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1.
Populations of the obligate-seeder, Banksia ericifolia, were even-aged. Seedling recruitment occurred only after fire. Mean genet size (height + canopy diameter; H+D) increased progressively with elapsed time since fire in stands last burnt 2–23 years before 1981. Populations of a co-occurring resprouter, B. oblongifolia, were mixed-aged. Genet size varied significantly between stands, but this variation was not explained by regressions of H+D on years since fire. In addition B. oblongifolia seedlings were recruited both after fire and in patches of heath unburnt for 16 years.Most flower and seed production in B. oblongifolia occurred in the stands last burnt less than 10 years previously. More than 30% of genets had not produced cones since the last fire, irrespective of how many years had elapsed. In contrast, few B. ericifolia genets had produced cones five years after fire, but by 16 years after fire nearly 100% had. Overall, about 51% of B. ericifolia inflorescences and about 28% of B. oblongifolia inflorescences set seed. The number of seeds in seed-bearing cones was not significantly different between species.Resprouting B. oblongifolia genets began flowering sooner after fire, but B. ericifolia subsequently overtook them in accumulating a bank of serotinous seeds. In the stand unburnt for 23 years the largest B. ericifolia genets had more than twice as many cones as the largest co-occurring B. oblongifolia. However, when accumulated cone production was compared for genets of equal H+D over all stands, there was no difference between species.We thank the New South Wales National Parks & Wildlife Service for permission to do this work in Ku-ring-gai Chase National Park. We are grateful to Don Adamson, Lynn Day, David Haig and James Sim for constructive comments on earlier drafts.  相似文献   

2.
A non-systemic Insecticide was used to exclude flower and seed predators from Banksia ericifolia and B. oblongifolia Inflorescenses. In B. ericifolia this treatment doubled the number of inflorescences that set seeds, and increased by 40% the number of seeds produced per Inflorescence. Insecticide treatment did not alter either of these components of seed-set in B. oblongifolia partly because the experiment began too late to exclude flower predators In this species. The results obtained for B. ericifolia support the hypothesis that flower and seed predators explain, in part, the low incidence of seed-bearing cones and the low seed:flower ratios reported for many Banksia species. Each Banksia species supports two guilds of Inflorescence predators. Two Lepidopteran species feed on young flowers; one of these causes tunnel damage to the rachis. Each Banksia species also supports five Lepidopteran and two Curcullonid seed-predators. About 40% of these herbivorous Insects are common to both shrubs.  相似文献   

3.
We developed 11 polymorphic microsatellite DNA markers for an Australian native shrub Banksia hookeriana (Proteaceae). The number of alleles per locus in 37 individuals varied from three to 17, observed and expected heterozygosities ranged from 0.297 to 0.838 and from 0.279 to 0.900, respectively. Two loci (BH‐B5 and BH‐B107) showed significant deviation from Hardy–Weinberg equilibrium (P < 0.05), and null alleles may be present at these two loci. All loci showed independent inheritance.  相似文献   

4.
The consequences of observed variations in pollinator activity for plant reproduction depend on the breeding system of the plant and also on whether pollination is a resource in short supply. These factors are frequently assumed rather than tested. In bagging experiments with Banksia paludosa in heath and B. spinulosa var. spinulosa in woodland, the present study demonstrated that seed-set does not occur by autogamy and that pollinators are indeed necessary. Experimental addition of outcrossed pollen to inflorescences failed to produce any increase in the mean number of seeds per inflorescence, measured for non-barren inflorescences, for either species. However, in B. paludosa, the addition of pollen increased the numbers of inflorescences that set seed from 20% (controls) to 45% (pollen-added treatment). This suggests either unusual patterns of pollen movement among and within plants or control of the pattern of seed-set within a plant. Pollen additions failed to alter seed-set in B. spinulosa. It is possible that a greater abundance of pollinators in the woodland ensures adequate pollination for these plants  相似文献   

5.
We carried out DNA barcoding on 24 Korean tettigonid species of 19 genera deposited in the National Institute of Biological Resources to reevaluate the preliminary identification of each specimen. Sequence divergence of DNA barcodes obtained from 113 samples of the 24 species ranged from 0 to 30.4%, the intraspecific variation was 0–7.3%, and the interspecific divergence was 1.1–30.4%; we could not examine the barcoding gap. In the neighbor‐joining tree, the branch length among individuals of Tettigonia ussuriana, Paratlanticus ussuriensis, and Hexacentrus japonicus were relatively longer than those in other species. The detailed analysis of the morphological characters and DNA barcodes of the above three species revealed that these three species represent species complexes. The T. ussuriana complex comprised T. jungi, T. uvarovi, and T. ussuriana. Paratlanticus ussuriensis cluster contained four species; one cluster was identified as P. palgongensis based on morphological characteristics, but the other three clusters, including the P. ussuriensis cluster, require further detailed taxonomic analysis. Lastly, two species clusters were identified within the Hexacentrus japonicus clade. Based on the 99% sequence similarity obtained by blast search of the NCBI GenBank database, one of the clusters was identified as H. unicolor. Thus, the DNA barcoding revealed the presence of at least three cryptic species in Korean Tettigoniidae, although more detailed taxonomic analyses are required to establish their status. Therefore, we suggest that DNA barcoding is a very useful tool for increasing the identification accuracy of insect collections.  相似文献   

6.
The Banded Iron Formations (BIFs) of south‐western Australia are terrestrial islands characterized by high species richness and endemism. Regional endemics occur across multiple formations without inhabiting the intervening landscape matrix. We investigated whether the occurrence on BIF terrestrial islands has led to genetic differentiation among the eight known populations of the regional endemic, Banksia arborea. Genetic structure was assessed using three chloroplast DNA sequence markers and 11 nuclear microsatellite loci. Phylogenetic relationships were assessed with statistical parsimony and Bayesian methods. Dates of haplotype divergence were estimated using the time to most recent common ancestor of B. arborea and Banksia purdieana, as well as a conservative angiosperm chloroplast (cp)DNA mutation rate. Population genetic diversity and structure was assessed amongst and within populations by genotyping 24 geographically clustered individuals from each BIF and three subpopulations within the Die Hardy Range BIF. Indirect gene flow estimates were determined using a method based on the frequency of private alleles. Banksia arborea showed low genetic diversity in (cp)DNA and a complex structural pattern, with genetic differentiation of some BIF populations and an absence of differentiation amongst others, reflecting either retention of ancestral polymorphism across northern BIF populations or more recent connectivity of these populations. There was little evidence of pollen dispersal both between BIFs and within the large BIF known as Die Hardy Range. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114 , 860–872.  相似文献   

7.
蔡磊  BORAH Dipankar  刀志灵  温放 《广西植物》2020,40(10):1402-1408
通过查阅相关文献和标本,作者发现近期发表的苦苣苔科吊石苣苔属植物一新种——Lysionotus bijantiae D. Borah & A. Joe实为鉴定错误,应是汉克苣苔属的长圆叶汉克苣苔[Henckelia oblongifolia(Roxb.)D. J. Middleton & Mich. Möller] [原长圆叶唇柱苣苔Chirita oblongifolia(Roxb.)Sinclair]。Lysionotus bijantiae的模式标本采集于中国西藏东南部地区的喜马拉雅南坡,该地区苦苣苔植物多样性较为丰富。作者因其花具2枚发育雄蕊而将其归于吊石苣苔属,花萼分裂不达基部而与吊石苣苔属其他相关种类比较,而忽略了其种子先端不具附属物的特征。通过电镜扫描观察到,该种在墨脱境内居群以及其模式产地居群的种子均无附属物,从而证实了该种不是吊石苣苔属的物种,而是属于汉克苣苔属。因此,作者将Lysionotus bijantiae处理为Henckelia oblongifolia的新异名,同时提供了长圆叶汉克苣苔的彩色图片(含种子扫描图)、选定模式标本,并给出了吊石苣苔属和汉克苣苔属的区分方法和主要识别特征,不仅为这两个属的物种鉴定提供了参考,而且避免更多的物种分类混淆问题出现。  相似文献   

8.
We developed 11 polymorphic microsatellite DNA markers for an Australian native shrub Banksia attenuata. The number of alleles per locus in 50 individuals varied from five to 18, observed and expected heterozygosities ranged from 0.300 to 0.740 and from 0.537 to 0.918, respectively. Six loci showed no significant deviation from Hardy–Weinberg equilibrium (P > 0.05), and null alleles appear to exist at locus BA‐B1. All loci showed independent inheritance.  相似文献   

9.
1. Mutualisms are relationships of mutual exploitation, in which interacting species receive a net benefit from their association. In obligate pollination mutualisms (OPMs), female pollinators move pollen between the flowers of a single plant species and oviposit eggs within the female flowers that they visit. 2. Competition between co‐occurring pollinator species is predicted to increase pollinator virulence, i.e. laying more eggs or consuming more seeds per fruit. Plants involved in OPMs frequently host various non‐pollinating seed parasites and parasitoids that may influence the outcome of the mutualism. Quantifying the prevalence of parasites and parasitoids and competition between pollinators is important for understanding the factors that influence OPM evolutionary stability. 3. This study investigated the pollination mutualism occurring between the leaf flower plant, Breynia oblongifolia, and its co‐pollinating Epicephala moths. A third moth, Herpystis, also occurs in B. oblongifolia fruits as a non‐pollinating seed parasite. 4. Breynia oblongifolia fruits were collected to quantify seed predation and compare seed predation costs between the three moth species. Results showed that the larvae of the two pollinator species consume similar numbers of seeds, and that adults deposit similar numbers of eggs per flower. As such, no evidence of increases in virulent behaviours was detected as a result of competition between co‐pollinators. 5. By contrast, the seed parasite Herpystis consumed more seeds than either pollinator species, and fruit crops with a high proportion of Herpystis had significantly lower net seed production. 6. This work adds to the growing understanding of the ecology and dynamics of plant–pollinator mutualisms.  相似文献   

10.
11.
Using randomly amplified polymorphic DNA markers (RAPD), genetic variation and differentiation in four populations of pedunculate oak Quercus robur L. were examined. The populations occupy a large part of the Quercus robur range in the European Russia (Voronezh and Novgorod oblasts; Republics of Mordovia and Bashkortostan). With each of six random primers (A02, A09, A17, B01, B08, B11), 96 DNA samples were analyzed by PCR. In all, 48 putative polymorphic RAPD loci were detected. We failed to reveal population-specific DNA fragments for any primer although the frequencies of 14 fragments were significantly different among populations. The oak populations studied exhibited high variability: 73–90% of genes were polymorphic and the effective allele number was about 1.4. The total genetic variation varied from 0.202 (Vor) to 0.245 (Nov), which corresponded to the estimates for populations of this species from Central and Western Europe. The populations examined showed low among-population differentiation (G ST = 0.098); gene flow N e m was 4.61. The proportion of among-population variation of the RAPD loci studied accounted for 7% of the total variability; more than 93% of the total variability was explained by individual and within-population variation.  相似文献   

12.
In three experimental sites in Southern Hesse, differing in management procedures, one- to three-year-old saplings of Quercus robur, Q.pubescens, and Q.ilex were planted to study their performance under Central European climate conditions. Toward the end of the growth period (mid–late September 2011), during a very dry period, we measured JIP transients of photosystem II chlorophyll fluorescence induction curves to evaluate the effects of abiotic site factors on the photosynthetic apparatus by comparing them to data from well-watered saplings measured before the onset of senescence processes. In all three sites, Q. robur saplings in September showed the strongest deviation from the measurements in August, followed by Q. pubescens. Q. ilex, in general, was nearly unaffected by September climate conditions or performed better than plants measured in August. Differences in the behavior between species and sites could be explained by the species’ different drought susceptibility and by differential induction of early leaf senescence (in Q. robur and Q. pubescens). We conclude that measurement of the JIP transient is a feasible method in forestry to compare adverse microclimatic site effects and genetically fixed reactions of the photosynthetic apparatus in the field.  相似文献   

13.
Question: Does the introduced pathogen Phytophthora cinnamomi change Banksia woodland α‐ or β‐diversity and what are the implications for species re‐colonization? Location: High rainfall zone of the Southwest Australian Floristic Region (SWAFR). Methods: We measured pathogen‐induced floristic change along a disease chronosequence, and re‐sampled historic quadrats in Banksia attenuata woodlands of the SWAFR. The chronosequence represents three disease stages: (1) healthy vegetation with no disease expression; (2) the active disease front; and (3) diseased vegetation infected for at least 15 years. Comparative data were obtained by resampling diseased plots that were historically disease‐free when established in 1990. Results: β‐diversity differed substantially for both chronosequence and historic data, while α‐diversity was maintained, as measured by plot species richness and Simpson's reciprocal index. Species of known pathogen susceptibility were significantly reduced in cover–abundance, including the structurally dominant species; Banksia attenuata, B. ilicifolia and Allocasuarina fraseriana. Although these species remained present on diseased sites, there were overall reductions in canopy closure, leaf litter and basal area. These declines were coupled with an increase of species with unknown susceptibility, suggesting potential resistance and capacity to take advantage of altered site conditions. Conclusions: This study highlights the ability of an introduced plant pathogen to alter community floristics and associated stand variables. Species cover–abundances are unlikely to recover due to a reduced seed source, altered site conditions and pathogen persistence at the landscape level. However, maintenance of α‐diversity suggests continued biological significance of Phytophthora‐affected sites and the formation of novel ecosystems, themselves worthy of conservation.  相似文献   

14.
Eight polymorphic microsatellite loci are described for the Iberian rock lizard species, Iberolacerta cyreni. Loci were isolated from a partial genomic library that had been enriched for AAAG repeat sequence. Number of alleles per locus ranged from two to 13 in a sample of 24 individuals from the Sierra de Guadarrama (central Spain). Observed heterozygosity ranged from 0.13 to 0.96. At least three loci were amplified and polymorphic in four other Iberian rock lizard species: Iberolacerta monticola, Iberolacerta bonnali, Iberolacerta aranica and Iberolacerta aurelioi. These markers will be used to study mating strategies and reproductive success in I. cyreni.  相似文献   

15.
Elevated substrate salinity and anthropogenic impulse are the major threat to the mangrove ecosystem. In the Indian subcontinent, Sundarbans have the richest mangrove species diversity. Due to geomorphic characteristics and unplanned management, the elevated salinity prevails in the western part and that has direct impact on vegetation. Seven mangrove taxa were examined, of which four (Aegialitis rotundifolia, Heritiera fomes, Xylocarpus granatum, and X. mekongensis) were considered as degrading and three (Bruguiera gymnorrhiza, Excoecaria agallocha, and Phoenix paludosa) were considered as natural control. The targeted taxa were collected from five different islands and were selected on the basis of increasing salinity gradient. As salinity increased from site I to V (11.76–15.2 ppt), the amount of total leaf proteins decreased in all the targeted species and ranged between 5.67 and 25.23%. The percentage of protein depletion was less in Aegialitis, Heritiera, and Xylocarpus than the other three taxa in higher salinity that pointed out their less adaptability, as degradation of protein may be essential for efficient stress management. Two antioxidative (peroxidase and superoxide dismutase) and two hydrolyzing (acid phosphatase and esterase) enzymes showed a positive correlation with salinity. In four degrading taxa, the percentage of enzyme increment was less than those of their natural control taxa. Salinity imposed increment of antioxidant enzymes facilitate ROS scavenging, which is an inevitable elevated byproduct during photo-inhibition. Lower amount and number of isoforms in higher salinity indicated towards less suitability of Aegialitis rotundifolia, Heritiera fomes, Xylocarpus granatum, and X. mekongensis in increased salinity level of western Sundarbans.  相似文献   

16.
Abstract One application of DNA barcoding is species identification based on sequences of a short and standardized DNA region. In plants, various DNA regions, alone or in combination, have been proposed and investigated, but consensus on a universal plant barcode remains elusive. In this study, we tested the utility of four candidate barcoding regions (rbcL, matK, trnHpsbA, and internal transcribed spacer (ITS)) as DNA barcodes for discriminating species in a large and hemiparasitic genus Pedicularis (Orobanchaceae). Amplification and sequencing was successful using single primer pairs for rbcL, trnH‐psbA, and ITS, whereas two primer pairs were required for matK. Patterns of sequence divergence commonly showed a “barcoding gap”, that is, a bimodal frequency distribution of pairwise distances representing genetic diversity within and between species, respectively. Considering primer universality, ease of amplification and sequencing, and performance in discriminating species, we found the most effective single‐region barcode for Pedicularis to be ITS, and the most effective two‐region barcode to be rbcL + ITS. Both discriminated at least 78% of the 88 species and correctly identified at least 89% of the sequences in our sample, and were effective in placing unidentified samples in known species groups. Our results suggest that DNA barcoding has the potential to aid taxonomic research in Pedicularis, a species‐rich cosmopolitan clade much in need of revision, as well as ecological studies in its center of diversity, the Hengduan Mountains region of China.  相似文献   

17.
Plant adaptation to an environment subject to heavy snowfalls was investigated in four species of evergreen shrubs growing in a Fagus crenata forest in an area of Honshu on the Sea of Japan. These shrubs stored carbohydrates in some organs before the snowy season and were covered with snow for 4–5 months. Aucuba japonica var. borealis, Camellia rusticana, and Ilex crenata var. paludosa maintained a reserve of carbohydrates during the snowy season. In Daphniphyllum macropodum var. humile, the reserve of carbohydrates decreased during winter. The respiration rates in the first three species decreased from autumn to winter, whereas the decrease in D. macropodum was slight. It was found that the first three species could use reserve carbohydrates for the growth of new shoots after the thaw, whereas in the last species the growth of new shoots depends on high photosynthetic activity in late spring. Our findings suggest some types of matter economy in evergreen shrubs for wintering in an environment of heavy snow.  相似文献   

18.
The worldwide decline and local extinctions of bumblebees have raised a need for fast and accurate tools for species identification. Morphological characters are often not sufficient, and molecular methods have been increasingly used for reliable identification of bumblebee species. Molecular methods often require high‐quality DNA which makes them less suitable for analysis of low‐quality or older samples. We modified the PCR–RFLP protocol for an efficient and cost‐effective identification of four bumblebee species in the subgenus Bombus s. str. (B. lucorum, B. terrestris, B. magnus and B. cryptarum). We used a short partial mitochondrial COI fragment (446 bp) and three diagnostic restriction enzymes (Hinf I, Hinc II and Hae III) to identify species from degraded DNA material. This approach allowed us to efficiently determine the correct species from all degraded DNA samples, while only a subset of samples 64.6% (31 of 48) resulted in successful amplification of a longer COI fragment (1064 bp) using the previously described method. This protocol can be applied for conservation and management of bumblebees within this subgenus and is especially useful for fast species identification from degraded samples.  相似文献   

19.
In this study, we present the detailed molecular investigation of the ectomycorrhizal (ECM) community of Quercus petraea and Quercus robur seedlings grown in bare-root forest nurseries. In all tested oak samples, mycorrhizal colonization was nearly 100%. Morphological observation and molecular investigations (sequencing of fungal ITS rDNA) revealed a total of 23 mycorrhizal taxa. The most frequent and abundant fungal taxa were Hebeloma sacchariolens, Tuber sp., and Peziza sp.; from the detected fungal taxa, 20 were noted for Q. petraea and 23 for Q. robur. Depending on the nursery, the species richness of identified ECM fungal taxa for both oak species ranged from six to 11 taxa. The mean species richness for all nurseries was 5.36 and 5.82 taxa per Q. petraea and Q. robur sample, respectively. According to the analysis of similarity, ECM fungal communities were similar for Q. petraea and Q. robur (R = 0.019; p = 0.151). On the other hand, detected fungal communities were significantly different between nurseries (R = 0.927; p < 0.0001). Using the Spearman rank correlation, it was determined that the ectomycorrhizal diversity (in terms of richness, the Shannon diversity, evenness, and Simpson dominance indices) is significantly related to the soil parameters of each nursery. We conclude that individual nursery may be considered as separate ecological niches that strongly discriminate diversity of ECM fungi.  相似文献   

20.
Carpinus oblongifolia is an endemic species and the extant wild populations show a fragmentation distribution in the Baohua Mountain of Jiangsu Province in eastern China. Understanding of genetic diversity plays an important role in C. oblongifolia survival and sustainable development. The wild C. oblongifolia population was artificially divided into four subpopulations according to the microhabitats, and another two subpopulations were constructed by progeny seedlings cultivated with the mature seeds. Then, the leaf buds of 80 individuals from six subpopulations were sampled to develop single nucleotide polymorphisms (SNPs) using specific-locus amplified fragment sequencing (SLAF-seq). Based on these SNPs, we aimed to characterize the genetic diversity and population structure of C. oblongifolia and provide an illumination and reference for effective management of such a small endemic population. The level of genetic diversity was low at the species level, and the progeny subpopulations had a relatively higher genetic diversity than the wild subpopulations. This may be attributed to a high gene flow and an excess heterozygosity to reduce the threat of genetic drift-based hazards. Moreover, the progeny subpopulations had the ability to form new clusters and a great contribution to the genetic structure variation of C. oblongifolia. These results will assist with the development of conservation and management strategies, such as properly evacuating competitive trees to provide more chance for pollen and seed flow in situ conservation, and establishing sufficient seedling plantlets under laboratory conditions for reintroduction to enlarge the effective population size.  相似文献   

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