共查询到20条相似文献，搜索用时 15 毫秒
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Our previous studies have revealed that the ThCAP gene plays a vital role in transgenic Populus (P. davidiana × P. bolleana) in response to cold stress. However, the regulatory mechanism of ThCAP gene expression has been unclear. In this study, the 5′ flanking region of the ThCAP promoter (PThCAP) was cloned using a genome-walking method. By analyzing cis-acting regulatory elements of PThCAP, a DRE motif and MYC and MYB elements were found to be located in the promoter. To identify the regulatory elements that control the expression of the ThCAP gene promoter, a series of deletion derivatives of PThCAP, P1–P5, from the translation start code (?1538, ?1190, ?900, ?718 and ?375 bp), were fused to the GUS reporter gene, and then each deletion was stably introduced into Arabidopsis thaliana plants. Deletion analysis of the promoter suggested that only the P2 fragment had strong GUS expression in leaves and roots of A. thaliana exposed to low temperature stress. These results suggest that this 290-bp region (?1190 to ?900 bp), as an important part in PThCAP, was associated with cold tolerance of A. thaliana. Our results provide evidence for the regulatory mechanism of ThCAP gene involved in the response to cold stress, and that the gene is promising candidate gene for genetic improvement of crops. 相似文献
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Information on population genetic structure and crop genetic diversity is important for genetically improving crop species and conserving threatened species. The PAL gene sequence is part of a multigene family that can be utilized to design DNA marker systems for genetic diversity and population structure investigation. In the current study, genetic diversity and population structure of 100 accessions of wild Pistacia species were investigated with 78 PAL markers. A protocol for using PAL sequences as DNA markers was developed. A total of 313 PAL loci were recognized, showing 100% polymorphism for PAL markers. The PAL markers produced relatively more observed and effective alleles in Pistacia falcata and Pistacia atlantica, with a higher Shannon’s information index and expected heterozygosity in P. atlantica, Pistacia vera and Pistacia mutica. Pairwise assessment of Nei’s genetic distance and genetic identity between populations revealed a close association between geographically isolated populations of Pistacia khinjuk and Pistacia chinensis. The accessions of wild Pistacia species had more genetic relationship among studied groups of species. Analysis of molecular variance indicated 19% among-population variation and 81% within-population variation for the PAL gene based DNA marker. Population structure analysis based on PAL revealed four groups with high genetic admixture among populations. The results establish PAL markers as a functional DNA marker system and provide important genetic information about accessions from wild populations of Pistacia species. 相似文献
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The lignin chemical structures of eight species of the Selaginella family, which are primitive vascular plants, were characterized by alkaline nitrobenzene oxidation, acidolysis, and ozonation. Selaginella involvens, Selaginella tamariscina, and Selaginella remotifolia were collected from the University Forest in Chiba, the University of Tokyo, Japan, and Selaginella biformis, Selaginella pennata, S. involvens, Selaginella chrysorrhizos, and unidentified Selaginella species (Selaginella sp.) were collected from northern Thailand. Lignin of all Selaginella species examined in this study was rich in syringyl nuclei. It was confirmed that a considerable portion of syringyl nuclei of Selaginella lignin formed syringylglycerol-β-aryl ether intermonomer linkages. The major diastereomer of arylglycerol-β-aryl ether intermonomer linkages of Selaginella lignins was the erythro-form exhibiting angiosperm lignin characteristics. In addition, lignins of S. involvens, S. tamariscina, and S. remotifolia collected from the University Forest in Chiba, the University of Tokyo, Japan, were isolated according to Björkman’s procedure, and structural features of the lignins were spectrometrically analyzed. It was confirmed that lignin of Selaginella species, which are primitive pteridophytes, was typical guaiacyl-syringyl type as well as being similar to angiosperm lignin. 相似文献
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Lecanicillium lecanii has been developed as biopesticides and widely used in the biological control of several insects in agricultural practice. However, the poor efficacy has blocked its application. The genetic manipulation has been proved as a useful tool to improve the virulence of entomopathogenic fungus. In this study, a scorpion toxin gene (BmKit) from Buthus martensi was cloned and transferred into L. lecanii and then its resulting activity against cotton aphids (Aphis gossypii) was assessed. The results showed that the engineered strain BmKit-12 grew significantly quicker than WT in host insects. The median lethal concentration (LC50) for BmKit-12 was 7.1-fold lower than that for WT, and the median survival time (LT50) for BmKit-12 was reduced by 26.5 % compared with that for WT. Although the conidial yield was reduced by 31.4 % on insect cadavers, the mycelia growth, sporulation, and conidia germination of BmKit-12 on plates were not significantly different from WT. Considering the lower amount of mycelia for BmKit-12 in host insects in late growth stage (fungal sporulation stage), we think the expression of BmKit may not affect the capability of sporulation. In conclusion, the expression of BmKit gene can significantly enhance the pathogenicity of L. lecanii against cotton aphids in a relatively cost-effective way. 相似文献
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Gabriele Rondoni Valeria Bertoldi Robert Malek Khaled Djelouah Chiaraluce Moretti Roberto Buonaurio Eric Conti 《Journal of pest science》2018,91(2):671-679
The invasive stink bug Halyomorpha halys is established in many European and American agro-ecosystems, where it causes severe crop losses. Potential control measures might include enhancement of plant defences. When attacked by herbivorous insects that oviposit on it, the plant may respond by priming direct defences, which might affect the development of future brood. Halyomorpha halys attacks numerous plant species in the invaded areas. Here, we investigated whether Vicia faba plants challenged by H. halys females can impair the development of its offspring through the activation of induced direct defences. We measured the weight and dimension of nymphs that developed on oviposition-experienced plants after 7 and 17 days from hatching. Nymphs that developed on oviposition-experienced plants weighed less compared to those that developed either on control plants or on plants solely subjected to H. halys feeding, and third instars showed shorter dimensions (tibia length). In addition, when oviposition-experienced plants were attacked by nymphs, higher and more rapid expression of two jasmonic acid-dependent genes (cysteine proteinase inhibitor gene and NAI1) was detected, possibly due to a mechanism of priming. Increased expression of the salicylic acid-responsive PR1 gene was also detected in egg-experienced plants, although the response was delayed compared to JA-dependent genes. Our results suggest that V. faba plants recognize H. halys oviposition as a warning signal and pre-activate defences against future nymphal herbivory. 相似文献
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Expansins are cell-wall-loosening proteins that have multiple roles during plant development and stress-related processes. In this study, a novel expansin gene PwEXP2 was cloned by rapid amplification of cDNA ends based on the cDNA library of Picea wilsonii and EST fragment of PwEXP2. It was found that PwEXP2 coded 253 amino acids, and putative signal peptides exist at the N-terminal, followed by 8 cysteines, a HFD (His-Phe-Asp) conserved domain, and 4 tryptophan residues at the C-terminal. PwEXP2 was located in cytoplasm and nucleus when transformed in an onion epidermal cell. Quantitative real-time PCR assays showed that PwEXP2 was expressed in various tissues with a relatively high level in needles and low level in mature pollen. The expression level of PwEXP2 dramatically increased after seed germination. Gene expression profiles in abiotic stresses showed that PwEXP2 was induced by high temperature and osmotic stress but not involved in ABA-dependent signaling pathway. These results display the important roles of the PwEXP2 in plant development and multiple adversity stresses. 相似文献
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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
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The naturally occurring Verticillium nonalfalfae shows promise for biocontrol of the highly invasive Tree of Heaven (Ailanthus altissima), but might also bear a risk for non-target tree species. In this study, we conducted inoculations on potted seedlings of A. altissima as well as on eight indigenous and two invasive tree species associated with Tree of Heaven in Austria. Although vascular discolourations developed in all inoculated tree species, V. nonalfalfae was reisolated from Ailanthus and eight of the ten non-target-species, whereas typical disease symptoms and mortality only occurred on A. altissima. Results confirmed high susceptibility (S) of A. altissima to V. nonalfalfae but indicated tolerance (T) of Acer campestre, Acer pseudoplatanus and Quercus robur, possible resistance (PR) of Fraxinus excelsior, Populus nigra, Tilia cordata, Ulmus laevis and Ulmus minor and resistance (R) of Fraxinus pennsylvanica and Robinia pseudoacacia to this potential biocontrol agent. Results from seedling inoculations were confirmed by cursory field observations in Ailanthus-inoculated forest stands, where admixed A. campestre, A. pseudoplatanus, F. excelsior, Populus alba, R. pseudoacacia and U. laevis canopy trees remained asymptomatic, while mortality was induced in Ailanthus. 相似文献
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Biochemical changes associated with flowering in Bambusa arundinacea Linn and Bambusa nutans Wall. ex Munro were analyzed. Gregarious flowering was initiated in natural areas and plantations of B. arundinacea in late 2014 and reached full bloom in early 2015, whereas sporadic flowering recorded during 2014–2015 in vegetatively propagated plants of B. nutans. Leaf and nodal shoot samples from flowering culms/shoots and nonflowering culms/shoots were collected in February 2015 at the initiation of fruit filling, then analyzed and compared for soluble sugars, phenols and peroxidase activity. In both species sugars were higher in leaves of flowering culms/shoots and lower in nodal shoots of flowering culms/shoots compared to the nonflowering. Phenols were lower in leaves and nodal shoots of flowering B. arundinacea, but higher in leaves and decreases in nodal shoots of B. nutans. Peroxidase activity increases in leaves and nodal shoots of B. arundinacea after flowering but increases in nodal shoots and decreases in leaves of B. nutans. 相似文献
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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
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T. Aznar-Fernández E. Carrillo-Perdomo F. Flores D. Rubiales 《Journal of pest science》2018,91(2):505-514
Pea weevil (Bruchus pisorum) is a damaging insect pest affecting pea production worldwide. The aim of this study was to identify sources of resistance to pea weevil in a Pisum spp. germplasm in multi-environment field tests. Seed infestation and larval development were assessed in each environment and subjected to a heritability-adjusted genotype and genotype x environment biplot analysis. Results showed that seed infestation and larval development are independent traits. Accessions P669 (P. sativum ssp. elatius) and P656 (P. fulvum) showed a stable reduction in seed infestation across environments. Meanwhile, accessions P314 (P. sativum ssp. elatius) and P1 (P. abyssinicum) showed a stable reduction in larval development. The most promising accession was P665 (P. sativum ssp. syriacum) which showed resistance at both pod and seed levels. This study demonstrates the importance of environmental conditions for pea weevil infestation. Moreover, by submitting data to a CCA, the influence of climatic parameters over seed infestation and larval development has been elucidated. 相似文献
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Bruno Vincent Fotini Koutroumpa Valérie Altemayer Géraldine Roux-Morabito Jeremy Gevar Carine Martin François Lieutier 《Annals of Forest Science》2008,65(1):111-111
As a consequence of the recent introduction of the pine wood nematode Bursaphelenchus xylophilus in Portugal, nematodes of the genus Bursaphelenchus were looked for in various French pine forests, in trees attacked by Monochamus galloprovincialis, the vector insect of B. xylophilus, and in the insects themselves. Trap trees were felled in 12 localities distributed all over the country. Nematodes were extracted from transversal stem discs; insects emerging from the trap trees were studied. B. hellenicus, B. leoni, B. mucronatus and B. sexdentati were isolated, but not B. xylophilus. The presence of B. mucronatus and the absence of B. xylophilus were confirmed by molecular markers. B. mucronatus was isolated from several regions with an average prevalence of 19%. The infestation of M. galloprovincialis by B. mucronatus reached 26.7%. The wide distribution of B. mucronatus in France could have an effect on the extension of B. xylophilus in a case of an introduction. 相似文献
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Marcus Hardie Daniel Mendham Ross Corkrey Eko Hardiyanto Alen Maydra Sabar Siregar Rianto Marolop Alun Wibowo 《New Forests》2018,49(1):87-104
Indonesia’s pulp and paper industry needs a large area of sustainably grown plantations to support its continued development. Acacia mangium has been the key species underpinning the pulp and paper industries in Sumatra, however increased disease pressure on A. mangium is expected to require large-scale conversion of Acacia plantations to Eucalyptus in the near future. The effect of such a large scale change in plantation species on soil moisture, for both tree production, and catchment hydrology is unknown. In this study we sought to characterize the impacts of plantation species (Acacia or Eucalyptus) and nitrogen management, on soil moisture, soil water depletion and depth to groundwater under stands of Acacia mangium and Eucalyptus pellita over the first 2–3 years after establishment. The study was conducted in experiments at four sites in Sumatra, Indonesia. Soil moisture and soil water depletion were not influenced by plantation species or fertilizer treatment. Soil moisture content and soil water depletion were strongly influenced by shallow groundwater at two of the four sites, however depth to groundwater did not influence stem growth. Results from the field trials cautiously suggest that large scale conversion of Acacia mangium to Eucalypt species in these regions is unlikely to result in increased moisture stress, nor is conversion of plantation species likely to lead to substantial differences in catchment hydrology. This study demonstrated the importance of conducting multi-site studies when investigating biophysical relationships in forest/plantation systems. 相似文献
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Sarwan Kumar 《Journal of pest science》2017,90(1):129-137
The large white butterfly, Pieris brassicae (L.), is an important pest of Indian mustard, Brassica juncea (L.) Czern., and inflicts heavy damage to all the above ground plant parts with strong yield reducing impacts. Farmers have few practical options other than to spray insecticides to protect their crop. In this study, an attempt was made during 2012–2013 and 2013–2014 crop seasons at Ludhiana, India, to evaluate Ethiopian mustard, Brassica carinata A. Braun as a trap crop to manage this pest as an alternate pest management strategy. B. carinata borders surrounding B. juncea were compared to chemically protected B. juncea and control (without B. carinata borders) plots for their effects on P. brassicae infestation and grain yield. Oviposition preference of adult butterflies was studied in a two-choice test in field cages, while the effect of two host plants on larval performance was studied under laboratory conditions under no choice conditions. B. juncea plots bordered with B. carinata harbored significantly lower larval population compared to control B. juncea plots during both the seasons. The grain yield in the bordered plots was also significantly higher than that from control plots and was statistically non-significant from that obtained in chemically protected plots. Female butterflies showed distinct oviposition preference for B. carinata over B. juncea and the larvae reared on B. carinata completed development in shorter period and grew bigger and heavier than those reared on B. juncea. Results indicated that B. carinata has potential to be used as trap crop to manage P. brassicae. 相似文献
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Taku Tsuyama Natsumi Shimada Taichi Motoda Yasuyuki Matsushita Yoshio Kijidani Kazuhiko Fukushima Ichiro Kamei 《Journal of Wood Science》2017,63(6):551-559
Bamboos are among the largest woody grasses and grow very rapidly. Although lignin is a crucial factor for the utilization of bamboo biomass, the lignification mechanism of bamboo shoots is poorly understood. We studied lignification in the bamboo Sinobambusa tootsik during culm development. Elongation growth began in May and ended in late-June, when the lignin content was approximately half that in mature culms. Thioacidolysis analysis indicated that p-hydroxyphenyl units in lignin formed even at late stages of lignification. The syringyl/guaiacyl ratio varied during culm development. Various lignin precursors were detected in developing culms by liquid chromatography–mass spectrometry. The ferulic acid content decreased from May to June, indicating that ferulic acid was utilized in early stages of cell wall formation. Monolignol glucosides were detected at early stages of lignification, whereas the contents of monolignols, coniferaldehyde, sinapaldehyde, p-coumaric acid, and ferulic acid peaked at later stages of lignification. Therefore, lignin precursors may be supplied differentially during the lignification process. In August, the rate of lignification decreased, although the contents of various lignin precursors peaked, implying that the rate-limiting step in the cessation of lignification in bamboo is transport or polymerization of lignin precursors, rather than their biosynthesis. 相似文献
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Barbara Moser Christoph Bachofen Jonathan D. Müller Marek Metslaid Thomas Wohlgemuth 《Annals of Forest Science》2016,73(4):959-970