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1.
对角倍蚜分批上树及接种方法对虫瘿数量和分布的影响进行了研究,结果表明:(1)迁飞接种(同批上树)时,单株虫瘿数为15.65个,而迁飞加挂袋(分批上树-A)及挂袋2次(分批上树-B)时,单株虫瘿数分别为48.39个和161.84个,增加了2.09倍和9.34倍;同时单叶虫瘿数也从1.69个增加到2.77个和3.42个;单株有虫瘿复叶数从8.70片增加到17.87片和46.00片;有虫瘿枝条率从21.65%增加到59.74%和91.58%。(2)迁飞接种时,虫瘿分布于当年生枝条第1~7片复叶,其中1~5片复叶为虫瘿主要分布叶片;迁飞加挂袋及挂袋2次时,虫瘿分布于当年生枝条的第1~8片及第1~11片复叶,其中第3~6片复叶为虫瘿主要分布叶片。(3)无论是干母同批上树还是分批上树,单叶虫瘿数均以1~3个为主,虽然分批上树时单叶平均虫瘿数从1.23个增加到1.47个和2.53个,但仍然低于单叶最适虫瘿数5~6个,对虫瘿的大小和生长没有不良影响。综上所述,干母分批上树可以显著增加角倍蚜虫瘿数量,提高虫瘿的分散度,充分发挥盐肤木形成虫瘿的潜力。 相似文献
2.
Seeds of Albizia chinensis(Osb.) Merr. in addition to water were also treated with different treatments by incubating in ethyl alcohol, acetone, and petroleum ether at room temperature for different du... 相似文献
3.
以盐肤木和黄栌为参照树种,用火炬树树叶水浸提液、林下土壤水浸提液浸种24 h,研究了浸提液对侧柏、油松、香椿、臭椿、小麦、小白菜种子萌发及幼苗生长的影响,研究了火炬树的化感作用。结果表明:火炬树完整鲜叶水浸提液处理小白菜种子,其发芽率和发芽势分别为88.0%、82.5%,与对照发芽率(94.0%)和发芽势(91.5%)无显著差异,而破碎鲜叶水浸液则极显著影响小白菜的发芽率和发芽势,分别降低为24.8%和5.0%;火炬树完整鲜叶和破碎鲜叶水浸液都能促进小白菜苗高生长,但都抑制小白菜胚根的伸长。与鲜叶相比,火炬树干叶水浸提液的化感作用明显降低。火炬树破碎鲜叶水浸提液极显著影响小麦发芽率,分别比对照的发芽率和发芽势降低11.0%和83.5%,干叶水浸提液则不影响小麦的发芽率,为95.0%,但发芽势比对照降低23.0%。与盐肤木和黄栌相比,火炬树破碎鲜叶水浸提液对小麦幼茎及胚根生长的抑制作用最强。火炬树破碎鲜叶水浸提液对4个乡土树种的种子萌发产生了不同程度的抑制作用,对香椿及臭椿发芽率的抑制作用极显著。火炬树破碎鲜叶水浸提液对4个树种的苗高以及油松苗胚根的伸长没有显著影响,但却极显著地抑制了侧柏、香椿及臭椿胚根的伸长。火炬树林下表层土壤水浸提液对小麦幼苗的生长没有抑制作用,能明极显著促进香椿的生长;处理55 d时,香椿苗平均高为8.63 cm,极其显著高于对照(5.14 cm)。 相似文献
4.
Soil microbes may be critical players in determining the allelopathic potential of some plants. Low levels of plant community biodiversity in Eucalyptus plantations have been attributed to the allelopathic potential of these tree species. The role of soil microbes in the allelopathic effect of leaf leachates of the hybrid tree Eucalyptus grandis × E. urophylla, was tested in Petri dish assays with Brassica chinensis as a receiver plant. Soils were collected from either a local garden (soil A) or a Eucalyptus plantation (soil B) and half of each soil was sterilized to remove microbes. These soils were then treated with E. grandis × E. urophylla leachates for 0–72 h. Seed germination of B. chinensis was significantly inhibited in soils treated with leaf leachates relative to untreated soils. The inhibitory effect of the leaf leachates was more pronounced in sterilized soils. Total phenolic content was obvious lower in nonsterile leachate-treated soils than in sterile soils. Biomass of B. chinensis was negatively correlated with the total phenolic content in soils. Our findings suggest that soil microbes can alleviate the allelopathic potential of Eucalyptus and thereby its negative impact on plant growth. 相似文献
5.
Yu Cao Junrui Zhi Runzhi Zhang Can Li Yan Liu Zhaoyun Lv Yulin Gao 《Journal of pest science》2018,91(1):79-91
Gardenia jasminoides and Rosa chinensis are economically important horticultural plants in China. Frankliniella occidentalis and Thrips hawaiiensis are serious coexisting pests that previously demonstrated opposite population trends on G. jasminoides and R. chinensis flowers. To further study the different performances between F. occidentalis and T. hawaiiensis, we investigated their population dynamics in the field (for 5 years) and their life history characteristics on the two flowers in the laboratory. In the field, the density of F. occidentalis was lower than that of T. hawaiiensis on G. jasminoides but was higher than that of T. hawaiiensis on R. chinensis. Under laboratory conditions, F. occidentalis showed significantly slower development, and lower survival and fecundity levels than T. hawaiiensis on G. jasminoides, but the opposite was true on R. chinensis. Significant differences in the net reproductive rate (R 0) between F. occidentalis and T. hawaiiensis were observed, with respective values of 38.66 ± 2.85 and 47.91 ± 2.70 on G. jasminoides, and 55.64 ± 2.15 and 32.45 ± 2.16 on R. chinensis. The intrinsic rates of increase (r m ) of F. occidentalis and T. hawaiiensis were 0.156 ± 0.008 and 0.198 ± 0.007, respectively, on G. jasminoides, and 0.172 ± 0.003 and 0.165 ± 0.002, respectively, on R. chinensis. Thus, the performances of both thrips with respect to population size in the laboratory were in accordance with those in the field, suggesting that the innate capacity for insect population increases may directly impact their population dynamics in fields. Thus, the population performance of different thrips species on flowers is species-dependent, which could be exploited in thrips control programs by breeding pest-resistant cultivars. 相似文献
6.
Dinh Duy Vu Thi Tuyet Xuan Bui Minh Tam Nguyen Dinh Giap Vu Minh Duc Nguyen Van Thang Bui Xiaohua Huang Yi Zhang 《林业研究》2017,28(2):265-272
Taxus chinensis and T. wallichiana in have been threatened in their distribution areas in recent decades because of their over-exploitation and reduction and destruction of native habitats. Determining the genetic diversity in populations of the two species will provide guidelines for their protection and preservation. Two hundred and fifteen trees from six populations of T. chinensis and 150 sampled trees of T. wallichiana were sampled. Six microsatellite primer pairs selected from 16 primer pairs were used to investigate genetic variation at the population and species levels. Five yielded polymorphic alleles, and among the 13 putative alleles amplified, 11 were polymorphic (accounting for 76.33 %).Shannon’s information index (I) and percentage of polymorphic bands (PPB) (I = 0.202 and PPB = 67.22 % for T. chinensis; I = 0.217 and PPB = 65.03 % for T. wallichiana). Both species had low levels of genetic diversity (mean H o = 0.107, H e = 0.121 for T. chinensis; H o = 0.095, H e = 0.109 for T. wallichiana). Genetic differentiation among populations was higher (F ST = 0.189) for T. chinensis and lower (0.156) for T. wallichiana, indicating limited gene flow (Nm) among populations for T. chinensis (0.68) and T. wallichiana (0.65). Variation among individuals of T. chinensis was 63.59 and 73.12 % for T. wallichiana. Thus, the threatened status of the two conifers is related to a lack of genetic diversity. All populations are isolated in small forest remnants. An ex situ conservation site should be established with a new population for these species that comprises all the genetic groups for the best chance to improve their fitness under environmental stresses. 相似文献
7.
Seed mass and emergence time may influence fitness of plants. The experiments were conducted to investigate the effects of seed mass and emergence time on the performance of seedlings of Castanopsis chinensis, a large evergreen tree species with limited tolerance of shade. The treatment consisted of three light regimes: 100%, 15% and 2% of full sunlight. Germination rate and germination time showed a significant correlation with seed mass. Germination rate differed among the three light regimes. Early-emerging large-seeded seedlings in 100% light produced the heaviest seedlings, while those resulting from smaller late-emerging seeds and grown under 2% light regime produced the lightest seedlings. Relative growth rate (RGR) decreased with seed mass in all three light regimes, and seedlings of C. chinensis have a higher RGR in high and intermediate light levels compared to low light. In contrast, the effect of emergence time on RGR was not significant. The growth of C. chinensis seedlings were significantly influenced by seed size, emergence time, and light conditions. For each month, the mean height of seedlings was significantly greatest for large-seeded seedlings and significantly lowest for small-seeded ones, irrespective of emergence time and light conditions. Regeneration success of C. chinensis appears to be regulated by the interactive effect of seed mass, emergence time and light regime. 相似文献
8.
Fang-Fang Yang Yue-Lin Li Guo-Yi Zhou K.O. Wenigmann De-Qiang Zhang Mike Wenigmann Shi-Zhong Liu Qian-Mei Zhang 《Forest Ecology and Management》2010
The biomass and decomposition of coarse woody debris (CWD, ≥10 cm in diameter) were studied in a monsoon evergreen broad-leaved old-growth forest in Dinghushan Nature Reserve, Southern China. The study examined the biomass of CWD from 1992 to 2008 and decomposition of three dominant tree species CWD (Castanopsis chinensis, Cryptocarya concinna, Schima superba) from 1999 to 2008. Changes in the wood density of three tree species’ CWD were used to estimate the decay rates with a single exponential model. The results showed that the biomass of CWD in the old-growth forest was increasing from 17.41 tonnes ha−1 (t ha−1) in 1992 to 38.54 t ha−1 in 2008, and a higher decay constant was observed for C. concinna (0.1570 – 19 years for 95% mass loss); the decay rates of S. superba and C. chinensis were 0.1486 (20 years for 95% mass loss) and 0.1095 (27 years for 95% mass loss), respectively. The difference in decay constant rates may be due to their substrate quality and decomposers. The content of carbon (C) in three species declined after 9 years of decay. Nitrogen (N) content increased in all species with decay. The C/N ratio in the three species declined during the decay process. 相似文献
9.
3,12-Dihydroxy-cis-3,4-methylenedodecanoic acid 3-O-β-d-glucopyranoside, trivially named litchioside C (1), the first cyclopropyl-containing fatty acid glycoside, was isolated along with three previously uncharacterized galactosylacylglycerols from the seeds of Litchi chinensis. Its structure was established on the basis of spectroscopic analysis including HRESIMS and 2D NMR spectra. Its antioxidant and antibacterial activities were evaluated and its biogenetic pathway was discussed. 相似文献
10.
Zheng-Hong Pan Yan Li Jin-Lei Liu De-Sheng Ning Dian-Peng Li Xing-De Wu Yong-Xin Wen 《Fitoterapia》2012
A new cardenolide tupichinolide (1) and a new steroidal saponin tupichinin A (2), together with seven known compounds, were isolated from the rhizomes of Tupistra chinensis. Their structures were established using spectroscopic analysis and chemical methods. Compound 1 was the first cardenolide isolated from Tupistra chinensis and exhibited potent cytotoxicity against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480. 相似文献
11.
Nndamuleleni Romeo Murovhi Simeon Albert Materechera Sendros D. Mulugeta 《Agroforestry Systems》2012,86(1):61-71
Litter fall from upper storey trees in agroforestry systems contributes to nutrient cycling for the benefit of all components of the system besides serving as mulch. This study examined the seasonal changes in the quantity and quality of leaf litter fall from three sub-tropical fruit trees viz: avocado (Persea americana L.), mango (Mangifera indica L.) and litchi (Litchi chinensis L.) which have potential for use in agroforestry. Leaf litter production was estimated using nylon mesh litter traps erected over five randomly selected trees of each species in a completely randomised design. Litter quality was determined by analysing ash content and polyphenol, carbon, cellulose, lignin and nutrient concentrations over a 2?year period (2007?C2008). Total annual leaf litter production during the study period (dry matter basis) was 8.3, 6.3 and 5.6?t?ha?1?year?1 for litchi, mango and avocado, respectively. In both years, leaf litter fall was greatest during autumn and lowest during winter in all species. There were no significant differences in S, Ca, Mg and Mn concentrations in the leaf litter, but polyphenol, N, P and K concentrations differed significantly (P?<?0.05) between species. It was concluded that litter quality from all three tree species was low and would require appropriate management to improve its quality. 相似文献
12.
The yellow-legged hornet (Vespa velutina) is the first invasive Vespidae predator of honeybees to be accidentally introduced into Europe from Asia. In the current pollinator decline, V. velutina is an additional stressor for honeybees and other pollinators. Although V. velutina contributes to the loss of honeybee colonies, little is known about its biology and behaviour both in the native and in the invaded area. Here, we review the current knowledge of this species and describe its life cycle and life history traits (reproduction, overwintering, foraging and dispersal) in the light of the biology of other Vespidae. We also review the impact of this species on ecosystems, on the economics of beekeeping, and on human health (this species being potentially deadly for allergic people). Based on this information and on previous worldwide experiences with Vespidae invasions, we propose key research topics for the development of effective management plans. We identify methods to limit the impact and proliferation of V. velutina in Europe that are based on nest destruction, trapping, population genetics, and biological control. In our opinion, research effort on the means to detect and destroy V. velutina nests at an early stage is required in order to short-circuit the colony cycle and thus limit both its impact on honeybees and its expansion through Europe. Finally, we discuss the impact of this biological invasion on the development of methods that should be used to manage alien species in the future. 相似文献
13.
14.
Rongbo Wang Shuzhun Chen Bowen Zheng Peiqing Liu Benjin Li Qiyong Weng Qinghe Chen 《Forest Pathology》2019,49(5)
Taxus chinensis is a valuable tree with uses for timber, medicinal, ornamental and landscape purposes. Most importantly, it is a source of the anti‐cancer drug paclitaxel. In 2016, needle spot disease was observed on T. chinensis in Fujian Province of China. Five isolates of similar morphology were isolated from diseased samples. The pathogen was identified as Neopestalotiopsis clavispora based on morphological and cultural characteristics and confirmed by sequence analysis of the internal transcribed spacer region (ITS) and the large subunit ribosomal RNA gene (LSU). The pathogenicity of the isolates was confirmed by fulfilling Koch's postulates. To the best of our knowledge, this is the first report to indicate that the causal agent of needle spot disease on Chinese yew in China is N. clavispora. 相似文献
15.
Chao DC Lin LJ Kao ST Huang HC Chang CS Liang JA Wu SL Hsiang CY Ho TY 《Fitoterapia》2011,82(4):696-703
Zuo-Jin-Wan (ZJW) has been used to treat hepatocellular carcinoma in Asia. This study was to determine whether ZJW and its components blocked activator protein 1 (AP-1) and nuclear factor-κB (NF-κB) activities as well as tumor promotion in hepatoblastoma HepG2 cells. ZJW and its components, Coptis chinensis and Evodia rutaecarpa, inhibited AP-1 and NF-κB activities, and suppressed anchorage-independent growth of HepG2 cells. The major alkaloidal ingredients, berberine and evodiamine, inhibited AP-1 activities and/or NF-κB activation, and further suppressed hepatocellular transformation. In conclusion, ZJW and its constituents, berberine and evodiamine, suppressed tumor promotion primarily through AP-1 and/or NF-κB pathways in HepG2 cells. 相似文献
16.
The genus Spodoptera contains some of the most destructive crop pests in the world owing to the worldwide distribution of the different species and their wide host ranges. Uses of semiochemicals for insect control have been recently reviewed, but strategies developed specifically against Spodoptera species are scarce. In this review, we present an updated account of the semiochemicals and other natural product-based approaches to monitor and control the most damaging Spodoptera spp. In general, successful control of Spodoptera littoralis, S. frugiperda, S. litura, and S. exigua have been reported through mass trapping, mating disruption, and attract-and-kill methods. An updated survey of the pheromone components of these species and an outlook of future perspectives against these pests are also outlined. 相似文献
17.
以五倍子蚜的主要生产种-角倍蚜为研究对象,对其生活周期中7个蚜型的形态特征进行显微测量分析。结果表明:各蚜型的形态特征与其分工相适应,春迁蚜和秋迁蚜体型大,具有发达的足、翅、触角和次生感觉圈,与其迁移和繁殖的分工相适应。干雌和越冬若蚜体型稍小,具有较发达的足和口器,与其取食、繁殖或越冬的分工相适应。干母体型最小,但体型修长,具有发达的足和喙,与其取食、形成虫瘿和繁殖的分工相适应。雌、雄性蚜体型小,口器完全退化,足不发达,与其交配和繁殖的分工相适应。结合各蚜型生活环境的变化,探讨角倍蚜对环境的适应性。 相似文献
18.
Morphological and biochemical changes of Chinese horse chestnut (Aesculus chinensis Bge.) seeds were studied during the process of maturation. Fruit and seed diameter increased linearly from DPA (Days Post Anthesis) 60 to DPA 150 and were stable thereafter. The weight of fruit and seed increased sigmoidally between DPA 100 and DPA 160. The water contents of whole seeds, axes and cotyledons had a sharp reduction from DPA 110 to DPA 130 but changed little after DPA 130. The water contents of whole seeds, axes and cotyledons were 1.42, 1.93 and 1.30?g?g?1DW, respectively at the end of maturation. The starch content of cotyledons from mature seeds was high on a dry weight basis (31.4%) while the total soluble sugar content varied between 12 and 20%. In both axes and cotyledons, the total soluble sugar content decreased during the process of maturation, as did all five soluble sugar components measured (glucose, sucrose, trehalose, raffinose and stachyose). Sucrose and stachyose contents remained relatively high at the time of seed maturation, followed by glucose and a trace level of trehalose. The oligosaccharide/disaccharide (O/D) ratio in the axes was 3.1 at DPA 140. The high level of sucrose and stachyose might contribute to the greater desiccation tolerance of Aesculus chinensis seeds relative to typical recalcitrant tropical seeds. High levels of ABA content in seed coats and a low GA3/ABA ratio in both seed coats and axes might also influence the desiccation tolerance and shallow dormancy of mature Aesculus chinensis seeds. 相似文献
19.
Lene R. Nielsen Lea V. McKinney Ari M. Hietala Erik D. Kjær 《European Journal of Forest Research》2017,136(1):59-73
In Europe, common ash (Fraxinus excelsior) is being decimated because of the invasive fungus Hymenoscyphus fraxineus. In its native range in Asia this ascomycete is considered a harmless leaf associate of F. mandshurica and F. chinensis subsp. rhynchophylla. Field observations from Europe suggest that there is species-specific variation in disease susceptibility among European and North American Fraxinus species, but a wider comparison at the genus level has been missing so far. We assessed disease symptoms and pathogen apothecium development in 17 Fraxinus species from Asia, Europe and North America exposed to high infection pressure in a Danish arboretum. We also tested their susceptibility to pathogen infection through controlled stem and leaf inoculations and subsequently assessed the level of pathogen DNA by a qPCR assay. The results suggested the presence of a phylogenetic signal in disease susceptibility where closely related Asian, European and North American species in section Fraxinus had relatively high levels of H. fraxineus DNA in the leaves and supported high production of apothecia. Leaves from some North American species also contained relatively high levels of H. fraxineus DNA, supported moderate production of apothecia and developed lesions—stating the need to avoid introduction of H. fraxineus to North America. 相似文献
20.
Seed limitation of desired indigenous species has constrained the succession of established plantations from an early successional
stage, to more natural forests in South China. Because of its low cost and time-saving advantages, direct seeding has been
considered a useful method in forest regeneration. To improve our understanding of whether and how direct seeding can lead
to the establishment of indigenous tree species, we carried out an experiment in four typical plantations (eucalyptus, mixed-native,
mixed-legume, mixed-conifer) and a shrubland in South China. We also tested the effect of understory vegetation and litter
removal on seedling establishment and growth. Seeds of three indigenous tree species (Castanopsis chinensis, Cryptocarya chinensis, and Psychotria rubra) were sown with understory vegetation and litter either retained or removed. Seedling emergence, survival, and growth were
recorded for 21 months. We found that conditions that favored seedling emergence often differed from those that favored seedling
survival. While the removal of understory vegetation and litter did not influence the final seedling establishments for all
the three introduced species, growth of Psychotria rubra was influenced at several sites. Seed mass was positively correlated with seedling emergence and subsequent growth. The large-seeded
Castanopsis chinensis showed higher emergence and growth than the intermediate-seeded Cryptocarya chinensis or the small-seeded Psychotria rubra. Seedlings of Castanopsis chinensis grew better in plant communities with high understory light penetration and high soil exchangeable potassium. Growth of P. rubra seedlings decreased significantly with soil hydrolyzed nitrogen. In conclusion, direct seeding can be useful for the establishment
of indigenous tree species into plantations and shrubland. Optimizing early seedling establishment and growth will require
the selection of suitable native species for improving seedling establishment in different plantations. Additionally, understory
vegetation and litter and fertilizer should be properly managed to enhance the establishment of certain indigenous tree species. 相似文献