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The narrow genetic base of lentil (Lens culinaris) has challenged the efforts of breeders to increase its productivity under changing environmental conditions. Inclusion of wild species and diverse cultivated genotypes offers an opportunity to generate new variation through wide hybridisation to broaden the genetic base of cultivated lentil. We evaluated 96 elite, interspecific (L. culinaris x L. orientalis) and intraspecific advanced lentil genotypes along with four checks to determine the extent of genetic variation, resistance to lentil rust (Uromyces viciae-fabae), and the nature and magnitude of their genetic divergence. Sufficient genetic variability was revealed for all of the traits. High heritability and genetic advance were recorded for number of seeds per pod, number of pods per plant, seed yield per plant and biomass per plant. A positive correlation was recorded between grain yield and ten important plant traits. Statistical (D²) and molecular analyses grouped all genotypes into two main clusters and revealed sufficient genetic diversity among advanced lines. Our study showed promising results for creating new variation through wide hybridisation and identified lines L-354 and L-437-1 (rust-resistant) and HPLL-32 (moderately rust-resistant) superior for seed yield and related traits. [ABSTRACT FROM AUTHOR]

Uromyces japonicus is an autoecious leaf rust of Allium victorialis sensu lato. The rust forms concentric sori on the adaxial surface of host leaves. This fungus is a potential pathogen for economically important Allium plants. Initially, we observed in planta fungal structures using newly developed whole-leaf fluorescent imaging method to evaluate the rust lesion formation process. We then confirmed conspecificity of Japanese and European populations by comparing the morphological characteristics and rDNA sequences. In addition, we estimated phylogenetic relationships among rust fungi on Allium plants. In this study, we designate an epitype of U. japonicus based on fresh specimens from Japan. [ABSTRACT FROM AUTHOR]

BACKGROUND Rusts are a noxious group of plant diseases affecting major economically important crops. Crop protection is largely based on chemical control. There is a renewed interest in the discovery of natural products as alternatives to synthetic fungicides for control. In this study we tested two fungal metabolites, namely cyclopaldic acid and epi-epoformin, for their effectiveness in reducing early stages of development of two major rust fungi from the genera Puccinia and Uromyces, P. triticina and U. pisi. Spore germination and appressorium formation were assessed on pretreated detached leaves under controlled conditions. Cyclopaldic acid and epi-epoformin were also tested in infected plants in order to evaluate the level of control achieved by treatments both before and after inoculation. RESULTS Cyclopaldic acid and epi-epoformin were strongly effective in inhibiting fungal germination and penetration of both rust species studied. This effect was not dose dependent. These results were further confirmed in planta by spraying the metabolites on plant leaves, which reduced fungal developmental of U. pisi and P. triticina at values comparable with those obtained by application of the fungicide. CONCLUSION Our results further demonstrate the potential of fungal metabolites as natural alternatives to synthetic fungicides for the control of crop pathogens of economic importance as rusts. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Gladiolus rust, caused by Uromyces transversalis, affects foliage and reduces flower quality of Gladiolus spp.; this can lead to severe economic loss because of reduced yields, and even total crop loss. Spatial analysis studies of this disease are fundamental in order to plan strategies to manage crop health, improve sampling methods, and determine both current and potential production losses. The aim of this study was to analyze the spatial distribution of rust using geostatistical techniques in the municipalities of Ocuilan, Tenancingo and Villa Guerrero, in the southeastern region of the State of Mexico, during the spring-summer growing cycles of 2013 and 2014. The severity level of the disease was estimated at 121 georeferenced sampling points within each evaluated area. Gladiolus rust showed an aggregated spatial distribution in the different crop phenological stages during which it expressed throughout the two years of the study. The spatial dependency model was best described by the Gaussian model, followed by the spherical one. [ABSTRACT FROM AUTHOR]

In order to evaluate the antifungal activity of Spathodea aqueous extracts, as a viable alternative for the control of bean rust, this work was realize in an field independent farmer in Corralillo municipality, Villa Clara province, between January and May 2014. For this, aqueous extracts from leaves and flowers were applied at 5 and 10% on BAT-304 bean variety. The experiment was made under a design of random blocks with six treatments and three replications. The extract applications began from 30 days of age (flowering) and the last 65 days, with a frequency of five days. It was objetive determining the infection intensity and rust distribution in each one of the treatments as well as their effect on quantitative variables (number of pustules/ leaf, pustules diameter and yield. As results was found that the aqueous extracts of leaves and flowers of S. campanulata, showed antifungal activity against Uromyces phaseoli applied at 10%. [ABSTRACT FROM AUTHOR]

Background: Photosynthesis is the key process for plant growth and development. The determination of chlorophyll fluorescence kinetics allows the quantification of effects on photosynthetic processes triggered by environmental stress factors such as, e.g., the infection by fungal phytopathogens. The technique is non-invasive, rapid and well suited for experimental field work. Results: Healthy and Uromyces-infected plants of Euphorbia cyparissias were monitored directly in situ in the field using rapid fluorescence kinetics. Non-infected healthy plants show a typical maximum value for the relative variable fluorescence Fv/Fm of around 0.8 with occasional variation between the leaves from the plant top towards the base, while infected plants exhibited a strong gradient to low values at the base. The photosynthetic performance index (PI) showed a higher heterogeneity within the leaves in both plant types. Conclusions: The non-invasive and rapid measurement of chlorophyll fluorescence induction allows characterizing the photosynthetic capacity of healthy and infected plants and of parts of them directly in the field. The PI, is highly sensitive not only concerning infection, but also towards other local environmental influences. [ABSTRACT FROM AUTHOR]

The sexual morph of Aecidium goyazense collected in the Brazilian Cerrado was morphologically characterized by light microscopy and SEM, and shown to be a species of Uromyces, for which the name Uromyces hawksworthii nom. nov. is introduced, and designated as its epitype. This is the second Uromyces species known to infect the tropical genus Phthirusa (Loranthaceae). DNA sequences were generated from the ITS and 28S rRNA (LSU) regions of DNA recovered from aeciospores as well as teliospores. This fungus is compared with other Uromyces species known from Loranthaceae. [ABSTRACT FROM AUTHOR]

Mucormycosis is an uncommon infectious complication after renal transplantation and is associated with fatal outcomes. We report 2 cases of transplant renal artery thrombosis and spontaneous rupture caused by mucormycosis. As stenosis, thrombosis, and spontaneous rupture of the transplant renal artery began to occur in both cases after renal transplantation, nephrectomy of the transplanted kidney was performed. Postoperative pathological findings in the transplanted kidney revealed an invasive mucormycosis infection in the renal artery. One patient survived, but the other patient died. This report also presents the diagnosis and treatment processes used for this transplant complication. [ABSTRACT FROM AUTHOR]

Information about slow rusting resistance to pea rust (Uromyces fabae) is limited. Five slow rusting components, i.e. area under disease progress curve (AUDPC), latent period (LP), number of pustules per leaf (NPL), pustule size (PS), number of aecial cups (NAC) and sensitivity of leaf to rust (SLR), were evaluated in 38 pea genotypes under field conditions. Estimates of correlation coefficients indicated a high negative association of LP with AUDPC (r = -0.751; P ≤ 0.001), NLP (r = -0.808; P ≤ 0.001), PS (r = -0.458; P ≤ 0.001) and NAC (r = -0.476; P ≤ 0.001). However, significant positive association was found between AUDPC and NPL (r = 0.78; P ≤ 0.001), PS and NAC (r = 0.545; P ≤ 0.001). Factor analysis showed that, three of the slow rusting components, i.e. AUDPC, LP and NPL accounted for 49.77% of the total variance as the first main factor, while the other three traits distributed within the next two factors determined 26.34% and 10.46% of the total variance, respectively. A multiple regression analysis showed that the variation in AUDPC was significantly explained by number of pustules followed by latent period. Selection for slow rusting could be based on one component since they are interdependent but, for accumulating more partial resistance in a line, selection should be based on more than one component studied. [ABSTRACT FROM AUTHOR]

Background Grass pea (Lathyrus sativus L.) is a valuable resource for potentially durable partial resistance to rust. To gain insight into the resistance mechanism and identify potential resistance genes, we generated the first comprehensive transcriptome assemblies from control and Uromyces pisi inoculated leafs of a susceptible and a partially rust-resistant grass pea genotype by RNA-seq. Results 134,914 contigs, shared by both libraries, were used to analyse their differential expression in response to rust infection. Functional annotation grouped 60.4% of the contigs present in plant databases (37.8% of total) to 33 main functional categories, being "protein", "RNA", "signalling", "transport" and "stress" the most represented. Transcription profiles revealed considerable differences in regulation of major phytohormone signalling pathways: whereas Salicylic and Abscisic Acid pathways were up-regulated in the resistant genotype, Jasmonate and Ethylene pathways were down-regulated in the susceptible one. As potential Resistance-genes we identified a mildew resistance locus O (MLO)-like gene, and MLO-related transcripts. Also, several pathogenesis-related genes were up-regulated in the resistant and exclusively down regulated in the susceptible genotype. Pathogen effectors identified in both inoculated libraries, as e.g. the rust Rtp1 transcript, may be responsible for the down-regulation of defence-related transcripts. The two genotypes contained 4,892 polymorphic contigs with SNPs unevenly distributed between different functional categories. Protein degradation (29.7%) and signalling receptor kinases (8.2%) were the most diverged, illustrating evolutionary adaptation of grass pea to the host/pathogens arms race. Conclusions The vast array of novel, resistance-related genomic information we present here provides a highly valuable resource for future smart breeding approaches in this hitherto under-researched, valuable legume crop. [ABSTRACT FROM AUTHOR]

Uromyces fabae is a major pathogen of broad bean, Vicia faba. U. fabae has served as a model among rust fungi to elucidate the development of infection structures, expression and secretion of cell wall degrading enzymes and gene expression. Using U. fabae, enormous progress was made regarding nutrient uptake and metabolism and in the search for secreted proteins and effectors. Here, we present results from a genome survey of U. fabae. Paired end Illumina sequencing provided 53 Gb of data. An assembly gave 59,735 scaffolds with a total length of 216 Mb. K-mer analysis estimated the genome size to be 329 Mb. Of a representative set of 23,153 predicted proteins we could annotate 10,209, and predict 599 secreted proteins. Clustering of the protein set indicates families of highly likely effectors. We also found new homologs of RTP1p, a prototype rust effector. The U. fabae genome will be an important resource for comparative analyses with U. appendiculatus and P. pachyrhizi and provide information regarding the phylogenetic relationship of the genus Uromyces with respect to other rust fungi already sequenced, namely Puccinia graminis f. sp. tritici, P. striiformis f. sp. tritici, Melampsora lini, and Melampsora larici-populina. [ABSTRACT FROM AUTHOR]

A collection of 267 accessions belonging to 61 Vicia species other than V. faba was screened under growth chamber conditions for response to Ascochyta fabae and Uromyces viciae-fabae, causal agents of ascochyta blight and faba bean rust, respectively. High resistance to both diseases was very frequently detected in Vicia spp. in contrast to the high susceptibility previously reported in most V. faba accessions. Most of the Vicia spp. accessions studied here were very resistant or even immune to A. fabae with only one per cent of the accessions allowing development of small lesions bearing pycnidia. High resistance or immunity to U. viciae-fabae was also frequently found in the collection, with only ten per cent of the accessions showing compatible interaction although with reduced disease severity. These findings reinforce the specificity of A. fabae and U. viciae-fabae and clarify the potential role of cultivated and wild Vicia spp. in the epidemiology of these faba bean diseases. [ABSTRACT FROM AUTHOR]

It was evaluated the reaction of twenty-five common bean varieties to Uromyces phaseoli (Pers.) Wint var. typica Arth infection using the methodology informed by the Colombian International Center of Tropical Agriculture (CIAT). These experiments were developed in the Agricultural Experimental Station belonging to the Agricultural Sciences Faculty of Las Villas Central University, under a design of random blocks with four repetitions in the period between January to April 2011. The evaluations of infection intensity and pustule type were carried out weekly starting from the beginning of disease symptoms in 15 plants for varieties. Results evidenced differences in the response of varieties as well as a different behavior to the infection for this phytopathogen fungus. Guama 23 variety was classified as resistant highly to the infection for U. phaseoli. This work constitutes a fundamental tool for future programs on genetic improvement of common bean cultivation in Cuba. [ABSTRACT FROM AUTHOR]

Lentil ( Lens culinaris Medik.) is an important cool-season legume that can be severely damaged by rust ( Uromyces viciae-fabae (Pers.) Schröt.) in many parts of the world. In this work, a collection of L. culinaris germplasm accessions was screened under growth chamber conditions for response to U. viciae-fabae. Several sources of incomplete resistance have been identified, both of hypersensitive and of non-hypersensitive nature. Incomplete hypersensitive resistance was due to a late-acting host cell necrosis that resulted in an intermediate infection type ( IT). Incomplete non-hypersensitive resistance was due to a hampered cell penetration not associated with host cell necrosis, reducing the number of haustoria per colony and therefore hindering the growth of the colony and reducing and retarding disease development in spite of a high IT. [ABSTRACT FROM AUTHOR]

Chickpea rust (Uromyces ciceris-arietini (Grognot) Jacz. & Boyd.) is an important foliar disease in all areas where this legume is cultivated. The present work was carried out during two consecutive years (2009 and 2010), with the objective of evaluating, under field conditions, the incidence (I) and severity (S) of chickpea rust on 28 genotypes and its relationship with leaf types (TH) uni-imparipinnate (A) and multipinnate (B). In the time studied, rust manifested massively late, with I = 92.14 % and S = 61.10 %, corresponding the highest infection levels to genotypes with leaf type A, compared to leaf type B; three lines B and one A presented better behavior to rust. Severity and incidence was correlated with each other and with the TH. This work constitutes the first study carried out in Cuba about genotypes response to rust and represents an advance step in the genetic improvement related with the selection, adoption and dissemination of chickpea cultivars with a better disease behavior. [ABSTRACT FROM AUTHOR]

The investigations on the rust fungus Uromyces geranii (DC.) Lev. influence on the anatomy of the vegetative organs of the host plant Geranium sanguineum L. (Geraniaceae) were conducted. The local and endophytic arrangement of U. geranii in the tissues of the host plant were identified. The tissues hypertrophy and organs deformation in G. sanguineum were revealed as a consequences of the fungus U. geranii influence as well as increment of pericyclic ring sclerenchyma lignification in the stem. While the mature aecia and uredinia on the stem cause the epidermis tears and fill the primary cortex up to the stele. [ABSTRACT FROM AUTHOR]

Abstracts: The genus Vicia includes many species of agricultural interest, such as faba bean and the various vetches that may be infected by rust, with little understanding of the specificity of these interactions. This work contributes to the clarification of host range of Uromyces viciae-fabae and Uromyces pisi, and confirms host specialization within U. viciae-fabae. The differential response of Vicia faba, Vicia sativa and Lens culinaris checks confirms the existence of specialized isolates of U. viciae-fabae. Host range of these host specialized forms of U. viciae-fabae was not so clear cut when we test other species of Vicia. The most specialized form was U. viciae-fabae ex V. faba that was able to infect profusely only faba bean (V. faba), all other Vicia species being highly resistant. Conversely, susceptibility against U. viciae-fabae ex V. sativa was very common in Vicia spp., particularly in those belonging to the subgenus Vicia, although not in V. faba. Still, susceptibility could be identified in a number of accessions of section Cracca such as Vicia cracca, Vicia monantha, Vicia sicula or Vicia villosa. Most Vicia accessions were highly resistant to U. viciae-fabae ex L. culinaris, but a number of accessions could be severely rusted, particularly in species of the subgenus Vicilla but also in some of section Peregrinae of subgenus Vicia. Similarly, most Vicia accessions were highly resistant to U. pisi but a number of accessions could be severely rusted, particularly in species of the subgenus Vicilla and in sections Hypechusa and Peregrinae of subgenus Vicia. This work also identified sources of resistance to the various rusts that can be used in rust resistance breeding. In spite of the susceptibility against various rusts, interesting levels of resistance were identified in crops and related species being based either on hypersensitive response or on reduced severity in spite of a compatible interaction making resistance breeding feasible. [Copyright &y& Elsevier]

Abstract: Systemic acquired resistance (SAR) to Uromyces pisi in pea was studied by using a proteomic approach. Two-dimensional electrophoresis (2-DE) was used in order to compare the leaf proteome of two pea genotypes displaying different phenotypes (susceptible and partial resistance to the fungus), and in response to parasite infection under the effect of two inducers of SAR, BTH and BABA. Multivariate statistical analysis identified 126 differential protein spots under the experimental conditions (genotypes/treatments). All of these 126 protein spots were subjected to MALDI-TOF/TOF mass spectrometry to deduce their possible functions. A total of 50 proteins were identified using a combination of peptide mass fingerprinting (PMF) and MSMS fragmentation. Most of the identified proteins corresponded to enzymes belonging to photosynthesis, metabolism, biosynthesis, binding and defense response, whose behavior pattern was different in relation to susceptibility/resistance of the genotypes studied and to the BTH/BABA induction to pathogen response. Results obtained in this work suggested that plants could reduce their photosynthesis and other energy metabolism and enhance the production of defense-related proteins to cope the stress. On the other side, we postulated that resistance induced by the chemicals operates via different mechanisms: BABA inducer could act via phenolic biosynthesis pathway, whereas resistance provided by BTH inducer seems to be mediated by defense and stress-related proteins. The results are discussed in terms of response to rust under the effect of inducers. [Copyright &y& Elsevier]

Abstract: Rust is a serious disease of pea whose casual agent is not always understood. In this paper we studied reaction of pea accessions to seven rust species infecting closely related legumes, finding that indeed pea can be infected mainly by Uromyces pisi, followed by Uromyces viciae-fabae. Other rust species like Uromyces striatus, Uromyces ciceris-arietini, Uromyces anthyllidis and Uromyces vignae can also infect and reproduce on pea, although in a minor extent. All U. pisi isolates tested were very virulent on pea accessions, but isolates UpPt-03 and UpKeS-05 (from Palmar de Troya, Spain and Kafr-El-Sheik, Egypt respectively) were significantly most infective. In addition to this we studied in detail the host range of U. pisi by inoculating multiple accessions of various legumes with urediospores of seven isolates of U. pisi from different geographical origins. Both experiments were performed under controlled conditions. Based on the evidence presented here the host range of U. pisi is greater than previously recorded, including genotypes belonging to Cicer arietinum, Vicia articulada, Vicia ervilia and Vicia faba, which were not mentioned before. [Copyright &y& Elsevier]