scholarly journals AN ANALYSIS OF THE CHRACTERIZATION OF ENVIRONMENTAL CONDITIONS CONDUCIVE FOR LEAF RUST RESISTANCE AND GENETIC DIVERSITY ON WHEAT CROSSES BASED UPON PHYSIOMORPHIC TRAITS

2021 ◽  
Vol 33 (1) ◽  
Author(s):  
Yasir Ali
Keyword(s):  
Genetic Diversity ◽  
Leaf Rust ◽  
Environmental Conditions ◽  
Rust Resistance ◽  
Leaf Rust Resistance

The transfer of leaf rust resistance from Triticum turgidum ssp. dicoccoides to hexaploid wheat

1994 ◽  
Vol 74 (4) ◽  
pp. 671-673 ◽  
Author(s):  
P. L. Dyck
Keyword(s):  
Genetic Diversity ◽  
Genetic Analysis ◽  
Leaf Rust ◽  
Resistance Gene ◽  
Hexaploid Wheat ◽  
Rust Resistance ◽  
Triticum Turgidum ◽  
Leaf Rust Resistance ◽  
Rust Resistance Gene ◽  
Leaf Rust Resistance Gene

Accession 8404 of Triticum turgidum ssp. dicoccoides was shown to have excellent resistance to leaf rust. Genetic analysis of the F3 of 8404 and RL6089, a leaf rust susceptible durum, indicated that 8404 had three genes for leaf rust resistance. Two of these genes were transferred to hexaploid wheat (Thatcher) by a series of backcrosses. One of the genes transferred was the same as Lr33 (RL6057). The second gene, which gives a fleck reaction to avirulent P. recondita races, appears to be fully incorporated into the hexaploid where it segregated to fit a one-gene ratio. Backcross lines with this gene give excellent resistance to leaf rust, although race MBG is virulent to this gene. This may be a previously unidentified leaf rust resistance gene and should increase the genetic diversity available for wheat breeders. Key words:Triticum aestivum, wheat, Triticum turgidum ssp. dicoccoides, leaf rust resistance

Quantification of Leaf Rust Resistance Source in Wheat Germplasm in Relation to Epidemiological Factors

2020 ◽  
Author(s):  
Yasir Ali ◽  
Hafiz Muhammad Aatif ◽  
Muhammad Aslam Khan ◽  
Muhammad Bashair ◽  
Muhammad Zeeshan Mansha ◽  
...  
Keyword(s):  
Leaf Rust ◽  
Environmental Conditions ◽  
Rust Resistance ◽  
Agricultural Research ◽  
Great Influence ◽  
Leaf Rust Resistance ◽  
Maximum Temperature ◽  
Lr Genes ◽  
Epidemiological Factors ◽  
Research Institute

A comprehensive germplasm screening study of 855 wheat advanced lines was conducted at Wheat Research Institute, Ayub Agricultural Research Institute Faisalabad to identify new sources of leaf rust resistance during crop seasons 2015-2017. In primary evaluation, 112 advanced lines were selected having high phenotypic uniformity for further testing at wheat research Institute Faisalabad, a hotspot for leaf rust. The second round of evaluation exhibited 54 lines having durable type resistance against leaf rust. Avirulence to virulence formula showed that 7 Lr genes remained most effective at all four locations. Epidemiological factors indicated great influence on the progress of leaf rust disease development. Maximum lines showed statistically significant correlation with all environmental conditions. A positive linear relationship was observed between minimum and maximum temperature, relative humidity, rainfall and wind speed. It was concluded that resistant wheat advanced lines and Lr genes identified under natural environmental conditions can be an excellent source to be employed for breeding resistance into the background of high yielding wheat cultivars through molecular or conventional breeding technique, and are expected to contribute toward food security at national and global levels.

Lr80: A new and widely effective source of leaf rust resistance of wheat for enhancing diversity of resistance among modern cultivars

2021 ◽  
Author(s):  
Subodh Kumar ◽  
Subhash C. Bhardwaj ◽  
Om P. Gangwar ◽  
Akanksha Sharma ◽  
Naeela Qureshi ◽  
...  
Keyword(s):  
Leaf Rust ◽  
Rust Resistance ◽  
Leaf Rust Resistance ◽  
Effective Source

scholarly journals Map-Based Cloning of Leaf Rust Resistance Gene Lr21 From the Large and Polyploid Genome of Bread Wheat

Genetics ◽  
2003 ◽  
Vol 164 (2) ◽  
pp. 655-664 ◽  
Author(s):  
Li Huang ◽  
Steven A Brooks ◽  
Wanlong Li ◽  
John P Fellers ◽  
Harold N Trick ◽  
...  
Keyword(s):  
Amino Acid ◽  
Leaf Rust ◽  
Resistance Gene ◽  
Bread Wheat ◽  
Rust Resistance ◽  
Agronomic Traits ◽  
Leaf Rust Resistance ◽  
Triticum Aestivum L ◽  
Rust Resistance Gene ◽  
Leaf Rust Resistance Gene

Abstract We report the map-based cloning of the leaf rust resistance gene Lr21, previously mapped to a generich region at the distal end of chromosome arm 1DS of bread wheat (Triticum aestivum L.). Molecular cloning of Lr21 was facilitated by diploid/polyploid shuttle mapping strategy. Cloning of Lr21 was confirmed by genetic transformation and by a stably inherited resistance phenotype in transgenic plants. Lr21 spans 4318 bp and encodes a 1080-amino-acid protein containing a conserved nucleotide-binding site (NBS) domain, 13 imperfect leucine-rich repeats (LRRs), and a unique 151-amino-acid sequence missing from known NBS-LRR proteins at the N terminus. Fine-structure genetic analysis at the Lr21 locus detected a noncrossover (recombination without exchange of flanking markers) within a 1415-bp region resulting from either a gene conversion tract of at least 191 bp or a double crossover. The successful map-based cloning approach as demonstrated here now opens the door for cloning of many crop-specific agronomic traits located in the gene-rich regions of bread wheat.

scholarly journals Identification of leaf rust resistance genes Lr34 and Lr46 in common wheat (Triticum aestivum L. ssp. aestivum) lines of different origin using multiplex PCR

2021 ◽  
Vol 16 (1) ◽  
pp. 172-183
Author(s):  
Agnieszka Tomkowiak ◽  
Roksana Skowrońska ◽  
Michał Kwiatek ◽  
Julia Spychała ◽  
Dorota Weigt ◽  
...  
Keyword(s):  
Multiplex Pcr ◽  
Leaf Rust ◽  
Common Wheat ◽  
Fungal Pathogens ◽  
Rust Resistance ◽  
Leaf Rust Resistance ◽  
Field Conditions ◽  
Pcr Marker ◽  
Specific Sequence ◽  
Cereal Species

Abstract Leaf rust caused by the fungus Puccinia recondita f. sp. tritici is one of the most dangerous diseases of common wheat. Infections caused by fungal pathogens reduce the quantity and quality of yields of many cereal species. The most effective method to limit plant infection is to use cultivars that show rust resistance. Genetically conditioned horizontal-type resistance (racial-nonspecific) is a desirable trait because it is characterized by more stable expression compared to major (R) genes that induce racially specific resistance, often overcome by pathogens. Horizontal resistance is conditioned by the presence of slow rust genes, which include genes Lr34 and Lr46. This study aimed to identify markers linked to both genes in 64 common wheat lines and to develop multiplex PCR reaction conditions that were applied to identify both genes simultaneously. The degree of infestation of the analyzed lines was also assessed in field conditions during the growing season of 2017 and 2018. Simple sequence repeat anchored-polymerase chain reaction (SSR-PCR) marker csLV was identified during analysis in line PHR 4947. The presence of a specific sequence has also been confirmed in multiplex PCR analyses. In addition to gene Lr34, gene Lr46 was identified in this genotype. Lines PHR 4947 and PHR 4819 were characterized by the highest leaf rust resistance in field conditions. During STS-PCR analyses, the marker wmc44 of gene Lr46 was identified in most of the analyzed lines. This marker was not present in the following genotypes: PHR 4670, PHR 4800, PHR 4859, PHR 4907, PHR 4922, PHR 4949, PHR 4957, PHR 4995, and PHR 4997. The presence of a specific sequence has also been confirmed in multiplex PCR analyses. Genotypes carrying the markers of the analyzed gene showed good resistance to leaf rust in field conditions in both 2017 and 2018. Research has demonstrated that marker assisted selection (MAS) and multiplex PCR techniques are excellent tools for selecting genotypes resistant to leaf rust.

Sign in / Sign up

Export Citation Format

Share Document