Showing papers on "Rust published in 2012"
01 Jan 2012
TL;DR: In this paper, the authors used field rust reaction and flanking markers to identify two F6 RILs, Arula1 and Arula2, from the above population that lacked Lr34 and Lr46 but carried the leaf rust resistance gene in 7BL, hereby designated Lr68.
Abstract: The common wheat cultivar Parula possesses a high level of slow rusting, adult plant resistance (APR) to all three rust diseases of wheat. Previous mapping studies using an Avocet-YrA/Parula recombinant inbred line (RIL) population showed that APR to leaf rust (Puccinia tritici- na) in Parula is governed by at least three independent slow rusting resistance genes: Lr34 on 7DS, Lr46 on 1BL, and a previously unknown gene on 7BL. The use of field rust reaction and flanking markers identified two F6 RILs, Arula1 and Arula2, from the above population that lacked Lr34 and Lr46 but carried the leaf rust resistance gene in 7BL, hereby designated Lr68. Arula1 and Arula2 were crossed with Apav, a highly susceptible line from the cross Avocet-YrA/Pavon 76, and 396 F4-derived F5 RILs were developed for mapping Lr68. The RILs were phenotyped for leaf rust resistance for over 2 years in Ciudad Obregon, Mexico, with a mixture of P. triticina races MBJ/SP and MCJ/SP. Close genetic linkages with several DNA markers on 7BL were established using 367 RILs; Psy1-1 and gwm146 flanked Lr68 and were estimated at 0.5 and 0.6 cM, respectively. The relationship between Lr68 and the race-specific seedling resistance gene Lr14b, located in the same region and present in Parula, Arula1 and Arula2, was investigated by evaluating the RILs with Lr14b-avir- ulent P. triticina race TCT/QB in the greenhouse. Although Lr14b and Lr68 homozygous recombinants in repulsion were not identified in RILs, c-irradiation-induced deletion stocks that lacked Lr68 but possessed Lr14b showed that Lr68 and Lr14b are different loci. Flanking DNA markers that are tightly linked to Lr68 in a wide array of genotypes can be utilized for selection of APR to leaf rust.
237 citations
TL;DR: The promise, problems and progress of utilizing hematite for photocatalyzed water oxidation and issues which require further research are presented.
Abstract: This article focuses on the promise, problems and progress of utilizing hematite for photocatalyzed water oxidation. Issues which require further research are also presented.
160 citations
TL;DR: The development of uniform and severe epidemics facilitated excellent phenotyping, and when combined with multi-environment analysis, resulted in the relatively large number of QTLs identified in this study.
Abstract: Leaf rust and stripe rust are important diseases of wheat world-wide and deployment of cultivars with genetic resistance is an effective and environmentally sound control method. The use of minor, additive genes conferring adult plant resistance (APR) has been shown to provide resistance that is durable. The wheat cultivar ‘Pastor’ originated from the CIMMYT breeding program that focuses on minor gene-based APR to both diseases by selecting and advancing generations alternately under leaf rust and stripe rust pressures. As a consequence, Pastor has good resistance to both rusts and was used as the resistant parent to develop a mapping population by crossing with the susceptible ‘Avocet’. All 148 F5 recombinant inbred lines were evaluated under artificially inoculated epidemic environments for leaf rust (3 environments) and stripe rust (4 environments, 2 of which represent two evaluation dates in final year due to the late build-up of a new race virulent to Yr31) in Mexico. Map construction and QTL analysis were completed with 223 polymorphic markers on 84 randomly selected lines in the population. Pastor contributed Yr31, a moderately effective race-specific gene for stripe rust resistance, which was overcome during this study, and this was clearly shown in the statistical analysis. Linked or pleiotropic chromosomal regions contributing to resistance against both pathogens included Lr46/Yr29 on 1BL, the Yr31 region on 2BS, and additional minor genes on 5A, 6B and 7BL. Other minor genes for leaf rust resistance were located on 1B, 2A and 2D and for stripe rust on 1AL, 1B, 3A, 3B, 4D, 6A, 7AS and 7AL. The 1AL, 1BS and 7AL QTLs are in regions that were not identified previously as having QTLs for stripe rust resistance. The development of uniform and severe epidemics facilitated excellent phenotyping, and when combined with multi-environment analysis, resulted in the relatively large number of QTLs identified in this study.
154 citations
TL;DR: In this paper, the authors investigated a reinforced concrete specimen that had deteriorated in an artificial environment for 2.5 years and observed the crack width and the rust distribution by digital microscopy.
132 citations
TL;DR: In this article, the evolution of rust on MnCuP weathering steel submitted to a simulated coastal atmosphere was investigated by corrosion weight gain, scanning electron microscopy, and electrochemical methods.
108 citations
TL;DR: A strong LD in the Bru1 region and strong associations between most of the markers and rust resistance are revealed, revealing that it constitutes the main source of brown rust resistance in modern cultivars.
Abstract: Modern sugarcane cultivars (Saccharum spp., 2n = 100–130) are high polyploid, aneuploid and of interspecific origin. A major gene (Bru1) conferring resistance to brown rust, caused by the fungus Puccinia melanocephala, has been identified in cultivar R570. We analyzed 380 modern cultivars and breeding materials covering the worldwide diversity with 22 molecular markers genetically linked to Bru1 in R570 within a 8.2 cM segment. Our results revealed a strong LD in the Bru1 region and strong associations between most of the markers and rust resistance. Two PCR markers, that flank the Bru1-bearing segment, were found completely associated with one another and only in resistant clones representing efficient molecular diagnostic for Bru1. On this basis, Bru1 was inferred in 86 % of the 194 resistant sugarcane accessions, revealing that it constitutes the main source of brown rust resistance in modern cultivars. Bru1 PCR diagnostic markers should be particularly useful to identify cultivars with potentially alternative sources of resistance to diversify the basis of brown rust resistance in breeding programs.
100 citations
TL;DR: In this paper, the evolution of atmospheric corrosion of MnCuP weathering steel in a simulated coastal industrial atmosphere was investigated by weight gain, SEM, XRD, and electrochemical measurements.
90 citations
TL;DR: In this article, the authors investigated three electrochemically corroded reinforced concrete specimens and measured the thickness of the rust layer at inner and outer surface cracking of concrete cover by digital microscopy.
79 citations
TL;DR: There was no correspondence between the organisms that promoted seedling growth and those that reduced coffee leaf rust severity on seedlings or leaf discs.
56 citations
TL;DR: The results support the concept that a plant's innate ability to absorb Si will dictate the benefits conferred by a treatment with Si and provide evidence that Si can protect soybean plants against soybean rust through mediated resistance.
Abstract: Arsenault-Labrecque, G., Menzies, J. G., and Belanger, R. R. 2012. Effect of silicon absorption on soybean resistance to Phakopsora pachyrhizi in different cultivars. Plant Dis. 96:37-42. Silicon (Si) is recognized for its prophylactic role in alleviating diseases when absorbed by plants and has been proposed as a possible solution against soybean rust, caused by Phakopsora pachyrhizi. However, little is known about its potential effects on soybean (Glycine max) because the plant’s ability to absorb Si is poorly defined. In this work, our objectives were to evaluate and quantify the absorption of Si in leaves of different soybean cultivars and to determine if such absorption was able to enhance resistance to soybean rust. In a first set of experiments with cv. Williams 82, hydroponic plants were supplied or not with Si and inoculated with urediniospores of P. pachyrhizi. Chemical analyses revealed no significant differences in the plants’ Si content regardless of the treatment, which translated into no effect on rust incidence. However, in a second set of experiments with different cultivars, plants of Korean cultivar Hikmok sorip absorbed nearly four times more Si than those of Williams 82. At the same time, plants from this cultivar exhibited a near absence of disease symptoms when supplied with Si. This resistance appeared to be the result of hypersensitive (HR) reactions that were triggered when plants were fed with Si. These results support the concept that a plant’s innate ability to absorb Si will dictate the benefits conferred by a treatment with Si and provide evidence that Si can protect soybean plants against soybean rust through mediated resistance.
53 citations
TL;DR: The aim of this study was to elucidate the inheritance of rust resistance and male fertility restoration and identify the chromosome location of the underlying genes in Rf ANN-1742, an ‘HA 89’ backcross restorer line derived from wild annual sunflower, which was identified as resistant to the newly emerged rust races.
Abstract: Sunflower oil is one of the major sources of edible oil. As the second largest hybrid crop in the world, hybrid sunflowers are developed by using the PET1 cytoplasmic male sterility system that contributes to a 20 % yield advantage over the open-pollinated varieties. However, sunflower production in North America has recently been threatened by the evolution of new virulent pathotypes of sunflower rust caused by the fungus Puccinia helianthi Schwein. Rf ANN-1742, an 'HA 89' backcross restorer line derived from wild annual sunflower (Helianthus annuus L.), was identified as resistant to the newly emerged rust races. The aim of this study was to elucidate the inheritance of rust resistance and male fertility restoration and identify the chromosome location of the underlying genes in Rf ANN-1742. Chi-squared analysis of the segregation of rust response and male fertility in F(2) and F(3) populations revealed that both traits are controlled by single dominant genes, and that the rust resistance gene is closely linked to the restorer gene in the coupling phase. The two genes were designated as R ( 11 ) and Rf5, respectively. A set of 723 mapped SSR markers of sunflower was used to screen the polymorphism between HA 89 and the resistant plant. Bulked segregant analysis subsequently located R ( 11 ) on linkage group (LG) 13 of sunflower. Based on the SSR analyses of 192 F(2) individuals, R ( 11 ) and Rf5 both mapped to the lower end of LG13 at a genetic distance of 1.6 cM, and shared a common marker, ORS728, which was mapped 1.3 cM proximal to Rf5 and 0.3 cM distal to R ( 11 ) (Rf5/ORS728/R ( 11 )). Two additional SSRs were linked to Rf5 and R ( 11 ): ORS995 was 4.5 cM distal to Rf5 and ORS45 was 1.0 cM proximal to R ( 11 ). The advantage of such an introduced alien segment harboring two genes is its large phenotypic effect and simple inheritance, thereby facilitating their rapid deployment in sunflower breeding programs. Suppressed recombination was observed in LGs 2, 9, and 11 as it was evident that no recombination occurred in the introgressed regions of LGs 2, 9, and 11 detected by 5, 9, and 22 SSR markers, respectively. R ( 11 ) is genetically independent from the rust R-genes R ( 1 ), R ( 2 ), and R ( 5 ), but may be closely linked to the rust R-gene R ( adv ) derived from wild Helianthus argophyllus, forming a large rust R-gene cluster of R ( adv )/R ( 11 )/R ( 4 ) in the lower end of LG13. The relationship of Rf5 with Rf1 is discussed based on the marker association analysis.
TL;DR: In this paper, the authors used in situ Raman spectroscopy to characterize the rust in Evans' droplet experiments, and found that the rust formed in the central anodic pitting area was green rust, while the rust clusters precipitated in between the pitting areas and the peripheral cathodic area was lepidocrocite.
TL;DR: Introgression, inheritance and molecular mapping of a leaf rust resistance gene of Ae.
Abstract: Rusts are the most important biotic constraints limiting wheat productivity worldwide Deployment of cultivars with broad spectrum rust resistance is the only environmentally viable option to combat these diseases Identification and introgression of novel sources of resistance is a continuous process to combat the ever evolving pathogens The germplasm of nonprogenitor Aegilops species with substantial amount of variability has been exploited to a limited extent In the present investigation introgression, inheritance and molecular mapping of a leaf rust resistance gene of Ae caudata (CC) acc pau3556 in cultivated wheat were undertaken An F2 population derived from the cross of Triticum aestivum cv WL711 – Ae caudata introgression line T291-2 with wheat cultivar PBW343 segregated for a single dominant leaf rust resistance gene at the seedling and adult plant stages Progeny testing in F3 confirmed the introgression of a single gene for leaf rust resistance Bulked segregant analysis using polymorphic D-genome-specific SSR markers and the cosegregation of the 5DS anchored markers (Xcfd18, Xcfd78, Xfd81 and Xcfd189) with the rust resistance in the F2 population mapped the leaf rust resistance gene (LrAC) on the short arm of wheat chromosome 5D Genetic complementation and the linked molecular markers revealed that LrAC is a novel homoeoallele of an orthologue Lr57 already introgressed from the 5M chromosome of Ae geniculata on 5DS of wheat
Patent•
10 Oct 2012
TL;DR: In this paper, the authors proposed a volatile rust preventive oil, which comprises, by weight, 71-91% of base oil, 5-25% of an oil soluble volatile corrosion inhibitor, 1-5% of antirusting agent, 0.5-1% of mildew-proof agent and 1-6% of antioxidant.
Abstract: The invention discloses volatile rust preventive oil which comprises, by weight, 71-91% of base oil, 5-25% of an oil soluble volatile corrosion inhibitor, 1-5% of an antirusting agent, 1-6% of a cosolvent, 0.5-1% of a mildew-proof agent, 0.5-1% of an antifoaming agent and 1-6% of antioxidant, wherein the base oil is one of 500SN 46# machine oil, 32# machine oil, 600SN 150# machine oil and 100# machine oil; and the oil soluble volatile corrosion inhibitor is a mixture of four kinds of 2-heptadecenyl-imidalidine, octadecylamine, triazole tributylamine, dicyclohexylamine carbonate, dicyclohexylaminenitrite, benzotriazole, tert-butyl chromate, nephthenic soap, petroleum sodium sulfonate, sorbitan monooleate and stearic acid; and the antioxidant is sulfurphosphorousbutyloctyl zinc salt. The volatile rust preventive oil has good volatile rust preventive and corrosion resistant performances, metal which cannot be coated with rust preventive oil can achieve rust preventive protection, the operation is simple, and the cost is low.
TL;DR: In Colombia, coffee cultivation covers 850,000 ha, of which 41% comprises cultivars of Coffea arabica that are susceptible to leaf rust (CLR) caused by Hemileia vastatrix Berk, first recorded in Colombia in 1983.
Abstract: In Colombia, coffee cultivation covers 850,000 ha, of which 41% comprises cultivars of Coffea arabica that are susceptible to leaf rust (CLR) caused by Hemileia vastatrix Berk. et Br.CLR, first recorded in Colombia in 1983, is the most…
TL;DR: The results indicate that the ectomycorrhizal formation compensated the rust infection by a decrease in the flavonoid syntheses, which provides new evidence for an interactive response of mycorrhIZal colonization and infection with rust fungi in the metabolism of poplar.
Abstract: Fungal colonization can significantly affect the secondary metabolism of the host plants. We tested the impact of a common below-ground symbiosis, i.e., ectomycorrhiza formation, on poplar leaf chemical components that are involved in the defence against a common disease, i.e., rust fungi, in N-deficient soil. A rust-susceptible poplar clone ( Populus trichocarpa × deltoides ‘Beaupre’) was (a) non-associated with ectomycorrhizal fungus (EM) Hebeloma mesophaeum (Pers.) Quelet MUN and noninfected with rust fungus Melampsora larici-populina Kleb. (isolate 98AG31), (b) associated with EM, (c) inoculated with rust fungus and (d) associated with EM and inoculated with rust fungus. Poplar leaves were analysed by photometric and mass spectrometric techniques (liquid chromatography–tandem mass spectrometry (LC-MS/MS), pyrolysis–field ionization mass spectrometry (Py-FIMS)). Both rust infection and mycorrhiza formation led to increased proportions of condensed tannins in relation to total phenolics (13% in the control, 18–19% in the fungal treatments). In contrast, salicylic acid concentration (6.8 µg g −1 in the control) was higher only in the rust treatments (17.9 and 25.4 µg g −1 with rust infection). The Py-FIMS analysis revealed that the rust-infected treatments were significantly separated from the non-rust-infected treatments on the basis of six flavonoids and one lipid. The relative abundance of these components, which have known functions in plant defence, was decreased after rust infection of non-mycorrhizal plants, but not in mycorrhizal plants. The results indicate that the ectomycorrhizal formation compensated the rust infection by a decrease in the flavonoid syntheses. The study provides new evi dence for an interactive response of mycorrhizal colonization and infection with rust fungi in the metabolism of poplar.
TL;DR: The results revealed that dominant alleles at three loci conditioned resistance to soybean rust races found in Nigeria and the tentative symbols formulated for the three locis controlling resistance to rust in soybean were Rsbr1, Rsbr2 and Rsbr3.
Abstract: In searching for resistance genes to soybean rust (Phakopsora pachyrhizi (H. Sydow & Sydow), twenty eight soybean genotypes obtained from the International Institutefor Tropical Agriculture (IITA) Ibadan were screened on rust infested field for resistance to rust. These genotypeswere planted at the National Cereals Research Institute (NCRI), Yandev station in Benue State, Nigeria during 2007 and 2008 cropping seasons. Soybean rust is known to be endemic to the Yandev station. Field observations revealed significant variation among the soybean genotypes to rust. Seven soybean genotypes were identified to be resistant to rust which were TGx1987-62F, TGx1935-3F, TGx1951-3F, TGx1936-2F, TGx1987-10F, TGx1972-1F and TGx1949-8F. Genetic analysis of the parental materials after hybridization for the mode of inheritance indicated that rust resistance in soybean was monogenically controlled by dominant genes. The relationship among the resistance genes was established through allelic testing which indicated that genes in TGx1972-1F and TGx1987-10F are allelic and independent of the dominant resistance genes of TGx1951-3F, TGx1936-2F, TGx1987-62F and TGx1935- 3F which are also allelic. The results revealed that dominant alleles at three loci conditioned resistance to soybean rust races found in Nigeria and the tentative symbols formulated for the three loci controlling resistance to rust in soybean were Rsbr1, Rsbr2 and Rsbr3 (Resistance to soybean rust )
TL;DR: Using simple sequence repeats (SSR) and single nucleotide polymorphism (SNP) markers, the resistance gene in MBR1012 was mapped to the telomeric region of chromosome 1HS and assigned the temporary locus designation of RphMBR 1012 until it can be unequivocally determined to be different from all previously reported resistance genes.
Abstract: Leaf rust, caused by Puccinia hordei Otth, is an important disease of barley (Hordeum vulgare L.) in many areas of the world. The appearance of new virulent races necessitates the identification of new resistance genes in barley. Screening of spring barley landraces from former Yugoslavia led to the identifi- cation of an accession (MBR1012) carrying resistance to the most widespread virulent leaf rust pathotypes in
Patent•
14 Mar 2012
TL;DR: In this paper, a combination of inorganic acid, organic acid, 1-8% of osmotic agent selected from at least one of C2-C4 short chain ethers and short chain alcohols, 2-10% of sulfonic acid and / or sulfonate anionic surfactant, 0.5-10 percent of corrosion inhibitor and the balance of water was used.
Abstract: The invention provides a rust removal combination, including, based on a total weight of the composition, 10-20% of inorganic acid, 1-10% of organic acid, 1-8% of osmotic agent selected from at least one of C2-C4 short chain ethers and short chain alcohols, 2-10% of sulfonic acid and / or sulfonate anionic surfactant, 0.5-10% of corrosion inhibitor and the balance of water.
TL;DR: In this paper, the evolution of MnCuP weathering steel in a simulated industrial atmosphere as a function of corrosion duration was investigated by corrosion weight gain, scanning electron microscopy, X-ray diffraction, and electrochemical methods.
Abstract: The rusting evolution of MnCuP weathering steel in a simulated industrial atmosphere as a function of corrosion duration was investigated by corrosion weight gain, scanning electron microscopy, X-ray diffraction, and electrochemical methods. The results indicate that the corrosion kinetics is related closely to the rust composition and electrochemical properties. The corrosion rate is higher during the first corrosion stage, and it is lower during the second corrosion stage. During the first corrosion stage, the rust layer is in low density, discontinuous, and loose, with a lower relative abundance of α-FeOOH. During the second corrosion stage, a compact and protective inner rust layer forms with a higher relative abundance of α-FeOOH, contributing to enhanced rust layer resistance. The rust initially enhances and then stabilizes the cathodic process, but the anodic process tends to be inhibited by the protective rust layer. Electrochemical impedance spectroscopy tests indicate that it is more scientific to evaluate the rust layer protective ability by charge transfer resistance.
TL;DR: The identification of leaf rust infection-modulated defence responses restricted to the resistant NIL support the hypothesis that basal defence responses of Bowman, but not the Rph15 resistance gene-based ones, are suppressed or delayed by pathogen effectors to levels below the detection power of the adopted proteomic approach.
Abstract: Leaf rust, caused by the biotrophic fungal pathogen Puccinia hordei, is one of the most important foliar disease of barley (Hordeum vulgare) and represents a serious threat in many production regions of the world. The leaf rust resistance gene Rph15 is of outstanding interest for resistance breeding because it confers resistance to over 350 Puccinia hordei isolates collected from around the world. Molecular and biochemical mechanisms responsible for the Rph15 effectiveness are currently not investigated. The aim of the present work was to study the Rph15-based defence responses using a proteomic approach. Protein pattern changes in response to the leaf rust pathogen infection were investigated in two barley near isogenic lines (NILs), Bowman (leaf rust susceptible) and Bowman-Rph15 (leaf rust resistant), differing for the introgression of the leaf rust resistance gene Rph15. Two infection time points, 24 hours and four days post inoculation (dpi), were analysed. No statistically significant differences were identified at the early time point, while at 4 dpi eighteen protein spots were significantly up or down regulated with a fold-change equal or higher than two in response to pathogen infection. Almost all the pathogen-responsive proteins were identified in the Bowman-Rph15 resistant NIL. Protein spots were characterized by LC-MS/MS analysis and found to be involved in photosynthesis and energy metabolism, carbohydrate metabolism, protein degradation and defence. Proteomic data were complemented by transcriptional analysis of the respective genes. The identified proteins can be related to modulation of the photosynthetic apparatus components, re-direction of the metabolism to sustain defence responses and deployment of defence proteins. The identification of leaf rust infection-modulated defence responses restricted to the resistant NIL support the hypothesis that basal defence responses of Bowman, but not the Rph15 resistance gene-based ones, are suppressed or delayed by pathogen effectors to levels below the detection power of the adopted proteomic approach. Additionally, Rph15-mediated resistance processes identified mainly resides on a modulation of primary metabolism, affecting photosyntesis and carbohydrate pool.
TL;DR: In this article, the effects of chromium (Cr) addition on the corrosion resistance of low alloy steel used in flue gas desulfurization systems were examined by electrochemical (potentiodynamic polarization tests, linear polarization measurements and electrochemical impedance spectroscopy) and weight loss measurements in a 10 wt% H2SO4 solution at room temperature.
Abstract: The effects of a chromium (Cr) addition on the corrosion resistance of low alloy steel used in flue gas desulfurization systems were examined by electrochemical (potentiodynamic polarization tests, linear polarization measurements and electrochemical impedance spectroscopy) and weight loss measurements in a 10 wt% H2SO4 solution at room temperature. All measurements revealed a decrease in corrosion rate with increasing Cr content. SEM, EPMA and XPS examinations of the corroded surfaces after the immersion test indicated that 0.6% Cr addition decreased corrosion damage to the steels because protective Cr oxides formed in all the rust layers and Fe oxides dominated over Fe sulphate compounds in the inner rust layers.
TL;DR: Line MNG 8.10 showed adaptability to most of the locations and had the highest yield among the three most stable lines, making it the most promising line; it is therefore recommended for release to improve soybean production and productivity in the region.
Abstract: Asian soybean rust is a major threat to worldwide soybean production at present. Host plant resistance offers the most sustainable control strategy to resource poor farmers in sub-Saharan Africa and worldwide. Using 13 soybean lines bred for resistance to soybean rust, and 2 checks, yield trials were conducted at four regions of Uganda for four consecutive seasons to determine yield stability and reaction to soybean rust disease. An additive main effects and multiplicative interaction (AMMI) model was used to assess the yield stability of the soybean lines. Stable lines identified included MNG 7.13, MNG 8.10, and MNG 1.63, which showed the lowest environmental interaction. These lines also out-yielded the local checks by over 300 kg ha−1, indicating that they have potential to boost soybean yields in the tropics. Line MNG 8.10 showed adaptability to most of the locations and had the highest yield among the three most stable lines, making it the most promising line; it is therefore recommended for release to improve soybean production and productivity in the region.
TL;DR: In this article, the authors discuss the utilization of colour analyses for the assessment and rating of atmospheric corrosion products, whereas particular attention is spent to flash rusting, along with a brief review about the composition of flash rust.
Abstract: The paper reviews the utilization of colour analyses for the assessment and rating of atmospheric corrosion products, whereas particular attention is spent to flash rusting. The background of flash rust formation is discussed first, along with a brief review about the composition of flash rust. The fundamentals of the HSV colour model, which is selected as a simple suitable model, are introduced. Finally, the author discusses the utilization of the suggested approach for the evaluation of steel substrate cleanliness and rust assessment.
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01 Jan 2012
TL;DR: Host plant resistance is the most effective means to control the disease, hence, planting resistant cultivars is recommended, but different races of the fungus can occur from one year to the next and might overcome resistance.
Abstract: Stripe rust, or yellow rust, is primarily a foliar fungal disease of wheat, although it can infect spike and stem tissues. If the pathogen infects the spike (head) it causes extensive quality and grain yield loss. The disease is caused by the fungus Puccinia striiformis f. sp. tritici. The fungus can only survive and reproduce on wheat. It survives from one season to the next on volunteer plants. Mild winters and cooler wet weather in the spring and early summer favor the development of the disease. Host plant resistance is the most effective means to control the disease, hence, planting resistant cultivars is recommended. However, different races of the fungus can occur from one year to the next and might overcome resistance. A number of fungicides are labeled to control the disease but scouting and early detection are crucial to time pesticide applications for effective control. What You Should Know Wheat Stripe Rust Published by Utah State University Extension and Utah Plant Pest Diagnostic Laboratory PLP-002-PR revised January 2008
TL;DR: The main strategies for leaf rust control have been the development and the cultivation of cultivars with genetic resistance and the application of fungicides to above-ground plant parts.
Abstract: Diseases are among the main factors that have limited wheat production in Brazil. Most of the fungal diseases are favored by weather conditions with predominance of high temperature and frequent rainfall (2). Among the main fungal diseases of wheat, leaf rust, caused by Puccinia triticina Eriks, is considered one of the most important crop diseases causing damage of up to 63% (2, 5). The main strategies for leaf rust control have been the development and the cultivation of cultivars with genetic resistance and the application of fungicides to above-ground plant parts (26, 27). The genetic resistance of wheat to P. triticina is not durable due to the high variability of this fungus, resulting in the occurrence of at least one new virulent race in almost each wheat growing season (6). The earliest identification of leaf rust physiologic races in Brazil dates from 1949 and started in the former “Instituto Agronomico do Sul” (IPEAS Pelotas-RS). There are reports of 26 races identified in samples collected from 1949 to 1952, with the use of an international differential set. In the period from 1952 to 1957, using a group of additional cultivars to the international set, 24 P. triticina races were determined (2). Until 2007 growing season, 60 races of the fungus were identified in Brazil (Barcellos & Chaves 2003). In this pathosystem, genetic variability (vertical resistant genes) is well known for the host and the fungus concerning virulence (2, 3, 7, 8, 24).
TL;DR: Crop loss assessment at different fungicide spray schedule revealed that there was significant reduction in yield when disease severity was more than 50%.
Abstract: A field experiment was carried out in deep black soil at Main Agricultural Research Station, College of Agriculture, University of Agricultural Sciences, Dharwad, Karnataka during kharif 2010, under rain-fed condition The yield losses due to common rust were found directly related to disease severity The avoidable yield losses due to disease were in the range of 1175 to 6053% in different spray schedule Crop loss assessment at different fungicide spray schedule revealed that there was significant reduction in yield when disease severity was more than 50% Six sprays of the Hexaconazole at 01% completely controlled the disease and contributed to increased yield
Key words: Maize, common rust, Puccinia sorghi, yield loss
Patent•
02 May 2012
TL;DR: In this paper, an organic composite reinforced concrete rust inhibitor and a preparation method of its preparation is presented. But the method is not suitable for the use in concrete, as it requires a large amount of water.
Abstract: The invention discloses an organic composite reinforced concrete rust inhibitor and a preparation method thereof. According to the invention, the rust inhibitor is prepared from well-mixed materials of, by weight: 30-40% of alcohol amine carboxylate, 5-10% of sodium monofluorophosphate, 0.1-0.5% of an anionic surfactant, and balance of water. The rust inhibitor has a good diffusion performance inconcrete, and can simultaneously acts upon the cathodes and the anodes of steel bars. The trust inhibitor forms stable chelate rings with the steel bars, and has an excellent rust inhibiting performance. Also, the anions in the rust inhibitor can be combined with calcium ions in the concrete, such that precipitates are formed. With the precipitates, capillary pores in the concrete can be obstructed, and the chloride ion penetration resistance of the concrete can be improved.
TL;DR: The aims of the present research were to characterize bean rust isolates collected from snap bean growing areas in Kenya and to identify which of the available rust resistance genes in common bean differentials are most effective to control rust in those areas.
Abstract: Bean rust (Uromyces appendiculatus (Pers.:Pers.) Unger var. appendiculatus) is one of the most devastating and variable pathogens of common bean (Phaseolus vulgaris L.) worldwide that can cause total crop loss. Characterization of bean rust races can help in screening resistant materials during gene pyramiding. The aims of the present research were first, to characterize bean rust isolates collected from snap bean growing areas in Kenya. Secondly, to identify which of the available rust resistance genes in common bean differentials are most effective to control rust in those areas. Snap bean leaf tissues with rust pustules were collected from different farms in eight locations in central and western Kenya during the years 2010 and 2011. Forty seven single pustule isolates were obtained and inoculated on 12 bean rust differential cultivars. For consistent results, the inoculation was repeated twice. The new international classification system and the binary nomenclature grouped the 47 single pustule isolates of U. appendiculatus into 9 different races, most of this affected the Andean gene pool. Hierarchical cluster analysis grouped the races into two major clusters depending on the virulence of the races on the host differential cultivars. The most resistant genes for pyramiding in Kenya were identified as Ur-5, Ur-11 and Ur-CNC. An important output of this study was the identification of races with potential use during gene pyramiding process.
Key words: Uromyces appendiculatus, snap bean, races, genes, characterization.
TL;DR: In this paper, the mechanical properties, corrosion resistance and microstructures of high performance steel (HPS) were investigated by tensile testing machine, Charpy V-Notch (CVN) testing machines, cyclic immersion corrosion tester, XRD, optical microscopy (OM), scanning electron microscopy, and electron probe micro-analyzer (EPMA).
Abstract: The mechanical properties, corrosion resistance and microstructures of high performance steel (HPS) was investigated by tensile testing machine, Charpy V-Notch (CVN) testing machine, cyclic immersion corrosion tester, XRD, optical microscopy (OM), scanning electron microscopy (SEM), and electron probe micro-analyzer (EPMA). The results showed that significant differences existed in the tensile strength, yield strength and impact toughness between HPS and PCS. After 72 h cyclic immersion accelerated corrosion test, the inner rust layer on HPS was composed of α-FeOOH phase and denser than that on PCS that was a mixture of α-FeOOH and Fe3O4. The rust formed on HPS provides better protection and HPS has lower corrosion rates than PCS. Copper and chromium in HPS enrich in the rust layer and enhance the compactness of the rust layer. Based on the results of the accelerated corrosion tests and rust layer analysis, the roles of Cu and Cr against corrosion are discussed, providing HPS with chemical specification which has been industrially successful to produce weathering steel for bridge structure.