Decreased capacity of take‐all fungus to oxidize manganous ions is associated with take‐all decline

Rengel, Zed

doi:10.1080/01904169709365266

Cited by 11 publications

(3 citation statements)

References 9 publications

(10 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, Mn deficiency in wheat was noted to increase its susceptibility to G. graminis (Brennan, 1992; Graham and Rovira, 1984) and Mn fertilization can decrease take‐all disease (Wilhelm et al, 1988) Wheat roots infected with G. graminis were shown to cause a strong oxidation of Mn 2+ to Mn 4+ , which precipitates and was observed in the interior of roots (Schulze et al, 1995). Rengel (1997) noted that the lower the capacity of an isolate of this fungi to oxidize Mn 2+ into plant‐unavailable Mn 3+ and/or Mn 4+ , the lower its virulence to cause take‐all disease.…”

Section: Resultsmentioning

confidence: 99%

Tillage Intensity, Mycorrhizal and Nonmycorrhizal Fungi, and Nutrient Concentrations in Maize, Wheat, and Canola

Mozafar

Anken²,

Ruh

et al. 2000

Agronomy Journal

View full text Add to dashboard Cite

Reduced tillage can change numerous physico‐chemical properties of soil and the activity of various microorganisms including mycorrhizal and pathogenic soil fungi, and thus influence nutrient uptake by plant roots. We studied the colonization of roots by mycorrhizal and nonmycorrhizal fungi and nutrient concentrations in plant tops grown during a 3‐yr rotation of maize (Zea mays L.), winter wheat (Triticum aestivum L.), and canola (Brassica napus L.) in two sites in Switzerland where fields have been under three tillage treatments (conventional, CT; chisel plow, CP; and no‐tillage, NT) since 1987. Maize roots were colonized to a greater extent by mycorrhizal fungi with NT than with CP or CT treatments. Wheat roots were equally and weakly colonized by mycorrhizal fungi in all treatments but were relatively heavily (up to 35% of the root length) colonized by several nonmycorrhizal fungi such as Olpidium, Polymyxa, and Gaeumannomyces–Phialophora complex. Canola roots, as expected, were not colonized by any mycorrhizal fungi but were colonized by O. brassicae Reduced tillage intensity altered the concentration of some nutrients in the leaves of mycorrhizal host plants (maize and wheat) but did not change those in nonhost canola. Changes in nutrient concentrations in maize and wheat leaves were likely due to the combined effects of colonization of their roots by various mycorrhizal and nonmycorrhizal fungi and not to some changes in the physical or chemical properties of soils. Cluster analysis showed that Mn concentration in wheat leaves was closely related to the Gaeumannomyces–Phialophora complex and concentrations of Ca, K, and Zn were related to tillage intensity and to the Polymyxa colonization of roots. We conclude that the colonization of roots by nonmycorrhizal root parasites, and especially by nonfilamentous obligate fungi, need to be taken into account in mycorrhizal studies conducted under field conditions.

show abstract

Section: Resultsmentioning

confidence: 99%

Tillage Intensity, Mycorrhizal and Nonmycorrhizal Fungi, and Nutrient Concentrations in Maize, Wheat, and Canola

Mozafar

Anken²,

Ruh

et al. 2000

Agronomy Journal

View full text Add to dashboard Cite

show abstract

“…Some soils are known to be suppressive to take‐all disease. The reasons for this are often uncertain but it may result from effects on the pathogen (growth rate and/or population structure), the host (host susceptibility) or the balance of antagonistic microflora in the soil (Bateman et al ., 1997; Hornby, 1983; Rengel, 1997; Rovira and Wildermuth, 1981; Walker, 1975). General suppression increases with increasing microbial biomass in the soil (Weller et al ., 2002).…”

Section: Take‐all Disease Of Wheat and Its Controlmentioning

confidence: 99%

Gaeumannomyces graminis, the take‐all fungus and its relatives

Freeman

Ward

2004

Molecular Plant Pathology

103

View full text Add to dashboard Cite

SUMMARY Take‐all, caused by the fungus Gaeumannomyces graminis var. tritici, is the most important root disease of wheat worldwide. Many years of intensive research, reflected by the large volume of literature on take‐all, has led to a considerable degree of understanding of many aspects of the disease. However, effective and economic control of the disease remains difficult. The application of molecular techniques to study G. graminis and related fungi has resulted in some significant advances, particularly in the development of improved methods for identification and in elucidating the role of the enzyme avenacinase as a pathogenicity determinant in the closely related oat take‐all fungus (G. graminis var. avenae). Some progress in identifying other factors that may be involved in determining host range and pathogenicity has been made, despite the difficulties of performing genetic analyses and the lack of a reliable transformation system.

show abstract

“…(Rengel, 1997a;Guest et al, 2002), thus depriving the host root of Mn, weakening root cell walls, and making roots susceptible to infection (Rengel et al, 1996).…”

Section: Microflora Influencing Mn Availabilitymentioning

confidence: 99%

Availability of Mn, Zn and Fe in the rhizosphere

Rengel

2015

J. Soil Sci. Plant Nutr.

213

186

View full text Add to dashboard Cite

This review paper critically assesses the literature on soil-microbe-plant interactions influencing availability of micronutrients in the rhizosphere. The emphasis is placed on Zn and Mn, but Fe is also covered to some extent.Micronutrient availability in the rhizosphere is controlled by soil and plant properties, and interactions of roots with microorganisms and the surrounding soil. Plants exude a variety of organic compounds (carboxylate anions, phenolics, carbohydrates, amino acids, enzymes, etc.) and inorganic ions (protons, phosphate, etc.) to change chemistry and biology of the rhizosphere and increase micronutrient availability. Increased availability may result from solubilization and mobilization by short-chain organic acid anions, amino acids and other low-molecular-weight organic compounds. Acidification of the rhizosphere soil increases mobilization of micronutrients (eg. for Zn, 100-fold increase in solubility for each unit of pH decrease).For diffusion-supplied micronutrients, the uptake rate is governed by the soil nutrient supply. Fertilisation with micronutrients (more so in case of Zn than Fe) can be effective in increasing the concentration of micronutrients at the soil-root interface. In addition, micronutrient-efficient crops and genotypes can increase an available nutrient fraction and hence increase micronutrient uptake.Our understanding of the physiological processes governing exudation and the soil-plant-microbe interactions in the rhizosphere is currently inadequate, especially in terms of spatial and temporal variability in root exudation as well as the fate and effectiveness of organic and inorganic compounds in increasing availability of soil micronutrients and undesirable trace elements. The interactions between microorganisms and plants at the soilroot interface are particularly important as well obscure.

show abstract

Decreased capacity of take‐all fungus to oxidize manganous ions is associated with take‐all decline

Cited by 11 publications

References 9 publications

Tillage Intensity, Mycorrhizal and Nonmycorrhizal Fungi, and Nutrient Concentrations in Maize, Wheat, and Canola

Tillage Intensity, Mycorrhizal and Nonmycorrhizal Fungi, and Nutrient Concentrations in Maize, Wheat, and Canola

Gaeumannomyces graminis, the take‐all fungus and its relatives

Availability of Mn, Zn and Fe in the rhizosphere

Contact Info

Product

Resources

About