Phenotypic and genotypic variability for durable resistance to yellow rust (Puccinia striiformisf. sp.tritici) in Pakistan wheat cultivars

The use of cytoplasmatic male-sterility in maize seed production contributes to increase economical efficiency and to obtain great genetical seeds. Through this theme one has followed the realization of a comparative study between some hybrids obtained to Turda on C and T cytoplasm their homologues, developed with normal and through the castration of the maternal parents. The researches aimed mainly the phenotypic and genotypic variability of the hybrids, the degree of male-sterility and the capacity of production, in phytotechnic conditions in different densities.

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Evaluation of resistance to powdery mildew and identification of resistance genes in wheat cultivars

10.21203/rs.3.rs-19487/v1 ◽

2020 ◽

Author(s):

Xian Xin Wu ◽

Yue Gao ◽

Qiang Bian ◽

Qian Sun ◽

Xin Yu Ni ◽

...

Keyword(s):

Powdery Mildew ◽

Resistance Genes ◽

Large Scale ◽

Durable Resistance ◽

Cost Effective ◽

Blumeria Graminis ◽

Wheat Cultivars ◽

Seedling Resistance ◽

Initial Inoculum ◽

Wheat Powdery Mildew

Abstract Background: Wheat powdery mildew, caused by the biotrophic fungus Blumeria graminis f. sp. tritici ( Bgt ), is a serious disease of wheat worldwide that can cause significant yield losses. Growing resistant cultivars is the most cost-effective and eco-soundly strategy to manage the disease. Therefore, a high breeding priority is to identify genes that can be readily used either singly or in combination for effective resistance to powdery mildew and alos in combination with genes for resistance to other diseases. Yunnan Province, with complex and diverse ecological environments and climates, is one of the main wheat growing regions in China. This region provides initial inoculum for starting epidemics of wheat powdery mildew in the region and other regions and thus, plays a key role in the regional and large-scale epidemics of the disease throughout China. The objectives of this study were to evaluate seedling resistance of 69 main wheat cultivars to powdery mildew and to determine the presence of resistance genes Pm3 , Pm8 , Pm13 , Pm16 , and Pm21 in these cultivars using gene specific DNA markers. Results: Evaluation of 69 wheat cultivars with six Bgt isolates showed that only four cultivars were resistant to all tested isolates, indicating that the overall level of powdery mildew resistance of Yunnan wheat cultivars is inadequate. The molecular marker results showed that 27 cultivars likely have at least one of these genes. Six cultivars were found likely to have Pm3 , 18 likely to have Pm8 , 5 likely to have Pm16 , and 3 likely to have Pm21 . No cultivar was found to carry Pm13 . Conclusion: The information on the presence of the Pm resistance genes in Yunnan wheat cultivars can be used in future wheat disease breeding programs. In particular, cultivars carrying Pm21 , which is effective against all Bgt races in China, should be pyramided with other effective genes to developing new cultivars with durable resistance to powdery mildew. Keywords: Blumeria graminis f. sp. tritici , Pm gene, molecular markers, wheat

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A Project to Transfer Durable Resistance to Stripe (Yellow) Rust from European to Indian Bread Wheats

Durability of Disease Resistance - Current Plant Science and Biotechnology in Agriculture ◽

10.1007/978-94-011-2004-3_56 ◽

1993 ◽

pp. 328-328 ◽

Cited By ~ 1

Author(s):

R. Johnson

Keyword(s):

Yellow Rust ◽

Durable Resistance

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Identification of QTLs/Defense Genes Effective at Seedling Stage Against Prevailing Races of Wheat Stripe Rust in India

Frontiers in Genetics ◽

10.3389/fgene.2020.572975 ◽

2020 ◽

Vol 11 ◽

Author(s):

Anjan Kumar Pradhan ◽

Sundeep Kumar ◽

Amit Kumar Singh ◽

Neeraj Budhlakoti ◽

Dwijesh C. Mishra ◽

...

Keyword(s):

Stripe Rust ◽

Genome Wide Association Study ◽

Durable Resistance ◽

Winter Season ◽

Seedling Stage ◽

Wheat Cultivars ◽

Sources Of Resistance ◽

Genome Wide ◽

A Genome ◽

Genomic Locations

Resistance in modern wheat cultivars for stripe rust is not long lasting due to the narrow genetic base and periodical evolution of new pathogenic races. Though nearly 83 Yr genes conferring resistance to stripe rust have been cataloged so far, few of them have been mapped and utilized in breeding programs. Characterization of wheat germplasm for novel sources of resistance and their incorporation into elite cultivars is required to achieve durable resistance and thus to minimize the yield losses. Here, a genome-wide association study (GWAS) was performed on a set of 391 germplasm lines with the aim to identify quantitative trait loci (QTL) using 35K Axiom® array. Phenotypic evaluation disease severity against four stripe rust pathotypes, i.e., 46S119, 110S119, 238S119, and 47S103 (T) at the seedling stage in a greenhouse providing optimal conditions was carried out consecutively for 2 years (2018 and 2019 winter season). We identified, a total of 17 promising QTl which passed FDR criteria. Moreover these 17 QTL identified in the current study were mapped at different genomic locations i.e. 1B, 2A, 2B, 2D, 3A, 3B, 3D, 4B, 5B and 6B. These 17 QTLs identified in the present study might play a key role in marker-assisted breeding for developing stripe rust resistant wheat cultivars.

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Possible involvement of phytoalexins in durable resistance of winter wheat to yellow rust

Transactions of the British Mycological Society ◽

10.1016/s0007-1536(81)80154-4 ◽

1981 ◽

Vol 76 (2) ◽

pp. 323-325 ◽

Cited By ~ 4

Author(s):

D.W. Cartwright ◽

G.E. Russell

Keyword(s):

Winter Wheat ◽

Yellow Rust ◽

Durable Resistance

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High Relative Parasitic Fitness of G22 Derivatives is Associated with the Epidemic Potential of Wheat Stripe Rust in China

Plant Disease ◽

10.1094/pdis-04-17-0511-sr ◽

2018 ◽

Vol 102 (3) ◽

pp. 483-487 ◽

Cited By ~ 9

Author(s):

Bing Bing Bai ◽

Tai Guo Liu ◽

Bo Liu ◽

Li Gao ◽

Wan Quan Chen

Keyword(s):

Latent Period ◽

Stripe Rust ◽

Large Scale ◽

Puccinia Striiformis ◽

Germination Rate ◽

Durable Resistance ◽

Wheat Cultivars ◽

Wheat Stripe Rust ◽

Expansion Speed ◽

Parasitic Fitness

In total, 13 commercial wheat cultivars around China and four races of Puccinia striiformis f. sp. tritici (namely, CYR32, CYR33, G22-9, and G22-14) were employed for a test of relative parasitic fitness (RPF) using the drop method. The RPF values were measured, including the urediniospore germination rate, the latent period, the uredinial length, the uredinial density, the infection area, the sporulation intensity, the lesion expansion speed, and the sporulation period. The results indicated that the parameters of relative parasitic fitness of the four P. striiformis f. sp. tritici races on the 13 wheat cultivars were significantly different (P = 0.00) in sporulation intensity, lesion expansion speed, uredinial length, sporulation period, uredinial density, and latent period. The urediniospore germination rates of the four P. striiformis f. sp. tritici races for the test were significantly different (P = 0.00), whereas no correlation with the different cultivars was observed (P = 1.00). The infection areas of the tested races on the different cultivars were significantly different (P = 0.00) but there were no obvious manifestations among the various races (P = 0.20). Principal component analysis (PCA) showed that the sporulation intensity represented sporulation capacity and scalability, the latent period indicated infection ability, and the urediniospore germination rate represented urediniospore vigor, all of which fully contributed to the RPF in the interaction of the four races and 13 wheat cultivars, which was calculated by the following formula: RPF = (sporulation intensity × urediniospore germination rate)/latent period. The sporulation and infection of G22-9 on the 13 large-scale cultivated cultivars were the highest, and the RPF of G22-9 was higher than that of the predominant races, CYR32 and CYR33. This result suggested that G22-9 could become a new predominant race and potentially cause epidemics of wheat stripe rust in China. To prevent potential epidemics, susceptible wheat cultivars should be withdrawn from production and breeding programs should reduce the use of Yr10 and Yr26 and use other more effective resistance genes in combination with nonrace-specific resistance for developing wheat cultivars with durable resistance to stripe rust.

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A rapid method for measuring production of yellow rust spores on single seedlings to assess differential interactions of wheat cultivars with Puccinia striiformis

Annals of Applied Biology ◽

10.1111/j.1744-7348.1974.tb01401.x ◽

1974 ◽

Vol 77 (3) ◽

pp. 251-258 ◽

Cited By ~ 20

Author(s):

R. JOHNSON ◽

D. E. BOWYER

Keyword(s):

Rapid Method ◽

Puccinia Striiformis ◽

Yellow Rust ◽

Wheat Cultivars

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Evaluation of resistance to powdery mildew and identification of resistance genes in wheat cultivars

PeerJ ◽

10.7717/peerj.10425 ◽

2021 ◽

Vol 9 ◽

pp. e10425

Author(s):

Xianxin Wu ◽

Qiang Bian ◽

Yue Gao ◽

Xinyu Ni ◽

Yanqiu Sun ◽

...

Keyword(s):

Powdery Mildew ◽

Resistance Genes ◽

Large Scale ◽

Durable Resistance ◽

Cost Effective ◽

Wheat Cultivars ◽

Seedling Resistance ◽

Initial Inoculum ◽

Wheat Powdery Mildew ◽

Serious Disease

Wheat powdery mildew, caused by the biotrophic fungus Blumeria graminis f. sp. tritici (Bgt), is a serious disease of wheat worldwide that can cause significant yield losses. Growing resistant cultivars is the most cost-effective and eco-soundly strategy to manage the disease. Therefore, a high breeding priority is to identify genes that can be readily used either singly or in combination for effective resistance to powdery mildew and also in combination with genes for resistance to other diseases. Yunnan Province, with complex and diverse ecological environments and climates, is one of the main wheat growing regions in China. This region provides initial inoculum for starting epidemics of wheat powdery mildew in the region and other regions and thus, plays a key role in the regional and large-scale epidemics of the disease throughout China. The objectives of this study were to evaluate seedling resistance of 69 main wheat cultivars to powdery mildew and to determine the presence of resistance genes Pm3, Pm8, Pm13, Pm16, and Pm21in these cultivars using gene specific DNA markers. Evaluation of 69 wheat cultivars with six Bgt isolates showed that only four cultivars were resistant to all tested isolates, indicating that the overall level of powdery mildew resistance of Yunnan wheat cultivars is inadequate. The molecular marker results showed that 27 cultivars likely have at least one of these genes. Six cultivars were found likely to have Pm3,18 likely to have Pm8,5 likely to have Pm16,and 3 likely to have Pm21. No cultivar was found to carry Pm13. The information on the presence of the Pmresistance genes in Yunnan wheat cultivars can be used in future wheat disease breeding programs. In particular, cultivars carrying Pm21, which is effective against all Bgtraces in China, should be pyramided with other effective genes to developing new cultivars with durable resistance to powdery mildew.

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