In order to investigate the host range of various populations of causal agent of wheat leaf rust, Puccinia. recondita sensu lato, during 2010-2016, fifty isolates of the pathogen were collected from different hosts of Poaceae in various parts of Iran including: Ardabil, Fars, Golestan, Ilam, Kerman, Khuzestan, Khorasan Razavi, Kurdistan, Mazandaran and West Azerbaijan. Pathogenicity of all isolates on seven hosts, including bread wheat (Triticum aestivum L., cv. Boolani), durum wheat (Triticum durum Desf., cv. Karkhe & cv. Yavaroos), barley (Hordeum vulgare L., cv. Afzal), oat (Avena sativa L.), rye (Secale montanum Guss.) and triticale (Triticosecale Wittm. Ex A. Camus) was examined. Results indicated that all isolates had high disease severity on bread wheat (cv. Boolani) and triticale. Bread wheat isolates were avirulent on all hosts except for triticale, which showed a hypersensitive reaction or small, dispersed pustules. Triticale isolates were only pathogenic on triticale and bread wheat. Durum wheat isolates were virulent on bread wheat, durum wheat, and triticale, and were avirulent on barley and rye plants. Oat isolates showed an avirulence response on barley, rye and various genotypes of durum wheat and rye. Barley isolates were also pathogenic on bread wheat, triticale and barley and avirulent on durum wheat and rye. Although wild barley isolates were virulent on bread wheat, durum wheat, and triticale, they were avirulent on other hosts. Oat is a non-host for all leaf rust isolates, except for its own isolates. The findings indicate that in the absence of wheat, leaf rust populations are able to survive on other members of the Poaceae family.

The barley leaf rust has been important in recent years in Iran. In order to identify the genetic resources of resistance to this disease, 207 Iranian barley landraces were studied. The germplasms were investigated at the field of Iraqi-Mahalleh research station in Gorgan as the disease hotspot under natural incidence over three years. The results showed that four genotypes including KC18638 and KC18643 from Golestan and KC19087 and KC 19093 from Gilan expressed immunity response in all three years of the experiment and 31 accessions were immune in two years. The results of principal component analysis in three years showed that 90.69% of the variations in the data were justified by the first three principal components. The results of this study indicated the possibility of racial variation in the studied disease hotspot. These findings show the importance of tracing the changes in the disease hotspot which is necessary for planning, breeding and cultivation of cultivars with effective resistance. Also, the resistant genotypes identified in this research can be used as genetic resources of leaf rust resistance in breeding programs.

In this research, the interaction between two biocontrol strains of Pseudomonas fluorescens (PF153mcherry andCHA0gfp2)and three wheat cultivars (Boulani, Roushan, Forno) were studied to control wheat leaf rust disease (Puccinia triticina) under greenhouse conditions. Bacteria were appliedusing the seed treatment method. Results showed a reduction in disease severity on the leaves in certain combinations of bacterial strains and wheat cultivars. This was particularly evident for the interaction between CHA0gfp2 and Forno with 69.74% decrease in the number of pustules on leaves. The Bolani and Forno cultivars that were not treated by bacteria exhibited the highest infection of leaf rust. Study of bacteria–wheat-pathogen interactions showed that the interaction between PF153mcherry with infected and non-infected Forno showed the highest bacterial colonization (7801.1 and 8154.4 cfu per mg dry root, respectively). Interaction between CHA0gfp2 with infected and non-infected Roushan cultivar induced the lowest colonization on the rhizosphere by 938.2 and 887.3 cfu per mg dry root, respectively. However, interaction between pathogen and cultivars resulted in the increase of peroxidase and phenylalanine ammonia lyase (PAL) activity in the leaves. In summary, we observed negative correlations between the bacterial colonization (cfu per mg dry root) and the number of rust pustules on the leaves. There was significant correlation between PAL activity and disease severity. Overall results of this study indicate that there is a promising beneficial interaction between the bacterial isolates and wheat cultivars which induce systemic resistance and suppress the leaf diseases in the sustainable agricultural system.

The interaction between root-colonizing Pseudomonas fluorescens strain CHA0mcherry and three wheat cultivars (Bolani, Roushan, Forno) was studied as a phenomenon to be employed in the control of Wheat Leaf Rust Disease (Puccinia triticina). CHA0mcherry was inoculated using seed treatment method. The application of CHA0mcherry reduced the number of pustules on leaves via inducing systemic resistance, specially in Bolani cultivar. The non-inoculated Bolani and Forno cultivars exhibited the highest infection of the leaf rust. A study of the bacteria-wheat-pathogen interaction indicated that Forno was the most responsive root- colonized variety to the bacterium. The lowest colonization was observed within the rhizosphere of Roushan cultivar. Interaction between pathogen and cultivars was shown to lead to increase of peroxidase and Phenylalanine Ammonia Lyase (PAL) activity in leaves. In summary, the results showed negative correlations between the bacterial colonization (cfu per mg dry root) and the number of rust pustules on the leaves. There was also a significant correlation noted between PAL activity and disease severity.

In this study, the first symptom appearance of wheat leaf rust disease was monitored in Khuzestan Province every ten days from early December 2014, for three years. Also, the climate changes and their influence on the development of the disease were studied. During 2014-2015, the first symptoms, with the severity of 5 MS (Moderately Susceptible), appeared in the south and west parts in early and mid-March, respectively. In northern areas, the symptoms appeared with 10 MS severity in early May. In 2015-2016, the first symptoms appeared with the severity of 5 MS in February in the southern areas. In the west, symptoms appeared and reached 20 S (susceptible) on March 10. In the north, the disease started in late February with the severity of 10 MS and developed to 30 S. In 2016-2017, the first symptoms appeared around the Karun River with the severity of 5 MS on March 10 and eventually reached 10 MS in late March. In the western areas, the disease started in early March with the severity of 5 MS and then stopped. Symptoms appeared one week later in the north, with the severity of 5 MS, and reached 15 MS until the end of March. Based on the previous studies, the first symptoms of wheat leaf rust usually start from the west. However, now, the regional pattern of the symptom has changed dramatically, and it appears in the south near Karun River and the Sugar Cane Crop Industry. This might be due to implementation of preventive measures and dryness of a big part of Hoveyzeh Marshland.

Identifying resistance related metabolites as biomarker for screening wheat germplasms resistant to leaf rust (Puccinia triticina) is a useful approach to increase the speed, accuracy and cost effectiveness of screening disease resistance. The relatively polar metabolites were extracted in a mixture of methanol-water from near isogenic line (NILs) of wheat susceptible (Thatcher Lr22b) or resistant (Thatcher Lr25) to leaf rust in the two leaf stage, 24 h after inoculation with the pathogen, talcum powder or sterilized distilled water, in three replications. Metabolites were analyzed using a GC/MS. ANOVA showed that abundance of 26 metabolites had significant differences among experimental factors including near isogenic lines (NILs), inoculation (I) and NILs ×I interaction. Abundance of 26 significant metabolites was subjected to canonical discriminant analysis and hierarchical cluster analysis to group observations of metabolite profiles based on similarities and differences in the investigated metabolic space. Finally 13 resistance related metabolites (RR) and 13 Pathogenesis related metabolites (PR) were identified that the majority of RR metabolites involved in induced resistance and constitutive resistance. Significant metabolites included metabolites with potential signaling and/or antimicrobial activity as well as molecules used as precursors for cell wall reinforcement, phenolic and alkaloids compounds, and accumulation of amino acids and proteins associated with resistance. Up-regulation of the number pathways upon infection of wheat to leaf rust fungus is discussed.Key words: metabolic profiling, Wheat leaf rust, screening resistance, gas chromatography/mass spectrometry.

Puccinia recondite (Leaf rust) is an endemic disease in Iran; this disease can affect the productivity and quality of wheat, that occurring in all wheat growing regions. Genetic resistance to leaf rust of wheat is the most important strategy to control the diseases and 51 leaf rust resistance genes (Lr gene) are reported in wheat to provide resistance to leaf rust. This study aims to identify presence or absence of leaf rust resistance gene Lr32 in 48 Iranian wheat cultivars and lines using of infection-type data test and molecular markers linked to the leaf rust resistance gene. Infection-type analysis based on international method of Browder (1973) with 6 leaf rust pathotype known in Iran, revealed that, first, 17 out of 48 cultivars and lines have effective resistance to race virulence of leaf rust gene Lr32, second, 25 cultivars and lines foresight probability presence resistance gene Lr32 or genes with similar effect, and at last, absence of leaf rust resistance gene Lr32 revealed in 6 cultivars and lines. In molecular part, using known RAPD molecular markers (S49 and S421), evaluated possibility of present of 1100 bp and 640 bp fragments that closely linked to leaf rust resistance gene Lr32 in 48 wheat cultivars and lines. In according with expectation, detected 1100 bp and 640 bp fragments in near-isogonic's Lr gene but none of cultivars, lines and negative control line (Bolani and Agra Local), showed amplification related resistance gene fragments. Result of molecular Markers and infection-type data test showed absence of leaf rust resistance gene Lr32 in 48 Iranian wheat cultivars and lines.

Brown rust or leaf rust of wheat caused by Puccinia triticina Eriks. It is considered one of the most damaging diseases of wheat all over the world, including Iran. Brown rust can reduce the yield of wheat in fields by 20 to 50% in epidemic conditions. The fungus that causes brown rust disease due to having a sexual cycle and new genetic recombinations resulting from it (presence of intermediate hosts in most regions), an asexual cycle in favorable weather conditions and Also, the probability of occurrence of phenomena such as mutation, migration and selection pressure by resistance genes in the hosts has high genetic diversity (variety of physiological breeds), genetic flexibility (variability) which by producing new breeds with Completely different pest patterns can overcome the created genetic resistance. The newly created breeds can be quickly transferred from one area to another through the wind and cause an increase in racial diversity in the disease population of other areas. The most reliable and fundamental method of its control and management is the use of genetic resistance. Accurate knowledge of the genetic structure of the pathogenic population in each region is the first step and road map to achieve effective and stable genetic resistance in wheat. This is possible through the monitoring of harmful pathogenic factors on the differential genotypes of brown rust in the trap vaults.

The effectiveness of resistance genes of international differential cultivars of brown rust was investigated in Moghan region of Ardabil province as one of the important poles of Iranian wheat production in two consecutive crop years (2022-2023). To identify the sources of resistance to the existing breeds in the region, the responses of 40 commercial varieties and 40 promising lines of wheat was evaluated. Investigating the resistance response in the full plant stage under natural pollution conditions, by the parameters of pollution coefficient (CI), final disease severity (FDS) and the relative value of the area under the disease progression curve (rAUDPC) in the research station of the Research and Training Center for Agriculture and Natural Resources of Ardabil Province (Moghan) were measured.

The population of breeds in Moghan region were different from each other in both years. The results indicated that in both years of the test, the pathogenic mushroom population had immunity to differential cultivars carrying resistance genes Lr18, Lr19, Lr20, Lr22a, and Lr29. Therefore, these genes have the necessary efficiency to create effective resistance to brown rust pathogenic races in Moghan region. The differential cultivars carrying the resistance genes Lr2a, Lr2b, Lr9, Lr17, Lr21, Lr23, Lr10/Lr27/Lr31, Lr33, and Lr34 also showed relatively acceptable resistance to the pathogenic strains of brown rust in Ardabil region. The reaction of the genotypes carrying these genes was specific to the race. In other words, in one year they had a resistance reaction and in another year they had a semi-resistant to semi-sensitive reaction with an intensity of 5-20% contamination. Commercial cultivars and promising lines of wheat, which had an effective resistance response and the lowest value for the measured traits, as sources of effective genetic resistance to the brown rust pathogenic population in Moghan region and similar regions in The hot and humid climates of the country are introduced, which include Sahar, Rakhshan, Shush, Farin, Sirvan, Araz, Meraj, Danesh, Talai, Sana, Aran, Tirgan, Taban, Hana, Mehrgan, Avan, Arman, Fallah, Tektaz cultivars. and lines N-95-6, N-98-8, S-95-3, S-96-15, S-96-16, S-97-10, S-98-11, S-98- 22, M-97-12, M-97-18, M-98-18, CD-91-12, C-97-4, CD-97-19, C-98-7, C-98-8, They were CD-98-17, MS-92-5, MS-94-5, D-97-15, and D-97-16.

Correct and conscious use of the combination of effective resistance genes identified in this research can create more stable resistance to brown rust. It is possible to use the resistance genes present in resistant genotypes identified in multi-breeding programs for the pyramiding of resistance genes in desirable wheat genotypes in terms of agricultural traits, yield and other physiological characteristics, in the production of stable resistant cultivars. Compared to the disease, he used a brown rust.

Wheat leaf rust (Puccinia triticina Eriksoon) is of the most injurious wheat diseases that prevails throughout areas where wheat is grown. An identification of virulence factors along with differences in the population of pathogen in different wheat growing regions is necessary for an enhancement of resistant cultivars with effective resistant genes to leaf rust. To accomplish the purpose, a leaf rust Trap Nursery containing 37 near isogenic lines in addition to Bolani susceptible cultivar as check were planted under natural infection conditions in Gorgan (with an application of mist irrigation) and Gonabad (with no mist irrigation) locations during 2002-2007. Reaction to the disease of each line was recorded at the flag leaf stage and when infection on the Bolani susceptible cultivar was at its maximum level for infection rate and type. "S" reaction indicated virulence while "O, R, MR and MS" reactions were indicative of as avirulence. Results showed that virulence was detected for genes Lr1, Lr2c, Lr3, Lr3ka, Lr3bg, Lr10, Lr11, Lr12, Lr13, Lr14a, Lr14b, Lr15, Lr16, Lr17, Lr18, Lr20, Lr21, Lr22a, Lr22b, Lr23, Lr24, Lr26, Lr30, Lr32, Lr33, Lr34 and either Lrb at one or both Gorgan and Gonbad locations. Virulence was observed for genes Lr3, Lr10, Lr14b, Lr17, Lr18, Lr26 and Lr34 only at Gorgan site. No virulence was observed for genes Lr2a, Lr2b, Lr19, Lr25, Lr28, Lr29, Lr35, Lr36 and Lr37 at these locations. Avirulence due to the resistance of the above resistant genes provides the possibility of the use of these genes in breeding programs to develop varieties resistant to wheat leaf rust.

Leaf (brown) rust, caused in wheat by the fungus Puccinia triticina is an important disease in north, west and south of Iran. Leaf rust is an endemic disease in Iran, which apperas in many parts of the country annually. Use of resistant cultivar is the best way to control this disease. To find resistant sources to the pathogen and use in the breeding program, it is necessary to determine virulence factors of the pathogen. In the present study, 12 locations were allocated in different parts of Iran to study virulence factors of the pathogen in trap nurseries with 37 leaf rust near isogeneic lines and a susceptible cultivar Bolani. Each line was sown in two rows of 1 meter length. The nurseries were maintained under natural infection of the pathogen. Reaction of each line was recorded at the time when infection on the susceptible control was at the maximum level, and presence of virulence for different resistance genes was determind. Results indicated presence of virulence for genes Lr1, Lr2b, Lr2c, Lr3, Lr3ka, Lr3bg, Lr10, Lr11, Lr12, Lr13, Lr14a, Lr14b, Lr15, Lr16, Lr17, Lr20, Lr21, Lr22a, Lr22b, Lr23, Lr24, Lr26, Lr30, Lr32, Lr33 and Lrb. No virulence was detected for Lr9, Lr18, Lr19, Lr25, Lr28, Lr29, Lr34, Lr35, Lr36 and Lr37 genes. Use of these genes with combination of adult plant resistance genes is expectd to be a useful method to control of leaf rust disease.