The objective of this study was to characterize yellow (stripe) rust resistance gene(s) in 52 commercial wheat cultivars from Yunnan Province in China, and to provide information for their rational deployment in f...The objective of this study was to characterize yellow (stripe) rust resistance gene(s) in 52 commercial wheat cultivars from Yunnan Province in China, and to provide information for their rational deployment in field. Seedlings of wheat cultivars were inoculated with 25 differential isolates ofPuccinia striiformis from foreign and home to postulate resistance genes to yellow rust, and then validated by pedigree. There were 10 probable resistance genes characterized in these cultivars, in which, Yr9 was most commonly postulated to be present in thirteen cultivars. Yr21, the second, was present in four cultivars. Yr8, the third, were present in three cultivars. Yr6, Yrl 7 and Yr26, the fourth, was present in two cultivars respectively. The other gene(s) such as, Yr2+YrA, Yr7 and Yr27, were only present in single cultivar(s); unknown gene(s) or gene(s) combination(s) were present in 22 cultivars. One cultivar (Yunmai 42) had no resistance gene tested in this study. Cultivars such as Yunmai 52, Mian 1971-98, Kunmai 4, and Yunmai 56 carried effective genes and can be popularized mainly; Yr9 should be planted with other Yr genes. In the meantime other effective genes should be introduced to realize gene diversity for controlling wheat yellow rust. Yunmai 42 should be reduced to avoid rust breakout. Unknown gene cultivars should be utilized and be researched deeply.展开更多
The wheat canopy reflectance spectrum is affected by many internal and external factors such as diseases and growth stage. Separating the effects of disease stress on the crop from the observed mixed signals is crucia...The wheat canopy reflectance spectrum is affected by many internal and external factors such as diseases and growth stage. Separating the effects of disease stress on the crop from the observed mixed signals is crucial for increasing the precision of remote sensing monitoring of wheat stripe rust. The canopy spectrum of winter wheat infected by stripe rust was processed with the difference-in-differences(DID) algorithm used in econometrics. The monitoring accuracies of wheat stripe rust before and after processing with the DID algorithm were compared in the presence of various external factors, disease severity, and several simulated satellite sensors. The correlation between the normalized difference vegetation index processed by the DID algorithm(NDVI-DID) and the disease severity level(SL) increased in comparison with the NDVI before processing. The increase in precision in the natural disease area in the field in the presence of large differences in growth stage, growth, planting, and management of the crop was greater than that in the controlled experiment. For low disease levels(SL < 20%), the R2 of the regression of NDVI-DIDon SL was 38.8% higher than that of the NDVI and the root mean square error(RMSE) was reduced by 11.1%. The increase in precision was greater than that for the severe level(SL > 40%).According to the measured hyperspectral data, the spectral reflectance of three satellite sensor levels was simulated. The wide-band NDVI was calculated. Compared with the wide-band NDVI and vegetation indexes(VI) before DID processing, there were increases in the correlation between SL and the various types of VIS-DID, as well as in the correlation between SL and NDVI-DID. It is feasible to apply the DID algorithm to multispectral satellite data and diverse types of VISfor monitoring wheat stripe rust. Our results improve the quantification of independent effects of stripe rust infection on canopy reflectance spectrum,increase the precision of remote sensing monitoring of wheat stripe rust, and provide a reference for remote sensing monitoring of other crop diseases.展开更多
Stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the major diseases of wheat in China. In order to asses the resistance levels and existing Yr genes among 59 wheat cultivars (lines) from the Pac...Stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the major diseases of wheat in China. In order to asses the resistance levels and existing Yr genes among 59 wheat cultivars (lines) from the Pacific Northwest (PNW) of the United States, to provide resistance resources for genetic improvement of wheat stripe rust resistance in China, 59 wheat cultivars (lines) from PNW of the United States were infected by 3 mixed races of predominant Chinese stripe rust races CRY31, CRY32, and CRY33 to evaluate their resistance at seedling and adult plant stages, and screened with molecular markers tightly linked to currently effective all-stage resistance genes YrlO, Yrl5 and adult plant resistance genes Yrl8, Yr39. Of 59 American cultivars (lines), five cultivars (lines), Expresso, 02W50076, ACS52610, WA008012, and WA00801833, had all-stage resistance, showing resistance to mixed races of CRY31, CRY32, and CRY33 at both seedling and adult plant stages. 33 cultivars (lines) had adult plant resistance, only showing resistance to stripe rust at adult stage. Based on the molecular screening, none of the 59 PNW cultivars (lines) had the polymorphic bands of linked markers to YrlO. There were 12, 33 and 29 cultivars (lines) which bad polymorphic bands of linked markers to Yr15, Yr18 and Yr39, accounting for 20, 55 and 49% of the 59 PNW cultivars (lines), respectively. All these results suggested that Yr15, Yr18 and Yr39 were widespread among PNW cultivars (cultivars) and could be utilized in Chinese wheat stripe rust resistance breeding.展开更多
Puccinia striiformis Westend.f.sp.tritici Erikss.(Pst)infects wheat and causes stripe rust.The rust is heteroecious with wheat as the primary uredinial and telial host and barberry(Berberis spp.)as the alternate pycni...Puccinia striiformis Westend.f.sp.tritici Erikss.(Pst)infects wheat and causes stripe rust.The rust is heteroecious with wheat as the primary uredinial and telial host and barberry(Berberis spp.)as the alternate pycnial and aecial host.More than 40 Berberis species have been identified as alternate hosts for Pst,and most of these are Chinese Berberis species.However,little is known about Berberis species or their geographic distributions in the Yunnan-Guizhou plateau in southwestern China.The Yunnan-Guizhou plateau is considered to be an important and relatively independent region for the evolution of the wheat stripe rust pathogen in China because the entire disease cycle can be completed within the region.In this study,we conducted a survey of barberry plants in the Yunnan-Guizhou plateau and identified the eight Pst-susceptible Berberis species under controlled conditions,including B.julianae,B.tsienii,B.veitchii,B.wilsonae,B.wilsonae var.guhtzunica,B.franchetiana,B.lepidifolia and B.pruinosa.These species are reported here for the first time to serve as alternate hosts for the wheat stripe rust pathogen under controlled conditions.展开更多
In order to realize monitoring and early warning and comprehensive management of wheat stripe rust and to reduce its occurrence in Nanchong City, the occurrence and epidemic regularity of wheat stripe rust in Nanchong...In order to realize monitoring and early warning and comprehensive management of wheat stripe rust and to reduce its occurrence in Nanchong City, the occurrence and epidemic regularity of wheat stripe rust in Nanchong was studied by system monitoring and general survey, resistance identification, physiological race monitoring and meteorological data analysis. The initial occurrence location and spreading pathway of Puccinia striiformis f. sp. tritici (Pst) were first verified; there were two infection peaks of wheat stripe rust in Nanchong and one to three epidemic peaks in fields, in which the occurrence area of the first epidemic peak played a pivotal role in disease prevalence in that year; the cumulative occurrence area in late January was positively correlated with annual occurrence area, with the correlation coefficient of 0.769 ; the prediction model for infected field rate, diseased plant rate and annual occurrence area was established. The internal reason for heavy occurrence and prevalence of wheat stripe rust in Nanchong was the decline or loss of wheat resistance against stripe rust, as well as the appearance of physiological races of Pst, which later became dominant races. Large fluctuation of temperature in warm winter and spring and more fog and dew days were external reasons responsible for prevalence of stripe rust. From 2002 to 2014 ,the accuracy rate of short-term prediction of wheat stripe rust reached 100%, while that of me- dium-term and long-term prediction reached over 98% and 95%, respectively, 5% -15% higher than that of the years before 1998.展开更多
Stripe rust caused by Puccinia striiformis f. sp. tritici is an important wheat disease worldwide that is greatly influenced by environmental conditions. Ultraviolet B(UV-B) radiation is one important environmental fa...Stripe rust caused by Puccinia striiformis f. sp. tritici is an important wheat disease worldwide that is greatly influenced by environmental conditions. Ultraviolet B(UV-B) radiation is one important environmental factor affecting the occurrence and epidemiology of wheat stripe rust. Investigating UV-B radiation effects on the epidemiology of stripe rust may be conducive to monitoring and predicting this disease. In this study, wheat seedlings were exposed to UV-B radiation during different periods under laboratory conditions and radiation effects on epidemiological components of wheat stripe rust were investigated. Results showed that incubation period was shortened, and the infection efficiency, sporulation quantity and disease index increased when UV-B radiation was performed only pre-inoculation. When the UV-B radiation was performed only postinoculation or both pre-and post-inoculation, the incubation period was prolonged, and the infection efficiency, sporulation quantity and disease index were reduced. When healthy wheat seedlings were inoculated using urediospores collected from wheat leaves irradiated by UV-B only post-inoculation or both pre-and post-inoculation, infection efficiency, sporulation quantity and disease index were also reduced. However, in the latter, the disease incubation period did not differ under varying UV-B radiation intensities compared to that when wheat leaves were not treated with UV-B radiation. Overall, the effects of direct exposure of wheat plants to UV-B radiation with different intensities in different periods on epidemiological components of wheat stripe rust were systematically explored, and the results suggest that the effects of UV-B radiation increased gradually with the increase of UV-B radiation intensity. This information provides a basis for monitoring and predicting this disease as well as for conducting further studies on pathogen virulence variation.展开更多
Puccinia striiformis f. sp. tritici (Pst) is one of the pathogenic fungi on wheat, caused stripe rust that is a great threat for wheat production all over the world. Intensive efforts have been made to study genetics ...Puccinia striiformis f. sp. tritici (Pst) is one of the pathogenic fungi on wheat, caused stripe rust that is a great threat for wheat production all over the world. Intensive efforts have been made to study genetics of wheat resistance to this disease, but few on avirulence of the pathogen due mainly to the nature of obligate biotrophism and the lack of systems for studying its genetics and molecular manipulations. To overcome these limitations, a natural Pst population comprising 352 isolates representative of a diverse virulence spectrum was genotyped using 97 secreted protein-single nucleotide polymorphism (SP-SNP) markers to identify candidate avirulence genes using association analysis. Among avirulence genes corresponding to 19 resistance genes, significantly associated SP-SNP markers were detected for avirulence genes AvYr1, AvYr2, AvYr6, AvYr7, AvYr8, AvYr44, AvYrExp2, AvYrSP, and AvYrTye. These results indicate that association analysis can be used to identify markers for avirulence genes. This study has laid the foundation for developing more SP-SNPs for mapping avirulence genes using segregating populations that can be generated through sexual reproduction on alternate hosts of the pathogen.展开更多
The biotrophic fungus Puccinia striiformis f. sp. tritici is the causal agent of the yellow rust in wheat. Between the years 2010–2013 a new strain of this pathogen(Warrior/Ambition),against which the present cultiva...The biotrophic fungus Puccinia striiformis f. sp. tritici is the causal agent of the yellow rust in wheat. Between the years 2010–2013 a new strain of this pathogen(Warrior/Ambition),against which the present cultivated wheat varieties have no resistance, appeared and spread rapidly. It threatens cereal production in most of Europe. The search for sources of resistance to this strain is proposed as the most efficient and safe solution to ensure high grain production. This will be helped by the development of high performance and low cost techniques for field phenotyping. In this study we analyzed vegetation indices in the Red,Green, Blue(RGB) images of crop canopies under field conditions. We evaluated their accuracy in predicting grain yield and assessing disease severity in comparison to other field measurements including the Normalized Difference Vegetation Index(NDVI), leaf chlorophyll content, stomatal conductance, and canopy temperature. We also discuss yield components and agronomic parameters in relation to grain yield and disease severity.RGB-based indices proved to be accurate predictors of grain yield and grain yield losses associated with yellow rust(R2= 0.581 and R2= 0.536, respectively), far surpassing the predictive ability of NDVI(R2= 0.118 and R2= 0.128, respectively). In comparison to potential yield, we found the presence of disease to be correlated with reductions in the number of grains per spike, grains per square meter, kernel weight and harvest index. Grain yield losses in the presence of yellow rust were also greater in later heading varieties. The combination of RGB-based indices and days to heading together explained 70.9% of the variability in grain yield and 62.7% of the yield losses.展开更多
Yellow rust of wheat (caused by Puccinia striiformis Westend. f. sp. tritici Eriks.) has been periodically epidemic and severely damaged wheat production in China. The development of resistant cultivars could be an ...Yellow rust of wheat (caused by Puccinia striiformis Westend. f. sp. tritici Eriks.) has been periodically epidemic and severely damaged wheat production in China. The development of resistant cultivars could be an effective way to reduce yield losses of wheat caused by yellow rust. Rust reaction tests and genetic analysis indicated that M08, the synthetic hexaploid wheat derived from hybridization between Triticum durum (2n = 6X = 28; genome AABB) and Aegilops tauschii (2n = 2X = 14; genome DD), showed resistance to current prevailing yellow rust races at seedling stage, which was controlled by a single dominant gene, designated as YrAm. Bulked segregant analysis was used to identify microsatellite markers linked to gene YrAm in an F2 population derived from cross M08 (resistant) × Jinan 17 (susceptible). Three microsatellite marker loci Xgwm77, Xgwm285, and Xgwml31 located on chromosome 3B were mapped to the YrAm locus. Xgwml31 was the closest marker locus and showed a linkage distance of 7.8 cM to the resistance locus. Thus, it is assumed that YrAm for resistance to yellow rust may be derived from Triticum durum and is located on the long arm of chromosome 3B.展开更多
The aim of this study is to clarify the application effect of pesticide decrement synergist ' Jijian' on wheal stripe lUSt. Sampling investigation, randomized block design and statistic analysis were carried out to ...The aim of this study is to clarify the application effect of pesticide decrement synergist ' Jijian' on wheal stripe lUSt. Sampling investigation, randomized block design and statistic analysis were carried out to find out the field efficacy of adding ' Jijian' to triadimefon WP and propiconazole EC on controlling wheat stripe rust. The results showed that during the epidemic period of stripe rust, the control effects on the 7^th and the 19^th d reached more than 93% and 100% , respectively, by the application of 15% triadimefon WP of 1 200 g/hm^2 and 25% propiconazole EC of 600 mlhm^2 , respectively for 2 times ; when 15% triadimefon WP of 840 g/hm^2 + ' Jijian' of 225 g/hm^2 or 25 % propiconazole EC of 420 mlhm^2 + ' Jijian' of 225 g/hm^2 were applied ( adding ' Jijian' and reducing the dosage of the 2 pesticides by 30% ) , the control effect on the 7^th d was 89.4% and 91.7% , respectively, while the control effect on the 19a' d was 99.8 - 100% ; when 15% triadimefon WP of 720 - 600 g/hm^2 + ' Jijian' of 225 g/hm^2 or 25% propiconazole EC 360 - 300 mlhm^2 + ' Jijian' of 225 g/hm^2 were applied ( adding ' Jijian' and reducing the dosage of the 2 pesticides by 40% - 50% ) , the control effect on the 7a' day reached more than 78.0% , while the control effect on the 19^th day was 97.7% - 99.8%. There was no significant difference on the control effect at the 7^th d between the treatments using the 2 pesticides alone and the treatments adding ' Jijian' and reducing the dosage of the 2 pesticides by 30%, but all had significant differences from the treatments adding ' Jijian' and reducing the dosage of the 2 pesticides by40% -50%. There was no significant difference on the control effect of the 19^th d among different treatments. Therefore, if the disease is not serious, the application of ' Jijian' can reduce the application amounts of pesticides by 40% -50%, that is, 15% triadimefon WP of 720 -600 g/hm^2 + ' Jijian' of 225 g/hm^2 or 25 % propiconazole EC of 360- 300 ml/hm^2 + ' Jijian' of 225 g/hm^2, which is helpful to reduce the pesticide application amounts and pesticide residue pollution, and save the control costs.展开更多
Wheat powdery mildew and stripe rust are the major diseases in wheat producing area in Xinjiang.To obtain wheat germplasm resources and varieties resistant to powdery mildew and rust,36 high-generation stable strains ...Wheat powdery mildew and stripe rust are the major diseases in wheat producing area in Xinjiang.To obtain wheat germplasm resources and varieties resistant to powdery mildew and rust,36 high-generation stable strains of Xinjiang winter wheat were evaluated using the method of natural inducement from 2018 to 2020.A total of 5 strains with high resistance to powdery mildew,4 strains with slow stripe rust and 1 strain with resistance to powdery mildew and adult plant slow stripe rust were obtained.And the parental combination of disease-resistant varieties was analyzed.These studies will provide theoretical basis for the breeding of resistant wheat varieties in Xinjiang.展开更多
Wheat stripe rust,caused by Puccinia striiformis Westend. f. sp. tritici Erikss.( Pst),is one of the most destructive diseases of wheat( Triticum aestivum L.) worldwide. Sichuan province plays an important role in...Wheat stripe rust,caused by Puccinia striiformis Westend. f. sp. tritici Erikss.( Pst),is one of the most destructive diseases of wheat( Triticum aestivum L.) worldwide. Sichuan province plays an important role in stripe rust epidemic in China. To identify and evaluate wheat stripe rust resistance in Sichuan Province,134 wheat cultivars( lines) were inoculated with seven Pst races at seedling stage and adult stage. The results indicated that the resistance frequencies of wheat cultivars( lines) against seven races CYR31,Su11-7,CYR29,Su11-4,CYR32,CYR33 and V26 were 92. 4%,92. 5%,89. 3%,89. 4%,87. 3%,85. 0% and 82. 8%,respectively. Among 134 materials,76( 56. 0%) performed resistance against all tested races both in seedling and adult stages. The virulence of new pathogenic type V26 of Pst on wheat cultivars( lines) was stronger than the dominant races CYR32 and CYR33. All wheat cultivars( lines) were classified into three types according to analysis of resistance spectrum; 66. 4% of cultivars( lines) showed all-stage resistance,17. 9% were adult-plant resistance,and 15. 7% were susceptible. This indicated that although the overall resistance level of wheat cultivars( lines) in Sichuan Province was very high,the resistance type was simple. Therefore,it is important to identify new resistance genes and enhance resistance gene diversity. Meanwhile,pyramiding breeding of all-stage resistance gene and adult-plant resistance gene could be gradually developed,to achieve durable resistance of wheat cultivars(lines) against stripe rust in Sichuan Province.展开更多
Loss of variety resistance to stripe rust (Puccinia striiformis Westend f. sp.tritici) is an important factor causing massive periodical epidemic of rust in wheat production. Creation and development of new races of...Loss of variety resistance to stripe rust (Puccinia striiformis Westend f. sp.tritici) is an important factor causing massive periodical epidemic of rust in wheat production. Creation and development of new races of rust pathogen have led to serious crisis of resistance loss in widely planted varieties. This has quickened the search for new resistance resources. Molecular marker could facilitate the identification of the location of novel genes. A line A-3 with high resistance (immune) to currently epidemic yellow rust races (CY29, 31, 32) was screened out in offspring of Triticum aestivura x Thinopyrum ponticum. Segregation in F2 and BC1 populations indicated that the resistance was controlled by two independent genes: one dominant and one recessive. SSR markers were employed to map the two resistant genes in the F2 and BC1 populations. A marker WMC477-167bp located on 2BS was linked to the dominant gene with genetic distance of 0.4 cM. Another marker WMC364-2os bp located on 7BS was linked to the recessive-resistant gene with genetic distance of 5.8 cM. The two genes identified in this paper might be two novel stripe rust resistant genes, which were temporarily designated as YrTpl and YrTp2, respectively. The tightly linking markers facilitate transfer of the two resistant genes into the new varieties to control epidemic of yellow rust.展开更多
基金support by the Ministry of Science and Technology,China (2011CB100403)the Ministry of Agriculture,China (200903035)the Special Project from State Key Laboratory for Biology of Plant Diseases and Insect Pests,Chinese Academy of Agricltural Sciences (SKL2009OP09)
文摘The objective of this study was to characterize yellow (stripe) rust resistance gene(s) in 52 commercial wheat cultivars from Yunnan Province in China, and to provide information for their rational deployment in field. Seedlings of wheat cultivars were inoculated with 25 differential isolates ofPuccinia striiformis from foreign and home to postulate resistance genes to yellow rust, and then validated by pedigree. There were 10 probable resistance genes characterized in these cultivars, in which, Yr9 was most commonly postulated to be present in thirteen cultivars. Yr21, the second, was present in four cultivars. Yr8, the third, were present in three cultivars. Yr6, Yrl 7 and Yr26, the fourth, was present in two cultivars respectively. The other gene(s) such as, Yr2+YrA, Yr7 and Yr27, were only present in single cultivar(s); unknown gene(s) or gene(s) combination(s) were present in 22 cultivars. One cultivar (Yunmai 42) had no resistance gene tested in this study. Cultivars such as Yunmai 52, Mian 1971-98, Kunmai 4, and Yunmai 56 carried effective genes and can be popularized mainly; Yr9 should be planted with other Yr genes. In the meantime other effective genes should be introduced to realize gene diversity for controlling wheat yellow rust. Yunmai 42 should be reduced to avoid rust breakout. Unknown gene cultivars should be utilized and be researched deeply.
基金supported by the National Natural Science Foundation of China (42171394, 41601467)。
文摘The wheat canopy reflectance spectrum is affected by many internal and external factors such as diseases and growth stage. Separating the effects of disease stress on the crop from the observed mixed signals is crucial for increasing the precision of remote sensing monitoring of wheat stripe rust. The canopy spectrum of winter wheat infected by stripe rust was processed with the difference-in-differences(DID) algorithm used in econometrics. The monitoring accuracies of wheat stripe rust before and after processing with the DID algorithm were compared in the presence of various external factors, disease severity, and several simulated satellite sensors. The correlation between the normalized difference vegetation index processed by the DID algorithm(NDVI-DID) and the disease severity level(SL) increased in comparison with the NDVI before processing. The increase in precision in the natural disease area in the field in the presence of large differences in growth stage, growth, planting, and management of the crop was greater than that in the controlled experiment. For low disease levels(SL < 20%), the R2 of the regression of NDVI-DIDon SL was 38.8% higher than that of the NDVI and the root mean square error(RMSE) was reduced by 11.1%. The increase in precision was greater than that for the severe level(SL > 40%).According to the measured hyperspectral data, the spectral reflectance of three satellite sensor levels was simulated. The wide-band NDVI was calculated. Compared with the wide-band NDVI and vegetation indexes(VI) before DID processing, there were increases in the correlation between SL and the various types of VIS-DID, as well as in the correlation between SL and NDVI-DID. It is feasible to apply the DID algorithm to multispectral satellite data and diverse types of VISfor monitoring wheat stripe rust. Our results improve the quantification of independent effects of stripe rust infection on canopy reflectance spectrum,increase the precision of remote sensing monitoring of wheat stripe rust, and provide a reference for remote sensing monitoring of other crop diseases.
基金funded by the National Natural Science Foundation of China(30971778)Open Fund Project of State Key Laboratory for Biology of Plant Diseases and Insect Pests,China(2008.1-2008.12)China Postdoctoral Science Foundation(200902552)
文摘Stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the major diseases of wheat in China. In order to asses the resistance levels and existing Yr genes among 59 wheat cultivars (lines) from the Pacific Northwest (PNW) of the United States, to provide resistance resources for genetic improvement of wheat stripe rust resistance in China, 59 wheat cultivars (lines) from PNW of the United States were infected by 3 mixed races of predominant Chinese stripe rust races CRY31, CRY32, and CRY33 to evaluate their resistance at seedling and adult plant stages, and screened with molecular markers tightly linked to currently effective all-stage resistance genes YrlO, Yrl5 and adult plant resistance genes Yrl8, Yr39. Of 59 American cultivars (lines), five cultivars (lines), Expresso, 02W50076, ACS52610, WA008012, and WA00801833, had all-stage resistance, showing resistance to mixed races of CRY31, CRY32, and CRY33 at both seedling and adult plant stages. 33 cultivars (lines) had adult plant resistance, only showing resistance to stripe rust at adult stage. Based on the molecular screening, none of the 59 PNW cultivars (lines) had the polymorphic bands of linked markers to YrlO. There were 12, 33 and 29 cultivars (lines) which bad polymorphic bands of linked markers to Yr15, Yr18 and Yr39, accounting for 20, 55 and 49% of the 59 PNW cultivars (lines), respectively. All these results suggested that Yr15, Yr18 and Yr39 were widespread among PNW cultivars (cultivars) and could be utilized in Chinese wheat stripe rust resistance breeding.
基金the National Key R&D Program of China(2018YFD0200500)the National Natural Science Foundation of China(31960524,31071641 and 32072358)+1 种基金the Fundamental Research Funds for the Central Universities(2452019046)the Natural Science Basic Research Plan in Shaanxi Province of China(2020JZ-15,2017JM3006)。
文摘Puccinia striiformis Westend.f.sp.tritici Erikss.(Pst)infects wheat and causes stripe rust.The rust is heteroecious with wheat as the primary uredinial and telial host and barberry(Berberis spp.)as the alternate pycnial and aecial host.More than 40 Berberis species have been identified as alternate hosts for Pst,and most of these are Chinese Berberis species.However,little is known about Berberis species or their geographic distributions in the Yunnan-Guizhou plateau in southwestern China.The Yunnan-Guizhou plateau is considered to be an important and relatively independent region for the evolution of the wheat stripe rust pathogen in China because the entire disease cycle can be completed within the region.In this study,we conducted a survey of barberry plants in the Yunnan-Guizhou plateau and identified the eight Pst-susceptible Berberis species under controlled conditions,including B.julianae,B.tsienii,B.veitchii,B.wilsonae,B.wilsonae var.guhtzunica,B.franchetiana,B.lepidifolia and B.pruinosa.These species are reported here for the first time to serve as alternate hosts for the wheat stripe rust pathogen under controlled conditions.
基金Supported by Comprehensive Prevention and Treatment Monitoring Station of Inoculum Source of Wheat Stripe Rust in Nanchong City(NYBNJH[2003]104)Notice of the Ministry of Agriculture on Identification of the First Batch of National Modern Agricultural Demonstration Zone(NJF[2010]22)+2 种基金Occurrence and Epidemic Regularity of Wheat Stripe Rust and Its Integrated Control Technology in Nanchong City(N1998-ZC018)Fundamental Research Funds for the Central Universities(XDJK2015C060,SWU114046,2362015xk04)Open Project Program of State Key Laboratory of Crop Stress Biology for Arid Areas(CSBAA2015009)
文摘In order to realize monitoring and early warning and comprehensive management of wheat stripe rust and to reduce its occurrence in Nanchong City, the occurrence and epidemic regularity of wheat stripe rust in Nanchong was studied by system monitoring and general survey, resistance identification, physiological race monitoring and meteorological data analysis. The initial occurrence location and spreading pathway of Puccinia striiformis f. sp. tritici (Pst) were first verified; there were two infection peaks of wheat stripe rust in Nanchong and one to three epidemic peaks in fields, in which the occurrence area of the first epidemic peak played a pivotal role in disease prevalence in that year; the cumulative occurrence area in late January was positively correlated with annual occurrence area, with the correlation coefficient of 0.769 ; the prediction model for infected field rate, diseased plant rate and annual occurrence area was established. The internal reason for heavy occurrence and prevalence of wheat stripe rust in Nanchong was the decline or loss of wheat resistance against stripe rust, as well as the appearance of physiological races of Pst, which later became dominant races. Large fluctuation of temperature in warm winter and spring and more fog and dew days were external reasons responsible for prevalence of stripe rust. From 2002 to 2014 ,the accuracy rate of short-term prediction of wheat stripe rust reached 100%, while that of me- dium-term and long-term prediction reached over 98% and 95%, respectively, 5% -15% higher than that of the years before 1998.
基金supported by the National Key Basic Research Program of China(2013CB127700)the National Natural Science Foundation of China(31101393)
文摘Stripe rust caused by Puccinia striiformis f. sp. tritici is an important wheat disease worldwide that is greatly influenced by environmental conditions. Ultraviolet B(UV-B) radiation is one important environmental factor affecting the occurrence and epidemiology of wheat stripe rust. Investigating UV-B radiation effects on the epidemiology of stripe rust may be conducive to monitoring and predicting this disease. In this study, wheat seedlings were exposed to UV-B radiation during different periods under laboratory conditions and radiation effects on epidemiological components of wheat stripe rust were investigated. Results showed that incubation period was shortened, and the infection efficiency, sporulation quantity and disease index increased when UV-B radiation was performed only pre-inoculation. When the UV-B radiation was performed only postinoculation or both pre-and post-inoculation, the incubation period was prolonged, and the infection efficiency, sporulation quantity and disease index were reduced. When healthy wheat seedlings were inoculated using urediospores collected from wheat leaves irradiated by UV-B only post-inoculation or both pre-and post-inoculation, infection efficiency, sporulation quantity and disease index were also reduced. However, in the latter, the disease incubation period did not differ under varying UV-B radiation intensities compared to that when wheat leaves were not treated with UV-B radiation. Overall, the effects of direct exposure of wheat plants to UV-B radiation with different intensities in different periods on epidemiological components of wheat stripe rust were systematically explored, and the results suggest that the effects of UV-B radiation increased gradually with the increase of UV-B radiation intensity. This information provides a basis for monitoring and predicting this disease as well as for conducting further studies on pathogen virulence variation.
文摘Puccinia striiformis f. sp. tritici (Pst) is one of the pathogenic fungi on wheat, caused stripe rust that is a great threat for wheat production all over the world. Intensive efforts have been made to study genetics of wheat resistance to this disease, but few on avirulence of the pathogen due mainly to the nature of obligate biotrophism and the lack of systems for studying its genetics and molecular manipulations. To overcome these limitations, a natural Pst population comprising 352 isolates representative of a diverse virulence spectrum was genotyped using 97 secreted protein-single nucleotide polymorphism (SP-SNP) markers to identify candidate avirulence genes using association analysis. Among avirulence genes corresponding to 19 resistance genes, significantly associated SP-SNP markers were detected for avirulence genes AvYr1, AvYr2, AvYr6, AvYr7, AvYr8, AvYr44, AvYrExp2, AvYrSP, and AvYrTye. These results indicate that association analysis can be used to identify markers for avirulence genes. This study has laid the foundation for developing more SP-SNPs for mapping avirulence genes using segregating populations that can be generated through sexual reproduction on alternate hosts of the pathogen.
文摘The biotrophic fungus Puccinia striiformis f. sp. tritici is the causal agent of the yellow rust in wheat. Between the years 2010–2013 a new strain of this pathogen(Warrior/Ambition),against which the present cultivated wheat varieties have no resistance, appeared and spread rapidly. It threatens cereal production in most of Europe. The search for sources of resistance to this strain is proposed as the most efficient and safe solution to ensure high grain production. This will be helped by the development of high performance and low cost techniques for field phenotyping. In this study we analyzed vegetation indices in the Red,Green, Blue(RGB) images of crop canopies under field conditions. We evaluated their accuracy in predicting grain yield and assessing disease severity in comparison to other field measurements including the Normalized Difference Vegetation Index(NDVI), leaf chlorophyll content, stomatal conductance, and canopy temperature. We also discuss yield components and agronomic parameters in relation to grain yield and disease severity.RGB-based indices proved to be accurate predictors of grain yield and grain yield losses associated with yellow rust(R2= 0.581 and R2= 0.536, respectively), far surpassing the predictive ability of NDVI(R2= 0.118 and R2= 0.128, respectively). In comparison to potential yield, we found the presence of disease to be correlated with reductions in the number of grains per spike, grains per square meter, kernel weight and harvest index. Grain yield losses in the presence of yellow rust were also greater in later heading varieties. The combination of RGB-based indices and days to heading together explained 70.9% of the variability in grain yield and 62.7% of the yield losses.
文摘Yellow rust of wheat (caused by Puccinia striiformis Westend. f. sp. tritici Eriks.) has been periodically epidemic and severely damaged wheat production in China. The development of resistant cultivars could be an effective way to reduce yield losses of wheat caused by yellow rust. Rust reaction tests and genetic analysis indicated that M08, the synthetic hexaploid wheat derived from hybridization between Triticum durum (2n = 6X = 28; genome AABB) and Aegilops tauschii (2n = 2X = 14; genome DD), showed resistance to current prevailing yellow rust races at seedling stage, which was controlled by a single dominant gene, designated as YrAm. Bulked segregant analysis was used to identify microsatellite markers linked to gene YrAm in an F2 population derived from cross M08 (resistant) × Jinan 17 (susceptible). Three microsatellite marker loci Xgwm77, Xgwm285, and Xgwml31 located on chromosome 3B were mapped to the YrAm locus. Xgwml31 was the closest marker locus and showed a linkage distance of 7.8 cM to the resistance locus. Thus, it is assumed that YrAm for resistance to yellow rust may be derived from Triticum durum and is located on the long arm of chromosome 3B.
基金Supported by the Notice of the Ministry of Agriculture on Approving the First National Modern Agricultural Demonstration Zones in China(Nongjifa[2010]No.22)the Notice of the General Office of the Ministry of Science and Technology on the Construction of the Sixth National Agricultural Science and Technology Parks(National Science and Technology Office for Agriculture[2015]No.9)the Chongqing Research Program of Basic Research and Frontier Technology(cstc2016jcyjA 0316)
文摘The aim of this study is to clarify the application effect of pesticide decrement synergist ' Jijian' on wheal stripe lUSt. Sampling investigation, randomized block design and statistic analysis were carried out to find out the field efficacy of adding ' Jijian' to triadimefon WP and propiconazole EC on controlling wheat stripe rust. The results showed that during the epidemic period of stripe rust, the control effects on the 7^th and the 19^th d reached more than 93% and 100% , respectively, by the application of 15% triadimefon WP of 1 200 g/hm^2 and 25% propiconazole EC of 600 mlhm^2 , respectively for 2 times ; when 15% triadimefon WP of 840 g/hm^2 + ' Jijian' of 225 g/hm^2 or 25 % propiconazole EC of 420 mlhm^2 + ' Jijian' of 225 g/hm^2 were applied ( adding ' Jijian' and reducing the dosage of the 2 pesticides by 30% ) , the control effect on the 7^th d was 89.4% and 91.7% , respectively, while the control effect on the 19a' d was 99.8 - 100% ; when 15% triadimefon WP of 720 - 600 g/hm^2 + ' Jijian' of 225 g/hm^2 or 25% propiconazole EC 360 - 300 mlhm^2 + ' Jijian' of 225 g/hm^2 were applied ( adding ' Jijian' and reducing the dosage of the 2 pesticides by 40% - 50% ) , the control effect on the 7a' day reached more than 78.0% , while the control effect on the 19^th day was 97.7% - 99.8%. There was no significant difference on the control effect at the 7^th d between the treatments using the 2 pesticides alone and the treatments adding ' Jijian' and reducing the dosage of the 2 pesticides by 30%, but all had significant differences from the treatments adding ' Jijian' and reducing the dosage of the 2 pesticides by40% -50%. There was no significant difference on the control effect of the 19^th d among different treatments. Therefore, if the disease is not serious, the application of ' Jijian' can reduce the application amounts of pesticides by 40% -50%, that is, 15% triadimefon WP of 720 -600 g/hm^2 + ' Jijian' of 225 g/hm^2 or 25 % propiconazole EC of 360- 300 ml/hm^2 + ' Jijian' of 225 g/hm^2, which is helpful to reduce the pesticide application amounts and pesticide residue pollution, and save the control costs.
基金National Key Research and Development Program of China(2017YFD0101003)Science and Technology Program of Xinjiang Production and Construction Corps(2016AC027,2019AB021).
文摘Wheat powdery mildew and stripe rust are the major diseases in wheat producing area in Xinjiang.To obtain wheat germplasm resources and varieties resistant to powdery mildew and rust,36 high-generation stable strains of Xinjiang winter wheat were evaluated using the method of natural inducement from 2018 to 2020.A total of 5 strains with high resistance to powdery mildew,4 strains with slow stripe rust and 1 strain with resistance to powdery mildew and adult plant slow stripe rust were obtained.And the parental combination of disease-resistant varieties was analyzed.These studies will provide theoretical basis for the breeding of resistant wheat varieties in Xinjiang.
基金Supported by China Agriculture Research System(CARS-03)International Joint Research Project of Sichuan Province(2014HH0052)+1 种基金Key Research Project of Wheat Breeding in Sichuan ProvinceInnovation Team Project of Wheat in Sichuan Province
文摘Wheat stripe rust,caused by Puccinia striiformis Westend. f. sp. tritici Erikss.( Pst),is one of the most destructive diseases of wheat( Triticum aestivum L.) worldwide. Sichuan province plays an important role in stripe rust epidemic in China. To identify and evaluate wheat stripe rust resistance in Sichuan Province,134 wheat cultivars( lines) were inoculated with seven Pst races at seedling stage and adult stage. The results indicated that the resistance frequencies of wheat cultivars( lines) against seven races CYR31,Su11-7,CYR29,Su11-4,CYR32,CYR33 and V26 were 92. 4%,92. 5%,89. 3%,89. 4%,87. 3%,85. 0% and 82. 8%,respectively. Among 134 materials,76( 56. 0%) performed resistance against all tested races both in seedling and adult stages. The virulence of new pathogenic type V26 of Pst on wheat cultivars( lines) was stronger than the dominant races CYR32 and CYR33. All wheat cultivars( lines) were classified into three types according to analysis of resistance spectrum; 66. 4% of cultivars( lines) showed all-stage resistance,17. 9% were adult-plant resistance,and 15. 7% were susceptible. This indicated that although the overall resistance level of wheat cultivars( lines) in Sichuan Province was very high,the resistance type was simple. Therefore,it is important to identify new resistance genes and enhance resistance gene diversity. Meanwhile,pyramiding breeding of all-stage resistance gene and adult-plant resistance gene could be gradually developed,to achieve durable resistance of wheat cultivars(lines) against stripe rust in Sichuan Province.
文摘Loss of variety resistance to stripe rust (Puccinia striiformis Westend f. sp.tritici) is an important factor causing massive periodical epidemic of rust in wheat production. Creation and development of new races of rust pathogen have led to serious crisis of resistance loss in widely planted varieties. This has quickened the search for new resistance resources. Molecular marker could facilitate the identification of the location of novel genes. A line A-3 with high resistance (immune) to currently epidemic yellow rust races (CY29, 31, 32) was screened out in offspring of Triticum aestivura x Thinopyrum ponticum. Segregation in F2 and BC1 populations indicated that the resistance was controlled by two independent genes: one dominant and one recessive. SSR markers were employed to map the two resistant genes in the F2 and BC1 populations. A marker WMC477-167bp located on 2BS was linked to the dominant gene with genetic distance of 0.4 cM. Another marker WMC364-2os bp located on 7BS was linked to the recessive-resistant gene with genetic distance of 5.8 cM. The two genes identified in this paper might be two novel stripe rust resistant genes, which were temporarily designated as YrTpl and YrTp2, respectively. The tightly linking markers facilitate transfer of the two resistant genes into the new varieties to control epidemic of yellow rust.