Cadmium (Cd) is one of the most toxic pollutants whose concentration in soil has been rising due to the increasing application of phosphorus fertilizers in agricultural fields. Phytoremediation, an emerging low-cost and ecologically benign technology for decontamination of soils, is defined as the process of utilizing plants to absorb, accumulate and detoxify contaminants in soil through physical, chemical and biological processes. One of the problems of this method is slow growth rate of the selected plant. Use of plant growth promoting Rhizobacteria (PGPR), especially those containing ACC deaminase, stimulates growth of plants and, thereby, improves bioremediation of Cd in contaminated soil. Therefore, to investigate the bacteria effect on the efficiency of Cd bioremediation by kale (Brassica oleraceae var. viridis), a pot-culture experiment was conducted in a completely randomized block design in the green house of agricultural college, Tarbiat Modares University, in 2009-2010. In this experiment, inoculants including: 1) control (un-inoculated), 2) Pseudomonas fluorescensstrain 169, 3) P. putida strain 108, 4) P. putida strain 11, 5)P. putida strain 159, 6) P. putida strain 4, and seven Cd concentration levels, i.e.0, 5, 10, 15, 30, 50 and 100 mg kg-1, were studied. Inoculated and un-inoculated seeds of kale were planted. Plants grew in green house for seven months.Afterwards, kale shoots and roots were harvested separately. In all treatments, Cd concentration was measured using flame Atomic Absorption spectrophotometer.The results were analyzed using SAS software and revealed that the inoculants and Cd concentration levels had significant effects on kale growth and Cd concentration in both shoots and roots (a=1%). By increasing Cd concentration, shoots and roots growth decreased, but inoculants, especially inoculant (5), decreased this effect.Maximum Cd concentrations were 136 and 58 mg kg-1 in roots and shoots, respectively, in 100 mg kg-1 Cd concentration treatment accompanied by inoculant (6). Maximum root dry weight was 1.96 gr for inoculant (4) in 15 mg kg-1 Cd concentration treatment and maximum shoot dry weight was 12.53 gr for inoculant (3) in 30 mg kg-1Cd concentration treatment. According to the noticeable amount of Cd uptake in case of the combination of the plant and the inoculants, kale accompanied by the bacteria can be considered as a reliable option for the remediation of low to moderate Cd-polluted soils (<50 mg kg-1). In high Cdpolluted soils, however, due to severe decrease in Cd translocation, kale is not a suitable plant for phytoremediation in highly Cd contaminated soils, even if inoculated with bacteria.

During rice growing season, the symptomless rice seeds from different paddy fields in Guilan province, Iran, were collected. After isolation of epiphytic and endophytic bacteria, 39 isolates including 19 epiphytes and 20 endophytes were selected based on the predominant characteristics. Five Operational Taxonomic Units (OTUs) were obtained based on PCR-RFLP of 16S r-DNA in these isolates. According to biochemical tests and partial sequencing of 16S-rDNA, in both epiphyte and endophyte bacteria of rice seeds, the most populated OTUs (V and II) were identified as Pantoea ananatis and Pseudomonas oryzihabitans, respectively. Six representative isolates from these two OTUs were selected to be evaluated for their abilities for rice seed germination and growth enhancement. Among them, P. oryzihabitans was not Beneficially effective. However, JpB1 isolate of P. ananatis was considered to be the most effective plant growth promoting isolate, since it showed stable Beneficial effects on most surveyed characteristics in both rice seed germination and growth enhancement experiments. Although, OpB3 isolate of P. ananatis produced IAA in higher amount and solubilized phosphate more than the other isolates followed by JpB1 and P. ananatis L3pB3, it was not Beneficially effective on rice seed germination.

The use of probiotics and organic acids is an ideal and suitable alternative to antibiotics in aquaculture. Currently, there is not enough knowledge about the specific and combined effects of these additives in the diet of sturgeon. Therefore, the aim of this research was to evaluate the use of lactic acid and probiotic supplements (Protexin) and their combination in the diet of Siberian sturgeon (Acipenser baerii). Therefore, 160 healthy fish with an average body weight of 54.85 ± 0.36 grams were randomly divided into 4 experimental groups in 3 replicates. Fish were fed four diets including a control diet without additives (diet 1), a control diet with 2% lactic acid (diet 2), a control diet with a combination of 2% lactic acid and 0.01% Protexin (diet 3), and a control diet with 0.01% Protexin (diet 4). Fish were fed three times a day to satiation for 9 weeks. At the end of the experiment, growth and physiological parameters were measured. The results showed that lactic acid alone and in combination with Protexin increased body weight and specific growth rate. The feed conversion ratio decreased in treatments where lactic acid was used alone or in combination with Protexin (P<0.05). Mortality rates were zero in all treatments during the experimental period. The carcass protein of Siberian sturgeon in diets supplemented with a combination of lactic acid and Protexin showed significant improvement compared to other groups (P<0.05). Addition of lactic acid and Protexin either separately or in combination led to a decrease in carcass fat content (P<0.05). The lowest intestinal pH was observed in the diet supplemented with lactic acid along with Protexin, while the highest was in the control group. Additionally, the total number of lactic acid bacteria in the intestines of fish fed with lactic acid along with Protexin showed a significant increase compared to other treatments (P<0.05). The combined addition of lactic acid with Protexin significantly increased lysozyme and complement activity in fish blood (P<0.05). In general, the separate and combined use of lactic acid (2 %) and Protexin (0.01 %) in the diet of Siberian sturgeon improved the performance of this fish.

The com armyworm (Spodoptera exigua Hub. Zimm.) is one of the most important pests of corn crop in Khuzestan province of Iran. Young corn plants are more susceptible to this insect defoliator. Microbial control of S. exigua specially by Bacillus thuringiensis Ber. is one of the most effective methods and is recommended by workers. This research was conducted to evaluate B. thuringiensis pathogenicity both in laboratory and field trials, in Khuzestan province. In prime step, different serotypes were evaluated by bioassay in the laboratory conditions. The results demonstrated that serotypes 1 and 3a3b were more virulent compare to third strain. In other bioassay, it was shown that second larval instars was more susceptible and along with larval growth and development, virulence of spores and crystal bodies lowered, significantly. Also, it was shown that in a few hours, affected larvae restrained significantly to feeding from corn leaves, compared with control. Application of surfactant agents such as triton x-100 in bacterial suspension increased virulence of the pathogen on associated host. In the field studies, virulence of B. thuringiensis was the same as the laboratory studies. Based on our results, B. thuringiensis can be accounted as an effective biological control agent for S. exigua in Khuzestan province.

Introduction: Using antibiotics to combat microbes and as a growth-enhancing tool in aquaculture is a common trend. However, scientific knowledge and public concerns about the development of antibiotic resistance have led to a global reduction or prohibition of these compounds. Probiotics and organic acids are potential alternative compounds to antibiotics in aquaculture. Numerous studies have been conducted on using organic acids in poultry and livestock diets. However, there is limited information regarding the employment of these compounds in fish nutrition. Nowadays, various probiotics are used as dietary supplements in the aquaculture industry. However, combining organic acids and probiotics is a new idea that has not yet been studied. Materials and Methods: In this experiment, the effects of butyric acid and probiotic supplements (Protexin) and their combination on the growth performance, body composition, intestinal microbiota, and immune responses (lysozyme and complement) in juvenile Siberian sturgeon (Acipenser baerii) were investigated. Therefore, 120 healthy fish with an average body weight of 54.85 ± 0.36 g were randomly divided into four experimental groups in three replications. The fish were fed with four diets as follows: control diet (C1, without supplementation), diet containing 2% butyric acid (T2), diet containing a combination of 2% butyric acid and 0.01% protoxin (T3) and diet containing 0.01% protoxin (T4). The fish were fed three times a day until satiation for 9 weeks. Results and Discussion: The results showed that T2 and T4 improved the growth indices of Siberian sturgeon (p < 0.05). In control and T2, the body fat contents decreased. The protein level significantly upraised in T2 (P<0.05). Adding organic acid to the fish diet dropped pH and elevated intestinal lactic acid bacteria (P<0.05). Lysozyme and complement increased in T2 and T3 (P<0.05). Conclusion: In general, the results of this study showed that butyric acid alone had a positive effect on growth, intestinal microbiota, increasing lactic acid bacteria, and the immunity of Siberian sturgeon. Although its combination with protoxin was ineffective on the increasing growth, however, it improved the intestine-Beneficial bacteria and fish immunity.

In this research, the interaction between two biocontrol strains of Pseudomonas fluorescens (PF153mcherry and CHA0gfp2) 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.