scholarly journals The Race-Specific Resistance Gene to Powdery Mildew, MlRE, Has a Residual Effect on Adult Plant Resistance of Winter Wheat Line RE714

1999 ◽  
Vol 89 (7) ◽  
pp. 533-539 ◽  
Author(s):  
N. Chantret ◽  
M. T. Pavoine ◽  
G. Doussinault
Keyword(s):  
Powdery Mildew ◽  
Resistance Genes ◽  
Plant Resistance ◽  
Adult Plant Resistance ◽  
Specific Resistance ◽  
Residual Effect ◽  
Wheat Breeding ◽  
Adult Plant ◽  
Specific Gene ◽  
Dominant Type

Race-specific resistance genes to powdery mildew have been extensively used in wheat breeding programs, but the complete resistance they provide breaks down when confronted by pathogen isolates with matching virulence. However, when overcome, some race-specific genes have a residual action leading to a reduction of the symptoms. Our objective was to determine if the resistance genes MlRE and Pm4b have a residual effect on adult plant resistance (APR) and on vernalized seedling plant resistance (VPR) in the line RE714. Individuals from two populations (double haploid [DH] and F3 families) were genotyped for the race-specific genes MlRE and Pm4b and assessed for their resistance under field conditions at the adult plant stage (in 1996 and 1997 for the DH lines and in 1997 for the F3 families). Vernalized seedlings of the DH population were tested with four powdery mildew isolates. Only the MlRE gene had a significant effect (dominant type) on APR. Neither MlRE nor Pm4b had a significant effect on VPR. The dominant residual effect of the defeated race-specific gene MlRE was a component of APR in the line RE714.

scholarly journals Seedling and Adult Plant Resistance to Powdery Mildew in Chinese Bread Wheat Cultivars and Lines

Plant Disease ◽  
2005 ◽  
Vol 89 (5) ◽  
pp. 457-463 ◽  
Author(s):  
Z. L. Wang ◽  
L. H. Li ◽  
Z. H. He ◽  
X. Y. Duan ◽  
Y. L. Zhou ◽  
...  
Keyword(s):  
Powdery Mildew ◽  
Bread Wheat ◽  
Resistance Genes ◽  
Plant Resistance ◽  
Adult Plant Resistance ◽  
The United States ◽  
Adult Plant ◽  
Wheat Cultivars ◽  
Seedling Resistance ◽  
Progress Curve

Powdery mildew, caused by Blumeria graminis f. sp. tritici, is a widespread wheat disease in China. Identification of race-specific genes and adult plant resistance (APR) is of major importance in breeding for an efficient genetic control strategy. The objectives of this study were to (i) identify genes that confer seedling resistance to powdery mildew in Chinese bread wheat cultivars and introductions used by breeding programs in China and (ii) evaluate their APR in the field. The results showed that (i) 98 of 192 tested wheat cultivars and lines appear to have one or more resistance genes to powdery mildew; (ii) Pm8 and Pm4b are the most common resistance genes in Chinese wheat cultivars, whereas Pm8 and Pm3d are present most frequently in wheat cultivars introduced from CIMMYT, the United States, and European countries; (iii) genotypes carrying Pm1, Pm3e, Pm5, and Pm7 were susceptible, whereas those carrying Pm12, Pm16, and Pm20 were highly resistant to almost all isolates of B. graminis f. sp. tritici tested; and (iv) 22 genotypes expressed APR. Our data showed that the area under the disease progress curve, maximum disease severity on the penultimate leaf, and the disease index are good indicators of the degree of APR in the field. It may be a good choice to combine major resistance genes and APR genes in wheat breeding to obtain effective resistance to powdery mildew.

scholarly journals Genetic Analysis of Adult Plant Resistance to Yellow Rust and Leaf Rust in Common Spring Wheat Quaiu 3

Plant Disease ◽  
2013 ◽  
Vol 97 (6) ◽  
pp. 728-736 ◽  
Author(s):  
B. R. Basnet ◽  
R. P. Singh ◽  
S. A. Herrera-Foessel ◽  
A. M. H. Ibrahim ◽  
J. Huerta-Espino ◽  
...  
Keyword(s):  
Spring Wheat ◽  
Resistance Genes ◽  
Plant Resistance ◽  
Adult Plant Resistance ◽  
Molecular Mapping ◽  
Puccinia Striiformis ◽  
Wheat Breeding ◽  
Adult Plant ◽  
Breeding Programs ◽  
Qualitative Approaches

Identifying and utilizing rust resistance genes in wheat has been hampered by the continuous and rapid emergence of new pathogen races. A major focus of many wheat breeding programs is achieving durable adult plant resistance (APR) to yellow (stripe) rust (YR) and leaf (brown) rust (LR), caused by Puccinia striiformis and P. triticina, respectively. This study aimed to determine the genetic basis of resistance to YR and LR in the common spring wheat ‘Quaiu 3’. To that end, we evaluated 198 F5 recombinant inbred lines (RILs), derived from a cross of susceptible ‘Avocet-YrA’ with Quaiu 3, for APR to LR and YR in artificially inoculated field trials conducted in Mexico during the 2009 and 2010 growing seasons. High narrow-sense heritability (h2) estimates, ranging between 0.91 and 0.95, were obtained for both LR and YR disease severities for both years. The quantitative and qualitative approaches used to estimate gene numbers showed that, in addition to known resistance genes, there are at least two to three APR genes associated with LR and YR resistance in the RIL population. The moderately effective race-specific resistance gene Lr42 and the pleiotropic slow-rusting APR gene Lr46/Yr29 were found to interact with additional unidentified APR genes. The unidentified APR genes should be of particular interest for further characterization through molecular mapping, and for utilization by wheat breeding programs.

scholarly journals Adult Plant Resistance in Maize to Northern Leaf Spot Is a Feature of Partial Loss-of-function Alleles ofHm1

2018 ◽  
Author(s):  
Sandeep R. Marla ◽  
Kevin Chu ◽  
Satya Chintamanani ◽  
Dilbag Multani ◽  
Antje Klempien ◽  
...  
Keyword(s):  
Disease Resistance ◽  
Resistance Genes ◽  
Plant Resistance ◽  
Leaf Spot ◽  
Adult Plant Resistance ◽  
Plant Diseases ◽  
Adult Plant ◽  
Hc Toxin ◽  
Differential Transcription

ABSTRACTAdult plant resistance (APR) is an enigmatic phenomenon in which resistance genes are ineffective in protecting seedlings from disease but confer robust resistance at maturity. Maize has multiple cases in which genes confer APR to northern leaf spot, a lethal disease caused byCochliobolus carbonumrace 1 (CCR1). The first identified case of APR in maize is encoded by a hypomorphic allele,Hm1A, at thehm1locus. In contrast, wild type alleles ofhm1provide complete protection at all developmental stages and in every part of the maize plant.Hm1encodes an NADPH-dependent reductase, which inactivates HC-toxin, a key virulence effector of CCR1. Cloning and characterization ofHm1Aruled out differential transcription or translation for its APR phenotype and identified an amino acid substitution that reduced HC-toxin reductase (HCTR) activity. The possibility of a causal relationship between the weak nature ofHm1Aand its APR phenotype was confirmed by the generation of two new APR alleles ofHm1by mutagenesis. The HCTRs encoded by these new APR alleles had undergone relatively conservative missense changes that partially reduced their enzymatic activity similar to HM1A. No difference in accumulation of HCTR was observed between adult and juvenile plants, suggesting that the susceptibility of seedlings derives from a greater need for HCTR activity, not reduced accumulation of the gene product. Conditions and treatments that altered the photosynthetic output of the host had a dramatic effect on resistance imparted by the APR alleles, demonstrating a link between the energetic or metabolic status of the host and disease resistance affected by HC-toxin catabolism by the APR alleles of HCTR.AUTHOR SUMMARYAdult plant resistance (APR) is a phenomenon in which disease resistance genes are able to confer resistance at the adult stages of the plant but somehow fail to do so at the seedling stages. Despite the widespread occurrence of APR in various plant diseases, the mechanism underlying this trait remains obscure. It is not due to the differential transcription of these genes, and here we show that it is also not due to the differential translation or activity of the APR alleles of the maizehm1gene at different stages of development. Using a combination of molecular genetics, biochemistry and physiology, we present multiple lines of evidence that demonstrate that APR is a feature or symptom of weak forms of resistance. While the mature parts of the plant are metabolically robust enough to manifest resistance, seedling tissues are not, leaving them vulnerable to disease. Growth conditions that compromise the photosynthetic output of the plant further deteriorate the ability of the seedlings to protect themselves from pathogens.One sentence summaryCharacterization of adult plant resistance in the maize-CCR1 pathosystem reveals a causal link between weak resistance and APR.

scholarly journals Quantitative Trait Loci Mapping for Adult-Plant Resistance to Powdery Mildew in Bread Wheat

2006 ◽  
Vol 96 (7) ◽  
pp. 784-789 ◽  
Author(s):  
S. S. Liang ◽  
K. Suenaga ◽  
Z. H. He ◽  
Z. L. Wang ◽  
H. Y. Liu ◽  
...  
Keyword(s):  
Quantitative Trait Loci ◽  
Powdery Mildew ◽  
Plant Resistance ◽  
Quantitative Trait ◽  
Powdery Mildew Resistance ◽  
Adult Plant Resistance ◽  
Adult Plant ◽  
Phenotypic Variance ◽  
Mildew Resistance ◽  
Trait Loci

Powdery mildew, caused by Blumeria graminis f. sp. tritici, is a major disease to wheat (Triticum aestivum) worldwide. Use of adult-plant resistance (APR) is an effective method to develop wheat cultivars with durable resistance to powdery mildew. In the present study, 432 molecular markers were used to map quantitative trait loci (QTL) for APR to powdery mildew in a doubled haploid (DH) population with 107 lines derived from the cross Fukuho-komugi × Oligoculm. Field trials were conducted in Beijing and Anyang, China during 2003-2004 and 2004-2005 cropping seasons, respectively. The DH lines were planted in a randomized complete block design with three replicates. Artificial inoculation was carried out in Beijing with highly virulent isolate E20 of B. graminis f. sp. tritici and the powdery mildew severity on penultimate leaf was evaluated four times, and the maximum disease severity (MDS) on penultimate leaf was investigated in Anyang under natural inoculation in May 2004 and 2005. The heritability of resistance to powdery mildew for MDS in 2 years and two locations ranged from 0.82 to 0.93, while the heritability for area under the disease progress curve was between 0.84 and 0.91. With the method of composite interval mapping, four QTL for APR to powdery mildew were detected on chromosomes 1AS, 2BL, 4BL, and 7DS, explaining 5.7 to 26.6% of the phenotypic variance. Three QTL on chromosomes 1AS, 2BL, and 7DS were derived from the female, Fukuho-komugi, while the one on chromosome 4BL was from the male, Oligoculm. The QTL on chromosome 1AS showed high genetic effect on powdery mildew resistance, accounting for 19.5 to 26.6% of phenotypic variance across two environments. The QTL on 7DS associated with the locus Lr34/Yr18, flanked by microsatellite Xgwm295.1 and Ltn (leaf tip necrosis). These results will benefit for improving powdery mildew resistance in wheat breeding programs.

Overview and Application of QTL for Adult Plant Resistance to Leaf Rust and Powdery Mildew in Wheat

Crop Science ◽  
2014 ◽  
Vol 54 (5) ◽  
pp. 1907-1925 ◽  
Author(s):  
Zaifeng Li ◽  
Caixia Lan ◽  
Zhonghu He ◽  
Ravi P. Singh ◽  
Garry M. Rosewarne ◽  
...  
Keyword(s):  
Powdery Mildew ◽  
Leaf Rust ◽  
Plant Resistance ◽  
Adult Plant Resistance ◽  
Adult Plant
Sign in / Sign up

Export Citation Format

Share Document