首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 15 毫秒
1.
Late blight (LB), caused by Phytophthora infestans, is one of the most devastating diseases of tomato (Solanum lycopersicum) worldwide. Aggressive pathogen isolates resistant to fungicides have driven research in favour of finding new sources of host resistance for tomato breeding. Recently, we reported S. pimpinellifolium accession PI 270443 exhibiting LB resistance stronger than all commercial LB-resistant tomato cultivars. The purpose of this study was to examine the inheritance of LB resistance conferred by this accession. An interspecific cross was made between PI 270443 and a LB-susceptible tomato breeding line and advanced to F10 generation. A total of 166 F9 and corresponding F10 recombinant inbred lines (RILs) were evaluated for response to LB in four replicated greenhouse experiments. Estimates of heritability (h2) of LB resistance, determined by parent–offspring (F9:F10) correlation analysis, ranged from 0.66 to 0.81, with an average of 0.76. The moderately high h2 of LB resistance in PI 270443 suggests the utility of this accession for tomato breeding. Molecular mapping and RNA-sequencing efforts are underway to identify genes underlying LB resistance in PI 270443.  相似文献   

2.
Late blight (LB), caused by Phytophthora infestans, is one of the most devastating diseases of tomato (Solanum lycopersicum) worldwide. Due to the emergence of new and aggressive P. infestans isolates, identifying new genetic resistance to LB is a priority in tomato breeding. Recently, we reported the identification of several Solanum pimpinellifolium accessions with strong LB resistance. In this study, we investigated the utility of resistant accession PI 163245 for tomato breeding by examining heritability (h2) of resistance and the response to selection for resistance. Estimates of h2 based on F2 : F3 and F3 : F4 parent : offspring correlation analyses averaged 0.79 and 0.94, respectively, suggesting the heritable nature of LB resistance in PI 163245. Analysis of response to selection for resistance from F2 to F4 generations indicated a realized h2 of 0.63, confirming the utility of this resistance in tomato breeding. Two methods of estimating the minimum number of loci involved indicated the presence of one major resistance locus. Currently, genetic mapping and breeding efforts are underway to further confirm the viability of this accession for improving tomato LB resistance.  相似文献   

3.
Late blight (LB), caused by the oomycete Phytophthora infestans, is one of the most destructive diseases of tomato and potato worldwide. Identifying and characterizing new sources of resistance is essential given the emergence of new aggressive and fungicide‐resistant P. infestans isolates. Recently, we reported identification of several new sources of LB resistance within the tomato wild species, Solanum pimpinellifolium. In this study, we examined heritability (h2) of LB resistance conferred by the S. pimpinellifolium accession PI 224710 using a parent–offspring regression (correlation) analysis. F2 and F3 progeny populations, derived from crosses between PI 224710 and a LB‐susceptible tomato breeding line, were evaluated for response to LB infection. To obtain a better estimate of h2, the F3 progeny were evaluated for LB resistance in two separate replicated experiments. The h2 estimates were similar in the two experiments and averaged ~0.87, suggesting that this resistance was highly heritable. Two different methods estimated involvement of one resistance locus. Breeding and mapping efforts are underway to further assess the viability of this newly reported LB resistance.  相似文献   

4.
Late blight (LB), caused by Phytophthora infestans, is a destructive disease of tomato (Solanum lycopersicum) worldwide. Currently, there are few commercial cultivars of tomato with resistance to LB, and the disease is mainly controlled by heavy use of fungicides. Due to the emergence of fungicide‐resistant pathogen isolates, there is a concerted effort to identify new genetic sources of resistance and breed new resistant cultivars. A recent screening identified several new tomato accessions with strong resistance to LB. Here, we report on the genetic basis of LB resistance in S. pimpinellifolium accession PI 270441, as determined by generation means analysis and analysis of response to selection, using populations derived from crosses with LB‐susceptible breeding line Fla. 8059. Heritability of LB resistance ranged from 0.76 to 0.78, and the minimum number of genes was estimated 1—few. These results suggest that transfer of LB resistance from PI 270441 to the cultivated tomato should be feasible via a traditional backcross breeding approach. Genetic mapping studies are underway to identify molecular markers associated with resistance in this accession.  相似文献   

5.
Tomatoes are the most important vegetable, globally as well as in Germany. Outdoor tomato production is seriously impaired due to increasing infections with evolving late blight (Phytophthora infestans) populations. Within organic agriculture, research is being conducted to develop regionally adapted and open pollinated cultivars of outdoor tomatoes with late blight field resistance. In the present experiment, three crosses, including wild, cocktail, and beefsteak tomatoes, were selected for field resistance against late blight in F2 at one location per cross. The comparison of positive and negative selection in F3 revealed the selection of single F2 plants to be efficient in all three crosses. F2 selection has proved to be a robust and efficient tool for breeding programs. The correlated response to selection in other traits, including yield, fruit weight, days to maturity, harvest period, and plant height, depended on the cross. It was evident that selection for desired traits combined with field resistance against late blight is promising, even in wide crosses. The most undesired attribute of wild tomatoes is the formation of shoots on leaves and in inflorescences. No correlation was observed between field resistance and shoot formation, allowing the selection of genotypes with improved field resistance and yield, but without morphological disadvantages.  相似文献   

6.
I. Simko    S. Costanzo    V. Ramanjulu    B. J. Christ    K. G. Haynes 《Plant Breeding》2006,125(4):385-389
Potato tuber blight is a disease caused by the oomycete Phytophthora infestans (Mont.) de Bary. Due to the significant economic impact of this disease, introgression of durable resistance into the cultivated potato is one of the top priorities of breeding programmes worldwide. Though numerous resistance loci against this devastating disease have already been mapped, most of the detected loci are contributing towards foliar resistance while specific information on tuber resistance is limited. To identify the genetic components of tuber resistance and its relationship to foliar resistance and plant maturity we have investigated the host‐pathogen interaction in a segregating diploid hybrid Solanum phureja × S. stenotomum family. Mature tubers from this mapping family were inoculated with a sporangial suspension of P. infestans (US‐8 clonal lineage) and evaluated for lesion expansion. No significant correlation was detected between late blight resistance in foliage and tubers, and between plant maturity and tuber resistance. Four chromosomal regions were significantly associated with tuber resistance to the disease. The largest effect was detected near the marker locus PSC (LOD 10.7) located on chromosome 10. This locus explained about 63% of the total phenotypic variation of the trait. The other three resistance‐related loci were mapped on chromosomes 8 (GP1282, LOD 4.4), 6 (CP18, LOD 4.0) and 2 (CP157, LOD 3.8). None of the four tuber resistance loci coincides with the foliage resistance loci detected in this same family. Tuber blight resistance quantitative trait loci (QTL) on chromosomes 2, 8 and 10 are distinct from the maturity QTLs and have an additive effect on tuber resistance. These results indicate that different genes are involved in foliar and tuber resistance to P. infestans in the present family and that some of the resistance genes might be associated with late maturity.  相似文献   

7.
Late blight (Phytophthora infestans) can have devastating effects on tomato production over the whole world. Most of the commercial cultivars of tomato, Solanum lycopersicum, are susceptible. Qualitative and quantitative resistance has been described in wild relatives of tomato. In general qualitative resistance can more easily be overcome by newly evolved isolates. Screening of three S. habrochaites accessions (LA1033, LA2099 and LA1777) through a whole plant assay showed that accession LA1777 had a good level of resistance to several isolates of P. infestans. To explore the potential in this wild species, an introgression line (IL) population of S. habrochaites LA1777 was used to screen individual chromosome regions of the wild species by a detached leaf assay. Two major isolates (T1,2 and T1,2,4) were used and two parameters were measured: lesion size (LS), and disease incidence (DI). Substantial variation was observed between the individual lines. QTLs were identified for LS but not for DI. The presence of five QTLs derived from LA1777 (Rlbq4a, Rlbq4b, Rlbq7, Rlbq8 and Rlbq12) results in unambiguous higher levels of resistance. All QTLs co-localized with previously described QTLs from S. habrochaites LA2099 except QTL Rlbq4b, which is therefore a novel QTL.  相似文献   

8.
The Lycopersicon hirsutum var. hirsutum accession PI 127826 is recognized as a good source of resistance to arthropod pests due to the action of the allelochemical zimgiberene, a sesquiterpene present in its glandular trichomes. Five genotypes were selected from the F2 generation of the interspecific cross Lycopersicon esculentum ‘TOM-556’ × Lycopersicon hirsutum var. hirsutum ‘PI 127826’, based on their low levels (BPX-368-clone#56) or high levels(BPX-368-clone#92, BPX-368-clone#105,BPX-368-clone#179, BPX-368-clone#250) of zingiberene. The five F2 genotypes were tested for resistance to the South American tomato pinworm Tuta absolutaalong with accession L. esculentum ‘TOM-556’ (pinworm susceptible), and the accessions L. hirsutum var. hirsutum ‘PI 127826’ and L. pennellii ‘LA716’ (resistant). The F2 clones selected for high foliar zingiberene levels showed lower scores for leaflet lesion type(LLT), percent leaflets attacked (PLA) and overall plant damage (OPD) than the low zingiberene genotypes. The results indicated that zingiberene mediates resistance to the South American pinworm, based on feeding and on ovipositing deterrence, in populations derived from the interspecific cross between Lycopersicon. esculentum and Lycopersicon hirsutum var. hirsutum. Indirect selection for high foliar zingiberene content is suggested as an efficient technique for breeding tomatoes for resistance to the South American tomato pinworm. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

9.
Late blight (LB), caused by the oomycete Phytophthora infestans, is one of the most devastating diseases of the cultivated tomato (Solanum lycopersicum) worldwide. Most commercial cultivars of tomato are susceptible to LB. Previously, three major LB resistance genes (Ph‐1, Ph‐2, Ph‐3) were identified and incorporated into a few commercial cultivars of tomato. Reduced effectiveness and potential breakdown of the resistance genes has necessitated identification, characterization and utilization of new sources of resistance. We evaluated the response of 67 accessions of the wild tomato species, S. pimpinellifolium to LB, under multiple field and greenhouse (GH) conditions and compared them with six control genotypes. Sixteen accessions were identified with strong LB resistance in both field and GH experiments. However, 12 accessions exhibited resistance similar to a control line which was homozygous for Ph‐2 + Ph‐3. Genotyping accessions with molecular markers for Ph‐2 and Ph‐3 were not conclusive, indicating that resistance in these accessions could be due to these or other resistance genes. Strong correlations were observed between field and GH disease response and between foliar and stem infection.  相似文献   

10.
Breeding for reniform nematode (Rotylenchulus reniformis) resistance is hindered by the lack of resistance in upland cotton (Gossypium hirsutum) cultivars. Resistance has been frequently identified in accessions from the Gossypium arboreum germplasm collection with accession PI 529740 rated as highly resistant. Accession PI 529740 was crossed with the susceptible G. arboreum accession PI 529729 to develop an F2 population for genetic characterization. The population showed quantitative variation suggesting multiple genes conferred the resistant phenotype. Thirteen of the 216 F2 plants showed resistance similar to the resistant parent and these data supported a two recessive gene model. Sixty plants were classified as resistant or moderately resistant, indicating a single recessive gene conferred the moderately resistant phenotype. The classification of 24 F2:3 families for nematode resistance generally supported the classification of the corresponding F2 plants; however, most families were highly variable for infection with no families rated as resistant. This information will aid in the introgression of resistance into upland cotton as larger populations will be required to successfully recover resistance conferred by multiple recessive genes.  相似文献   

11.
Late blight caused by Phytophthora infestans is one of the most destructive diseases of tomato (Solanum lycopersicum L.) that mainly occurs in cool and wet environments. With the spread of the A2 mating type and new clonal lineages, fewer fungicides provide effective control of the disease, which has increased its worldwide threat. Host resistance could contribute significantly to sustainable disease control. Ph‐3 is a race‐specific late blight resistance gene commonly used in commercial tomato breeding. Availability of precise and easy to use gene‐based markers would facilitate selection. In this study, a Ph‐3 on‐gene cleaved amplified polymorphic sequence (CAPS) marker, Ph3.gsm/HincII, was developed based on the published gene sequence of Ph‐3. The effectiveness of the marker was evaluated along with other published Ph‐3 markers using an F9 recombinant inbred line (RIL) population derived from NC 23E‐2(93) × L3708. Markers Ph3.gsm/HincII and TG328/BstNI accurately genotyped the RIL population for Ph‐3. In addition, Ph3.gsm/HincII was able to differentiate variable susceptible alleles. This reliable codominant DNA marker would be very useful in marker‐assisted selection, particularly for resistance gene pyramiding.  相似文献   

12.
Potato leafroll virus (PLRV; Genus Polerovirus; Family Luteoviridae) is one of the most important virus pathogens of potato worldwide and breeders are looking for new sources of resistance. Solanum etuberosum Lindl., a wild potato species native to Chile, was identified as having resistances to PLRV, potato virus Y, potato virus X, and green peach aphid. Barriers to sexual hybridization between S. etuberosum and cultivated potato were overcome through somatic hybridization. Resistance to PLRV has been identified in the BC1, BC2 and BC3 progeny of the somatic hybrids of S. etuberosum (+) S. tuberosum haploid × S. berthaultii Hawkes. In this study, RFLP markers previously mapped in potato, tomato or populations derived from S. palustre (syn S. brevidens) × S. etuberosum and simple sequence repeat (SSR) markers developed from tomato and potato EST sequences were used to characterize S. etuberosum genomic regions associated with resistance to PLRV. The RFLP marker TG443 from tomato linkage group 4 was found to segregate with PLRV resistance. This chromosome region has not previously been associated with PLRV resistance and therefore suggests a unique source of resistance. Synteny groups of molecular markers were constructed using information from published genetic linkage maps of potato, tomato and S. palustre (syn. S. brevidens) × S. etuberosum. Analysis of synteny group transmission over generations confirmed the sequential loss of S. etuberosum chromosomes with each backcross to potato. Marker analyses provided evidence of recombination between the potato and S. etuberosum genomes and/or fragmentation of the S. etuberosum chromosomes.  相似文献   

13.
  相似文献   

14.
Asian rust, caused by the fungus Phakopsora pachyrhizi, is the most severe disease currently threatening soybean crops in Brazil. The development of resistant cultivars is a top priority. Genetic characterization of resistance genes is important for estimating the improvement when these genes are introduced into soybean plants and for planning breeding strategies against this disease. Here, we infected an F2 population of 140 plants derived from a cross between ‘An-76’, a line carrying two resistance genes (Rpp2 and Rpp4), and ‘Kinoshita’, a cultivar carrying Rpp5, with a Brazilian rust population. We scored six characters of rust resistance (lesion color [LC], frequency of lesions having uredinia [%LU], number of uredinia per lesion [NoU], frequency of open uredinia [%OU], sporulation level [SL], and incubation period [IP]) to identify the genetic contributions of the three genes to these characters. Furthermore, we selected genotypes carrying these three loci in homozygosis by marker-assisted selection and evaluated their genetic effect in comparison with their ancestors, An-76, PI230970, PI459025, Kinoshita and BRS184. All three genes contributed to the phenotypes of these characters in F2 population and when pyramided, they significantly contributed to increase the resistance in comparison to their ancestors. Rpp2, previously reported as being defeated by the same rust population, showed a large contribution to resistance, and its resistance allele seemed to be recessive. Rpp5 had the largest contribution among the three genes, especially to SL and NoU. Only Rpp5 showed a significant contribution to LC. No QTLs for IP were detected in the regions of the three genes. We consider that these genes could contribute differently to resistance to soybean rust, and that genetic background plays an important role in Rpp2 activity. All three loci together worked additively to increase resistance when they were pyramided in a single genotype indicating that the pyramiding strategy is one good breeding strategy to increase soybean rust resistance.  相似文献   

15.
Greenbug is a major damaging insect to sorghum production in the United States. Among various virulent greenbug biotypes, biotype I is the most predominant and severe for sorghum. To combat with the damaging pest, greenbug resistant sources were obtained from screening sorghum germplasm collection. This experiment was conducted to identify the genomic regions contributing resistance to greenbug biotype I in a sorghum accession, PI 607900. An F2 mapping population consisting of 371 individuals developed from a cross of the resistant line with an elite cultivar, BTx623 (susceptible) were tested and scored for their response to greenbug feeding in the greenhouse. Significant differences in resistance were observed between the two parental lines and among their F2 progeny in response to greenbug feeding at 7, 10, 14 and 21 days after infestation. A linkage map spanning a total length of 729.5 cM across the genome was constructed with 102 polymorphic SSR markers (69 genomic and 33 EST SSRs). Of those microsatellite markers, 48 were newly developed during this study, which are a useful addition for sorghum genotyping and genome mapping. Single marker analysis revealed 29 markers to be significantly associated with the plant response to greenbug feeding damage. The results from interval mapping, composite interval mapping and multiple interval mapping analyses identified four major QTLs for greenbug resistance on chromosome 9. These QTLs collectively accounted for 34–82 % of the phenotypic variance in greenbug resistance. Minor QTLs located on chromosome 3 explained 1 % of the phenotypic variance in greenbug resistance. The major allele for greenbug resistance was on chromosome 9 close to receptor-like kinase Xa21-binding protein 3. These markers are useful to screen more resistant genotypes. Furthermore, the markers tagged to QTL regions can be used to enhance the sorghum breeding program for greenbug resistance through marker-assisted selection and map-based cloning.  相似文献   

16.
Crown rust resistance is an important selection criterion in ryegrass breeding. The fungal disease caused by P. coronata causes yield loss and a reduced quality of the fodder crop. Molecular markers were used to unravel the genomic organization of crown rust resistance in a segregating L. perenne population. Two genomic regions involved in crown rust resistance were identified that together explained 35% of the phenotypic variance present. Bulked segregant analysis in combination with AFLP markers was a suitable method to identify DNA markers associated with genomic regions of major effect. One cluster of AFLP markers explained 6.1% of the variance and mapped to linkage group 2, a genomic region known to contain crown rust resistance genes. A second cluster of AFLP markers detected a novel genomic region of major effect that explained 27.7% of the phenotypic variance in crown rust resistance. This cluster was unlinked to the cluster on linkage group 2. Divergent selections performed within the segregating F1 population on the basis of genotype and phenotype revealed that the markers associated with crown rust resistance identified in this study have potential for marker assisted selection. Selection of plants on the basis of markers was more straightforward than the selection on the basis of phenotype.  相似文献   

17.
Tomato (Solanum lycopersicum) production in tropical and subtropical regions of the world is limited by the endemic presence of Tomato yellow leaf curl virus (TYLCV). Breeding programmes aimed at producing TYLCV‐resistant tomato cultivars have utilized resistance sources derived from wild tomato species. So far, all reported breeding programmes have introgressed TYLCV resistance from a single wild tomato source. Here, we tested the hypothesis that pyramiding resistances from different wild tomato species might improve the degree of resistance of the domesticated tomato to TYLCV. We have crossed TYLCV‐resistant lines that originated from different wild tomato progenitors, Solanum chilense, Solanum peruvianum, Solanum pimpinellifolium, and Solanum habrochaites. The various parental resistant lines and the F1 hybrids were inoculated in the greenhouse using viruliferous whiteflies. Control, non‐inoculated plants of the same lines and hybrids were exposed to non‐viruliferous whiteflies. Following inoculation, the plants were scored for disease symptom severity, and transplanted to the field. Resistance was assayed by comparing yield of inoculated plants to those of the control non‐inoculated plants of the same variety. Results showed that the F1 hybrids between the resistant lines and the susceptible line suffered major yield reduction because of infection, but all hybrids were more resistant than the susceptible parent. All F1 hybrids resulting from a cross between two resistant parents, showed a relatively high level of resistance, which in most cases was similar to that displayed by the more resistant parent. In some cases, the hybrids displayed better levels of resistance than both parents, but the differences were not statistically significant. The F1 hybrid between a line with resistance from S. habrochaites and a line with resistance from S. peruvianum (HAB and 72‐PER), exhibited the lowest yield loss and the mildest level of symptoms. Although the resistance level of this F1 hybrid was not statistically different from the level of resistance displayed by the 72‐PER parent itself, it was statistically better than the level of resistance displayed by the F1 hybrids between 72‐PER and any other resistant or susceptible line.  相似文献   

18.
Genetic analysis of resistance of plant introduction (PI) 438489B to soybean cyst nematode (SCN) have shown that this PI is highly resistant to many SCN HG types. However, validation of the previously detected quantitative trait loci (QTL) has not been done. In this study, 250 F2:3 progeny of a Magellan (susceptible) × PI 438489B (resistant) cross were used for primary genetic mapping to detect putative QTL for resistance to five SCN HG types. QTL confirmation study was subsequently conducted using F6:7 recombinant inbred lines (RILs) derived from the same cross. Simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers were employed for molecular genotyping. Interval mapping (IM), permutation tests, cofactor selection, and composite interval mapping (CIM) were performed to identify and map QTL. Results showed that five QTL intervals were associated with resistance to either multiple- or single-HG types of SCN. Among these, two major QTL for resistance to multiple-SCN HG types were mapped to chromosomes (Chr.) 8 and 18, consistent with the known rhg1 and Rhg4 locations. The other QTL were mapped to Chr. 4. The results of our study confirmed earlier reported SCN resistance QTL in this PI. Moreover, SSR and SNP molecular markers tightly linked to these QTL can be useful for the near-isogenic lines (NILs) development aiming to fine-mapping of these QTL regions and map-based cloning of SCN resistance candidate genes.  相似文献   

19.
Sixteen‐hundred BC1 plants of a cross between an early blight (EB) susceptible tomato (Lycopersicon esculentum Mill.) breeding line (‘NC84173’ maternal and recurrent parent) and a resistant accession (‘PI126445’) of the tomato wild species Lycopersicon hirsutum Humb. and Bonpl. were grown in a field in 1998. This population was segregating (among other traits) for growth habit, self‐incompatibility and earliness in maturity. To eliminate confounding effects of these factors on disease evaluation and h2 estimation, plants that were self‐incompatible, indeterminate and/or late‐maturing were eliminated. The remaining plants (146), which were self‐compatible and determinate (sp./sp.) in growth habit, with early‐ to mid‐season maturity, were evaluated for EB resistance and self‐pollinated to produce BC1S1 seed. The 146 BC1S1 progeny families, consisting of 30 plants per family, were grown in a replicated field trial in 1999 and evaluated for EB resistance and plant maturity. For each of the 146 BC1 plants and corresponding BC1 families, the area under the disease progress curve (AUDPC) and final disease severity (final percentage defoliation) were determined and used to measure disease resistance. The distributions of the AUDPC and final percentage defoliation values in the BC1 and BC1S1 generations indicated that resistance from ‘PI126445’ was quantitative in nature. Estimates of h2 for EB resistance, computed by correlation between BC1S1 progeny family means and BC1 individual plant values, ranged from 0.69 to 0.70, indicating that EB resistance of ‘P1126445’ was heritable. Across BC1S1 families, a small, but significant, negative correlation (r = ‐0.26, P < 0.01) was observed between disease resistance and earliness in maturity. However, several BC1S1 families were identified with considerable EB resistance and reasonably early maturity. These families should be useful for the development of commercially acceptable EB‐resistant tomato lines.  相似文献   

20.
This study estimated the heritability (h 2) of early blight (EB) resistance in filial progeny of a cross between a susceptible (`NC84173';mid-season maturity) and a resistant (`NC39E'; late-season maturity)tomato breeding lines. It addition, it examined the potential of identifying progeny with mid-season maturity and EB resistance. A total of 162F2 plants were grown under field conditions in 1998 and evaluated for disease symptoms three times during the season, and the area under the disease progress curve (AUDPC) and final percent defoliation (disease severity) were determined. The F2 plants were self-pollinated and F3 seeds produced. The 162 F3 progeny families, consisting of 20 plants per family, were grown in a replicated field trial in 1999 and evaluated for EB resistance (final percent defoliation) and plant maturity(days to 50% ripe fruit). The distributions of the final percent defoliation values in the F2 and F3 generations indicated that resistance from `NC39E' was quantitative in nature. Estimates of h 2 for EB resistance, computed as the correlation coefficients between F3progeny family means and F2 individual plant values, ranged from0.65 to 0.71, indicating that EB resistance of `NC39E' was heritable. Across F3 families, a negative correlation (r = –0.46, p< 0.01) was observed between disease severity and earliness in maturity, indicating that plant maturity affected disease severity. However, several F3 families were identified with considerable EB resistance and mid-season maturity, indicating that resistance from `NC39E' might be useful for the development of commercially acceptable EB resistant tomato cultivars. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号