Powdery mildew,caused by Blumeria graminis f.sp.tritici(Bgt),is a devastating disease that seriously threatens wheat yield and quality.To control this disease,host resistance is the most effective measure.Compared wit...Powdery mildew,caused by Blumeria graminis f.sp.tritici(Bgt),is a devastating disease that seriously threatens wheat yield and quality.To control this disease,host resistance is the most effective measure.Compared with the resistance genes from common wheat,alien resistance genes can better withstand infection of this highly variable pathogen.Development of elite alien germplasm resources with powdery mildew resistance and other key breeding traits is an attractive strategy in wheat breeding.In this study,three wheat-rye germplasm lines YT4-1,YT4-2,and YT4-3 were developed through hybridization between octoploid triticale and common wheat,out of which the lines YT4-1 and YT4-2 conferred adult-plant resistance(APR)to powdery mildew while the line YT4-3 was susceptible to powdery mildew during all of its growth stages.Using genomic in situ hybridization,multi-color fluorescence in situ hybridization,multi-color GISH,and molecular marker analysis,YT4-1,YT4-2,and YT4-3 were shown to be cytogenetically stable wheat-rye 6R addition and T1RS.1BL translocation line,6RL ditelosomic addition and T1RS.1BL translocation line,and T1RS.1BL translocation line,respectively.Compared with previously reported wheat-rye derivative lines carrying chromosome 6R,YT4-1 and YT4-2 showed stable APR without undesirable pleiotropic effects on agronomic traits.Therefore,these novel wheat-rye 6R derivative lines are expected to be promising bridge resources in wheat disease breeding.展开更多
In a wheat breeding line XQ-0508 showing consistent resistance to powdery mildew disease,a recessive gene,designated PmXQ-0508,was identified and mapped to a distal region on chromosome arm 2BS.Of three resistance-ass...In a wheat breeding line XQ-0508 showing consistent resistance to powdery mildew disease,a recessive gene,designated PmXQ-0508,was identified and mapped to a distal region on chromosome arm 2BS.Of three resistance-associated genes in this region,one encoding a protein kinase was selected as the primary candidate for PmXQ-0508.Ten closely linked DNA markers developed in the study could be used for marker-assisted selection for powdery-mildew resistance in breeding programs.展开更多
Rye(Secale cereale)is a valuable gene donor for wheat improvement,especially for its resistance to diseases.Developing rye-derived resistance sources is important for wheat breeding.In the present study,two wheat-rye ...Rye(Secale cereale)is a valuable gene donor for wheat improvement,especially for its resistance to diseases.Developing rye-derived resistance sources is important for wheat breeding.In the present study,two wheat-rye derivatives,designated JS016 and JS110,were produced by crossing common wheat cultivar Yangmai 23 with Pakistani rye accession W2A.Using sequential genomic in situ hybridization(GISH)and multicolor fluorescence in situ hybridization(mc-FISH),JS016 and JS110 were identified as a T6BS.6RL translocation line and a T6BS.6BL6RL translocation line,respectively.Ten newly 6RL chromosome arm-specific markers were developed and used to confirm the 6RL translocation.The wheat 55K single-nucleotide polymorphism(SNP)array further verified the molecular cytogenetic identification results above and clarified their breakpoints at 430.9 and 523.0 Mb of chromosome 6B in JS016 and JS110,respectively.Resistance spectrum and allelism test demonstrated that JS016 and JS110 possessed novel powdery mildew resistance gene(s)that was derived from the 6RL translocation but differed from Pm20.Moreover,JS016 and JS110 had better agronomic traits than the previously reported 6RL translocation line carrying Pm20.To efficiently transfer and detect the 6RL translocation from JS016 and JS110,one 6RL-specific Kompetitive allele specific PCR(KASP)marker was developed and validated in high throughput marker-assisted selection(MAS).展开更多
Common wheat (Triticum aestivum L.) is one of the most important food crops. Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is one of the most serious diseases on wheat. In this study, the changes o...Common wheat (Triticum aestivum L.) is one of the most important food crops. Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is one of the most serious diseases on wheat. In this study, the changes of endogenous bacteria in root, stem and leaf tissues of wheat infected and uninfected with powdery mildew were measured based on 16S rDNA. Integration, OTU cluster analysis, taxonomic analysis, diversity index, Shannon-Index curve, Rank-Abundance curve and PCoA analysis were carried out for each sample, and the roots, stems and leaves of different tissue parts were classified and summarized. The results showed that the infection of wheat powdery mildew had a certain effect on endophytic bacteria in stem tissue. There are also differences in the control and treatment of leaf tissue and root tissue. This indicated that endophytic bacteria were distributed differently in different parts of wheat.展开更多
Powdery mildew caused by Blumeria graminis f.sp.tritici(Bgt)is a destructive wheat disease.Although it can be easily overcome by deployment of resistance genes,the resistance is often quickly compromised by pathogen v...Powdery mildew caused by Blumeria graminis f.sp.tritici(Bgt)is a destructive wheat disease.Although it can be easily overcome by deployment of resistance genes,the resistance is often quickly compromised by pathogen virulence.Thus,exploration and characterization of new resistance genes is always ongoing.Line NJ3946 derived from a cross of einkorn wheat accessions TA2032 and M389 showed resistance to powdery mildew.Inheritance analysis of an F2 population derived from a cross of NJ3946 and M389 suggested that the resistance was conferred by a dominant allele.With polymorphic markers identified through bulked segregant analysis(BSA),this gene was mapped to a novel locus on chromosome 3A,and was designated as PmNJ3946.Bulked segregant RNA-seq analysis(BSR-seq)was conducted to obtain more closely linked markers,which allowed delimitation of the PMNJ3946 locus to a 0.9 cM interval covering a physical distance of less than 1 Mb.PMNJ3946 was flanked by Xwgrc5153 and SNP-derived marker CHS21_3A008915069,and co-segregated with SNP-derived markers CHS21_3A008939814 and CHS21_3A008943175.The PmNJ3946 discovery expands the diversity of powdery mildew resistance genes and is useful for wheat breeding.展开更多
Chinese peony(Paeonia lactiflora Pall.)is both medicinally and aesthetically beneficial.Powdery mildew is a common fungal disease that seriously jeopardizes the value of numerous species,including peonies as a crop.In...Chinese peony(Paeonia lactiflora Pall.)is both medicinally and aesthetically beneficial.Powdery mildew is a common fungal disease that seriously jeopardizes the value of numerous species,including peonies as a crop.In order to provide a basis for the prevention and treatment of peony powdery mildew,we examined the microbial diversity,the malondialdehyde(MDA)concentrations and antioxidant enzyme activities of peony leaves infected with three levels of powdery mildew to determine any modifications to the leaf's antioxidant enzyme systems and microbial community structure following the onset of disease.The results show that the MDA content rose as the degree of infection became worse.Antioxidant enzyme activity rose and then declined.Following the initiation of powdery mildew,fungal community diversity decreased,whereas there was not any appreciable change in bacterial communities according to microbial diversity sequencing.The relative abundance of more than half of fungal species decreased,with the bacterial genera displaying both abundant and diminished communities with less pronounced alterations in their community structure after the disease spread.Significant different taxa that were critical to the organization of each microbiome were found.Correlation analysis showed that the relative abundance of powdery mildew pathogenic fungal genus Erysiphe was correlated with those of 11 fungal genera and one bacterial genus.Among them,Aureobasidium,Neosetophoma and Sclerostagonospora showed significant positive correlations with Erysiphe and MDA.展开更多
Sunflower is one of the most used commercial oilseed crops and suffers due to Powdery mildew. RNA sequence alteration occurs due to RNA editing which is a post transcriptional modification. It causes a deviation from ...Sunflower is one of the most used commercial oilseed crops and suffers due to Powdery mildew. RNA sequence alteration occurs due to RNA editing which is a post transcriptional modification. It causes a deviation from the genomic DNA sequence resulting in RNA-DNA differences. Accurate study of RNA editing events in diverse species is possible by NGS based methods. Here, we performed RNA sequencing of 12 leaf transcriptomes, which include three genotypes of Helianthus annuus (2023B, TX16R and ID25), H. debilis, H. niveus, and H. praecox along with their respective powdery mildew pathogen infected variants and systematically analysed the mitochondrial RNA editing events using computational reference-based mapping approach. We discovered 687 editing sites, 220 editing events in the protein-coding regions, among all species and genotypes considered in this study. These included “C to U” and “U to C” RNA editing events. On further analysis, we observed that these editing events include 14 different types of amino acid changes that involve the creation of two stop codon events. The conserved editing sites identified were 247 accounting for ~36% of all the editing sites identified. This study provides a detailed picture of the Helianthus species’ mitochondrial RNA editing status. We have identified and characterized for the first time, genotype-specific, species-specific, and stress-specific RNA editing events which may be useful as a potential source for stress-responsive studies in the future.展开更多
Various strains of powdery mildew(PM),a notorious plant fungal disease,are prevalent and pose a significant threat to plant health.To control PM,transgenic technology can be used to cultivate more resistant plant vari...Various strains of powdery mildew(PM),a notorious plant fungal disease,are prevalent and pose a significant threat to plant health.To control PM,transgenic technology can be used to cultivate more resistant plant varieties.In the present study,we utilized the rapid amplification of cDNA ends(RACE)technique to clone the full-length cDNA sequence of the EuCHIT30.7 gene to explore plant genes with disease resistance functions.Bioinformatics analysis revealed that this gene belongs to the GH18 family and is classified as a class III chitinase.The EuCHIT30.7 gene is expressed throughout the Eucommia ulmoides plant,with the most abundant expression in male flowers.Subcellular localization analysis indicated that the protein encoded by this gene was detected within both the cell membrane and cytoplasm.Upon PM inoculation,overexpression of EuCHIT30.7 in tobacco plants led to a significantly reduced relative lesion area and a decreased spore count compared to both wild-type and empty vector control plants.Activities of the protective enzymes,namely,peroxidase(POD),superoxide dismutase(SOD),catalase(CAT),and phenylalaninammo-nialyase(PAL),in tobacco plants overexpressing EuCHIT30.7 were significantly greater than those in wild-type and empty vector tobacco plants.Furthermore,the rate of increase in malondialdehyde(MDA)content was significantly lower in tobacco plants expressing EuCHIT30.7 compared to control tobacco plants.In EuCHIT30.7 transgenic tobacco,the expression of pathogen-related protein genes,namely,PR2,PR5,PR1a,PDF1.2,and MLP423,along with the tobacco PM negative regulatory gene,MLO2,were significantly higher compared to control tobacco plants.These findings suggested that EuCHIT30.7 significantly enhances the resistance of tobacco to PM.展开更多
Cucumber is an important vegetable worldwide,and powdery mildew(PM)is a common and serious disease of cucumbers.Breeding disease-resistant cucumber varieties is the most advantageous strategy to control this disease.I...Cucumber is an important vegetable worldwide,and powdery mildew(PM)is a common and serious disease of cucumbers.Breeding disease-resistant cucumber varieties is the most advantageous strategy to control this disease.In recent years,exploration and identification of cucumber PM resistance genes have achieved great advancement,and many genes have been cloned and verified using different methods.However,the resistance mechanism of cucumber PM is still unclear,and many ambiguities need to be elucidated urgently.In this review,we summarized the research advances in PM resistance in cucumbers,including genetic analysis,quantitative trait locus mapping,map-based cloning,transcriptomics,mlo-mediated PM resistance,and mining of noncoding RNAs involved in resistance.Finally,the research directions and the problems that need to be solved in the future were discussed.展开更多
[Objective] This study was carried out to determine the induction effect of jasmonic acid（JA）on powdery mildew resistance in wheat,the activation effect on the expressions of plant disease resistance related genes,a...[Objective] This study was carried out to determine the induction effect of jasmonic acid（JA）on powdery mildew resistance in wheat,the activation effect on the expressions of plant disease resistance related genes,and to investigate the relationship between the induced resistance and the gene expression patterns.[Method] Three powdery mildew susceptible cultivars of ＂Chinese Spring＂,＂Pumai 9＂ and ＂Zhoumai 18＂ typically representing different phenotypes in the field were employed.The powdery mildew was assessed by detached leaf assay,and real time quantitative RT-PCR was used to determine the expression patterns of 9 disease resistance related genes of PR1（PR1.1）,PR2（β,1-3 glucanase）,PR3（chitinase）,PR4（wheatwin1）,PR5（thaumatin-like protein）,PR9（TaPERO,peroxidase）,PR10,TaGLP2a（germin-like）and Ta-JA2（jasmonate-induced protein）in leaf of the three cultivars.[Result] MeJA application enhanced the powdery mildew resistances of ＂Chinese Spring＂,＂Pumai 9＂ and ＂Zhoumai 18＂.The induced powdery mildew resistance could be detected from 12 h to 96 h after MeJA treatment,and the peak value was at 24 h.Though there were differences between the three cultivars,MeJA significantly effect on the expressions of the 8 disease resistance related genes except TaGLP2a,and the peak values were at 12 h,24 h or 48 h after treatments.The strongest activation of MeJA was on PR9 and PR1 that their expressions could reach more than 100 times of the untreated samples.MeJA strongly activated PR2、PR4、PR5、PR3、PR10 and Ta-JA2,their expression could reach 10 to 70 times,and there was almost no activation effect on TaGLP2a.The induced powdery mildew resistance positively correlated with the induced expressions of the 8 disease related genes.[Conclusion] The induced powdery mildew resistance positively correlated with the induced expressions of the disease related genes.Jasmonate signalling plays a role in defence against Blumeria graminis f.sp.tritici.and future manipulation of this pathway may improve powdery mildew resistance in wheat.展开更多
[Objective] This study aimed to screen effective fungicide for prevention and control of apple powdery mildew. [Method] Field efficacy of six kinds of fungi- cides with 18 concentrations against apple powdery mildew w...[Objective] This study aimed to screen effective fungicide for prevention and control of apple powdery mildew. [Method] Field efficacy of six kinds of fungi- cides with 18 concentrations against apple powdery mildew was investigated. [Re- sult] 4 000-fold triflumizole WP exhibited the highest control efficacy of 82.96%, fol- lowed by 3 000-fold triflumizole WP with control efficacy of 77.75%, while 800-fold and 1 000-fold 70% thiophanate methyl WP exhibited relatively low control efficacy, which was both lower than 60%. [Conclusion] In actual production, 4 000-fold triflu- mizole WP and 3 000-fold triflumizole WP should be used alternately to control and prevent apple powdery mildew.展开更多
[ Objective ] The paper was to explore the pathogenic mechanism of tomato powdery mildew, and to study the effects of the disease on photosynthetic characteristics of tomato. [ Method ] With four tomato varieties as m...[ Objective ] The paper was to explore the pathogenic mechanism of tomato powdery mildew, and to study the effects of the disease on photosynthetic characteristics of tomato. [ Method ] With four tomato varieties as materials, the pathogen of tomato powdery mildew was artificially inoculated. After the varieties were infected, the parameters including net photosynthetic rate, stomatal conductance and transpiration rate of tomato leaf were measured by Li-6400 portable photo- synthesis detector under natural lighting conditions. [ Result] The net photosynthetic rate, stomatal conductance and transpiration rate of four tomato varieties all decreased after infection. However, the decrease extent of these parameters of four varieties was different. The parameters of seriously damaged Jinyangdajuxdng （ No. 4） and Xinsheng No. 1 （ No. 5 ） decreased greatly, while the parameters of slightly damaged Lujia （ No. 13 ） and improved 98-6 decreased lightly. [ Condu- sion] The results could provide theoretical basis for the study on pathogenic mechanism, new prevention way and resistance breeding of tomato powdery mildew.展开更多
Yunmai52, developed by crossing with common wheat-Haynaldia villosa6AL/6VS translocation line 92R149 as a resistant parent in 1992, was a common wheat cultivar approved and released in 2007 in Yunnan Province, China, ...Yunmai52, developed by crossing with common wheat-Haynaldia villosa6AL/6VS translocation line 92R149 as a resistant parent in 1992, was a common wheat cultivar approved and released in 2007 in Yunnan Province, China, which is characterized by high resistance to powdery mildew and stripe rust. In this study,an F_2 population derived from a cross K78S/Yunmai52 was constructed to investigate the resistance genes, where K78 S is a wheat male sterile line susceptible to powdery mildew and stripe rust. Phenotypic identification of the parents, F_1 and F_2 populations and chi-square analyses showed that F_1 population was immune to stripe rust and powdery mildew; the segregation ratio of resistance and susceptibility to powdery mildew（χ~2=1.10χ~2_（1,0.05）=3.84） and stripe rust（χ~2=0.15χ~2_（1,0.05）=3.84） fit to a 3：1 ratio in F_2 population, indicating that Yunmai52 harbors a dominant stripe rust resistance gene and a dominant powdery mildew resistance gene. The individuals were further detected with a marker co-segregated with Pm21（SCAR_（1400）） and two markers closely linked with Yr26（XWe173 and Xbarc181）. The results showed that polymorphic bands could be amplified between the parents and between resistance and susceptibility gene pools at the same locus. Randomly 96 individuals of F_2 population were selected for verification. The results showed that the phenotype was significantly correlated with the genotype. The detection accuracy of markers SCAR_（1400）, XWe173 and Xbarc181 was 100%, 97.91% and 92.70%, respectively.Yunmai52 harbored powdery mildew resistance gene Pm21 and stripe rust resistance gene Yr26, which were both derived from 6AL/6VS translocation line 92R149.In addition, the results also demonstrate that Pm21 and Yr26 are two genes conferring durable resistance to powdery mildew and stripe rust in wheat.展开更多
ln order to explore the design and construction of cucumber powdery mildew warning system in solar greenhouse, internet of things technology was used to conduct the real-time dynamic monitoring of the incidence of cuc...ln order to explore the design and construction of cucumber powdery mildew warning system in solar greenhouse, internet of things technology was used to conduct the real-time dynamic monitoring of the incidence of cucumber powdery mildew and cucumber growth environment in solar greenhouse. The growth environ-ment included temperature and humidity of air and soil. Logistic regression model was used to construct cucumber powdery mildew warning model. The results showed that humidity characteristic variable （maximum air humidity） and temperature characteristic variable （maximum air temperature） had significant effects on the inci-dence probability of cucumber powdery mildew in solar greenhouse. And it was fea-sible to construct cucumber powdery mildew warning system in solar greenhouse with internet of things.展开更多
[Objective] The study discussed the indoor activity and field control effect of vegetable oil on cucumber powdery mildew.[Method] The cucumber seedlings of Changchunmici were adopted as the material,which were inocula...[Objective] The study discussed the indoor activity and field control effect of vegetable oil on cucumber powdery mildew.[Method] The cucumber seedlings of Changchunmici were adopted as the material,which were inoculated with the fungus pathogen of cucumber powdery mildew naturally occurred in the field.The indoor protective test and field test were performed respectively to observe the control effects of different plant oils EC on the cucumber powdery mildew.[Result] When six plant oils EC including cottonseed oil,soybean oil,canola oil,corn oil,sesame oil and sunflower oil was diluted into 10 and 5 ml/L,they had better control effect on cucumber powdery mildew.As for the indoor protective effect,the protective effect of the vegetable oil EC was equivalent to the control agent triadimefon EC,the field control effect of vegetable oil EC was in the range of 60%-75%,which was consistent with 69%-70% control effect of contrast agent with 1 ml/L triadimefon EC dilution.[Conclusion] All vegetable oils EC had significant control effect on cucumber powdery mildew in the test.展开更多
The Pm18 gene of wheat confers resistance to the powdery mildew which is one of the mostserious diseases in many regions of the world. In this study, bulked segregant analysis(BSA) was used to develop randomly amplifi...The Pm18 gene of wheat confers resistance to the powdery mildew which is one of the mostserious diseases in many regions of the world. In this study, bulked segregant analysis(BSA) was used to develop randomly amplified polymorphic DNA (RAPD) markers linked toPm18 gene. Three hundred and twenty decamer primers were screened and one of them wasidentified as RAPD marker (S411600) linked to Pm18. Using the F2 mapping population fromthe cross Pm18Chancellor, the marker S411600 was shown to co-segregate with the genePm18. This marker can be conveniently used for marker-assisted selection in wheatbreeding programs for the identification or pyramiding of Pm18 with other resistancegenes.展开更多
Powdery mildew （Blumeria graminis） is one of the most destructive crop diseases infecting winter wheat plants, and has devastated millions of hectares of farmlands in China. The objective of this study is to detect ...Powdery mildew （Blumeria graminis） is one of the most destructive crop diseases infecting winter wheat plants, and has devastated millions of hectares of farmlands in China. The objective of this study is to detect the disease damage of powdery mildew on leaf level by means of the hyperspectral measurements, particularly using the continuous wavelet analysis. In May 2010, the reflectance spectra and the biochemical properties were measured for 114 leaf samples with various disease severity degrees. A hyperspectral imaging system was also employed for obtaining detailed hyperspectral information of the normal and the pustule areas within one diseased leaf. Based on these spectra data, a continuous wavelet analysis （CWA） was carried out in conjunction with a correlation analysis, which generated a so-called correlation scalogram that summarizes the correlations between disease severity and the wavelet power at different wavelengths and decomposition scales. By using a thresholding approach, seven wavelet features were isolated for developing models in determining disease severity. In addition, 22 conventional spectral features （SFs） were also tested and compared with wavelet features for their efficiency in estimating disease severity. The multivariate linear regression （MLR） analysis and the partial least square regression （PLSR） analysis were adopted as training methods in model mildew on leaf level were found to be closely related with the development. The spectral characteristics of the powdery spectral characteristics of the pustule area and the content of chlorophyll. The wavelet features performed better than the conventional SFs in capturing this spectral change. Moreover, the regression model composed by seven wavelet features outperformed （R2=0.77, relative root mean square error RRMSE=0.28） the model composed by 14 optimal conventional SFs （R2---0.69, RRMSE--0.32） in estimating the disease severity. The PLSR method yielded a higher accuracy than the MLR method. A combination of CWA and PLSR was found to be promising in providing relatively accurate estimates of disease severity of powdery mildew on leaf level.展开更多
Cucumber powdery mildew is one of the most destructive diseases of cucumber throughout the world. In the present study, inheritance of powdery mildew resistance in three crosses, and linkage of resistance with amplifi...Cucumber powdery mildew is one of the most destructive diseases of cucumber throughout the world. In the present study, inheritance of powdery mildew resistance in three crosses, and linkage of resistance with amplified fragment length polymorphism （AFLP） markers are studied to formulate efficient strategies for breeding cultivars resistant to powdery mildew. The joint analysis of multiple generations and AFLP technique has been applied in this study. The best model is the one with two major genes, additive, dominant, and epistatic effects, plus polygenes with additive, dominant, and epistatic effects （E-l-0 model）. The heritabilities of the major genes varied from 64.26% to 97.82%, and susceptibility was incompletely dominant for the two major genes in the three crosses studied. The additive effects of the two major genes and the dominant effect of the second major gene were high, and the epistatic effect of the additive-dominant between the two major genes was the highest in cross I . In cross II, the absolute value of the additive effect, dominant effect, and potential ratio of the first major gene were far higher than those of the second major gene, and the epistatic effect of the additive-additive was the highest. The genetic parameters of the two major genes in cross III were similar to those in cross II. Correlation and regression analyses showed that marker E25/M63-103 was linked to a susceptible gene controlling powdery mildew resistance. The marker could account for 19.98% of the phenotypic variation. When the marker was tested on a diverse set of 29 cucumber lines, the correlation between phenotype and genotype was not significant, which suggested cultivar specialty of gene expression or different methods of resistance to powdery mildew. The target DNA fragment was 103 bp in length, and only a small part was found to be homologous to DNA in the other species evaluated, which indicated that it was unique to the cucumber genome.展开更多
Mixtures composed of five wheat cultivars,Jingshuang 16,Jing 411,Jingdong 8,Lunxuan 987,and Baofeng 104,with different levels of resistance against powdery mildew were tested for their potential containment of the dis...Mixtures composed of five wheat cultivars,Jingshuang 16,Jing 411,Jingdong 8,Lunxuan 987,and Baofeng 104,with different levels of resistance against powdery mildew were tested for their potential containment of the disease development in the field and for the influence on grain yield and the content of crude protein in the years 2007 and 2010.The plots were inoculated artificially with mixed isolates collected in the fields and propagated in the greenhouse and the disease was scored in 7 d interval during the two growing seasons.It was indicated that certain combinations,e.g.,Jingdong 8：Lunxuan 987,Jingdong 8：Baofeng 104,and Jing 411：Jingdong 8：Baofeng 104,showed positive efficacy on the mildew.The cultivar combinations tested in 2007 showed increase of grain yield,while most of the combinations tested in 2010 did not show the increase.The differences of the increases or decreases were not statistically significant except combinations Jing 411：Jingdong 8：Baofeng104,Jingshuang16：Jingdong8：Lunxuang 987 and Jingshuang 16：Jingdong 8：Lunxuan 987：Baofeng 104,which showed the decrease of the grain yield.The mixtures did not show influence on the content of crude protein in grain.More cultivar combinations need to be tested.展开更多
Different concentrations of jasmonic acid(JA)and benzothiadiazole(BTH) were sprayed on 2-year-old Rosa rugosa‘Plena’ seedlings. The induced resistance of JA and BTH to Sphaerotheca pannosa(Wallr.) and the changes of...Different concentrations of jasmonic acid(JA)and benzothiadiazole(BTH) were sprayed on 2-year-old Rosa rugosa‘Plena’ seedlings. The induced resistance of JA and BTH to Sphaerotheca pannosa(Wallr.) and the changes of their related physiological indices were investigated. Results showed that JA and BTH treatments had inhibitory impacts on S. pannosa infection. The optimal concentration of JA and BTH was 0.5 mmol/L for the disease-resistance induction of the leaves, its inductive effect was up to 66.36% for BTH and 54.49% for JA. Our results confirmed that exogenous JA and BTH significantly improved R. rugose ‘Plena’ resistance to S. pannosa. When treated with JA and BTH, activities of the three defense enzymes(POD, PPO, and PAL) increased significantly.Contents of total phenolics, flavonoids, and lignin also increased significantly. It is inferred from these results that exogenous JA and BTH could improve the resistance of R.rugose ‘Plena’ to S. pannosa through enhancing activities of the defensive enzymes and accumulation of secondary metabolites in the leaves.展开更多
基金This research was supported by the National Key Research and Development Program of China(2021YFD1200600)the National Natural Science Foundation of China(32272105).
文摘Powdery mildew,caused by Blumeria graminis f.sp.tritici(Bgt),is a devastating disease that seriously threatens wheat yield and quality.To control this disease,host resistance is the most effective measure.Compared with the resistance genes from common wheat,alien resistance genes can better withstand infection of this highly variable pathogen.Development of elite alien germplasm resources with powdery mildew resistance and other key breeding traits is an attractive strategy in wheat breeding.In this study,three wheat-rye germplasm lines YT4-1,YT4-2,and YT4-3 were developed through hybridization between octoploid triticale and common wheat,out of which the lines YT4-1 and YT4-2 conferred adult-plant resistance(APR)to powdery mildew while the line YT4-3 was susceptible to powdery mildew during all of its growth stages.Using genomic in situ hybridization,multi-color fluorescence in situ hybridization,multi-color GISH,and molecular marker analysis,YT4-1,YT4-2,and YT4-3 were shown to be cytogenetically stable wheat-rye 6R addition and T1RS.1BL translocation line,6RL ditelosomic addition and T1RS.1BL translocation line,and T1RS.1BL translocation line,respectively.Compared with previously reported wheat-rye derivative lines carrying chromosome 6R,YT4-1 and YT4-2 showed stable APR without undesirable pleiotropic effects on agronomic traits.Therefore,these novel wheat-rye 6R derivative lines are expected to be promising bridge resources in wheat disease breeding.
基金supported by the National Natural Science Foundation of China(32072053,32301800,and 32301923)Wheat Industry Technology System of Shandong Province(SDAIT-01-01)the Key R&D Plan of Shandong Province(2022LZG002-4).
文摘In a wheat breeding line XQ-0508 showing consistent resistance to powdery mildew disease,a recessive gene,designated PmXQ-0508,was identified and mapped to a distal region on chromosome arm 2BS.Of three resistance-associated genes in this region,one encoding a protein kinase was selected as the primary candidate for PmXQ-0508.Ten closely linked DNA markers developed in the study could be used for marker-assisted selection for powdery-mildew resistance in breeding programs.
基金supported by the National Natural Science Foundation of China(32171990 and 32072053)Key Research and Development Program of Zhenjiang(NY2021001)+4 种基金State Key Laboratory of Plant Cell and Chromosome Engineering(PCCE-KF-2021-05 and PCCE-KF-2022-07)State Key Laboratory of Crop Biology in Shandong Agricultural University(2021KF01)Natural Science Foundation of the Jiangsu Higher Education institutions of China(21KJB210004)Open Project Funding of State Key Laboratory of Crop Stress Adaptation and Improvement(CX1130A0920014)Key Research and Development Program of Shandong Province(2020CXGC010805).
文摘Rye(Secale cereale)is a valuable gene donor for wheat improvement,especially for its resistance to diseases.Developing rye-derived resistance sources is important for wheat breeding.In the present study,two wheat-rye derivatives,designated JS016 and JS110,were produced by crossing common wheat cultivar Yangmai 23 with Pakistani rye accession W2A.Using sequential genomic in situ hybridization(GISH)and multicolor fluorescence in situ hybridization(mc-FISH),JS016 and JS110 were identified as a T6BS.6RL translocation line and a T6BS.6BL6RL translocation line,respectively.Ten newly 6RL chromosome arm-specific markers were developed and used to confirm the 6RL translocation.The wheat 55K single-nucleotide polymorphism(SNP)array further verified the molecular cytogenetic identification results above and clarified their breakpoints at 430.9 and 523.0 Mb of chromosome 6B in JS016 and JS110,respectively.Resistance spectrum and allelism test demonstrated that JS016 and JS110 possessed novel powdery mildew resistance gene(s)that was derived from the 6RL translocation but differed from Pm20.Moreover,JS016 and JS110 had better agronomic traits than the previously reported 6RL translocation line carrying Pm20.To efficiently transfer and detect the 6RL translocation from JS016 and JS110,one 6RL-specific Kompetitive allele specific PCR(KASP)marker was developed and validated in high throughput marker-assisted selection(MAS).
文摘Common wheat (Triticum aestivum L.) is one of the most important food crops. Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is one of the most serious diseases on wheat. In this study, the changes of endogenous bacteria in root, stem and leaf tissues of wheat infected and uninfected with powdery mildew were measured based on 16S rDNA. Integration, OTU cluster analysis, taxonomic analysis, diversity index, Shannon-Index curve, Rank-Abundance curve and PCoA analysis were carried out for each sample, and the roots, stems and leaves of different tissue parts were classified and summarized. The results showed that the infection of wheat powdery mildew had a certain effect on endophytic bacteria in stem tissue. There are also differences in the control and treatment of leaf tissue and root tissue. This indicated that endophytic bacteria were distributed differently in different parts of wheat.
基金the‘JBGS’Project of Seed Industry Revitalization in Jiangsu Province(JBGS(2021)013)National Natural Science Foundation of Jiangsu Province for Young Scholars(BK20170176)+2 种基金National Natural Science Foundation of China(30771165)the Ministry of Science and Technology of China(2016YFD0101004)Jiangsu Collaborative Innovation Initiative for Modern Crop Production.
文摘Powdery mildew caused by Blumeria graminis f.sp.tritici(Bgt)is a destructive wheat disease.Although it can be easily overcome by deployment of resistance genes,the resistance is often quickly compromised by pathogen virulence.Thus,exploration and characterization of new resistance genes is always ongoing.Line NJ3946 derived from a cross of einkorn wheat accessions TA2032 and M389 showed resistance to powdery mildew.Inheritance analysis of an F2 population derived from a cross of NJ3946 and M389 suggested that the resistance was conferred by a dominant allele.With polymorphic markers identified through bulked segregant analysis(BSA),this gene was mapped to a novel locus on chromosome 3A,and was designated as PmNJ3946.Bulked segregant RNA-seq analysis(BSR-seq)was conducted to obtain more closely linked markers,which allowed delimitation of the PMNJ3946 locus to a 0.9 cM interval covering a physical distance of less than 1 Mb.PMNJ3946 was flanked by Xwgrc5153 and SNP-derived marker CHS21_3A008915069,and co-segregated with SNP-derived markers CHS21_3A008939814 and CHS21_3A008943175.The PmNJ3946 discovery expands the diversity of powdery mildew resistance genes and is useful for wheat breeding.
基金supported by grants from“Cataloguing,flora study and database establishment of mini-type fungi in Northeast Asia”from the Northeast Asia Biodiversity Research Center。
文摘Chinese peony(Paeonia lactiflora Pall.)is both medicinally and aesthetically beneficial.Powdery mildew is a common fungal disease that seriously jeopardizes the value of numerous species,including peonies as a crop.In order to provide a basis for the prevention and treatment of peony powdery mildew,we examined the microbial diversity,the malondialdehyde(MDA)concentrations and antioxidant enzyme activities of peony leaves infected with three levels of powdery mildew to determine any modifications to the leaf's antioxidant enzyme systems and microbial community structure following the onset of disease.The results show that the MDA content rose as the degree of infection became worse.Antioxidant enzyme activity rose and then declined.Following the initiation of powdery mildew,fungal community diversity decreased,whereas there was not any appreciable change in bacterial communities according to microbial diversity sequencing.The relative abundance of more than half of fungal species decreased,with the bacterial genera displaying both abundant and diminished communities with less pronounced alterations in their community structure after the disease spread.Significant different taxa that were critical to the organization of each microbiome were found.Correlation analysis showed that the relative abundance of powdery mildew pathogenic fungal genus Erysiphe was correlated with those of 11 fungal genera and one bacterial genus.Among them,Aureobasidium,Neosetophoma and Sclerostagonospora showed significant positive correlations with Erysiphe and MDA.
文摘Sunflower is one of the most used commercial oilseed crops and suffers due to Powdery mildew. RNA sequence alteration occurs due to RNA editing which is a post transcriptional modification. It causes a deviation from the genomic DNA sequence resulting in RNA-DNA differences. Accurate study of RNA editing events in diverse species is possible by NGS based methods. Here, we performed RNA sequencing of 12 leaf transcriptomes, which include three genotypes of Helianthus annuus (2023B, TX16R and ID25), H. debilis, H. niveus, and H. praecox along with their respective powdery mildew pathogen infected variants and systematically analysed the mitochondrial RNA editing events using computational reference-based mapping approach. We discovered 687 editing sites, 220 editing events in the protein-coding regions, among all species and genotypes considered in this study. These included “C to U” and “U to C” RNA editing events. On further analysis, we observed that these editing events include 14 different types of amino acid changes that involve the creation of two stop codon events. The conserved editing sites identified were 247 accounting for ~36% of all the editing sites identified. This study provides a detailed picture of the Helianthus species’ mitochondrial RNA editing status. We have identified and characterized for the first time, genotype-specific, species-specific, and stress-specific RNA editing events which may be useful as a potential source for stress-responsive studies in the future.
基金the NSCF(Nos.31360272&31870285)Talent Special Project of Guizhou Academy of Agricultural Sciences(No.2022-02)Talent Base for Germplasm Resources Utilization and Innovation of Characteristic Plant in Guizhou(Grant No.RCJD2018-14).
文摘Various strains of powdery mildew(PM),a notorious plant fungal disease,are prevalent and pose a significant threat to plant health.To control PM,transgenic technology can be used to cultivate more resistant plant varieties.In the present study,we utilized the rapid amplification of cDNA ends(RACE)technique to clone the full-length cDNA sequence of the EuCHIT30.7 gene to explore plant genes with disease resistance functions.Bioinformatics analysis revealed that this gene belongs to the GH18 family and is classified as a class III chitinase.The EuCHIT30.7 gene is expressed throughout the Eucommia ulmoides plant,with the most abundant expression in male flowers.Subcellular localization analysis indicated that the protein encoded by this gene was detected within both the cell membrane and cytoplasm.Upon PM inoculation,overexpression of EuCHIT30.7 in tobacco plants led to a significantly reduced relative lesion area and a decreased spore count compared to both wild-type and empty vector control plants.Activities of the protective enzymes,namely,peroxidase(POD),superoxide dismutase(SOD),catalase(CAT),and phenylalaninammo-nialyase(PAL),in tobacco plants overexpressing EuCHIT30.7 were significantly greater than those in wild-type and empty vector tobacco plants.Furthermore,the rate of increase in malondialdehyde(MDA)content was significantly lower in tobacco plants expressing EuCHIT30.7 compared to control tobacco plants.In EuCHIT30.7 transgenic tobacco,the expression of pathogen-related protein genes,namely,PR2,PR5,PR1a,PDF1.2,and MLP423,along with the tobacco PM negative regulatory gene,MLO2,were significantly higher compared to control tobacco plants.These findings suggested that EuCHIT30.7 significantly enhances the resistance of tobacco to PM.
基金supported by the National Natural Science Foundation of China(Grant No.31701915)Zhejiang Province Public Welfare Technology Application Research Project(Grant No.LGN19C150007).
文摘Cucumber is an important vegetable worldwide,and powdery mildew(PM)is a common and serious disease of cucumbers.Breeding disease-resistant cucumber varieties is the most advantageous strategy to control this disease.In recent years,exploration and identification of cucumber PM resistance genes have achieved great advancement,and many genes have been cloned and verified using different methods.However,the resistance mechanism of cucumber PM is still unclear,and many ambiguities need to be elucidated urgently.In this review,we summarized the research advances in PM resistance in cucumbers,including genetic analysis,quantitative trait locus mapping,map-based cloning,transcriptomics,mlo-mediated PM resistance,and mining of noncoding RNAs involved in resistance.Finally,the research directions and the problems that need to be solved in the future were discussed.
基金Supported by The Key Project of Science and Technology of HenanProvince(102102110040)Innovation Scientists and the Innovation Fund for Outstanding Scholars of Henan Province(104200510013)~~
文摘[Objective] This study was carried out to determine the induction effect of jasmonic acid（JA）on powdery mildew resistance in wheat,the activation effect on the expressions of plant disease resistance related genes,and to investigate the relationship between the induced resistance and the gene expression patterns.[Method] Three powdery mildew susceptible cultivars of ＂Chinese Spring＂,＂Pumai 9＂ and ＂Zhoumai 18＂ typically representing different phenotypes in the field were employed.The powdery mildew was assessed by detached leaf assay,and real time quantitative RT-PCR was used to determine the expression patterns of 9 disease resistance related genes of PR1（PR1.1）,PR2（β,1-3 glucanase）,PR3（chitinase）,PR4（wheatwin1）,PR5（thaumatin-like protein）,PR9（TaPERO,peroxidase）,PR10,TaGLP2a（germin-like）and Ta-JA2（jasmonate-induced protein）in leaf of the three cultivars.[Result] MeJA application enhanced the powdery mildew resistances of ＂Chinese Spring＂,＂Pumai 9＂ and ＂Zhoumai 18＂.The induced powdery mildew resistance could be detected from 12 h to 96 h after MeJA treatment,and the peak value was at 24 h.Though there were differences between the three cultivars,MeJA significantly effect on the expressions of the 8 disease resistance related genes except TaGLP2a,and the peak values were at 12 h,24 h or 48 h after treatments.The strongest activation of MeJA was on PR9 and PR1 that their expressions could reach more than 100 times of the untreated samples.MeJA strongly activated PR2、PR4、PR5、PR3、PR10 and Ta-JA2,their expression could reach 10 to 70 times,and there was almost no activation effect on TaGLP2a.The induced powdery mildew resistance positively correlated with the induced expressions of the 8 disease related genes.[Conclusion] The induced powdery mildew resistance positively correlated with the induced expressions of the disease related genes.Jasmonate signalling plays a role in defence against Blumeria graminis f.sp.tritici.and future manipulation of this pathway may improve powdery mildew resistance in wheat.
基金Supported by Fund of Guizhou Academy of Agricultural Sciences "Study on Pathogenesis and Chemical Control Techniques of Apple Powdery Mildew in Western Guizhou"[QNKH(Fund)No.2010001]Special Project of Guizhou Academy of Agricultural Sciences "Introduction and Demonstration of Apple Three-excellence Technology"[QNKYZX(2009)No.041]~~
文摘[Objective] This study aimed to screen effective fungicide for prevention and control of apple powdery mildew. [Method] Field efficacy of six kinds of fungi- cides with 18 concentrations against apple powdery mildew was investigated. [Re- sult] 4 000-fold triflumizole WP exhibited the highest control efficacy of 82.96%, fol- lowed by 3 000-fold triflumizole WP with control efficacy of 77.75%, while 800-fold and 1 000-fold 70% thiophanate methyl WP exhibited relatively low control efficacy, which was both lower than 60%. [Conclusion] In actual production, 4 000-fold triflu- mizole WP and 3 000-fold triflumizole WP should be used alternately to control and prevent apple powdery mildew.
基金Supported by Research Foundation of Sichuan Education Department "Utilization of Diversity of Tomato Varieties for Continuous Control of Tomato Disea-ses"(07ZC047)~~
文摘[ Objective ] The paper was to explore the pathogenic mechanism of tomato powdery mildew, and to study the effects of the disease on photosynthetic characteristics of tomato. [ Method ] With four tomato varieties as materials, the pathogen of tomato powdery mildew was artificially inoculated. After the varieties were infected, the parameters including net photosynthetic rate, stomatal conductance and transpiration rate of tomato leaf were measured by Li-6400 portable photo- synthesis detector under natural lighting conditions. [ Result] The net photosynthetic rate, stomatal conductance and transpiration rate of four tomato varieties all decreased after infection. However, the decrease extent of these parameters of four varieties was different. The parameters of seriously damaged Jinyangdajuxdng （ No. 4） and Xinsheng No. 1 （ No. 5 ） decreased greatly, while the parameters of slightly damaged Lujia （ No. 13 ） and improved 98-6 decreased lightly. [ Condu- sion] The results could provide theoretical basis for the study on pathogenic mechanism, new prevention way and resistance breeding of tomato powdery mildew.
基金Supported by National 863 Program of China(2011AA10A106)Director Fund of the Institute of Food Crops+1 种基金Yunnan Academy of Agricultural Sciences(2013LZS003)Program for Science and Technology Innovation Talents of Yunnan Province(2012HC008)~~
文摘Yunmai52, developed by crossing with common wheat-Haynaldia villosa6AL/6VS translocation line 92R149 as a resistant parent in 1992, was a common wheat cultivar approved and released in 2007 in Yunnan Province, China, which is characterized by high resistance to powdery mildew and stripe rust. In this study,an F_2 population derived from a cross K78S/Yunmai52 was constructed to investigate the resistance genes, where K78 S is a wheat male sterile line susceptible to powdery mildew and stripe rust. Phenotypic identification of the parents, F_1 and F_2 populations and chi-square analyses showed that F_1 population was immune to stripe rust and powdery mildew; the segregation ratio of resistance and susceptibility to powdery mildew（χ~2=1.10χ~2_（1,0.05）=3.84） and stripe rust（χ~2=0.15χ~2_（1,0.05）=3.84） fit to a 3：1 ratio in F_2 population, indicating that Yunmai52 harbors a dominant stripe rust resistance gene and a dominant powdery mildew resistance gene. The individuals were further detected with a marker co-segregated with Pm21（SCAR_（1400）） and two markers closely linked with Yr26（XWe173 and Xbarc181）. The results showed that polymorphic bands could be amplified between the parents and between resistance and susceptibility gene pools at the same locus. Randomly 96 individuals of F_2 population were selected for verification. The results showed that the phenotype was significantly correlated with the genotype. The detection accuracy of markers SCAR_（1400）, XWe173 and Xbarc181 was 100%, 97.91% and 92.70%, respectively.Yunmai52 harbored powdery mildew resistance gene Pm21 and stripe rust resistance gene Yr26, which were both derived from 6AL/6VS translocation line 92R149.In addition, the results also demonstrate that Pm21 and Yr26 are two genes conferring durable resistance to powdery mildew and stripe rust in wheat.
基金Supported by the Science and Technology Support Program of Tianjin(15ZCZDNC00120)~~
文摘ln order to explore the design and construction of cucumber powdery mildew warning system in solar greenhouse, internet of things technology was used to conduct the real-time dynamic monitoring of the incidence of cucumber powdery mildew and cucumber growth environment in solar greenhouse. The growth environ-ment included temperature and humidity of air and soil. Logistic regression model was used to construct cucumber powdery mildew warning model. The results showed that humidity characteristic variable （maximum air humidity） and temperature characteristic variable （maximum air temperature） had significant effects on the inci-dence probability of cucumber powdery mildew in solar greenhouse. And it was fea-sible to construct cucumber powdery mildew warning system in solar greenhouse with internet of things.
基金Supported by Students Innovation Fund in Liaocheng UniversityKey topics Projects in Liaocheng University(x061005)Science and Technology Development Program,Education Department of Shandong Province(J09Lc17)~~
文摘[Objective] The study discussed the indoor activity and field control effect of vegetable oil on cucumber powdery mildew.[Method] The cucumber seedlings of Changchunmici were adopted as the material,which were inoculated with the fungus pathogen of cucumber powdery mildew naturally occurred in the field.The indoor protective test and field test were performed respectively to observe the control effects of different plant oils EC on the cucumber powdery mildew.[Result] When six plant oils EC including cottonseed oil,soybean oil,canola oil,corn oil,sesame oil and sunflower oil was diluted into 10 and 5 ml/L,they had better control effect on cucumber powdery mildew.As for the indoor protective effect,the protective effect of the vegetable oil EC was equivalent to the control agent triadimefon EC,the field control effect of vegetable oil EC was in the range of 60%-75%,which was consistent with 69%-70% control effect of contrast agent with 1 ml/L triadimefon EC dilution.[Conclusion] All vegetable oils EC had significant control effect on cucumber powdery mildew in the test.
文摘The Pm18 gene of wheat confers resistance to the powdery mildew which is one of the mostserious diseases in many regions of the world. In this study, bulked segregant analysis(BSA) was used to develop randomly amplified polymorphic DNA (RAPD) markers linked toPm18 gene. Three hundred and twenty decamer primers were screened and one of them wasidentified as RAPD marker (S411600) linked to Pm18. Using the F2 mapping population fromthe cross Pm18Chancellor, the marker S411600 was shown to co-segregate with the genePm18. This marker can be conveniently used for marker-assisted selection in wheatbreeding programs for the identification or pyramiding of Pm18 with other resistancegenes.
基金the National Natural Science Foundation of China (41101395, 41071276, 31071324)the Beijing Municipal Natural Science Foundation, China (4122032)the National Basic Research Program of China (2011CB311806)
文摘Powdery mildew （Blumeria graminis） is one of the most destructive crop diseases infecting winter wheat plants, and has devastated millions of hectares of farmlands in China. The objective of this study is to detect the disease damage of powdery mildew on leaf level by means of the hyperspectral measurements, particularly using the continuous wavelet analysis. In May 2010, the reflectance spectra and the biochemical properties were measured for 114 leaf samples with various disease severity degrees. A hyperspectral imaging system was also employed for obtaining detailed hyperspectral information of the normal and the pustule areas within one diseased leaf. Based on these spectra data, a continuous wavelet analysis （CWA） was carried out in conjunction with a correlation analysis, which generated a so-called correlation scalogram that summarizes the correlations between disease severity and the wavelet power at different wavelengths and decomposition scales. By using a thresholding approach, seven wavelet features were isolated for developing models in determining disease severity. In addition, 22 conventional spectral features （SFs） were also tested and compared with wavelet features for their efficiency in estimating disease severity. The multivariate linear regression （MLR） analysis and the partial least square regression （PLSR） analysis were adopted as training methods in model mildew on leaf level were found to be closely related with the development. The spectral characteristics of the powdery spectral characteristics of the pustule area and the content of chlorophyll. The wavelet features performed better than the conventional SFs in capturing this spectral change. Moreover, the regression model composed by seven wavelet features outperformed （R2=0.77, relative root mean square error RRMSE=0.28） the model composed by 14 optimal conventional SFs （R2---0.69, RRMSE--0.32） in estimating the disease severity. The PLSR method yielded a higher accuracy than the MLR method. A combination of CWA and PLSR was found to be promising in providing relatively accurate estimates of disease severity of powdery mildew on leaf level.
文摘Cucumber powdery mildew is one of the most destructive diseases of cucumber throughout the world. In the present study, inheritance of powdery mildew resistance in three crosses, and linkage of resistance with amplified fragment length polymorphism （AFLP） markers are studied to formulate efficient strategies for breeding cultivars resistant to powdery mildew. The joint analysis of multiple generations and AFLP technique has been applied in this study. The best model is the one with two major genes, additive, dominant, and epistatic effects, plus polygenes with additive, dominant, and epistatic effects （E-l-0 model）. The heritabilities of the major genes varied from 64.26% to 97.82%, and susceptibility was incompletely dominant for the two major genes in the three crosses studied. The additive effects of the two major genes and the dominant effect of the second major gene were high, and the epistatic effect of the additive-dominant between the two major genes was the highest in cross I . In cross II, the absolute value of the additive effect, dominant effect, and potential ratio of the first major gene were far higher than those of the second major gene, and the epistatic effect of the additive-additive was the highest. The genetic parameters of the two major genes in cross III were similar to those in cross II. Correlation and regression analyses showed that marker E25/M63-103 was linked to a susceptible gene controlling powdery mildew resistance. The marker could account for 19.98% of the phenotypic variation. When the marker was tested on a diverse set of 29 cucumber lines, the correlation between phenotype and genotype was not significant, which suggested cultivar specialty of gene expression or different methods of resistance to powdery mildew. The target DNA fragment was 103 bp in length, and only a small part was found to be homologous to DNA in the other species evaluated, which indicated that it was unique to the cucumber genome.
基金supported by the National Basic Research Program of China(2006CB100203 and 2011CB100403)the Key Technology R & D Program of China during the 11th Five-Year Plan period(2006BAD08A05)the Special Fund for Agro-Scientific Research in the Public Interest,China(3-15)
文摘Mixtures composed of five wheat cultivars,Jingshuang 16,Jing 411,Jingdong 8,Lunxuan 987,and Baofeng 104,with different levels of resistance against powdery mildew were tested for their potential containment of the disease development in the field and for the influence on grain yield and the content of crude protein in the years 2007 and 2010.The plots were inoculated artificially with mixed isolates collected in the fields and propagated in the greenhouse and the disease was scored in 7 d interval during the two growing seasons.It was indicated that certain combinations,e.g.,Jingdong 8：Lunxuan 987,Jingdong 8：Baofeng 104,and Jing 411：Jingdong 8：Baofeng 104,showed positive efficacy on the mildew.The cultivar combinations tested in 2007 showed increase of grain yield,while most of the combinations tested in 2010 did not show the increase.The differences of the increases or decreases were not statistically significant except combinations Jing 411：Jingdong 8：Baofeng104,Jingshuang16：Jingdong8：Lunxuang 987 and Jingshuang 16：Jingdong 8：Lunxuan 987：Baofeng 104,which showed the decrease of the grain yield.The mixtures did not show influence on the content of crude protein in grain.More cultivar combinations need to be tested.
基金supported by the Science Foundation of Heilongjiang Province of China(No.QC2014C012)the Fundamental Research Funds for the Central Universities(NO.2572016CA11)
文摘Different concentrations of jasmonic acid(JA)and benzothiadiazole(BTH) were sprayed on 2-year-old Rosa rugosa‘Plena’ seedlings. The induced resistance of JA and BTH to Sphaerotheca pannosa(Wallr.) and the changes of their related physiological indices were investigated. Results showed that JA and BTH treatments had inhibitory impacts on S. pannosa infection. The optimal concentration of JA and BTH was 0.5 mmol/L for the disease-resistance induction of the leaves, its inductive effect was up to 66.36% for BTH and 54.49% for JA. Our results confirmed that exogenous JA and BTH significantly improved R. rugose ‘Plena’ resistance to S. pannosa. When treated with JA and BTH, activities of the three defense enzymes(POD, PPO, and PAL) increased significantly.Contents of total phenolics, flavonoids, and lignin also increased significantly. It is inferred from these results that exogenous JA and BTH could improve the resistance of R.rugose ‘Plena’ to S. pannosa through enhancing activities of the defensive enzymes and accumulation of secondary metabolites in the leaves.
