction of genetics 9 environment. Microsite significantly affected growth of teak clones. Clone 9 microsite interaction significantly affected growth of clones and led to the growth of superior clones at each microsite.
文摘Random Amplified Polymorphic DNA (RAPD) polymor- phism was employed to assess the genetic diversity in the elite germplasm'of Dalbergia sissoo. Sixty-seven clones that are under cultivation in northern India, originated frorri six different states of India and Nepal were analyzed with 30 RAPD primers that generated a total of 342 fragments out of which 290 were polymorphic. Total genetic diversity (Ht) varied between 0.01 and 0.37, with an average of 0.19. Shannon's Information index (I) varied between 0102 and 0.54, with an average of 0.31. Marker attributes like Polymorphism Information Content (PIC), Marker Index (MI) and Effective Multiplex Ratio (EMR) values were calculated to assess the discriminatory power of 30 primers used. The PIC values ranged from 0.01 to 0.37 with an average of 0.17 per primer and the EMR ranged from 0.17 to 21.00 with a mean of 8.66 across all genotypes. Closely related clones were C49 and C51 with similarity index of 0.86 while the least similar or most dissimilar clones were C14 and S-DB showing similarity index of 0.58. The UPGMA-phenogram categorized the 67 clones into six clusters based on genetic similarity and dissimilarity. The clustering of clones in relation to their geographical location has been discussed.
基金Supported by the International Science&Technology Cooperation Program of China(No.2013DFA31410)the Adaptive Response of Fishery Species to Environmental Changes and their Effects on Population Dynamics(No.2015CB453303)
文摘Ten microsatellite markers were used to analyze the levels of genetic diversity and inbreeding in a hatchery release population of Rhopilema esculentum Kishinouye (Scypbozoa: Rhizostomatidae). A total of 85 alleles were detected in 600 individuals. Within-population levels of observed (Ho) and expected (He) heterozygosity ranged from 0.152 to 0.839 (mean=0.464) and from 0.235 to 0.821 (mean=0.618), respectively. The polymorphism information content (PIC) of each marker ranged from 0.207 to 0.795 with an average of 0.580, indicating that the hatchery population maintained a high level of genetic diversity. Inbreeding levels were estimated in the hatchery population and the inbreeding coefficient was 0.203. This result revealed that a certain level of inbreeding occurred within the population. Meanwhile, we also determined genetic diversity at the clone level. Several polyps from the same scyphistomae were genotyped at the ten microsatellite loci and there was virtually no difference in their genotypes. Furthermore, we calculated the probabilities of exclusion. When both parents were known, the average exclusion probability often loci was 99.99%. Our data suggest that the ten microsatellite markers can not only be used to analyze the identity of individuals but they can also be applied to parentage identification. Our research provides a theoretical basis and technical support for genetic diversity detection and reasonable selection of R. esculentum hatchery populations. These findings support the use of releasing studies and conservation of R. esculentum germplasm resources.
文摘Poplar leaf defoliator, Clostera fulgurita (Walker) larvae were reared on three Populus deltoides clones (PL1, PL5 and PL7) in the laboratory. The nutritional indices were computed for working out the relationship between food consumption and growth rate of 3rd, 4th and 5th instar larvae on three clones. The result showed that the consumption index (CI), approximate digestibility (AD), growth rate (GR), relative growth rate (RGR) and efficiency of conversion of ingested food (ECI) decreased with the increase in the age of the larvae. Efficiency of conversion of digested food (ECD) increased with increase in age of the larvae. GR and RGR varied significantly, indicating that larval development was enhanced on PL1 as compared to PL5 & PL7. The values of AD, ECI and ECD were not affected by the different clones. Feeding and growth indices could be useful to define a defoliation prediction model.
文摘With four poplar clones, namely 84-323 (Populus deltoides cv. ?4-323?, 84-324 (Populus deltoides cv. ?4-324?, 79-35 (Populus ?euramericana cv. ?9-35?, and I-69 (Populus deltoides cv. 慙ux?I-69/55) as a control, researches on cold, drought and salt resistance of the clones were conducted. Electrolyte permeability under a series of low temperatures, relative water loss rate of detached leaves with time series and survival rate and growth performance in salt soil were measured. The results showed that 84-323, 84-324 and 79-35 were resistant to cold as same as I-69 (CK) and more resistant to drought and salinity than I-69 (CK).