Morphological, biological, and phylogenetic approaches were undertaken for the identification of pathogenic species F. temperatum in the Serbian population of F. subglutinans collected in the 1999-2010 period from Zea mays (3 root, 15 stalk, and 6 seed samples), Sorghum bicolor (two seed samples), Hordeum vulgare (one seed sample) and Taraxacum officinale (one seed sample). Based on interspecies mating compatibility analyses and the maximum parsimony analysis of EF-1α sequences, only two strains, originating from S. bicolor seed (MRIZP 0418 and MRIZP 0552), were identified as F. temperatum, while the remaining 26 single-spore strains were identified as F. subglutinans Group 2. In situ detached barley leaf assay and artificially stalk and ear inoculation of two maize hybrids demonstrated that both F. temperatum and F. subglutinans strains were medium and strong pathogens under laboratory and field conditions, respectively. These are the first data on the F. temperatum as seed-borne pathogens of sorghum, as well as pathogenicity of F. temperatum strains on maize.

FUSARIUM wilt of lettuce caused by the fungus FUSARIUM oxysporum f.sp. lactucum is a destructive disease of lettuce in fields of Tehran province. A glasshouse experiment was conducted to evaluate resistance and susceptibility of 20 lettuce cultivars obtained from, Denmark, Italy, England, USA and Iran to an aggressive isolate of the pathogen. The Index of percentage of seed germination, number of healthy plants, fresh and dry weight of shoots and dry weight of roots were used for cultivar evaluation. Results indicated that Salinas and Grand Rapids were the most resisitant cultivars base on the mentioned index (P<0.05). In the field experiment nine cultivars were planted in soil with 30% infection during the previous year. A Randomized Complete Block Design with four replications was used. Plants were inoculated around the roots at the two leaf stage with spore suspension of the pathogen isolate. Results indicated that local cultivars curl Ahwazi and Esfahani with no infection were resistant. Black Shahre-Ray and King Crown with 18.42% and 26.2% of infection respectively, showed an intermediate reaction to the pathogen.

Introduction: Wilt and root rot diseases caused by FUSARIUM oxysporum and FUSARIUM solani are among the most important diseases of chickpea throughout the world and Iran. However, there is not effective chemical fungicide against these soil-borne pathogenic fungi. In recent years, rhizospheric bacteria and fungi developed as promising biofungicides against soil-borne plant pathogens. These microbes exploit several mechanisms such as antibiotics, volatile organic compounds, sidereophore and induced systemic resistance to suppress pathogenic fungi. Recently, the cost of agrochemical innovation and the period of time for their registration have increased rapidly due to stringent legislation, both of these reasons favor investment in the manufacture of biopesticides. The annual progress rate of the biopesticide bazaar is more than 16%, but that of synthetic pesticides has been decreasing by 1. 5% annually. Biopesticide companies such as Agroquest, Gustafson, Marrone Bio Innovation, Certis, BioWorks, Becker Underwood, ABiTEP GmbH, and Prophyta have released effective biopesticides to the market. Agrochemical great-companies such as Bayer CropScience have also been engrossed in the bio-pesticide market. Bayer CropScience bought Agroquest in 2012 at a price of 425 million US dollars. Overall, biological control of plant pathogens is promising technology in management of plant disease in sustainable agriculture. Materials & Methods: In this study, potential of plant growth promoting rhizobacteria (PGPRs) were investigated on biological control of this diseases in laboratory and greenhouse condition. Soil samples were collected from chickpea fields in Kermanshah and Kurdestan provinces. The effect of isolated bacteria were assessed on mycelial growth of F. oxysporum and F. solani in dual culture test. The chickpea seeds were inoculated by 109 CFU/ml of each bacterial isolates and sown in pots. The effect of bacterial isolates have been investigated on plant growth factors in greenhouse situation. The same experiment was conducted to assess the biocontrol ability of selected isolates against FUSARIUM wilt and root rot disease of chickpea. The greenhouse experiments were conducted based on completely randomized design with four replicates. Data were subjected to analysis of variance procedure in SAS ver. 9. 1 software and means compression analysis was done by Fisher protected LSD. Finally, the 16S rDNA of the four selected isolates, B2, B3, B6 and B13 were sequenced and identified based on Genebank data. Results & Discussion: Sixteen out of 100 isolated inhibited the growth of both fungi in vitro. Isolates B13 with 11 mm inhibition zone had the highest growth inhibition activity against F. oxysporum. In absence of pathogens, B2 increased aerial part dry weight from 1. 08 to 3. 69 g in greenhouse condition. B3 and B4 were the best isolates in improving root growth. They increase root dry weight to 1. 42 and 1. 36 g, respectively. B2 and B13 isolates had the greatest effect on plant health and reduced disease severity up to 90% in F. oxysporum inoculated plants. The lowest biocontrol activity against F. oxysporum was recorded for isolate B6. B2 increased aerial part fresh weight from 0. 56 to 2. 49 g, root fresh weight from 0. 24 to 1. 31 g. B6 was the best isolate for suppression of F. solani and reduced the disease index by 73%. This isolate increased aerial organs fresh weight as up to 3. 2 folds and root fresh weight up to 2. 9 folds. However, all of bacteria isolates were able to reduce FUSARIUM root rot disease, significantly. Isolates B2, B3, B6 and B13 were characterized as Bacillus sp., Achromobacter sp., Bacillus pumilus and Burkholderia sp. based on 16S rDNA sequencing, respectively. Bacillus spp. strains exploit several mechanisms such as antibiosis, volatile organic compound production and induced systemic resistance against plant pathogens. These bacteria are good candidate to be formulated in spore suspension form. Here, Achromobacter introduced as good candidate for biological control of FUSARIUM diseases of chickpea for first time. Overall, plant probiotic bacteria could be consider as promising approach in management of chickpea FUSARIUM diseases. Conclusion: Bacterial isolates have different ability in plant growth improvement and suppression of plant pathogens. Bacillus sp. was the best isolate for enhancing the shoot dry weight while Achromobacter sp. was the best to improving root dry weight. Indeed, bacteria have several mechanisms for promoting plant growth. Auxin induction by volatiles of Bacillus spp. increase root while decreasing the shoot accumulation of auxin. Overall, consortia of bacteria strains seems to be promising approach to suppression of both diseases in chickpea.

Melon is an important crop cultivated in moderate climate regions of the world. One of the most important diseases of this plant is vascular wilt caused by FUSARIUM oxysporum f.sp. melonis (Fom). The infection of farm with this pathogen can result in huge loss of yield and fruit quality of melon around the world. Genetic improvement for resistance is the best way of control of this disease. Up to now four races of 0, 1, 2 and 1, 2 have been reported among which race 1 is more versatile and dangerous than other races especially at the north half of the country. Land races such as Saveh, Rish-baba and Tile-torogh are susceptible to this race. In this research the resistance gene was transferred from Isabelle, a resistant cultivar to susceptible varieties via marker assisted backcrossing. The screening of plants in BC1F1 and BC2F1 generations was carried out using artificial inoculation. Single dominant gene of Fom-2 induces resistance toward race 0 and 1. This gene has been sequenced and there are differences between susceptible and resistant allele. In order to verify the resistant plants survived after artificial inoculation in BC2F1, the plants were genotyped by SCAR marker. The resistance of most plants was verified however there were some susceptible plants among them implying the shortcomings of artificial inoculation method and more strength of molecular method. The verified plants were crossed to recurrent parents to produce BC3F1 generation. Considering acceptable yield and fruit quality of donor cultivar and evaluation results of BC2F1 it seems that no more back crossing is needed and with the selfing of BC3F1 plants new homozygote resistant varieties will be produced.

2In this study, the antifungal effects of four species of plant essential oils, including Thymus vulgaris, Eucalyptus camaldulensis, Lavandula angustifolia and Cuminum cyminum, were studied on mycelial growth inhibition of F. oxysporum and F. culmorum isolates. The effect of essential oils was carried out in a factorial experiment in a completely randomized design with four concentrations for each essence and three replicates in 25 °C on PDA medium. The results showed that the essential oils of these plants has a significant effect on inhibition of the mentioned pathogenic isolates fungal mycelial growth. The required concentrations for the maximum mycelial growth inhibition of F. oxysporum isolate in 250 ppm for essential oils Cumin, Eucalyptus, Thyme and Lavender were 100, 96, 93 and 89 percent, and for F. culmorum isolates were 99, 96, 92 and 77, respectively. The minimum inhibitory concentrations of the cumin, Eucalyptus, thyme and lavender on F. oxysporum in 50 ppm were 48.8, 29.4, 44 and 38 respectively and for F. culmorum these concentrations were 38.8, 29.4, 44 and 18 percent respectively. The highest and lowest mycelial inhibitory growth was showed by cumin essence in 250 ppm and lavender and eucalyptus essences in 50 ppm, respectively. In all four essential oils, the growth of the fungi decreased by increasing the essential oil concentration. Regarding the antifungal and inhibitory effects of the essential oils of the plants and their low risk for humans and the environment, it seems that plant essence can be used to control plant pathogenic fungi or at least as substitution for the production of new fungicides.

In order to evaluate the effect of FUSARIUM verticillioides on seed yield, catalase (CAT) activity on polyacrylamide gel and quantum yield of maize line, a factorial experiment based on randomized complete block design with five replications during 2017 growing season at the Payame Noor University, Mamaghan branch was performed. The experimental factors were two maize lines (B73 and MO17) and two levels of F. verticillioides (control and FUSARIUM contamination). The results indicated that FUSARIUM verticillioides reduced seed yield, but enhanced CAT acivity in two maize lines. Further more, minimum fluorescence (Fo) in MO17 decreased, and increased in B73. Water splitting complex at donor side of PSII (FV/Fo) in B73 was increased, but was decreased in MO17. The level of maximum fluorescence (FM) in both line decreased. The energy necessary for closing reaction centers in PSII (Sm) and number of the QA reduction during fluorescence from Fo until FM (N) in MO17 were increased, but were decreased in B73. The results of this study revealed++ using from the chlorophyll a fluorescence can be a rapid and non-destructive method for evaluation of the maize reactions to injures caused by FUSARIUM fungi infections.