scholarly journals Nonhost Resistance of Barley Is Successfully Manifested Against Magnaporthe grisea and a Closely Related Pennisetum-Infecting Lineage but Is Overcome by Magnaporthe oryzae

2006 ◽  
Vol 19 (9) ◽  
pp. 1014-1022 ◽  
Author(s):  
Nina Zellerhoff ◽  
Birgit Jarosch ◽  
Johannes Z. Groenewald ◽  
Pedro W. Crous ◽  
Ulrich Schaffrath

Magnaporthe oryzae is a major pathogen of rice (Oryza sativa L.) but is also able to infect other grasses, including barley (Hordeum vulgare L.). Here, we report a study using Magnaporthe isolates collected from other host plant species to evaluate their capacity to infect barley. A nonhost type of resistance was detected in barley against isolates derived from genera Pennisetum (fontaingrass) or Digitaria (crabgrass), but no resistance occurred in response to isolates from rice, genus Eleusine (goosegrass), wheat (Triticum aestivum L.), or maize (Zea mays L.), respectively. Restriction of pathogen growth in the nonhost interaction was investigated microscopically and compared with compatible interactions. Real-time polymerase chain reaction was used to quantify fungal biomass in both types of interaction. The phylogenetic relationship among the Magnaporthe isolates used in this study was investigated by inferring gene trees for fragments of three genes, actin, calmodulin, and β-tubulin. Based on phylogenetic analysis, we could distinguish different species that were strictly correlated with the ability of the isolates to infect barley. We demonstrated that investigating specific host interaction phenotypes for a range of pathogen isolates can accurately highlight genetic diversity within a pathogen population.

1996 ◽  
Vol 51 (9-10) ◽  
pp. 698-710 ◽  
Author(s):  
Donald E. Moreland ◽  
Thomas J. Fleischmann ◽  
Frederick T. Corbin ◽  
Janis E. McFarland

Microsomes isolated from excised shoots of 3-day-old. dark grown, grain sorghum [Sorghum bicolor (L.) Moench, Funk G522DR and DK 41Y] and corn seedlings [Zea mays (L.), Pioneer 3245] metabolized the sulfonylurea herbicide prosulfuron (CGA-152005). Corn microsomes predominantly formed a single major metabolite that resulted from hydroxylation of the phenyl ring at the C5 position. However, sorghum microsomes formed two major metabolites in an approximate 1:1 ratio. One was the 5-hydroxyphenyl metabolite, whereas the second metabolite resulted from ö-demethylation at C4 of the triazine ring. Metabolite identity was established by mass spectrometry and co-chromatography with authentic standards. Metabolism in both corn and sorghum was greatly enhanced by pretreatment of the seed with naphthalic anhydride and by subirrigation with 2.5% ethanol 24 h prior to harvest. Metabolism required a reduced pyridine nucleotide and was affected by several cytochrome P450 monooxygenase inhibitors (carbon monoxide, tetcyclacis, piperonyl butoxide, 1 aminobenzotriazole, and SKF-525A). The inhibitors differentially affected metabolism of prosulfuron. Microsomal oxidations from both untreated and inducer-treated tissue responded similarly to the inhibitors. In exploratory studies, microsomes isolated from shoots of wheat [Triticum aestivum L., Pioneer 2548], barley [Hordeum vulgare L., Boone], oats [Avena sativa L., Southern States 76-30-P242] and rice [Oryza sativa L„ Gulfmont], and room ripened avocado [Persea americana, Mill., Hass] mesocarp tissue also primarily formed the 5-hydroxyphenyl metabolite. Titration of seven different avocado microsomal preparations with prosulfuron provided typical type I difference spectra from which an average binding constant (Ks) of 187 ± 35 μm was obtained


2016 ◽  
Vol 71 (3) ◽  
pp. 37-50
Author(s):  
KAROLINA DUDZIAK ◽  
MICHAŁ NOWAK ◽  
KRZYSZTOF KOWALCZYK

Progress in cereals transformation which can be observed for last two decades has great importance in the development of plant science and agriculture. So far, non-vector techniques, particularly direct gene transfer using „gene gun”, have been often applied in cereals transformation. However, agrobiotechnology achievements enabled cereals transformation with the soil bacterium Agrobacterium tumefaciens. Initially, it was believed that this technique cannot be applied to cereals because monocotyledones are outside the host range of the crown gall disease. Nowadays, the top five cereals with the highest economic significance – rice (Oryza sativa L.), maize (Zea mays L.), wheat (Triticum aestivum L.), barley (Hordeum vulgare L.) and sorghum (Sorghum bicolor L.) are quite efficiently transformed by A. tumefaciens. By means of molecular genetic tools it is possible to obtain cereals with new, improved traits. The present paper is focused on agricultural development which can by observed by the application of GM cereals tolerant to biotic and abiotic stress factors. Moreover, we summarized the latest achievements in cereals transformation.


2010 ◽  
Vol 37 (4) ◽  
pp. 275 ◽  
Author(s):  
Peter R. Ryan ◽  
Emmanuel Delhaize

Suspicions that soluble aluminium (Al) is detrimental to plant growth were reported more than 100 years ago. The rhizotoxicity of Al3+ is now accepted as the major limitation to plant production on acidic soils. Plants differ in their susceptibility to Al3+ toxicity and significant variation can occur within species, even in some major crops. The physiology of Al3+ resistance in some species has been understood for 15 years but the molecular biology has been elucidated only recently. The first gene controlling Al3+ resistance was cloned from wheat (Triticum aestivum L.) in 2004 but others have now been identified in Arabidopsis, barley (Hordeum vulgare L.), rye (Secale cereale L.), sorghum (Sorghum bicolour (L.) Moench) and rice (Oryza sativa L.) with strong additional candidates in wheat and oilseed rape (Brassica napus L.). These genes confer resistance in different ways, but one mechanism occurs in nearly all species examined so far. This mechanism relies on the release of organic anions from roots which bind with the harmful Al3+ cations in the apoplast and detoxify them. The genes controlling this response come from at least two distinct families, suggesting that convergent evolution has occurred. We discuss the processes driving this convergence of protein function and offer opinions for why organic anions are central to the mechanisms of resistance in disparate species. We propose that mutations which modify protein expression or their activation by Al3+ have played important roles in co-opting different transport proteins from other functions.


2013 ◽  
Vol 36 (4) ◽  
pp. 439 ◽  
Author(s):  
Adriana Morales-Ortega ◽  
Guillermo Niño-Medina ◽  
Elizabeth Carvajal-Millán ◽  
Alfonso Gardea-Béjar ◽  
Patricia Torres-Chávez ◽  
...  

Los arabinoxilanos ferulados son los principales polisacáridos no amiláceos de los granos de cereales, que se localizan en las paredes celulares del endospermo, en la capa aleurona y en el pericarpio de los mismos. Estos polisacáridos se han reportado en los cereales más importantes, como trigo (Triticum aestivum L.), centeno (Secale cereale L. M. Bieb.), cebada (Hordeum vulgare L.), avena (A. sativa), arroz (Oryza sativa L.), sorgo (Sorghum vulgare), maíz (Zea mays L.) y mijo (Panicum miliaceum L.). Recientemente se han realizado esfuerzos enfocados a la extracción de arabinoxilanos ferulados a partir de subproductos de la industria procesadora de cereales, como de los pericarpios de maíz y de trigo, así como del “nejayote” que es el agua residual de la nixtamalización del maíz. Los arabinoxilanos ferulados forman soluciones viscosas y pueden formar geles bajo la acción de ciertos agentes oxidantes. Además, presentan características físico-químicas determinantes para su capacidad gelificante. Los geles de arabinoxilanos han despertado un gran interés debido a que presentan características interesantes como: olor y sabor neutro; estabilidad al pH, a los cambios de temperatura y de concentración de electrolitos; así como una estructura macroporosa. Estas características les confieren aplicación potencial como matrices para la liberación controlada de biomoléculas en aplicaciones alimentarias y no alimentarias, lo cual podría dar valor agregado a los cereales o subproductos de cereales de los cuales pueden ser extraídos estos polisacáridos. Esta revisión incluye los reportes más recientes sobre las características fisicoquímicas y la capacidad gelificante de arabinoxilanos ferulados, tema sobre el cual ha resurgido el interés en los últimos diez años. La generación de nuevo conocimiento sobre este polisacárido y sus geles podría sentar las bases para su aplicación en distintas áreas como la agroalimentaria, la biomédica y la cosmética, entre otras.


2020 ◽  
Author(s):  
Ian Sims ◽  
K Middleton ◽  
AG Lane ◽  
AJ Cairns ◽  
A Bacic

Microscopic examination of suspension-cultured cells of Phleum pratense L., Panicum miliaceum L., Phalaris aquatica L. and Oryza sativa L. showed that they were comprised of numerous root primordia. Polysaccharides secreted by these suspension cultures contained glycosyl linkages consistent with the presence of high proportions of root mucilage-like polysaccharides. In contrast, suspension-cultured cells of Hordeum vulgare L. contained mostly undifferentiated cells more typical of plant cells in suspension culture. The polysaccharides secreted by H. vulgare cultures contained mostly linkages consistent with the presence of glucuronoarabinoxylan. The soluble polymers secreted by cell-suspension cultures of Phleum pratense contained 70% carbohydrate, 14% protein and 6% inorganic material. The extracellular polysaccharides were separated into four fractions by anion-exchange chromatography using a gradient of imidazole-HCl at pH 7.0. From glycosyl-linkage analyses, five polysaccharides were identified: an arabinosylated xyloglucan (comprising 20% of the total polysaccharide), a glucomannan (6%), a type-II arabinogalactan (an arabinogalactan-protein; 7%), an acidic xylan (3%), and a root-slime-like polysaccharide, which contained features of type-II arabinogalactans and glucuronomannans (65%).


2020 ◽  
Author(s):  
Ian Sims ◽  
K Middleton ◽  
AG Lane ◽  
AJ Cairns ◽  
A Bacic

Microscopic examination of suspension-cultured cells of Phleum pratense L., Panicum miliaceum L., Phalaris aquatica L. and Oryza sativa L. showed that they were comprised of numerous root primordia. Polysaccharides secreted by these suspension cultures contained glycosyl linkages consistent with the presence of high proportions of root mucilage-like polysaccharides. In contrast, suspension-cultured cells of Hordeum vulgare L. contained mostly undifferentiated cells more typical of plant cells in suspension culture. The polysaccharides secreted by H. vulgare cultures contained mostly linkages consistent with the presence of glucuronoarabinoxylan. The soluble polymers secreted by cell-suspension cultures of Phleum pratense contained 70% carbohydrate, 14% protein and 6% inorganic material. The extracellular polysaccharides were separated into four fractions by anion-exchange chromatography using a gradient of imidazole-HCl at pH 7.0. From glycosyl-linkage analyses, five polysaccharides were identified: an arabinosylated xyloglucan (comprising 20% of the total polysaccharide), a glucomannan (6%), a type-II arabinogalactan (an arabinogalactan-protein; 7%), an acidic xylan (3%), and a root-slime-like polysaccharide, which contained features of type-II arabinogalactans and glucuronomannans (65%).


Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1482
Author(s):  
Silvia Pampana ◽  
Alessandro Rossi ◽  
Iduna Arduini

Winter cereals are excellent candidates for biosolid application because their nitrogen (N) requirement is high, they are broadly cultivated, and their deep root system efficiently takes up mineral N. However, potential N leaching from BS application can occur in Mediterranean soils. A two-year study was conducted to determine how biosolids affect biomass and grain yield as well as N uptake and N leaching in barley (Hordeum vulgare L.), common wheat (Triticum aestivum L.), durum wheat (Triticum turgidum L. var. durum), and oat (Avena byzantina C. Koch). Cereals were fertilized at rates of 5, 10, and 15 Mg ha−1 dry weight (called B5, B10, and B15, respectively) of biosolids (BS). Mineral-fertilized (MF) and unfertilized (C) controls were included. Overall, results highlight that BS are valuable fertilizers for winter cereals as these showed higher yields with BS as compared to control. Nevertheless, whether 5 Mg ha−1 of biosolids could replace mineral fertilization still depended on the particular cereal due to the different yield physiology of the crops. Moreover, nitrate leaching from B5 was comparable to MF, and B15 increased the risk by less than 30 N-NO3 kg ha−1. We therefore concluded that with specific rate settings, biosolid application can sustain yields of winter cereals without significant additional N leaching as compared to MF.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
M. K. Prasannakumar ◽  
P. Buela Parivallal ◽  
Devanna Pramesh ◽  
H. B. Mahesh ◽  
Edwin Raj

AbstractRice blast (caused by Magnaporthe oryzae) and sheath rot diseases (caused by Sarocladium oryzae) are the most predominant seed-borne pathogens of rice. The detection of both pathogens in rice seed is essential to avoid production losses. In the present study, a microdevice platform was designed, which works on the principles of loop-mediated isothermal amplification (LAMP) to detect M. oryzae and S. oryzae in rice seeds. Initially, a LAMP, polymerase chain reaction (PCR), quantitative PCR (qPCR), and helicase dependent amplification (HDA) assays were developed with primers, specifically targeting M. oryzae and S. oryzae genome. The LAMP assay was highly efficient and could detect the presence of M. oryzae and S. oryzae genome at a concentration down to 100 fg within 20 min at 60 °C. Further, the sensitivity of the LAMP, HDA, PCR, and qPCR assays were compared wherein; the LAMP assay was highly sensitive up to 100 fg of template DNA. Using the optimized LAMP assay conditions, a portable foldable microdevice platform was developed to detect M. oryzae and S. oryzae in rice seeds. The foldable microdevice assay was similar to that of conventional LAMP assay with respect to its sensitivity (up to 100 fg), rapidity (30 min), and specificity. This platform could serve as a prototype for developing on-field diagnostic kits to be used at the point of care centers for the rapid diagnosis of M. oryzae and S. oryzae in rice seeds. This is the first study to report a LAMP-based foldable microdevice platform to detect any plant pathogens.


1977 ◽  
Vol 57 (3) ◽  
pp. 729-733 ◽  
Author(s):  
L. C. DARLINGTON ◽  
D. E. MATHRE ◽  
R. H. JOHNSTON

Isolates of Claviceps purpurea (Fr.) Tul. originally isolated from many different grass hosts in the northern Great Plains and several other areas in the United States and England were tested for their pathogenicity to selected cultivars or lines of male-sterile wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.). While there was a great range in the level of virulence, no clear-cut evidence of specific races was obtained. A few isolates were weakly virulent on two cultivars of male-sterile spring wheat but were highly virulent on the other two cultivars tested. Wheat and barley breeders are advised to use a mixture of isolates in screening germ plasm for resistance to ergot.


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