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1.
Raspberry cane disease, caused by a complex of fungi, is amongst the most devastating problems for raspberry production. Using resistant or highly tolerant genotypes is a promising strategy. However, until now, cultivars with good field resistance for German fruit growers as well as the primary causal pathogens of cane disease present in the eastern part of Germany, Saxony state are still unknown. The primary objective of this study was to identify the primary disease causing organisms and resistant Rubus germplasm for future breeding efforts. From 2012 to 2014, we evaluated the degree of susceptibility to cane diseases on 213 raspberry cultivars at two different locations using a rating scale. We also identified the main fungi growing on infected canes. Our results suggest that Fusarium avenaceum is the main fungus causing cane disease in Saxony. The Rubus hybrid cultivars ‘Tayberry’ (2n?=?6x?=?42), ‘Buckingham Tayberry’ (2n?=?6x?=?42) and ‘Dorman Red’ (2n?=?2x?=?14) displayed the highest levels of field resistance at both locations. Moreover, we established an in vitro assay for resistance evaluation which correlates significantly with field data and is particularly suitable for quick assessment of resistance against F. avenaceum in breeding material. Future breeding programs, aiming at cultivars with enhanced resistance towards cane diseases can use the presented data for parental selection and may employ our in vitro F. avenaceum inoculation method for parental testing and progeny selection.  相似文献   

2.
Wild crop relatives are of considerable interest in plant breeding and significant efforts have been made to transfer their genetic variation into modern crops. Of the three diploid progenitors of bread wheat (Triticum aestivum L.), only Aegilops tauschii Coss. has been explored and exploited and only for some above ground characteristics. The three wild progenitors (Aegilops speltoides Tausch., Triticum urartu Tumanian ex Gandilyan, and Aegilops tauschii) have never been assayed for root traits. Here we report such a root study, and include Triticum monococcum L. subsp. boeoticum (Boiss.) Hayek and T. turgidum L. subsp. dicoccoides (Koern. ex Asch. et Graebn.) Thell. Fifteen accessions were selected from the above wild species and tested in the presence of one bread wheat cultivar Pavon F76. Significant variation was observed between and within the taxa. Of all accessions tested, cv. Pavon F76 had the smallest root system at maturity while A. speltoides had the largest root system. Moreover, Aegilops spp. had larger mean values for root biomass when compared with Triticum spp. These results suggest there is significant unexplored potential for the use of wheat wild relatives in wheat breeding to improve the root system, or to develop synthetic mapping populations to study root traits.  相似文献   

3.
The wild species in general is considered to be the reservoir of genes especially for biotic and abiotic stresses. In okra, the predominant biotic stresses are yellow vein mosaic disease (YVMD), shoot and fruit borer and leaf hopper. Sixty eight (68) accessions belonging to four wild Abelmoschus species [Abelmoschus caillei (A. Chev.) Stevels, Abelmoschus manihot (L.) Medik., Abelmoschus moschatus (L.) Medik. and Abelmoschus tuberculatus Pal et Singh] and eight okra varieties were characterized and evaluated for phenological characters including biotic stresses under natural epiphytotic condition. The wild species examined consisted of 18 accessions (16 exotic and 2 indigenous) of A. caillei, 29 accessions of A. manihot, 16 accessions of A. moschatus and 5 accessions of A. tuberculatus. All the wild Abelmoschus species exhibited high diversity (as measured by Shannon Diversity Index) for 3 qualitative characters viz. intensity of stem colour, leaf shape, epicalyx shape, 13 quantitative characters and 3 biotic stress parameters. Among the wild species, A. caillei and A. tuberculatus showed maximum and minimum diversity for qualitative characters, respectively. There was significant variation for 19 out of 24 quantitative characters studied. Inter-species diversity pattern as estimated through Ward’s Minimum Variance Dendrogram and Principal Component Analysis revealed clear differentiation among the species with minimum overlapping indicating close association between geographical origins and clustering pattern. Intra-species diversity indicated role of specific adaptation in sub-clustering. Resistance to YVMD was found in accessions belonging to three wild species viz. A. caillei, A. manihot and A. moschatus while resistance to shoot and fruit borer and leaf hopper was found in accessions of all the four wild species. The resistant accessions can further be used for introgressing biotic stress resistance through pre-breeding into cultivated okra species.  相似文献   

4.
Three wild carrot species have been reported in the argentinian flora: Daucus montanus Humb. et Bonpl. ex Schult., D. montevidensis Link ex Sprengel and D. pusillus Michx. There is a discrepancy among authors about the distinctive morphological traits of the last two species; thus, it is difficult to ascertain if they are truly two distinct taxa. Based on the available literature and in the search of a paradigmatic site, four collection trips were carried out in 2004 and 2005 in Buenos Aires and Southern Entre Ríos provinces. Populations were sampled at 30 sites, and local environmental parameters and associated plant species were recorded. Morphological observations and chromosome counts were carried out on 10 plants/population. Three morphological phenotypes were distinguished: one in 18 populations, all with 2n = 2x = 18, and two in the remaining 12, with 2n = 2x = 22 or aneusomaty (2n = 2x = 20, 22). Populations of the first phenotype were assigned to wild D. carota and the rest, tentatively, to D. pusillus (D. montevidensis?), till further evaluations are carried out in test sites to verify this tentative conclusion.  相似文献   

5.
Potentilla alba L. is a valuable medicinal plant widely used in folk and traditional medicine and particularly promising in complex treatment of thyroid pathology. Natural resources of this species are insufficient due to ever-growing use in contemporary medicine. Comprehensive investigations of different P. alba populations are essential for the successful extension of P. alba plantings. Aiming for a better understanding of karyotype structure, chromosome behaviour in meiosis and developing new diagnostic characters, we performed molecular cytogenetic characterization and leaf structure and ultrastructure analyses of two introduced P. alba samples originating from different habitats. Based on chromosome morphology, distribution of 45S/5S rDNA and DAPI-banding patterns, all chromosomes in the karyotypes were identified and the P. alba chromosomal idiogram was constructed. Our findings confirmed P. alba karyotype stability and also revealed several diagnostic characters of this species: the features of cells of upper and lower leaf epidermis, the presence of calcium oxalate druses and three types of leaf indumentum, essential for evaluation of genetic diversity in different populations, validation of raw materials and further selection progress. The meiotic abnormalities were detected probably related to low pollen activity and indicated the advantages of vegetative propagation in the development of a P. alba plantation system.  相似文献   

6.
7.
With the development of the industrial era, environmental pollution by organic and inorganic pollutants increased and became a worldwide issue. Particularly, former industrial sites often present high concentrations of metal(loid)s. These pollutions have adverse effects not only on the environment but also to human health, as pollutants can enter the food chain. Therefore, contaminated sites need rehabilitation. Phytoremediation is a clean and low-cost solution to remediate such sites. However, vegetation establishment can be difficult on such extreme soils from both a physical and a chemical point of view. Consequently, amendments, like biochar and garden soil, must be applied. Biochar, product of biomass pyrolysis under low-oxygen conditions, showed beneficial effects on soil fertility and plant growth, as well as metal(loid) sorption properties. The aims of this study were to investigate the effects of two organic amendments, biochar and garden soil, alone or combined, on the physico-chemical properties of a post-industrial soil and the growth of two Salix species (Salix alba and Salix viminalis) and evaluate the phytostabilizing capacities of the two Salix species. In this goal, a greenhouse experiment was performed, using garden soil at 50% (v/v) and/or biochar at 2 or 5% (w/w). The results showed that biochar did not improve soil physico-chemical properties, neither did it affect plant parameters (dry weight, organ metal(loid)s concentrations). Moreover, higher metal(loid) concentrations were found in the roots compared to the upper parts. Finally, S. alba presented lower metal(loid) concentrations in the aboveground parts compared to S. viminalis, associated with a good growth, which make it a better candidate for phytostabilization of the studied soil.  相似文献   

8.
Lettuce (Lactuca sativa L.) belongs to the genus Lactuca L. and is an important vegetable worldwide. Over the past decades, there have been many controversies about the phylogeny of Lactuca species due to their complex and diverse morphological characters and insufficient molecular sampling. In this study we provide the most extensive molecular phylogenetic reconstruction of Lactuca, including African wild species, using two chloroplast genes (ndhF and trnL-F). The sampling covers nearly 40 % of the total endemic African Lactuca species and 34 % of the total Lactuca species. DNA sequences from all the subfamilies of Asteraceae in Genebank and those generated from Lactuca herbarium samples were used to establish the affiliation of Lactuca within Asteracaeae. Based on the subfamily tree, we selected 33 ndhF sequences from 30 species and 79 trnL-F sequences from 48 species to infer relationships within the genus Lactuca using randomized axelerated maximum likelihood and Bayesian inference analyses. Biogeographical, chromosomal and morphological character states were reconstructed over the Bayesian tree topology. We conclude that Lactuca contains two distinct phylogenetic clades—the crop clade and the Pterocypsela clade. Other North American, Asian and widespread species either form smaller clades or mix with the Melanoseris species. The newly sampled African endemic species probably should be treated as a new genus.  相似文献   

9.
Panax species have been used as medicinal plants in China and adjacent areas, but the difficulty in wild species identification based on morphological characters prevents the exploration and utilization of these resources. To assist in identifying the species, three plastid intergenic spacers and four nuclear genes of 129 samples from 20 different localities were sequenced to conduct the clustering analyses. P. stipuleanatus and P. notoginseng were relatively easy to be distinguished from other species based on morphological characters and clustering results. Three samples collected from Laos grouped together with those collected from Jinping (China), and they were all identified as P. vietnamensis. However, the fourth one LW4 had closer genetic relationship to P. notoginseng than to P. vietnamensis. Although they were morphologically different in petiolule length, the samples preliminarily identified as P. zingiberensis grouped together in the clustering analyses, and the results of STRUCTURE analysis suggested that samples collected from Zhenyuan shared some genetic component with P. vietnamensis. As for the samples identified as P. japonicus and P. wangianus, there were so many variations in leaves, rhizomes and rootstocks that it was difficult to differentiate them from each other. Molecular data also showed that these taxa were genetically admixed and the samples identified as P. wangianus could be classified into P. japonicus. The nucleotide diversity results indicated that the wild relatives had more substantial genetic diversity compared to P. notoginseng.  相似文献   

10.
Cucumis silentvalleyi (Manilal, T. Sabu et P.J. Mathew) Ghebretinsae et Thulin and Cucumis indicus Ghebretinsae et Thulin are two rare narrow endemics of Western Ghats of India. Both have morphological resemblance but distinguishable by a few key characters like shape of the leaf, ovary and fruit, and chromosome number. While both are edible and non-bitter, their distribution is mutually exclusive, but overlapping with Cucumis sativus var. hardwickii (Royle) Alef. (the wild and feral form of C. sativus L.). Interspecific crossability studies indicate that both are related to each other and to a lesser extent to Cucumis setosus Cogn. and Cucumis melo L. Being incompletely described, a comparative account of their morphology, phenology, distribution, ecology and conservation are provided.  相似文献   

11.
Vitellaria paradoxa C. F. Gaertn., commonly known as shea tree or Vitellaria, is ranked the most important tree species of the savannah regions in the most African countries due to its ecological and economic importance for livelihoods and national economies. However, the savannah regions are the most vulnerable areas to the global climate change. Moreover, the Vitellaria populations on farmlands are threatened by the dominance of old trees with low or lack of regeneration. In this study both morphological and genetic diversity were assessed using several phenotypic traits and 10 microsatellite markers, respectively, to assess the impact of land use and agro-ecozone types on Vitellaria in Ghana. The land use types were forests and farmlands, and the agro-ecozone types included the Transitional, Guinea, and Sudan savannah zones. The mean values of morphological traits, such as diameter at breast height (DBH) and canopy diameter (CD), were statistically different between forest (DBH = 22.20, CD = 5.37) and farmland (DBH = 39.85 CD = 7.49) populations (P < 0.00001). The Sudan savannah zone with mean petiole length of 4.96 cm showed significant difference from the other zones, likely as a result of adaptation to drier climate conditions. Genetic data analysis was based on 10 microsatellite markers and revealed high genetic diversity of Vitellaria in Ghana: mean expected heterozygosity, H e was 0.667, and allelic richness, measured as number of effective alleles A e , was 4.066. Both farmlands and forests were very diverse indicating lack of negative influence of farmer’s selection on genetic diversity. Fixation index was positive for all populations (mean F IS = 0.136) with farmlands recording relatively higher values than forests in all ecological zone types studied, probably indicating less gene flow in the farmlands. Moderate differentiation (F′ ST = 0.113) was comparable to other similar tree species. Both land use and ecological zone types influenced genetic differentiation of Vitellaria at varying levels. The species was spatially structured across three ecozones and following climatic gradient. The forest reserves are used in situ conservation for Vitellaria in Ghana. High diversity observed in the most arid zones provides opportunity to find and use appropriate plant materials for breeding climate change resilient trees.  相似文献   

12.
Low molecular weight carbohydrates of seeds of 10 species of Vicia, namely: V. angustifolia, V. articulata, V. cordata, V. ervilia, V. johannis, V. macrocarpa, V. monantha, V. narbonensis, V. pannonica and V. sativa were analyzed by the high resolution gas chromatography method. Seeds of the investigated species contain common (glucose, fructose, myo-inositol, sucrose, galactinol, di-galactosyl myo-inositol and raffinose family oligosaccharides—RFOs) and species-specific carbohydrates (d-pinitol and its α-d-galactosides—in V. articulata, V. monantha and V. pannonica or d-ononitol and its galactoside—in V. ervilia). Among the species containing in seeds RFOs as the main α-d-galactosides (V. angustifolia, V. cordata, V. johanensis, V. macrocarpa, V. narbonensis and V. sativa), an additional subgroup can be separated, which contains a set of unknown compounds (found in V. angustifolia, V. cordata and V. macrocarpa). Moreover, several other unidentified carbohydrate-containing compounds were detected exclusively in seeds of V. ervilia. The concentrations of total soluble carbohydrates (TSCs), including sugars, RFOs, cyclitols and galactosyl cyclitols and unknown compounds, in seeds differ significantly (P < 0.05) among the species. RFOs and sucrose are the main fractions in TSCs, with the exception of V. pannonica seeds, containing more galactosyl pinitols, and V. ervilia, in which unknown compounds account for 50% of TSCs. In V. ervilia RFOs occur at the lowest concentration (9.32 mg g?1 seeds), and the concentration of DGMI (di-galactosyl myo-inositol) is comparable with that of RFOs, which is unusual among all the investigated Vicia species.  相似文献   

13.
Iran is amongst the countries in the world widely known for cultivation of Prunus spp. (or stone fruits). It is both a centre of origin and diversity of the stone fruits. Numerous wild species as well as many cultivars and landraces of these fruit crops are important genetic resources today in Iran and can be used for improvement and breeding of scion and rootstock cultivars which are resistant to many biotic and abiotic stresses through modern genomics and genetic technologies. This paper discusses the distribution, ethno-botany, diversity and utilization of wild and domesticated genetic resources of stone fruits including almond (Prunus dulcis (Miller) D. A. Webb.), peach and nectarine (P. persica Batsch), European and Japanese plum (P. × domestica L., and P. salicina L., respectively), sweet and sour cherry (P. avium L., and P. cerasus L., respectively), and apricot (P. armeniaca L.), all of which are members of the Rosaceae family. The goal of this paper is to highlight the importance of Iran as a main contributor to the diversity of Prunus genetic resources in the world, as well as, present major achievements regarding identification, collection, evaluation, conservation and utilization of this valuable genetic resource in Iran.  相似文献   

14.
China is known throughout the world as one of the most diverse centres of wild Tulipa L. resources. There are 17 wild Tulipa species distributed in China, and 12 species are only distributed in Xinjiang Province. In this paper, total 83 accessions were collected from Xinjiang, Liaoning and several other provinces. Their distribution, collection, classification and evaluation were described. According to morphological characteristics, they were classified into eight species, which included T. sinkiangensis Z. M. Mao, T. altaica Pall. ex Spreng., T. iliensis Regel, T. heterophylla Baker, T. buhseana Boiss., T. thianschanica Regel, T. schrenkii Regel and T. edulis (Miq.) Baker. Their phenotypic genetic relationships were analysed and showed that the eight Tulipa species were divided into two groups: Group I included one species T. edulis, and Group II included the other seven species. Bulb renewal was observed in eight wild Tulipa species; T. iliensis and T. edulis showed that one or more long fleshy stolons formed horizontally or vertically at the basal plate of the mother bulbs, new bulblets (dropper) appeared at the top of each fleshy stolon, and the mother bulbs eventually disappeared. The analytic hierarchy process was used to evaluate the ornamental value, utilization potential and ecological adaptability of the eight identified species. The results showed that T. iliensis, T. buhseana and T. thianschanica had better ornamental value and utilization potential than any other species. The distribution, collection, classification, and evaluation of wild Tulipa species could be helpful in creating novel tulip germplasms in China.  相似文献   

15.
A number of genes that contribute to the domestication traits of cultivated rice have been identified. These include Sh4, Rc, PROG1 and LABA1, which are associated with non-shattering rachis, white pericarp, erect growth and barbless awns, respectively. The mutations giving rise to the “domestication alleles” of these genes are either invariable in cultivated rice, or have variability that is strictly associated with the phenotypic trait. This observation forms the basis to those current rice domestication models that envisage a single origin for the domesticated phenotype. Such models assume that the domestication alleles are absent or rare in wild rice, emerged under cultivation and spread across all rice groups by introgressive hybridization. We examined whole-genome sequencing datasets for wild and cultivated rice to test the former two assumptions. We found that the rc and laba1 alleles occur in wild rice with broad geographical distribution, and reach frequencies as high as 13 and 15%, respectively. These results are in agreement with previous observations of the prog1 and sh4 domestication alleles in wild populations. We also show that the diversity of the genomic regions surrounding the rc, laba1, prog1 and sh4 alleles in wild accessions is greater than that in cultivated rice, suggesting that these alleles emerged prior to domestication. Our findings indicate that the possibility that independent rice groups obtained identical domestication alleles directly from the wild population needs to be considered.  相似文献   

16.
Investigating population genetic structure and diversity, and resistance to pathogens in crop wild relatives are key steps to assess appropriate conservation and breeding programs. The Caucasian wild apple (Malus orientalis Uglitzk.) is an emblematic fruit tree of the Hyrcanian forest and is supposed to be a contributor to the cultivated apple genome (Malus domestica Borkh. Yet, no study has investigated its population structure, diversity and susceptibility to the two main pathogens of apples, the apple scab (Venturia inaqualis) and the powdery mildew (Podosphaera leucotricha). Here, we investigated population genetic structure and diversity of M. orientalis in the Hyrcanian forest as a mean to identifying future targeted populations for apple conservation and breeding programs. We genotyped using multilocus microsatellite 100 M. orientalis trees sampled in 14 sites. These trees were also screened for presence/absence of six (Rvi6, Vr, Rvi4, Rvi15, Rvi5 and Rvi11) and three (Pl-1, Pl-w, Pl-d) resistance genes to the apple scab and the powdery mildew respectively. Our results showed significant but weak between-site genetic differentiation and isolation by distance pattern suggesting substantial historical gene flow for M. orientalis in this area. We also detected a West-Eastern genetic structure across the Hyrcanian forest with five main populations showing admixture. We also showed a high diversity of resistance genes to apple scab across sites; in contrast, we only found one resistance gene to powdery mildew. These results are a first glimpse to settle wild apple conservation programs in Iran and pinpoint Iranian wild apple populations as an untapped source for apple breeding.  相似文献   

17.
There were 15 species and two variants of wild Iris recorded in Liaoning Province, where is a primary distribution area of Iris in China. According to the division of distribution area for wild plants in Liaoning, twenty-eight sites were selected for investigating wild Iris resources in Liaoning. Distribution, habitat and main accompanying plants of each Iris species were recorded. Fifty-three accessions were collected during the investigation and introduced to suitable environment. Morphological characteristics of each accession were observed. According to previous literatures and specimens, all accessions were identified and classified into 12 species and two variants. The analytic hierarchy process (AHP) was used to perform a comprehensive assessment on the ornamental value of 11 Iris species. The results showed that Iris tigridia Bunge and Iris ensata Thunb. had better ornamental value than the other species. Some suggestions for revision and classification were discussed on several Iris species.  相似文献   

18.
Saponins occur in numerous plants, including agaves, determining benefic and harmful properties to humans; their presence may favor using plants as soap and other products, but also they may cause caustic effects producing contact dermatitis. In domestication, favorable and unfavorable properties of saponins may cause an increase or decrease of their content, respectively. This study quantified and identified saponins among wild and managed populations of three agave species: A. cupreata Trel. et Berger, A. inaequidens Koch with wild and cultivated populations used for mescal production, and A. hookeri Jacobi, existing exclusively cultivated, used for production of the fermented beverage pulque. We studied 272 plants from 19 populations, quantifying contents of crude saponins through spectrometry. In 12 populations, the saponins types were identified by High Performance Liquid Chromatography–Mass-Spectrography-Time-of-Flight HPLC-MS-TOF. The highest crude saponins content was recorded in A. hookeri (26.09 mg/g), followed by A. cupreata (19.85 and 15.17 mg/g in wild and cultivated populations, respectively). For A. inaequidens, we recorded 14.21, 12.95, and 10.48 mg/g in wild, silvicultural managed and cultivated populations, respectively. We identified 18 saponins types, A. inaequidens showing all of them. A hecogenin glycoside (HG1) is found in high amounts in A. hookeri but in low quantities in A. inaequidens and A. cupreata. A. inaequidens had the greatest diversity of saponins. The contents of crude saponins in A. inaequidens and A. cupreata decrease with management intensity, but contrarily to what we expected, it was the highest in A. hookeri. We hypothesize that such high amount could be due to some saponins, probably HG1, may be precursors of sugars.  相似文献   

19.
A hybrid between Erianthus arundinaceus (Retz.) Jeswiet and Saccharum spontaneum L. which are wild related species of sugarcane (Saccharum L., Family Poaceae), was repeatedly crossed as female parent with sugarcane commercial varieties to develop near commercial sugarcane clones. The cytoplasm type of the hybrid derivatives were confirmed to be of E. arundinaceus through the mitochondrial and chloroplast DNA polymorphism of nad 4/3-4 intron segment and psbC–trnS segment, respectively. The E. arundinaceus × S. spontaneum hybrid with somatic chromosome number 2n = 62 was confirmed to have 30 chromosomes from E. arundinaceus through genomic in situ hybridization (GISH). The (E. arundinaceus × S. spontaneum) × sugarcane hybrid (2n = 118) had 24 chromosomes from E. arundinaceus whereas its next generation hybrid with sugarcane (2n = 108) had only 12 Erianthus chromosomes. The commercial sugarcane hybrid Co 15015, which is the third generation hybrid with 2n = 106 was confirmed to have two E. arundinaceus chromosomes through GISH. It is the first report of sugarcane with both alien cytoplasm and chromosome contributions from E. arundinaceus.  相似文献   

20.
Many-grained mutants occurring spontaneously among their less well-endowed field mates may have appeared to early farmers as fortunate twists of fate foreboding wealth and abundance. In domesticated barley, the number of kernel rows in spike can be tripled by recessive mutant alleles at the Six-rowed spike 1 (vrs1) locus that abolish the suppression of lateral spikelet fertility. In another barley row-type, so called intermedium-spike (int), lateral floret size is often intermediate between six-and two-rowed types. Phenotypic and sequence analyses of our intermedium-spike collection revealed that other genes can increase the size of florets and even stimulate occasional grain setting in lateral spikelets. Here, we show that a complete six-rowed phenotype occurs in a diverse panel of intermedium-spike barley carrying wildtype Vrs1 in the presence of the Int-c.a allele of the intermedium spike-c (int-c) gene, previously considered only as a modifier of lateral spikelet fertility. Int-c.a-type alleles had arisen before domestication and are associated with the enlargement of lateral florets in wild barley, suggesting that natural selection/evolution acts towards reduced lateral floret size. Since Int-c.a cannot overcome the suppression of lateral florets in the genomic background of wild barleys, we infer the existence of other gene loci, at which novel alleles or allelic combinations were selected for after domestication, to increase grain number of barley independently of Vrs1.  相似文献   

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