Cellular characteristics of temporary partial breakdown of mlo- resistance in barley to powdery mildew

Baker, S.J.; Newton, A. C.; Gurr, Sarah J.

doi:10.1006/pmpp.1999.0242

Cited by 16 publications

(13 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This reduction is both in the frequency at primary germ tube interaction sites after 7 hpi and in the apposition size at appressorial germ tube interaction sites 24 hpi, and indicates a delayed or reduced resistance mechanism induction during the recovery period. 3 The cultivar 'Krona', which also carries the mlo11 gene, shows some breakdown after release of drought stress, whereas other cultivars, such as 'Golden Promise', with the wild-type dominant Mlo, do not. 1 Clearly, there are genetic differences in cellular response to powdery mildew in barley genotypes prone to breakdown of resistance expression following relief of drought stress.…”

Section: Introductionmentioning

confidence: 99%

Effects of drought stress and its sudden relief on free radical processes in barley

Goodman¹,

Newton²

2004

J Sci Food Agric

View full text Add to dashboard Cite

The generation of free radicals and other paramagnetic species has been investigated by electron paramagnetic resonance (EPR) spectroscopy in leaves of barley plants during and after release of drought stress. Three cultivars were studied; the mlo-resistant spring barley cultivars, Atem and Krona, along with the cultivar Golden Promise, with the wild-type dominant Mlo. In the cultivar Atem, which exhibits a partial loss of resistance to powdery mildew after relief of drought stress, the free radical levels were elevated in the drought-stressed samples compared with those seen in the controls, but they returned rapidly to the control levels after release of the stress. The other two cultivars showed little or no change in the free radical signal for any of the treatments. A sizeable increase in the level of a mononuclear Fe(III) complex was seen in the droughted samples (compared with the levels in the watered controls), and these elevated levels remained after release of the stress. These observations are discussed in the context of molecular processes in the mesophyll cells, where activation of plasma membrane H+-ATPase by 14-3-3 proteins leads to a decrease in pH. This, in turn, perturbs the Fe(II) speciation in favour of more easily oxidized complexes, and results in the generation of the mononuclear Fe(III) complex. The greater change in free radical activity in Atem as a result of drought stress compared with that seen with the other cultivars indicates that it is affected to a greater extent by the stress.

show abstract

Section: Introductionmentioning

confidence: 99%

Effects of drought stress and its sudden relief on free radical processes in barley

Goodman¹,

Newton²

2004

J Sci Food Agric

View full text Add to dashboard Cite

show abstract

“…These outbreaks are sporadic and transient, and do not appear to be due to genetic changes in the powdery mildew population (see later), but appear Plant Genetics and Breeding related to unusual environmental conditions [30]. Experimentally it was shown that relief from water stress in barley cultivars might result in temporary partial breakdown of mlo resistance both under controlled greenhouse conditions and in field experiments [7,8,40] (Tab. I).…”

Section: Environmental Factorsmentioning

confidence: 99%

“…Stomatal subsidiary cells, the very small epidermal cells directly adjacent to guard cells, are penetrated with a slightly greater frequency than short cells e.g. [5,8,31]. The phenomenon of enhanced subsidiary cell susceptibility to powdery mildew infection in cereals is well established e.g.…”

Section: Cell Typesmentioning

confidence: 99%

“…Relief from water stress increased susceptibility of both Mlo susceptible and mlo resistant barley for a short period of time, with maximum mildew infection frequency being attained when the water stress was relieved approximately seven hours after powdery mildew inoculation [8]. The extent of resistance breakdown also depended on the genetic background of the barley in which the mlo-gene was contained, and not the actual mlo mutant used [8]. Some barley genotypes do not suffer from breakdown after relief of water stress and QTL mapping has demonstrated that at least one locus independent of the mlo gene is responsible for this characteristic (Newton, unpublished data).…”

Section: Environmental Factorsmentioning

confidence: 99%

See 1 more Smart Citation

The Barley mlo-gene: an important powdery mildew resistance source

Lyngkjær¹,

Newton²,

et al. 2000

View full text Add to dashboard Cite

“…Genotypic effects on cell size have been reported in a number of crop species, and significantly, some of these effects (caused by dwarfing genes) have also been shown to influence host pathogen interactions [42]. We know that resistance response to pathogen challenge is affected by cell type and size [43]. Similar effects have been proposed due to variation in hyphal cell size in fungi [44], whilst variation in contribution to qPCR based estimates of fungal colonisation have been reported between spores and hyphae [45].…”

Section: Molecular Detection and Quantification Of Crop Pathogensmentioning

confidence: 99%

Assessing the Consequences of Microbial Infection in Field Trials: Seen, Unseen, Beneficial, Parasitic and Pathogenic

Looseley

Newton

2014

Agronomy

View full text Add to dashboard Cite

Microbial infections of crop plants present an ongoing threat to agricultural production. However, in recent years, we have developed a more nuanced understanding of the ecological role of microbes and how they interact with plants. This includes an appreciation of the influence of crop physiology and environmental conditions on the expression of disease symptoms, the importance of non-pathogenic microbes on host plants and pathogens, and the capacity for plants to act as hosts for human pathogens. Alongside this we now have a variety of tools available for the identification and quantification of microbial infections on crops grown under field conditions. This review summarises some of the consequences of microbial infections in crop plants, and discusses how new and established assessment tools can be used to understand these processes. It challenges our current assumptions in yield loss relationships and offers understanding of the potential for more resilient crops.

show abstract

Cellular characteristics of temporary partial breakdown of mlo- resistance in barley to powdery mildew

Cited by 16 publications

References 21 publications

Effects of drought stress and its sudden relief on free radical processes in barley

Effects of drought stress and its sudden relief on free radical processes in barley

The Barley mlo-gene: an important powdery mildew resistance source

Assessing the Consequences of Microbial Infection in Field Trials: Seen, Unseen, Beneficial, Parasitic and Pathogenic

Contact Info

Product

Resources

About