Article

Global status of wheat leaf rust caused by Puccinia triticina

Euphytica (Impact Factor: 1.64). 01/2011; 179(1):143-160. DOI: 10.1007/s10681-011-0361-x

ABSTRACT Leaf rust caused by Puccinia triticina is the most common and widely distributed of the three wheat rusts. Losses from leaf rust are usually less damaging than
those from stem rust and stripe rust, but leaf rust causes greater annual losses due to its more frequent and widespread occurrence.
Yield losses from leaf rust are mostly due to reductions in kernel weight. Many laboratories worldwide conduct leaf rust surveys
and virulence analyses. Most currently important races (pathotypes) have either evolved through mutations in existing populations
or migrated from other, often unknown, areas. Several leaf rust resistance genes are cataloged, and high levels of slow rusting
adult plant resistance are available in high yielding CIMMYT wheats. This paper summarizes the importance of leaf rust in
the main wheat production areas as reflected by yield losses, the complexity of virulence variation in pathogen populations,
the role cultivars with race-specific resistance play in pathogen evolution, and the control measures currently practiced
in various regions of the world.

Keywords
Triticum aestivum

Triticum turgidum
–Resistance–Races

1 Bookmark
 · 
323 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Puccinia horiana is the causal agent of chrysanthemum white rust or Japanese rust. This microcyclic autoecious rust has a quarantine status and can cause major damage in the commercial production of Chrysanthemum x morifolium. Given the international and often trans-continental production of planting material and cut flowers of chrysanthemum and the decreasing availability of registered fungicides in specific regions, breeding for resistance against P. horiana will gain importance and will need to involve the appropriate resistance genes for the pathotypes that may be present. As pathotypes have not been well characterized in this system, the main objective was to build an international collection of isolates and screen these on a large collection of cultivars to identify different pathotypes. Using a robust and high throughput bioassay, we tested 36 selected cultivars with 22 individual single-pustule isolates of P. horiana. The isolates originated from three different continents over 4 different collection years and included some isolates from cultivars previously reported as resistant. In most cases the bioassays resulted in a clear scoring of interaction phenotypes as susceptible or resistant, while in several cases consistent intermediate phenotypes were found, often on specific cultivars. Twenty-four of the cultivars gave a differential interaction phenotype profile. All isolates produced a unique profile, infecting a minimum of 4 and a maximum of 19 differential cultivars. Based on the Person analysis of these profiles, this pathosystem contains at least seven resistance genes (and seven avirulence genes), demonstrating the highly complex race structure in this pathosystem. KeywordsAvirulence–Bioassay– Chrysanthemum x morifolium –Elicitors–Resistance–Rust
    European Journal of Plant Pathology 01/2011; 130(3):325-338. · 1.71 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Since weather has a major influence on the occurrence and development of crop diseases, valuable insight toward future agricultural planning emerges with assessment tools to evaluate fungal disease pressure and crop regional suitability under projected future climatic conditions. The aim of this study was to develop two climatic indicators, the average infection efficiency (AIE) and the number of infection days (NID), to quantify the potential effects of weather on the intensity and occurrence of pathogen infection. First, a simple and continuous infection function accounting for daily temperature and leaf wetness duration variations was implemented. The function was then parameterized from published data sets for five major contrasting fungal diseases affecting crops in Northern France: phoma of oilseed rape, late blight of potato, downy mildew of grape, leaf rust of wheat and net blotch of barley. Finally, AIE and NID were calculated for the recent past (1970–2000) and the future A1B climate scenario (2070–2100). An overall decrease in the risk of infection was shown for potato late blight and downy mildew of grapevine for all months during the period when the host plant is susceptible to infection. There were greater differences for the other three diseases, depending on the balance between warmer temperatures and lower humidity. The future climate would result in a later onset of disease and higher infection pressure in late autumn. In spring, for brown rust of wheat and net blotch of barley, the climatic risk for infection is expected to occur earlier but would result in lower infection pressure in May. These findings highlighted the need to use an infra-annual (monthly or seasonally) scale to achieve a relevant analysis of the impact of climate change on the infection risk. The described indicators can easily be adapted to other pathogens and may be useful for agricultural planning at the regional scale and in the medium term, when decision support tools are required to anticipate future trends and the associated risks of crop diseases.
    Agriculture Ecosystems & Environment 01/2014; 197:147–158. · 2.86 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Leaf rust caused by Puccinia triticina is an economically-important disease in wheat worldwide. A combination of different types of resistance genes may significantly enhance rust resistance under rust-favorable conditions. To investigate the interactions between the rust resistance gene Lr34 and the lesion mimic gene lm on 1BL in Ning 7840, a segregating F8-10 population of 180 recombinant inbred lines was developed from Ning 7840/Chokwang and evaluated for both lesion mimic expression and leaf rust response at the adult plant stage in a greenhouse. A major quantitative trait locus (QTL), derived from Sumai 3, was co-localized with Lr34 on chromosome 7D and explained 41.5% of phenotypic variations for rust severity and 22.1% for leaf tip necrosis (LTN). The presence of Lr34 was confirmed by Lr34-specific markers cssfr1 and cssfr2 in Ning 7840 and Sumai 3. Unlike Lr34, lm conditioned a spontaneous lesion mimic phenotype and had a significant effect on reducing uredinial size, and a smaller effect on severity. Additive effects were observed between lm and Lr34 for severity and LTN, and an epistatic effect was observed for infection type. Single marker analysis also identified several other QTL with minor effects on severity, infection type, or LTN.
    Chinese Science Bulletin 57(17). · 1.37 Impact Factor

Full-text

View
101 Downloads
Available from
May 20, 2014