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.

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.

Leaf rust caused by Puccinia triticina Eriksson is a major foliar disease of wheat, resulting in yield loss all over the world. In order to study the resistance components to leaf rust, a collection of 31 wheat cultivars was screened under controlled conditions at seedling stage inoculated with an isolate (race CHHLS) which had been collected from Lorestan province in complete randomized block design with 3 replications. Latent period was determined by the number of days after inoculation to the appearance of first pustule on the leaf 8 days after inoculation started and continued until 12 days after inoculation. Infection types on primary leaves were rated 12 days after inoculation using the Roelfs method in a scale of 0-4. The cultivar Orom, showed the lowest infection type, the longest latent period however, the cultivar Bolani had the shortest latent period and the highest infection type. Analysis of variance showed that there was a significant difference for infection type, but not for latent period among cultivars. There was a strong negative correlation (r= - 0.6463) between infection type and latent period. Cluster analysis based on ward’s method, categorized the cultivars into three groups as Resistant (Khazar1, Golestan, BKRB, Bam, Neyshabour, BKRZ, Hirmand and Oroum), Moderately Resistant (Sistan, Kavir, Parsi, Navid, Moghan1, Moghan2, Mahdavi, Aflak, Mihan, Alamout, Bahar, Darab2, Shiraz, Chanab, Alborz and Falat) and Susceptible (Zare, moghan3, Atrak, Zarin, Arg, Arvand and Bolani).

Leaf rust of wheat caused by Puccinia triticina Eriksson occurs annually in different parts of Iran. Samples of Puccinia triticina were collected from rust-infected wheat leaves from different regions of Iran during 2007-2008 cropping seasons. Fifty one isolates were collected from different parts of Iran. Purification, inoculation and multiplication of isolates were conducted at the seedling stage of susceptible Bolani, under green house conditions. After inoculation on the seedlings of brown rust of wheat near isogenic lines, a total of fifty one pathotype were identified based on Avirulenve/Virulence formula. In two years some collected isolates showed similar virulence phenotypes included: TKTT, PKTT, PJTT, PHRR, PKRT, PHRT, PGTT and TCTT and the others were unique. Marivan I and Avaz II isolates showed the most virulence and Gorgan II was the least virulence in 2007. In 2008, Borojerd I and Ardebil I showed the more aggressive and Ahvaz II was the least. Among all the collected isolates during two years no virulence were detected on plants with Lr9, Lr19, Lr25 and Lr28 resistance genes. Eight and six clusters were identified based on drawn denderogram at 0.76 cutting line in 2007 and 2008, respectively.

Annual survey for monitoring of reaction of commercial wheat cultivars to stripe rust disease is very important after their introduction and extensive cultivation. The host materials surveyed included the standard differential cultivars for stripe rust along with 24 and three respectively commercial bread and durum wheat cultivars. This study was accomplished in selected wheat fields of six regions of Fars province including Zarghan, Marvdashat, Fassa, Mammassani, Darab and Eghlid during 2003- 2005 and in two stripe rust nurseries in Zarghan and Mammassani during 2003- 2013. The results showed that the resistance of 12 cultivars including Chamran, Shirodi, Shiraz, Darab 2, Falat, Star, kavir, Zarin, Shahriar, Alvand, Alemot and Bahar was overcome by stripe rust during or before the last decade. Yavarous and several recently introduced cultivars including Zareh, Mihan, Siravan, Chamran 2, Ophogh, Behrang and Shabrang have conferred moderately to intermediate resistance reaction to the disease. The cultivars Sivand, Parsi, Pishgham, Marvdasht and Aflak showed a range of moderately resistance to moderately susceptible reaction. The response of Pishtaz varied from moderately susceptible to resistance. Nicknejad has shown to have high level of resistance since its long time introduction. Decrease or changes in the resistance of some of the cultivars can be attributed to changes in stripe rust races, weather conditions and environmental factors. In this regard among the differential cultivars, virulence was almost present for Yr2, Yr6, Yr7, Yr9, Yr17, Yr25, Yr26, Yr27, YrA and YrSU. Current research indicates that annual survey on responses of commercial wheat cultivars to stripe rust together with monitoring of pathogen virulence factors in Fars province are very necessary. These information not only can effectively aid in giving on-time warning to replace susceptible cultivars and to use effective control measures to reduce the loss of the disease, but also can play an important role in short and long time wheat breeding programs.

Wheat rusts including stripe and stem rusts are the most important fungal diseases in the world and Iran as frequently causes natural epidemics and significant yield loses due to rapid development of new races in life cycle resulted from mutation or sexual recombination. In this research, distribution and genetic diversity of aecial infection on barberry bushes and their relation to wheat yellow rust was studied. A total of 95 samples of infected leaves to aecial stage on barberry bushes were collected from Borujerd, Dorud, Azna and Aligudarz regions. To identify the rust species, in vivo and in vitro pathogenicity test were conducted by artificial inoculation of wheat seedlings using collected aeciospores from each region.The results showed the production of urediniospores of P. striiformis f. sp. tritici (yellow rust) as well as P. graminis f. sp. tritici (black rust) in inoculated wheat seedlings. Molecular detection and sequencing of the rDNA regions of representative aecial isolates on Barberry were done. Genetic diversity of 134 aecial isolates was also studied by amplification of IGS1-rDNA region. The Results also confirmed the pathogenicity test and showed that barberry could be the aecial host of yellow and black rusts in Lorestan province. The IGS-rDNA amplification of aecial isolates from Azna and Aligudarz showed most a production of three bands with a frequency of 15 and 21 isolates respectively. In Dorud samples was with five bands (26 isolates) as well as in Broujerd samples with two bands (10 isolates) in which showed a genetic variation among aecial isolates collected from sampling regions in Lorestan province.

In this investigation faba rust Uromyces viciae-fabae was studied for its host range and spore morphology. Three Viciae faba cultivars (Barekat, Saraziry, Shakh Bozi) and four Pisum sativum cultivars (Green Agro- Atrilo- Dorango- Mr. Big) comonly grown in Iran were inoculated with urediniospores produced from a single pustule isolate collected from Shushtar and increased on faba bean in the greenhouse. Disease symptoms were recorded 12 days after inoculation. Infection type of the entries, recorded according to Stakman’s method, indicated that all the broad bean and pea cultivars were susceptible to the rust isolate. Lens culinaris and Vicia spp. and Lathyrus spp., which have been reported as hosts of this rust, were inoculated by three methods of dusting, brushing and mist spray. However, no rust pustules were produced on any of these plants. Morpholgical studies on photomicrographs and scanning electron micrographs showed that urediniospores have fine echinulations and teliospores are smooth. Morpholgical studies of urediniospores of this isolate from broad bean and pea and also urediniospores of herbarium specimen of this rust on lentils revealed no significant differences for the parameters of spore length, width, number of germ pores and their positions. Also, teliospores of this isolate from the two hosts of faba bean and pea were identical in morphological features. However, statistical analysis showd that teliospores of faba rust isolate differ from those of lens isolate in parameters of spore length, apex length and pedicel length. Germinated teliospores produced four basidiospores on sterigmata. Based on the results of host range and morphological studies, and in accordance with the results of studies by Emeran et al. (2005 and 2008), the rust isolate in this investigation is suggested to be Uromyces viciae-fabae f sp. vicia faba.