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1.
Collembola of buttongrass moorlands in Tasmania were surveyed monthly over a 12 month period, using sweep nets and pitfall traps, at two locations, one at 760 m and the other at 325 m altitude. At each location, there were two pairs of sites with each pair straddling a fire boundary. The younger regrowth sites had been burnt less than 12 years previously and the older regrowth sites burnt more than 24 years previously. Nearly 30,000 individuals were collected belonging to 42 taxa. Most Collembola were identified to morphospecies with virtually all mature specimens identified to genus level and immature specimens recognised to family level. Three named species were recorded. Genera with Gondwanan (41%) and cosmopolitan (33%) distributions dominated the Collembola of buttongrass moorlands. The Collembola communities differed significantly between locations and this, in part, reflected differences in vegetation. Brachystomellidae, Odontellidae, Paronellidae, Katiannidae n. gen. and Sminthurididae were more common at the high altitude sites where the vegetation contained more grasses and sedges and occurred on relatively fertile soils. Parakatianna spp., cf. Tomocerura spp., cf. Drepanura sp., Sminthurinus spp. and Rastriopes sp. were more common at the low altitude sites where the vegetation contained more shrubs and occurred on relatively infertile soils. The Collembola community differed significantly between seasons with one group of taxa being more common in autumn and/or winter (Acanthomurus spp., cf. Tomocerura spp., Paronellidae, Lasofinius spp., Polykatianna cf. aurea, Parakatianna spp., Sminthurinus spp. and Katianna spp.) and another group of taxa more common in summer or summer and autumn (Odontellidae, cf. Drepanura sp., Rastriopes sp., Corynephoria sp. and Dicyrtomidae). We found some evidence of a difference between Collembola communities in the two ages of regrowth we compared but only for the low altitude sites. Polykatianna cf. aurea, Parakatianna spp., Sminthurinus spp., cf. Tomocerura spp. and Rastriopes sp. were caught in lower numbers on young regrowth sites compared with old regrowth sites. We also present data from another low altitude site where we used a space-for-time design to further investigate the impact of fire on Collembola. We found a significant positive relationship between age of buttongrass regrowth and the number of Rastriopes sp. caught and this was correlated with the ground cover of plant species within the family Myrtaceae.  相似文献   

2.
Bacteria of the genus Wolbachia (Rickettsiae) are endosymbionts found in many species of invertebrates. The traditional division of Wolbachia lines into four supergroups has recently been challenged with the finding of a fifth supergroup. Until now, this E supergroup exists of a single host species of the order Collembola (springtails) and is hypothesized to form a ‘missing link’ between Wolbachia lines in higher arthropods and nematodes. We have sequenced the 16S rDNA, the ftsZ and the wsp genes of a Wolbachia lineage present in the sexually reproducing collembolan Orchesella cincta. We tested the hypothesis on the origin of Wolbachia in Collembola by adding this new Wolbachia lineage and a lineage found in the collembolan Mesophorura macrochaeta to the Wolbachia phylogenetic tree. The addition of these two species clearly shows that Wolbachia is not monophyletic in Collembola. We conclude that the origin of Wolbachia in Collembola is a combination of vertical and horizontal transfer between coexisting species.  相似文献   

3.
两种森林集水区径流量及其径流过程初步分析   总被引：1，自引：0，他引：1  
研究桉树林和马尾松林集水区的径流量及其径流过程,为科学评估森林的水源涵养功能提供参考依据。于2013年8月—2014年7月运用小流域径流监测方法和自动采集数据,对桉树林和马尾松林集水区的径流量进行定位观测,并分析强降雨和连续降雨对径流过程的影响。结果表明:桉树林集水区的年径流深和径流系数分别为107.7 mm和8.2%,马尾松林的依次为319.4 mm和24.2%。在前期没有径流情况下,一次强降雨过程（降水量147.5 mm）,两种森林集水区的径流历时、径流最大值滞后于降雨峰值的时间和总径流深都存在明显差异,桉树林的分别为13.8 h,0.2 h和35.6 mm,马尾松林的依次为35.5 h,0.7 h和28.5 mm。一次连续7 d的降雨过程（降水量125.0 mm）,桉树林集水区只产生4 d径流,总径流深仅3.8 mm;马尾松林集水区则连续产生13 d径流,总径流深达10.1 mm。综上所述,马尾松林的水源涵养功能明显优于桉树林。  相似文献   

4.
Bacteria in the genera Photorhabdus and Xenorhabdus are highly pathogenic to insects and are symbiotically associated with nematodes in the genera Heterorhabditis and Steinernema, respectively. We compared extracellular protease production and resistance to antibiotics (chloramphenicol, erythromycin, neomycin and tetracycline) for 32 isolates of P. luminescens and 11 isolates of X. poinarii taken from nematodes isolated from soil in southern New Jersey. P. luminescens produced greater amounts of protease, and was more resistant to erythromycin and less resistant to neomycin than X. poinarii. No interspecific differences in resistance to chloramphenicol or tetracycline were detected. Variability within species was not related to the site, habitat or soil core from which the isolates were obtained, and was not associated with variation in the color of the host cadaver for P. luminescens. Resistance to erythromycin was positively correlated with resistance to both neomycin and tetracycline for P. luminescens, but was negatively correlated with resistance to neomycin for X. poinarii. Antibiotic resistance profiles and extracellular protease production might be useful characteristics for distinguishing among species and strains of these bacteria, probably have ecological significance with respect to intra- and interspecific competition within host cadavers, and could have implications for the utility of these organisms for biological control.  相似文献   

5.
This study examined an ‘invasional meltdown’, where the invasion of a Midwestern woodland by an exotic shrub (Rhamnus cathartica L.P. Mill) and the invasion by Eurasian earthworms facilitated one another. Using a litterbag approach, we examined mass loss of four substrates (R. cathartica, Acer saccharum, Quercus rubra, and Quercus alba) along a gradient of Eurasian earthworm density and biomass throughout a 40.5 ha oak woodland in Glencoe, Illinois. Earthworm densities and biomass were greatest in patches where R. cathartica prevailed, and populations were lowest in an upland forest subcommunity within the woodland. At each of three points along this earthworm gradient, we placed replicated litterbags constructed either to permit or to deny access to the litter by earthworms. The treatments were, therefore, plot treatments (low, medium and high earthworm density and biomass) and litterbag treatments (earthworm access and earthworm excluded). We found that earthworms promoted a very rapid loss of litter from R. cathartica bags. Within 3 months greater than 90% of this litter was lost from the litterbags. Earthworm impacts on other substrates followed the sequence A. saccharum>Q. alba=Q. rubra. Effects of both litterbag and plot treatments were found within 3 months for A. saccharum but Quercus species were affected only after a year. We propose that the impact of earthworms on litter breakdown creates conditions that promote and sustain invasion by R. cathartica. Previous work has demonstrated that R. cathartica may alter soil properties in a way that promotes and sustains invasion by earthworms. These findings have implications for the restoration management of these systems, since the legacy of R. cathartica on soil properties and earthworm populations may persist even after the plant has been physically removed.  相似文献   

6.
Investigations to determine stable or source-sink animal population dynamics are challenging and often infeasible for most species due to the time and expense of mark-recapture studies and the challenge of life histories attributes that result in low detectability and low recapture probabilities. Often, managers rely solely on occupancy or relative abundance patterns to assess a species’ sensitivity to environmental changes. Greater insight into population-level responses to environmental change can be gained by consideration of a combination of readily obtainable metrics, including occupancy, relative abundance, demographic structure and body condition. We examined how these metrics can improve our understanding of population-level responses to forest disturbance, using datasets for two exemplar species of terrestrial salamanders resident to the Pacific Northwestern USA. We compared population metrics for the Del Norte salamander (Plethodon elongatus) and the Siskiyou Mountains salamander (Plethodon stormi) across the seral continuum represented by four forest age classes: pre-canopy, young, mature, and old-growth. We compared these data with those collected from reference stands in mature (P. stormi) or old-growth (P. elongatus) forest containing robust populations. P. elongatus was twice as common as P. stormi. Both occupancy and salamander counts were lowest at pre-canopy sites for both species. Although there were numerous P. elongatus detections in young forests, higher proportions of these individuals were juveniles and sub-adults when compared to populations in late-seral forests. We found a negative relationship between the proportion of immature animals and total counts at a site, indicating that the high proportion of young animals in young forest stands is likely due to dispersal of young salamanders from nearby source populations and/or low survival of adult animals in young forests. We also found reduced body condition of P. stormi populations in young forests. Our results suggest that there are costs to populations occupying early seral forests, such as skewed age class structure and reduced body condition that are indicative of sink populations. Consideration of population-level metrics beyond occupancy and relative abundance can provide important insights when assessing a species’ sustainability in managed forest landscapes.  相似文献   

7.
River corridor plants in Central Europe have in recent decades become increasingly rare, caused mainly by habitat destruction and change. The aim of this study was to examine the impact of soil quality, but especially of habitat fragmentation in terms of population size and isolation, on seed production and germination of five selected species, all of which being endangered, perennial herbs: Euphorbia palustris, Lathyrus palustris, Pseudolysimachion longifolium, Sanguisorba officinalis, and Senecio paludosus. We sampled totally 58 populations in flood plains in the surroundings of Bremen, North-western Germany.

In all five species, there were positive correlations between the number of seeds (total seed mass) and plant height, as well as between germination and seed mass. Seed traits values and/or germination were negatively affected by small population size, in Euphorbia, Lathyrus and Pseudolysimachion additionally by high population isolation. There were also significant effects of soil quality, but these were less consistent across species. The contribution of population size and isolation, compared to soil quality, to the variance explained in the reproductive components was especially high in Euphorbia and Lathyrus, the only two species depending on insect pollination.

The results indicate that the five species are likely to decline as a consequence of decreased plant fitness in small and/or isolated populations, probably caused by pollen limitation. The studied species may be representative for the group of river corridor plants as a whole that are often restricted to isolated remnants of near-natural flood plain vegetation in a matrix of heavily used agricultural land.  相似文献   


8.
Soil microorganisms may play an important role in the uptake of heavy metals from soils. However, assessments of bacterial activity and community composition in the rhizosphere of accumulators have been largely ignored. We studied potential effects of a copper (Cu)-accumulator, Elsholtzia splendens, and a non-Cu-accumulator plant, Trifolium repens, on soil microbial activity and community composition with increasing Cu addition. The results showed that concentrations of Cu in the shoots of E. splendens were 2.1, 2.2 and 2.4 times those of T. repens under the treatment of different Cu concentrations. Soil microbial biomass and phosphatase activity in the rhizosphere of E. splendens were higher than those of T.repens. PCR-denaturing gradient gel electrophoresis (PCR-DGGE) fingerprint analysis revealed that addition of Cu decreased the number of bands in bare soil and soil with T. repens. However, there was a significant increase in the number of bands in soil with E. splendens incorporated with either 200 or 500 mg kg−1 Cu. The abundances of five phylogenetic groups related most closely to -, β-, γ-proteobacteria, Gram-positive bacteria and CFB group, respectively, were determined in the rhizosphere of plants. Some specific clone such as E13 (metal-contaminated soil clone K20-64) was found in the rhizosphere of E. splendens. Results indicated that E. splendens, as a Cu-accumulator, played an important role in governing soil microbial activity and bacterial community composition in the rhizosphere in response to Cu stress.  相似文献   

9.
Food preferences of earthworms for soil fungi   总被引：9，自引：0，他引：9  
Soil fungi are considered to be an important food source for earthworms. Selection experiments were carried out in order to study the preferences of earthworm species for a variety of soil fungi. Nine fungal species (Cladosporium cladosporioides, Rhizoctonia solani, Mucor sp., Trichoderma viride, Fusarium nivale, Phlebia radiata, Glaeophyllum trabeum, Coniophora puteana, Coriolus versicolor) were grown separately in centrifuge tubes on sterilized sand with potato dextrose. Tubes containing different fungal species, 8–9 per experiment, were arranged in a food choice arena. The preference for the fungi of 5 different earthworm species (Lumbricus terrestris, Lumbricus castaneus, Aporrectodea caliginosa, Aporrectodea rosea, Octolasion cyaneum) was tested by adding one specimen per chamber. Removal of sand from the tubes within 6 days was used as the indicator of preference by earthworms. The food preference of earthworms irrespective of ecological group followed a general pattern. F. nivale and C. cladosporioides were the preferred fungal species, followed by fast-growing species such as Mucor sp. and R. solani. In contrast, basidiomycetes were generally refused. The epigeic species L. rubellus had the strongest preference for a single fungal species, in contrast the endogeic species A. rosea fed more evenly on different fungal species. We conclude that early successional fungal species are used as cues by earthworms to detect fresh organic resources in soil.  相似文献   

10.
刘戈辉  韩泽刚  孙士超  张薇 《核农学报》2021,35(12):2733-2745
乙烯响应因子(ethylene responsive factor, ERF)可以激活或者抑制下游病程相关蛋白基因的表达,在植物抗病信号转导途径中发挥着重要作用。为探究ERF-B3亚组基因GhB301在棉花抗枯萎病中的分子调控机制,本研究利用已获得的转GhB301基因棉花株系,通过孢子悬浮液蘸根的方法对转GhB301基因棉花株系(N)和野生型对照(WT)进行接菌处理,抗病性鉴定结果表明,过表达GhB301的N株系增强了对枯萎病的抗病性,其病情指数为14.77,显著低于WT(病情指数为37.50);枯萎病菌侵染0、6、12、24、48 h后,利用RNA-seq技术对N和WT的根部组织进行测序分析,共得到273 111 170个clean reads,其Q30均大于87.64%,将clean reads与陆地棉参考基因组TM-1比对,获得了14 021个差异表达基因(DEGs)。与WT相比,转基因株系能够在病原菌侵染后更快速地做出响应。GO及KEGG富集分析发现共有135个DEGs参与氧化还原过程,67个DEGs参与防御反应,31个DEGs参与苯丙烷类生物合成,推测这些DEGs可能与转基因棉花的枯萎病抗性增强存在密切关系。本研究结果为阐明GhB301基因响应棉花枯萎病菌侵染规律奠定了基础。  相似文献   

11.
以不同恢复年限下煤矿复垦区3种共有植物油松、沙棘、苜蓿的叶片作为研究对象,通过对其碳、氮、磷含量及生态化学计量学特征的研究,探讨退化生态系统植物内稳性、植物养分状况及不同植物与氮磷限制率的关系,以期为该复垦区植物的选择及复垦效果评价提供科学合理的建议与参考。结果表明:矿区植物叶片碳、氮、磷含量平均值分别为488.33,24.87,1.39 g/kg,三种植物叶片碳含量随着恢复年限的增加均有所增加,其中油松叶片碳含量显著高于沙棘和苜蓿叶片碳含量（p < 0.05）,沙棘和苜蓿叶片氮含量显著高于油松叶片氮含量（p < 0.05）;矿区植物叶片C∶N,C∶P和N∶P平均值分别为26.76,374.72,18.32,在生活型方面三种植物叶片N∶P大小表现为灌木>草本>乔木,油松生长受到氮元素的限制,沙棘和苜蓿生长受到磷元素的限制;植物叶片氮含量与磷含量、C∶N,C∶P和N∶P呈极显著相关（p < 0.01）。该研究结果有助于进一步了解准格尔旗矿区碳、氮、磷元素在不同植物间的相互作用规律与机制,对指导矿区植被恢复中树种选择有一定意义。  相似文献   

12.
Failure to consider both the consumptive and non-consumptive effects of predators on prey can lead to erroneous conclusions about the net effect of the relationship. The predatory devil crayfish, Cambarus diogenes Girard functions as an ecosystem engineer constructing extensive burrow systems through aquatic habitats. Despite crayfish posing a serious predation threat, preliminary data indicate that the federally endangered Hines Emerald dragonfly larvae, Somatochlora hineana Williamson regularly inhabit crayfish burrows. During late summer, S. hineana larval habitat dries up; leaving crayfish burrows as some of the only wetted habitats. Thus, C. diogenes can affect S. hineana through both direct, negative and indirect positive effects. We examined the positive role of crayfish burrows as drought refuges, and the threat of predation by C. diogenes on S. hineana larvae. Monthly field sampling indicated that S. hineana use open channel areas in spring and early summer moving into burrow systems in mid summer when channel areas normally dry. Laboratory experiments and field observations confirmed that crayfish prey on S. hineana larvae. Adult crayfish were a larger predation threat than juvenile crayfish. Despite their negative predatory impact, removal of crayfish from burrows in the field did not enhance densities of S. hineana larvae. Although S. hineana may face the threat of predation in burrows, they face a greater risk of desiccation if they remain in the open channel. These results lead to the counterintuitive conclusion that the maintenance of a predator is important for conserving an endangered prey species.  相似文献   

13.
The distribution of the soil borne fungal population in maize non-rhizospheric soil in experimental trials were studied during the harvest seasons 2000/2001 and 2001/2002. The effect of different tillage practices was evaluated. Soil samples were collected from three tillage treatments, conventional tillage, reduced tillage and no tillage, with and without grazing. The distribution of fungal propagules in different treatments was compared. Soil samples were collected from the top soil (3 cm) before planting, in the sprong. No tillage without grazing and reduced tillage with grazing had the highest densities of filamentous fungi (5.71 and 5.85 log, respectively). The mycological survey showed the presence of six genera of filamentous fungi. They were Aspergillus, Fusarium, Penicillium, Trichoderma, Cladosporium, Alternaria. The species identified from genus Aspergillus were A. flavus, A. restrictus, A. candidus, A. parasiticus and other Aspergillus spp. The species identified from genus Penicillium were P. pinophylum, P. citreonigrum, P. implicatum, P. purpurogenum, P. minioluteum, P. waksmanii, P. restrictum, P. rugulosum, P. funiculosum and P. variabile. Species from genus Fusarium were identified as F. verticillioides, F. oxysporum, F. proliferatum and others Fusarium species. The isolation frequency of Aspergillus increased in the no tillage and grazing practices treatments. The data indicate that different agricultural practices impact soil inocula of principal maize toxigenic fungi in the production area. To our knowledge, this is the first report on the effect of tillage management practices on fungal populations in preharvest maize agroecosystem in Argentina.  相似文献   

14.
黄秋葵(Hibiscus esculentus L.)纤维素和木质素的大量积累极易引起果实老化,而植物MYB转录因子参与纤维素和木质素等生物合成与沉积,在次生细胞壁形成中起着重要的调控作用。为研究MYB转录因子在黄秋葵老化中的作用,从黄秋葵果实转录组测序数据库中筛选得到10条功能注释为MYB基因的片段序列,克隆获得了HeMYB4、HeMYB6、HeMYB26、HeMYB28、HeMYB44、HeMYB46、HeMYB59、HeMYB86、HeMY108和HeMYB113的基因全长,分析其核苷酸及编码氨基酸序列特征,同时进行了亚细胞定位、磷酸化位点、功能域、进化等生物信息学分析。结果显示,10个MYB基因均定位于细胞质膜上,具有丰富的磷酸化位点和功能域,与拟南芥等物种中参与纤维素和木质素合成的MYB蛋白亲缘关系较近。通过实时荧光定量PCR分析黄秋葵MYB基因家族的10个基因在果实发育过程、采后常温贮藏期间的表达,结果发现,HeMYB46、HeMYB86、HeMY108的表达量与纤维素含量呈极显著正相关,推测上述基因在黄秋葵果实衰老过程纤维素合成中起重要作用;HeMYB46、HeMYB59的表达量与木质素含量呈极显著正相关,推测其在木质素合成中起到重要调控作用。本研究结果初步明确了黄秋葵MYB转录因子在黄秋葵老化过程中的作用, 为黄秋葵的生产、分子育种等提供了理论基础。  相似文献   

15.
We examined the effect of plant diversity on plant production and soil macrofauna density and diversity. Four plants species (Arachis pintoi, an herbaceous legume; Brachiaria brizantha, a perennial grass; Leucaena leucocephala, a legume shrub; Solanum rugosum, a non-legume shrub) were used in a field experiment and communities of all combinations of one, two, three or four species were established. Plant diversity neither significantly affected density and diversity of soil macrofauna nor total plant biomass, however, the biomass of specific plants was negatively affected by plant diversity. Earthworm and ant densities were significantly higher in the presence of A. pintoi although this plant influenced neither the density of the other group nor fauna diversity. Earthworm and diplopod densities increased significantly with shoot biomass of A. pintoi. Fauna diversity increased significantly with shoot biomass (specific and total). Root biomass did not affect fauna density and diversity. Our results suggest that fauna density is affected by litter quality and that it is more affected by resource quantity than quality. Our results also confirm the importance of nitrogen fixers to ecosystem function.  相似文献   

16.
水生观赏植物对城市污水的修复研究   总被引：2，自引：0，他引：2  
将黄花鸢尾、石菖蒲、菖蒲、千屈菜、泽泻、玉带草6种水生观赏植物种植于模拟人工湿地系统中,对城市污水进行绿色修复研究。分别在第5天、第10天、第15天测定污水中总氮（TN）、总磷（TP）、化学需氧量（COD）、生化需氧量（BOD5）、重金属元素（Cr,Pb,Cd）的含量,研究水生观赏植物对城市污水的处理效果和修复能力。结果表明:各植物系统对TN,TP,COD,BOD5以及重金属Cr,Pb,Cd去除效率随时间的推移逐渐上升,至第15天去除效率分别达88.1%,95.9%,90.6%,86.7%,78.1%,83.2%,91.4%以上。各植物系统对各种污染物的去除效率呈现一定差异,处理时间的不同对植物的修复效果也存在一定影响。6种水生观赏植物中,综合净化能力以黄花鸢尾和石菖蒲最为突出,是值得推荐的城市污水修复植物。  相似文献   

17.
MAP65-3是植物胞质分裂的重要调节因子。为探究水稻OsMAP65-3基因的功能,本研究采用CRISPR/Cas9技术对水稻中OsMAP65-3基因(OsMAP65-3.1和OsMAP65-3.2)进行编辑。针对每个基因各设计了2个不同的靶位点,并将OsMAP65-3.1与OsMAP65-3.2的靶位点放在同一个载体上,构建了CSMAP65-3A和CSMAP65-3B 2个双基因编辑载体。通过农杆菌介导的遗传转化分别获得17和21个植株,PCR鉴定阳性植株分别为16和20株。对T0代植株靶位点附近序列进行测序分析,结果表明OsMAP65-3s基因均被成功编辑,OsMAP65-3.1 2个位点编辑效率为17.50%和9.38%,OsMAP65-3.2 编辑效率为15.62%和45.00%;T0代已获得osmap65-3.2、osmap65-3.2/OsMAP65-3.1(+/-)和OsMAP65-3.2(+/-)/OsMAP65-3.1(+/-)材料。本研究为进一步创制OsMAP65-3s突变体,开展基因功能研究和水稻胞质分裂分子机制解析奠定了理论基础。  相似文献   

18.
Ferralsols under native vegetation have a weak to moderate macrostructure and a well-developed microstructure corresponding to subrounded microaggregates that are usually 80 to 300 μm in size. The aim of this study was to analyze how the hydraulic properties of a clay Ferralsol were affected by a change of structure when the native vegetation is cleared for pasture. We studied the macrostructure in the field and microstructure in scanning electron microscopy. The water retention properties were determined by using pressure cell equipment. We determined the saturated hydraulic conductivity, Ks, by applying a constant hydraulic head to saturated core samples, and the unsaturated hydraulic conductivity, K(Ψ), by applying the evaporation method to undisturbed core samples. Results showed a significant decrease in the water retained at −1 and −10 hPa from 0- to 40-cm-depth when the native vegetation is cleared for pasture. That decrease in the water retained was related to a smaller development of microaggregation and greater proportion of microaggregates in close packing. For smaller water potential, there was no difference of water retained at every depth between native vegetation and pasture. Pedotransfer functions established earlier for Brazilian Ferralsols and using clay content as single predictor gave pretty good results but the precision of the estimation decreased when the water potential increased. This decrease in the precision was related to the lack of predictor taking structure into account. Ks and K(Ψ) showed an upward trend with depth under native vegetation and pasture. Except at 0–7-cm depth between the Brachiaria clumps in the pasture where smaller Ks and K(Ψ) than at the other depth was recorded whatever land use, we did not record any significant difference of Ks and K(Ψ) at every depth between native vegetation and pasture. The upward trend shown by the hydraulic conductivity with depth was related to the increase in the development of microaggregation with depth.  相似文献   

19.
磷酸二酯酶(PDE)能够特异地催化cAMP/cGMP 3', 5'环磷酸的3'环磷酸键水解,调节胞内cAMP水平,进而调控致病真菌的生长发育,但PDE基因在梨果黑斑病菌中的具体调控机制有待研究。本研究采用反转录PCR(RT-PCR)克隆了梨果黑斑病菌Alternaria alternata中的PDEL和PDEH基因;通过TMHMM、ProtScale、SOPMA等在线分析工具对AaPDEL和AaPDEH基因及其编码蛋白进行生物信息学分析;采用实时荧光定量PCR(qRT-PCR)技术分析了PDEL和PDEH基因在梨果黑斑病菌侵染结构分化过程中的表达特性。克隆得到梨果黑斑病菌PDEL和PDEH,分别命名为AaPDEL和AaPDEH,蛋白编码区(CDS)长度分别为3 132和2 886 bp,分别编码1 043和961个氨基酸。生物信息学分析表明AaPDEL和AaPDEH均属于不稳定亲水蛋白,不含信号肽也无跨膜结构,均具有多个磷酸化位点,分别定位于线粒体和细胞核上;AaPDEL和AaPDEH分别具有Class Ⅱ型和Ⅰ型保守催化结构域。系统分析结果表明,AaPDEL和AaPDEH与小麦褐斑病菌(Pyrenophora tritici-repentis)和番茄匍柄霉(Stemphylium lycopersici)亲缘关系最近,同源性分别高达79.25%和88.80%。qRT-PCR结果显示,疏水性诱导,A. alternata侵染结构分化过程中,AaPDEL和AaPDEH基因在附着胞形成阶段(6 h)表达量显著提高,较萌发初期阶段(2 h)分别上调1.19和1.97倍,表明AaPDEL和AaPDEH在A. alternata侵染结构分化中具有重要的调控作用。本研究为进一步从分子水平揭示PDE调控机制奠定了基础。  相似文献   

20.
番茄八氢番茄红素合成酶(SlPSY1)作为类胡萝卜素生物合成途径的关键限速酶,直接影响果实中类胡萝卜素的积累。为探究SlPSY1基因的转录调控机制,通过克隆SlPSY1基因启动子序列,构建pSlPSY1pro-AbAi诱饵载体,并将诱饵载体转化至酵母细胞中获得诱饵酵母菌株。利用番茄混合组织酵母杂交cDNA文库进行酵母单杂交筛库试验,筛选得到AP2/ERF家族转录因子SlJERF1和10个未知功能蛋白。后续克隆SlJERF1基因序列,构建pGADT7-SlJERF1重组载体,通过酵母单杂交点对点对SlJERF1进行分子验证,结果显示在金担子素(AbA)浓度为150 ng·mL-1的条件下,对照组酵母不能正常生长,而试验组酵母能正常生长,表明SlJERF1与SlPSY1基因启动子存在互作。这一结果为进一步拓展类胡萝卜素合成调控网络提供了重要的理论依据。  相似文献   

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