During 1997 to 1999, five races of T. laevis were reported from different parts of Iran. In the present investigation some new Pathotypes of the pathogen which are new for Iran or for the world are reporting. Wheat spikes infected with T. laevis were collected from different areas. Teliospores obtained from a single spike were considered as an isolate. Teliospores of each isolate were used to inoculate seeds of differential cultivars. Infected seeds were grown in a bunt infection free field in Karaj, and at the harvesting time, percentage of infected spikes for each cultivar and isolate were assessed. The virulence factors in each isolate and the related races were determined. Ten isolates from Khosroshahr, Shirvan, Maragheh, Ardabil and Uromieh had nine new combinations of virulence factors, which had not been included in the previously published race determination tables, therefore these combinations are described as L-20 - L-28 Pathotypes as follows: L-21, isolate No. 1 from Khosroshahr, virulent on genes Bt2, 3, 7, 8, 9; L-22, isolate No. 2 from Khosroshahr, virulent on genes Bt7, 8, 13; L-23, isolate No. 1 from Shirvan, virulent on genes Bt3, 4, 7; L-24, isolate No. 2 from Shirvan, virulent on genes Bt2, 3, 7, 8, 13; L-25, isolate No. 1 from Maragheh, virulent on genes Bt7, 9; L-20, isolate No. 2 from Maragheh, virulent on genes Bt7_ 8; L-26, isolate No. 1 from Ardabil, virulent on genes Bt2, 7, 9, 15; L-27, isolate No. 2 from Ardabil, virulent on genes Bt2, 3, 7, 8; L-28, isolates No. 1 and 2 from Uromieh, virulent on genes Bt3, 7, 8. Virulence frequencies of these new Pathotypes for resistance genes Bt2, Bt3, Bt4, Bt7, Bt8, Bt9, Bt13 and Btl5 were 40%, 60%, 10%, 100%, 70%, 30%, 20% and 10%, respectively. As genes Btl and Bt6 are susceptible to races L-4 and L-17, previously reported in Iran, therefore genes Bt5, Bt10, Bt11, Bt12, Bt14 and Bt p are still resistant to the new Pathotypes and races present in Iran.

The stripe (Yellow) rust in wheat is one of the most important plant diseases in Iran. Since 1993 several epidemics have occurred in Iran causing the breakdown of widely utilized sources of resistance in wheat cultivars. Twenty-seven Pathotypes were identified during 2003 and 2004 in greenhouse tests. Pathotypes 6E6A+, 6E22A+, 6E130A+, 6E134A+, 6E142A+, 6E158A+, 134E130A+ and 134E142A+ were more common during the course of this study. Virulence on plant/s with gene/s Yr2, Yr6, Yr7, Yr8, Yr9, Yr24, Yr25, YrSD, YrSP, Yr3N, Yr2+, Yr6+, Yr9+, Yr7+, Yr32+ and YrA was detected under greenhouse conditions. The majority of isolates with a high frequency (more than 88%) showed virulence on plant/s with Yr2, Yr6, Yr7, Yr9, YrA and Yr24 genes. No virulence was detected on plant/s with Yr1, Yr3V, Yr4, Yr5, Yr10 and YrSU genes. In a greenhouse test, frequency of virulence to wheat genotypes with the Yr32+, YrSP and YrSD gene was less than 7%; frequency of virulence to all other wheat genotypes was between 19 and 100%. During three years of field study, virulence on wheat genotypes Heines Kolben (with genes Yr2 and Yr6), Kalyansona (Yr2), Lee (Yr7), Avocet R (YrA), Federation*4/Kavkaz (Yr9) and TP1295 (Yr25) was common. No virulence was observed on plants with Yr1, Yr3V, Yr3N, Yr4, Yr5, Yr8, Yr10, Yr18, Yr24, Yr32+, YrSP, YrSD and YrSU genes in the trap nurseries. The coefficient of infection (C. I.) of the adult plant resistance gene, Yr18, was between 16-64 with moderate susceptibility and is going to be used in the breeding program in combination with other resistant sources.

Background and Objectives: Diarrheagenic Escherichia coli (DEC) is an emerging agent among pathogens that causesdiarrhea. Studies showed that diarrheagenic E. coli such as enterohaemorrhagic E. coli (EHEC), enteroaggregative E. coli(EAEC), enteropathogenic E. coli (EPEC), enteroinvasive E. coli (EIEC), enterotoxigenic E. coli (ETEC), diffusely adheringE. coli (DAEC) and shiga toxin producing E. coli (STEC) strains are among the most frequent causative agents in acutediarrhea. The aim of this study was to determine the frequency of DEC Pathotypes in Khuzestan province.Materials and Methods: Stool samples were collected from patients with diarrhea in Khuzestan province of Iran. E. colistrains were isolated using conventional culture and standard biochemical tests. The polymerase chain reaction (PCR) techniquewas used to detect presence of virulence genes, i.e; eae, stx1 and stx2 for EHEC, bfp and eae for EPEC, LT and ST forETEC, AA for EAEC, invE for EIEC, stx1 and stx2 for STEC.Results: Altogether, 200 stool samples were obtained from patients, of which 158 (79%) were positive for E. coli. DEC wasidentified in 127 (63%) of stool samples, which frequency of each Pathotypes were as follows: atypical EPEC 49 (39%), typical EPEC 1 (0.7%), STEC 50 (39.3%), ETEC 21 (16.3%), EAEC 5 (4.0%) and EIEC 1 (0.7%). Most frequent etiologicalagents of diarrhea in Khuzestan province of Iran were STEC and EPEC.Conclusion: Our findings showed DEC had been agent of diarrhea in Khuzestan. This finding provides evidence that effortshould be made to estimate the burden of infection by the etiological agent for better medical approach and should raisenotification about antibiotic resistance among bacterial infection.

Diarrheal strains of Escherichia coli (DEC) are common pathogens that cause acute intestinal diseases in humans through the consumption of contaminated food. The present study was conducted on 240 samples including strudel, pizza, sandwiches, and salad. E. coli was isolated by conventional culture tests and confirmed by PCR (using uidA gene). Out of 240 samples, 123 isolates (51. 25%) were found positive as E. coli. Amongst 103 isolates (42. 9%) contained no pathogenic genes. 11 isolates (4. 6%) were identified as EPEC, 5 isolates (2%) as EHEC, 2 isolates (0. 8%) as EAEC. ETEC and EIEC were not detected in any of the samples. Due to the contamination of ready-to-eat food samples with intestinal pathogenic Pathotypes, continuous monitoring of the field of ready-to-eat food is suggested.

Background and Objectives: Intestinal Pathotypes of Escherichia coli belong to the companion animals may poses po-tential risk to public health following zoonotic transmission. Therefore, this study was proposed to determine the virulence genes associated to diarrheagenic E. coli strains isolated from healthy pet dogs and their owners in the southeast of Iran, Kerman province. Materials and Methods: Totally 168 E. coli isolates were collected from 49 healthy household dogs and their owners. Sev-enty isolates were obtained from non-pet owners as control group. Presence or absence of the virulence genes including eae, stx1, stx2, st1, lt1, ipaH, cnf1 and cnf2 were screened by conventional polymerase chain reaction (PCR) and dissemination pattern of the genes were studied among the various hosts. Results: PCR examinations showed that the most frequent virulence gene was ipaH (6. 1%) in dogs followed by eae in dog owners (6. 1%) and in controls (8. 6%). The most frequent Pathotypes in dogs, their owners and controls were EIEC (6. 1%), EHEC (4. 08%) and EPEC (8. 5%), respectively. In one of studied houses, both of dog and its owner harbored E. coli strains with same virulence profile (stx1/eae) and pathotype (EHEC). Conclusion: These results collectively indicate that healthy household dogs probably are the mild reservoir of potential virulent E. coli strains with possible active transmission to their contact owner. However, even non-pet owners seemed to be a notable source of intestinal Pathotypes, especially EPEC, for their environment. Transmission of E. coli Pathotypes may occurs by direct contact with the reservoirs or ingestion of contaminated food. These Pathotypes are potentially virulent and creates public health hazards. Further studies are needed for better understanding of dissemination mechanisms of E. coli Pathotypes among humans and their pets.

Background: Diarrheagenic Escherichia coli (DEC) are major causes of diarrhea in the world particularly among infants and young children.Objectives: The aim of this study was to determine the prevalence of DEC strains in stool samples from children under 5 years old.Patients and Methods: Stool specimens were collected from 200 children under 5 years visiting hospital due to gastroenteritis. E. coli Pathotypes were detected by using conventional culture techniques and polymerase chain reaction (PCR).Results: Sixty-eight (34%) out of 200 specimens were positive for DEC. Different Pathotypes would show the following profiles: 43 (21.5%) for enteropathogenic E. coli (EPEC); 18 (9%) for enterotoxigenic E. coli (ETEC) including 10 (55.5%) st positive, 6 (33.3%) lt positive and 2 (11.1%) st and lt both positive; 6 (3%) for enteroaggregative E. coli (EAEC) and 1 (0.5%) for enteroinvasive E. coli (EIEC). Enterohemorrhagic E. coli (EHEC) was not isolated from any of the E. coli strains tested.Conclusions: This study shows that DEC is a common cause of childhood diarrhea in Babol. EPEC and ETEC were the most frequent Pathotypes in the population under study.

Identification of resistance sources against Ascochyta blight Pathotypes is necessary to use in chickpea breeding programs. Plant breeders accept screening of crop germplasm as useful gene pool against biotic and abiotic stress. Ascochyta rabiei is one of the most important constraints to chickpea production in the most area of world especially in Iran. In this study, reactions of 420 chickpea accessions and 97 lines and cultivars from Ferdowsi University of Mashhad were evaluated to find resistant sources against six Pathotypes of Ascochyta rabiei by artificial infection using mix spore suspension in field and greenhouse conditions, during two years (2003 and 2004). In first step, the seeds were sown in field and inoculated using mix spore suspension of six Pathotypes in five to seven leaf stages. The humidity and the temperature were regulated using mist irrigation system during a week after inoculation to distribute disease in field. The disease severity was scored on a scale of 1 to 9, when susceptible lines death. In this step 63 accessions with the scales 2 to 4 showed high resistant levels against the Pathotypes. These accessions were inoculated again by the spore suspension in greenhose in different developmental stages i.e., planting, flowering and podding. The diseases symptoms were scaled two weeks after each step of inoculation. Nine accession showed high resistant level in greenhouse. The average of disease severity was higher in greenhouse compared to that of the field. Differentiation of resistant and susceptible accessions was correctly done in podding stage. According to filed and greenhouse evaluations two desi accessions (MCC 54 and MCC 523) and six Kabuli accessions (MCC 496, MCC 133, MCC 299, MCC528, MCC 3.11 and MCC 142 were resistant against six Pathotypes of ascochyta blight. These accessions can be used as resistant sources in chickpea breeding programs.