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Problem statement: High level of biosafety and non adverse effects on the environment of biocontrol strategies of pest management, are priorities of tomorrow's world agriculture. Actinomycetes are active biocontrol agents due to their antagonistic properties against wide range of plant pathogens particularly fungi. Fungal pathogens are liable for a big part of damages in agriculture economy. Approach: In the present research antifungal bioactivity of 50 isolates of Actinomycetes collected from soils of Kerman province of Iran was investigated against Sclerotinia sclerotiorum (Lib.), the causal agent of stem rot in sunflower, through agar disc method and dual culture bioassays. The Streptomyces isolate No. 363 was propagated in submerged cultures and active crude was prepared upon which several biological characterizations performed. Greenhouse studies were achieved to confirm laboratory results. Results: Among the tested Streptomyces isolates, 10 isolates revealed antagonistic properties in dual culture procedure from which isolate No. 363 showed highest bioactivity. The active metabolite of Streptomyces isolate No. 363 was polar and well soluble in H 2 O. Using agar-disc method, progressive growth of the pathogen was highly reduced by the antagonist through exhibiting ability to constitute fungus-free zones of inhibitions. The results indicated that isolate No. 363 was a proper candidate for field biocontrol studies. Conclusion: Results may open a horizon for production of resistant transgenic plants having antifungal properties originated from biologically active Streptomyces spp. recognition and production of effective metabolite(s) of Streptomyces spp. which was responsible for antifungal activities will be our commercial goal due to rich reserves of soil borne Actinomycetes in Iran.

Background The main objectives of this study were to find the possible structural association between the activity of enzymatic antioxidants and the grain yield of triticale plants as well as identifying the genotypic variability which might be effective on this association. Accordingly, expression levels of superoxide dismutase (SOD) isozymes (Mn-SOD, Cu/Zn-SOD, and Fe-SOD) were appraised to distinguish any possible relationship between SOD expression and drought resistance of triticale. A novel analytical method for distinguishing elite genotypes based on measured features was proposed. Additionally, a new programing based on SAS-language (IML) was introduced to estimate the genetic parameters rooted from combined ANOVA model (linear mixed model), which is capable of being used in any field study other than the current one. Methods Thirty genotypes of triticale were studied under normal and drought stress conditions during 6 years (three different locations). Accordingly, based on the results of genetic variability, heatmap analysis, biplot graph, and clustering technique, two genotypes with the highest genetic distance were selected to appraise the differential expression profiling of three SOD isozyme in shoot and root organs. Results Field experiments and bioinformatics results showed that superoxide dismutase (SOD) was the most influential antioxidant in resistance of triticale to drought stress; therefore, it could be used as an indirect selection index in early stages to distinguish resistant genotypes to drought stress. Additionally, Mn-SOD and Fe-SOD showed roughly similar expression levels for both genotypes under drought stress. However, Cu/Zn-SOD expression level was higher in root and shoot of the tolerant genotype than the susceptible genotype. Conclusion Heatmap analysis that is applied for the first time to screen suitable genotypes, showed to be highly capable of distinguishing elite genotypes and pointing out the proper features for selection criteria. Bioinformatics results indicated that SOD is more important than other enzymatic antioxidant for being considered as selection criteria or candidate gene for transgenic purposes. Based on expressional results, Mn-SOD announced as a general isozyme that is probably highly expressed in most of the species, while, Cu/Zn-SOD was introduced as a genotype specific isozyme that is likely more expressed in tolerant genotypes

Background: Antibiotics are extensively used as therapeutic, prophylactic and growth promoting agents in the poultry industry. However, their widespread use resulted in the presence of residuals in poultry meat and offals potentially leading to public health hazards. The present research was done to assess the distribution and concentration of residual antibiotics in chicken meat and liver samples. Methods: Ninety chicken meat and liver samples were collected and transferred to laboratory. Presence and concentration of residual tetracyclines, sulfonamides and trimethoprim were assessed using the Liquid Chromatography -Tandem Mass Spectrometry technique. Results: There were no detectable concentrations of tetracyclines in all studied samples. Twenty-eight out of 90 (31.11%) raw meat and 31 out of 90 (34.44%) liver samples were positive for residual sulfonamides. Prevalence of positive meat and liver samples for residual sulfachloropyrazine, sulfadimethoxine and trimethoprim antibiotics were 16.66%, 5.55% and 8.88% and also16.66%, 5.55% and 11.11%, respectively. Sulfathiazole residue was only detected in 1.11% of chicken liver samples. Chicken liver samples had the higher concentrations of all detected residual sulfonamides. Sulfachloropyrazine had the highest concentration in raw chicken meat (20.8±1.88 µg/kg) and liver (24.4±1.54 µg/kg) samples, while sulfadimethoxine had the lowest (6.05±0.25 µg/kg and 9.26±0.36 µg/kg, respectively). Conclusion: All detected concentrations of residual sulfonamides were lower than Maximum Residue Limits (MRLs). Presence of residual antibiotics represents a serious public health treat regarding the occurrence of antibiotic resistant bacterial strains. LC MS/MS has been introduced as a sensitive and specific technique for monitoring and surveillance of residual antibiotics in chicken samples.

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