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1.
Hawthorn (Crataegus spp.) is an edible wild fruit that is used in traditional medicine, landscape studies, and food and beverage industries in many countries. It is an important wild plant species in Turkey and is numerous in the Yozgat Province. Genetic and breeding studies on hawthorn are very limited. Therefore, we aimed to characterize 91 hawthorn genotypes using simple sequence repeat (SSR) markers. The SSRs were developed from apple and pear and were screened in hawthorn for amplification and polymorphisms. A total of 265 alleles were detected from thirty-two SSR primer pairs, and those were used to identify genetic relationships. The number of alleles ranged from 2 to 21 alleles per locus with a mean value of 8.28. The Hi05b09 locus showed the highest allele number (Na?=?21). The polymorphism information content (PIC) values ranged from 0.16 (CH03d10) to 0.89 (C6554) with a mean value of 0.60. An Unweighted Pair Group Method with Arithmetic Average method was used to cluster the genotypes, and four major clusters were obtained from the amplification of the SSRs. STRUCTURE software identified four populations (ΔK?=?4) and eight sub-populations (ΔK?=?8), and four major clusters similar results to UPGMA analysis. Our study showed that the SSR markers could be utilized as a reliable tool for the determination of genetic variations and relationships of hawthorn genotypes. A basic molecular analysis on the hawthorn genotypes identified in this study will promote the collection of germplasm collection and the selection of parents’ in future cross-breeding studies.  相似文献   

2.
Five species of larval parasitoids were reared fromRhagoletis pomonella (Walsh) infested fruit of hawthorn,Crataegus, collected from several locations in southwest Washington over a four year period. A braconid,Biosteres melleus (Gahan), parasitized larvae infesting fruits of a native hawthorn species,Crataegus douglasii Lindl. Another braconid,Opius downesi Gahan, emerged exclusively fromR. pomonella pupae reared from fruits of an introduced species of hawthorn,Crataegus monogyna Jacq. A pteromalid,Pteromalus sp., and two eulophids,Tetrastichus spp., attackedR. pomonella larvae infesting fruits of both hawthorn species. No parasitoids emerged from a total of 4385 pupae reared from apple. Percent parasitism ofR. pomonella was higher inC. monogyna compared toC. douglasii fruits. The highest average levels of parasitism ofR. pomonella inC. monogyna andC. douglasii fruits were 90% and 23% respectively. The kinds of parasitoids, their relative abundances and timing of parasitization on the two hawthorns was related to differences in fruit ripening patterns and its effect on the development ofR. pomonella on these two hosts. Parasitization ofR. pomonella byTetrastichus spp. is a new host record. The detection of these species andPteromalus sp. in southwest Washington are the first records of ectoparasitoids attacking this tephritid.  相似文献   

3.
I did the food habits of the Asiatic black bear Ursus thibetanus from 1013 fecal samples collected between 1999 and 2005 in the Misaka Mountains on the Pacific coast of central Japan. The food habits of the bears showed clear seasonal changes, and I classified the food resources of the bears into three types. Staple foods were green vegetation in spring, soft mast (Prunus spp.) and insects in summer, and hard mast (Quercus spp.) in autumn. Alternative foods were green vegetation and other soft mast (Rubus spp.) in summer and Japanese chestnuts Castanea crenata and vine fruits in autumn. Foods of opportunity were hard mast (Quercus spp.) that had been shed in the previous autumn and were found in spring and other fruits in autumn. Seasonal food habits showed yearly variations: bears used alternative foods and foods of opportunity in response to the yearly variation in staple food amount, but the magnitude of variability of food habits differed among seasons, with large variability in autumn and small variability in summer and spring. The primary influence on the yearly variation in food habit is presumably the fluctuation in fruit production among years. Summer is probably the most difficult season in terms of the bear's food supply, because the number of fruiting species is limited and staple foods such as new green vegetation and fruits are less available. Long-term studies of the availability of the main food items and food habits of bears will be critical for further understanding these animals’ feeding ecology and for determining the factors that influence their behavior.  相似文献   

4.
Stable nitrogen isotope ratios have been used to study the incorporation of nitrogen into the food webs of marine systems. Some species of algae can be cocultured with shrimp, resulting in a sustainable alternative to reduce or eliminate the use of commercial food. One option is the development of Ulva spp. in open-air ponds under a rigorous control of water quality. Recently, the coculture of Ulva spp. and juvenile shrimp (in aquaria and open-air ponds) has shown, under stereomicroscope observation, that the crustaceans were feeding on the Ulva spp. The consumption of commercial food and Ulva spp. by juvenile shrimp has been evaluated to establish the uptake of nitrogen into tissues of this crustacean. The muscle tissue of juvenile shrimp initially assimilated nitrogen from commercial feed and later the cocultured shrimp assimilated nitrogen from the Ulva spp., which demonstrated the potential application of live and fresh diets and the optimization of their use in diets containing very low levels or no commercial food.  相似文献   

5.
Data on the composition of flavonoids in the Chenopodium L. species of world flora and the available information on their biological activity are given. The main flavonoids of fat-hens are 3-O-glycosides of caempferol, quercetin, and isoramnetin. Flavones are characteristic of some species. The Chenopodoum species are also characteristic of some species. The Chenopodium spp. are interesting as a source of raw material containing flavonoids.  相似文献   

6.
Capuchin monkeys (Cebus spp. and Sapajus spp.) and coatis (Nasua spp.) coexist in most neotropical forests, including small forest remnants. Both capuchins and coatis eat fruit and disperse seeds, but little is known about whether their roles in seed dispersal are redundant or complementary. We compiled 49 studies from the literature on feeding by capuchins and/or coatis, of which 19 were comprehensive enough for our analyses. We determined the relative importance of fruit eating to each species and compared their diets. Additionally, we analysed the structure of three fruit–frugivore networks built with both animal groups and the fruits they eat and evaluated whether fruit traits influenced the network topology. Fruits represented the largest part of capuchin and coati diets, even though coatis have been known for their opportunistic and generalist diets. Capuchins and coatis also exhibited similar general diet parameters (niche breadth and trophic diversity). The three networks exhibited high connectance values and variable niche overlap. A Multiple Correspondence Analysis, failed to detect any trait or trait combination related to food use. In conclusion, capuchins and coatis both have generalist diets; they feed on many different species of fruits and exhibit important complementarity as seed dispersers. Both are likely to be particularly important seed dispersers in disturbed and fragmented forests.  相似文献   

7.
Taxa harboring high levels of standing variation may be more likely to adapt to rapid environmental shifts and experience ecological speciation. Here, we characterize geographic and host‐related differentiation for 10,241 single nucleotide polymorphisms in Rhagoletis pomonella fruit flies to infer whether standing genetic variation in adult eclosion time in the ancestral hawthorn (Crataegus spp.)‐infesting host race, as opposed to new mutations, contributed substantially to its recent shift to earlier fruiting apple (Malus domestica). Allele frequency differences associated with early vs. late eclosion time within each host race were significantly related to geographic genetic variation and host race differentiation across four sites, arrayed from north to south along a 430‐km transect, where the host races co‐occur in sympatry in the Midwest United States. Host fruiting phenology is clinal, with both apple and hawthorn trees fruiting earlier in the North and later in the South. Thus, we expected alleles associated with earlier eclosion to be at higher frequencies in northern populations. This pattern was observed in the hawthorn race across all four populations; however, allele frequency patterns in the apple race were more complex. Despite the generally earlier eclosion timing of apple flies and corresponding apple fruiting phenology, alleles on chromosomes 2 and 3 associated with earlier emergence were paradoxically at lower frequency in the apple than hawthorn host race across all four sympatric sites. However, loci on chromosome 1 did show higher frequencies of early eclosion‐associated alleles in the apple than hawthorn host race at the two southern sites, potentially accounting for their earlier eclosion phenotype. Thus, although extensive clinal genetic variation in the ancestral hawthorn race exists and contributed to the host shift to apple, further study is needed to resolve details of how this standing variation was selected to generate earlier eclosing apple fly populations in the North.  相似文献   

8.

Background and Aims

The taxonomic complexity of Crataegus (hawthorn; Rosaceae, Maleae), especially in North America, has been attributed by some to hybridization in combination with gametophytic apomixis and polyploidization, whereas others have considered the roles of hybridization and apomixis to be minimal. Study of the chemical composition and therapeutic value of hawthorn extracts requires reproducible differentiation of entities that may be difficult to distinguish by morphology alone. This study sought to address this by using the nuclear ribosomal spacer region ITS2 as a supplementary DNA barcode; however, a lack of success prompted an investigation to discover why this locus gave unsatisfactory results.

Methods

ITS2 was extensively cloned so as to document inter- and intraindividual variation in this locus, using hawthorns of western North America where the genus Crataegus is represented by only two widely divergent groups, the red-fruited section Coccineae and the black-fruited section Douglasia. Additional sequence data from selected loci on the plastid genome were obtained to enhance further the interpretation of the ITS2 results.

Key Results

In the ITS2 gene tree, ribotypes from western North American hawthorns are found in two clades. Ribotypes from diploid members of section Douglasia occur in one clade (with representatives of the east-Asian section Sanguineae). The other clade comprises those from diploid and polyploid members of section Coccineae. Both clades contribute ribotypes to polyploid Douglasia. Data from four plastid-derived intergenic spacers demonstrate the maternal parentage of these allopolyploids.

Conclusions

Repeated hybridization between species of section Douglasia and western North American members of section Coccineae involving the fertilization of unreduced female gametes explains the observed distribution of ribotypes and accounts for the phenetic intermediacy of many members of section Douglasia.  相似文献   

9.
Aquaculture industries are the fastest food producing sector and are found globally to resolve the food demands of the fast growing human population. The aquaculture sector has typically been affected by the biofilm forming aquatic pathogens that lead to economic losses with seafood spoilage. Vibrio spp. are the most common and well known aquatic pathogens causing Vibriosis infections in aquatic animals. They are natural habitants of coastal and estuarine environments where they can be associated with aquatic animals. The biofilm forming Vibrio spp. pose increasing problems with the development of antibiotic resistance that causes severe threats in aquaculture. Although commercial antibiotics have been used for Vibrio spp., several natural and organic compounds have been reported against Vibrios biofilm infections. The specific structural genes and regulatory systems of the quorum sensing system mediate the biofilm formation in Vibrios.  相似文献   

10.
Besides research on the model fungal genera Saccharomyces, Neurospora and Aspergillus, that has provided important biological knowledge in the areas of genetics, cell biology and physiology, recent investigations on non-model fungi used for food production offer insight into the mechanisms involved in food production but also adaptation and domestication processes. In this context, Penicillium roqueforti has been the most extensively studied species. This species is best known worldwide for its technological use for blue-veined cheese production and ripening. Recently, several advances related to taxonomy, population genetics, physiology and metabolism have been documented and provided deeper knowledge about this species. The methodological approaches used to study this species can be applied to other still largely understudied fungi associated with food production worldwide (e.g. P. camemberti, P. nalgiovense, P. salamii, Bisifusarium domesticum, Mucor spp.).  相似文献   

11.
B. Walther  A. Gosler 《Oecologia》2001,129(2):312-320
To maximize fitness, many animals must trade off their need to forage efficiently against their need to avoid predators. We studied such a trade-off in four species of tits (Paridae) in a forest near Oxford, UK. During winter, tits form flocks which increase feeding efficiency and reduce predation risk. These flocks feed extensively on beech (Fagus sylvatica) seeds, the abundance of which may be critical for winter survival. Because these seeds drop to the ground, where birds are exposed to sparrowhawk (Accipiter nisus) attack, tits need to trade off their need to find seeds against the proximity to protective cover, provided by dense clusters of hawthorn (Crataegus spp.). The quality of the beech crop differs markedly between trees and years. During a year of abundant beechmast, most tits searched for seeds close to protective cover. This 'safety-first' strategy precluded visits to superabundant food patches if they were too far from protective cover. Among beech trees near to cover, tits tended to prefer those with high seed density. Tits benefited from foraging under trees with high seed density because this correlated significantly with seed mass per square metre and because mean search times decreased with increasing seed density. Finally, we show experimentally that great tits, Parus major, can discriminate between edible (viable) and inedible (empty) seeds.  相似文献   

12.
Salsola is an important genus in the plant kingdom with diverse traditional, industrial, and environmental applications. Salsola species are widely distributed in temperate regions and represent about 45% of desert plants. They are a rich source of diverse phytochemical classes, such as alkaloids, cardenolides, triterpenoids, coumarins, flavonoids, isoflavonoids, and phenolic acids. Salsola spp. were traditionally used as antihypertensive, anti-inflammatory, and immunostimulants. They attracted great interest from researchers as several pharmacological activities were reported, including analgesic, antipyretic, antioxidant, cytotoxic, hepatoprotective, contraceptive, antidiabetic, neuroprotective, and antimicrobial activities. Genus Salsola is one of the most notorious plant genera from the taxonomical point of view. Our study represents a comprehensive review of the previous phytochemical and biological research on the old world Salsola secies. It is designed to be a guide for future research on different plant species that still belong to this genus or have been transferred to other genera.  相似文献   

13.
Acquired phototrophy, i.e. the use of chloroplasts from ingested prey, can be found among some species of dinoflagellates and ciliates. The best studied examples of this phenomenon in these groups are within the ciliate genus Mesodinium and the dinoflagellate genus Dinophysis, both ecologically important genera with a worldwide distribution. Mesodinium species differ considerably in their carbon metabolism. Some species rely almost exclusively on food uptake, while other species rely mostly on photosynthesis. In Mesodinium with acquired phototrophy, a number of prey organelles in addition to chloroplasts may be retained, and the host ciliate has considerable control over the acquired chloroplasts; Mesodinium rubrum is capable of dividing its acquired chloroplasts and can also photoacclimate. In Dinophysis spp., the contents of ciliate prey are sucked out, but only the chloroplasts are retained from the ingested prey. Some chloroplast house-keeping genes have been found in the nucleus of Dinophysis and some preliminary evidence suggests that Dinophysis may be capable for photoacclimation. Both genera have been claimed to take up inorganic nutrients, including NO3, indicating that processes beyond photosynthesis have been acquired. M. rubrum seems to depend upon prey species within the Teleaulax/Plagioselmis/Geminigera clade of marine cryptophytes. Up until now, Dinophysis species have only been maintained cultured on M. rubrum as food, but other ciliates may also be ingested. Dinophysis spp. and M. rubrum are obligate mixotrophs, depending upon both prey and light for sustained growth. However, while M. rubrum only needs to ingest 1–2% of its carbon demand per day to attain maximum growth, Dinophysis spp. need to obtain about half of their carbon demand from ingestion for maximum growth. Both Mesodinium and Dinophysis spp. can survive for months in the light without food. The potential role for modeling in exploring the complex balance of phototrophy and phago-heterotrophy, and its ecological implications for the mixotroph and their prey, is discussed.  相似文献   

14.
A Gleasonian model of succession (van der Valk, 1981) was used to predict the species composition of a freshwater marsh following fire. Seed bank samples from 5 vegetation types (Distichlis spicata (L.) Greene, Scirpus lacustris L., S. maritimus L., Typha spp., open water) were used in conjuction with plant life history characteristics to make predictions of post-fire species composition for each vegetation type and the entire study area. In general, predictions for specific vegetation types were not good, but were more accurate for the entire area. Stronge correlations for specific vegetation types may have been prevented by considering marsh vegetation types as discrete units, statistical sampling problems, competitive interactions, or more specific germination requirements of some species.  相似文献   

15.
Brazil has one of the highest avifauna diversities in the world, and many species are used by human populations in many different ways. Capturing wild birds for food, or to raise as pets, or for commercial purposes, together with the loss of habitat, have been the principal causes of population reductions among many species. The present work provides new information about the diversity of wild bird species used in Ceará State (Northeast Brazil) and the techniques used for capturing them, as well as the forces motivating this hunting, the commercial relationships involved, the maintenance of captive species, and the legal and conservation implications of the use of the regional avifauna. A total of 92 wild bird species belonging to 26 families were found to be used as food (39 spp.), for medicinal (3 spp.) and magic-religious (1 spp.) purposes, for commercial ends (46 spp.), or raised as pets (44 spp.), or killed to control their predation on domestic animals (5 spp.). Raising or selling birds is motivated by their singing and/or their natural beauty, with Thraupidae, Icteridae and Emberizidae being the principal families sought after for those purposes. The Family Columbidae has the greatest importance as a food source. Eleven traditional capture techniques (both active and passive) were identified. The commercial value of the birds varied depending on both intra- and inter-specific factors, and the trade in these animals involved both dealers who sold large numbers of individuals at low prices and specialists (“passarinheiros”) who sold just a few domesticated individuals of greater value. Our evaluations of transactions taking place in public markets indicated the probable over-exploitation of a number of species, and these were often imported from other states and countries. In addition to being illegal, the capture of wild birds can cause serious environmental problems that can only be addressed through public policies directed towards education, monitoring and control, alternative sources of income, wildlife management, and ecosystem conservation.  相似文献   

16.
Live corals are the key habitat forming organisms on coral reefs, contributing to both biological and physical structure. Understanding the importance of corals for reef fishes is, however, restricted to a few key families of fishes, whereas it is likely that a vast number of fish species will be adversely affected by the loss of live corals. This study used data from published literature together with independent field based surveys to quantify the range of reef fish species that use live coral habitats. A total of 320 species from 39 families use live coral habitats, accounting for approximately 8 % of all reef fishes. Many of the fishes reported to use live corals are from the families Pomacentridae (68 spp.) and Gobiidae (44 spp.) and most (66 %) are either planktivores or omnivores. 126 species of fish associate with corals as juveniles, although many of these fishes have no apparent affiliation with coral as adults, suggesting an ontogenetic shift in coral reliance. Collectively, reef fishes have been reported to use at least 93 species of coral, mainly from the genus Acropora and Porities and associate predominantly with branching growth forms. Some fish associate with a single coral species, whilst others can be found on more than 20 different species of coral indicating there is considerable variation in habitat specialisation among coral associated fish species. The large number of fishes that rely on coral highlights that habitat degradation and coral loss will have significant consequences for biodiversity and productivity of reef fish assemblages.  相似文献   

17.
Phenylpropanoids are widely distributed within the Rosaceae family. In this study, 14 phenylpropanoids, including a new phenol, 7,8-erythro-7-methoxysyringylglycerol (7), and a new sesquilignan, pinnatifidanin A I (14), were isolated and identified from the seeds of Crataegus pinnatifida. The biosynthetic relationships among the compounds 114 are proposed. The presence of these congenetic phenylpropanoids and their biosynthetic relationships may be used for identification of species of Crataegus.  相似文献   

18.
The Pacific islands have a diverse range of food and cash crops with indigenous and introduced nematode problems. The staple food crops have serious nematode pests, such as Meloidogyne spp. on sweet potato, Hirschmanniella miticausa causing corm rot of taro, and Pratylenchus coffeae and Radopholus sp. producing tuber dry rot of yams. Bananas are infested with P. coffeae or R. similis, citrus with Tylenchulus semipenetrans, rice with Aphelenchoides besseyi, and ginger with Meloidogyne spp. and R. similis. Rotylenchulus reniformis, P. zeae, P. brachyurus, and Helicotylenchus spp. are important on all of these and other crops, such as sugarcane, passion fruit, pawpaw, and cassava. Meloidogyne spp. cause serious damage to local and introduced leaf and fruit vegetables and other crops, such as tobacco, sugarcane, pawpaw, black pepper, and pyrethrum. Many other plant-parasitic genera and species, some undescribed, occur in the Pacific, and there are many islands still to be investigated.  相似文献   

19.
绿肉山楂叶中五种黄酮类成分含量动态变化   总被引:1,自引:0,他引:1  
为充分利用山楂叶用资源,采用反相高效液相色谱法,以ZORBAX Extend-C18色谱柱(250×4.6 mm,5 μm),乙腈-0.5%磷酸水溶液梯度洗脱,流速1.0 mL·min-1,检测波长345 nm,柱温25℃,对不同生长时期的绿肉山楂叶中牡荆苷、牡荆素2″-O-鼠李糖苷、金丝桃苷、芦丁和槲皮素含量进行测定。结果表明,在此分析检测条件下牡荆苷、牡荆素 2″-O-鼠李糖苷、金丝桃苷、芦丁和槲皮素的精密度、重复性、稳定性及平均加样回收率试验的RSD值均小于3%,方法准确可靠。绿肉山楂叶中含有的黄酮类成分主要以牡荆苷和金丝桃苷为主,且二者含量变化规律与其总黄酮含量变化相似,均在10月初含量达到最高;此时采摘,其质量完全符合《中国药典》的有关规定,故绿肉山楂可作为一种新的药用资源来进一步开发利用。  相似文献   

20.
Ecological speciation with gene flow may be an important mode of diversification for phytophagous insects. The recent shift of Rhagoletis pomonella from its native host downy hawthorn (Crataegus mollis) to introduced apple (Malus domestica) in the northeastern United States is a classic example of sympatric host race formation. Here, we test whether R. pomonella has similarly formed host races on four native Crataegus species in the southern United States: western mayhaw (C. opaca), blueberry hawthorn (C. brachyacantha), southern red hawthorn (C. mollis var. texana) and green hawthorn (C. viridis). These four southern hosts differ from each other in their fruiting phenology and in the volatile compounds emitted from the surface of their fruits. These two traits form the basis of ecological reproductive isolation between downy hawthorn and apple flies in the north. We report evidence from microsatellite population surveys and eclosion studies supporting the existence of genetically differentiated and partially reproductively isolated host races of southern hawthorn flies. The results provide an example of host shifting and ecological divergence involving native plants and imply that speciation with gene flow may be commonly initiated in Rhagoletis when ecological opportunity presents itself.  相似文献   

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