Objective Root structure modification is associated with the efficient water uptake and the nutrient utilization. It also provides structural support for the anchoring in soil. Genetic engineering for the improvement of plant root structure may help to maintain higher yields under drought conditions. The aim of this study was to modify the root structure of rice in order to improve drought tolerance and the efficiency of nutrient uptake. For this purpose, simultaneous transformation of Deeper Rooting1 or OsDRO1 gene, which is involved in the regulation of growth angle of the root in order to adapt to drought conditions, and phosphorus-Starvation Tolerance1 or OsPSTOL1 gene, which is effective in increasing phosphorus uptake and improving root structure, were considered for rice root structure modification. Materials and methods The OsDRO1 and OsPSTOL1 genes derived from the wild rice cultivars were cloned together in a single construct under the control of the root specific and the ubiquitin promoters, respectively. The resulting construct, pUhrDroPstol is transformed into the Agrobacterium tumefactions strain EHA105 and used for the gene transformation into Hashemi cultivar. Putative transgenic plants, survived on 50 mg/L Hygromycin during tissue culture steps, are transplanted into the Yoshida solution and then into the pots until they set seeds. Construct specific and gene specific PCR analysis are used to confirm the transgenic plants. Results In this study, 12 putative transgenic rice events were obtained, of which 10 showed the presence of both OsDRO1 and OsPSTOL1 genes in the PCR analysis. Transgenic plants show stronger root structure compared to the non-transgenic ones. Molecular analysis in the T1 and T2 generations determined the homozygous events. Conclusions In this study, two candidate genes affecting root structure, nutrient uptake and drought tolerance were transferred to the Hashemi rice using genetic engineering. So far, simultaneous transfer of these two candidate genes have not been reported. Transgenic plants present better root system compared to the control plants. The mentioned construct can be used for the transformation of other crops to improve their root structure, nutrient uptake and their drought tolerance. It is hoped that the production of the transgenic rice with modified root structure and efficient phosphorus uptake increases its drought tolerance and reduce water consumption in rice cultivation.

Information of P fractions in sewage sludge treated soils is necessary for better management of land application of organic amendments. The purpose of this study was to evaluate the effect of sewage sludge on the forms and distribution of P in a calcareous soil using a sequential fractionation procedure. A greenhouse experiment with six levels of sewage sludge (0, 22.5, 45, 90, 180 and 360 ton ha-1) was conducted as a completely randomized design with four replications with wheat plant for 90 days. In comparison with the control, sewage sludge application significantly increased all P forms. Among various P fractions, Labile P showed the largest increase. In the control soil, the various P fractions could be ranked in the following order: HCl-P>OAc-P>CBD-P>NaCl-NaOH-P>Labile-P. In contrast, the order in biosolid-treated soils follows: HCl-P>OAc-P>Labile-P>CBD-P> NaCl-NaOH-P. In general, the results demonstrated that the dominance of inorganic P forms in sewage sludge. Inorganic P forms represented 80% of total P in biosolid-treated soils and 57% in the control. In control soil and biosolid-treated soils, Ca-associated Pi was the dominant fraction. Application of sewage sludge significantly increased the concentration of P in shoots of wheat compared with the non-manured control.

Introduction and objective: The appearance of resistance to anti-tuberculosis drugs has generated research to find new and more effective drugs. Lowenstein-Jensen medium (LJ) is frequently used for culturing strains of Mycobacterium tuberculosis. A group of antimicrobial substances used in treating tuberculosis is sensitive to heat and cannot be used on LJ medium. Research now aims to setup a modified method for evaluation of heat Labile drugs in LS medium.Materials and methods: In this study, we investigated culturing M. tuberculosis for 48h on Middle brook 7H9 broth medium with antituberculosis drugs and re culturing on LJ medium (without antibiotic) and incubating for 40 days.Results: Our results after 48h of contact of the strains with antibiotic were comparable with the standard method of culture on Middle brook 7H10 agar medium containing antibiotic. Therefore, 48h is a suitable time for primary contact between mycobacterium and heat Labile antibiotics.Conclusion: This modified method can be applied to LJ medium instead of expensive Middle brook 7H10 agar medium for evaluation of heat Labile anti tuberculosis drugs.

Tillage can significantly influence the productivity and sustainability of modern farming systems. In addition, the chemical nature of soil P is affected by tillage practice. The aim of this work was to determine changes of inorganic P fractions in a soil (Labile, moderately Labile, nonLabile, residual) under different tillage managements using Bowman and Cole (1978) procedure. Soil samples were taken from four different tillage treatments {conventional tillage (CT), Raised Bed Tillage (RB), Minimum Tillage (MT) and No-Tillage (NT)} from 0-8 and 8-16 cm depths with a factorial randomized complete block design with 5 replicates. The results showed that the tillage systems had significant effect on total P and all inorganic phosphorous except on nonLabile inorganic phosphorus. The change in soil tillage from conventional to conservation tillage significantly increased the amount of inorganic phosphorus forms (Labile P, moderately Labile P, residual P). The most significant variation belonged to in Labile inorganice phosphorus, in which the amount of Labile inorganic phosphorus in conventional tillage (9. 51 mgkg-1 ) increased to 21. 37 mgkg-1 in minimum tillage (MT), indicating an increase of approximately 2 times compared to conventional tillage. No-tillage treatment showed the highest amount of moderately Labile P (678 mgkg-1 ) and the lowest amount (580 mgkg-1 ) was in conventional tillage. The highest and lowest amounts of total inorganic P (522. 95 and 441. 98 mgkg-1 ) were observed in No-tillage and conventional tillage, respectively. The results of this study indicated that the change in soil tillage from conventional to conservation tillage has considerable effect on soil P reserve.

The distribution of phosphorus (P) forms is very important to evaluate the soil P in calcareous soils. Organic fertilizers increase the soil P dynamics by adding organic matter. This experiment was conducted by using 50 mg P kg-1 soil from sheep manure (SM), municipal solid waste compost (MSWC) and triple superphosphate (TSP) treatments with control (without fertilizer) in a calcareous soil in greenhouse conditions. At the end of the plant's physiological growth, dry weight of shoots, phosphorus concentrations of wheat, organic and inorganic forms of soil P were measured. The results showed that by using of 50 mg P kg-1 soil from SM, the highest P uptake by wheat was obtained from TSP treatment. All organic P forms significantly increased (P<0. 05) in comparison with the control, but Highly Resistant Organic phosphorus (HROP) showed invers trend. Moderately Resistant Organic phosphorus (MROP) had the highest of organic P fraction and the Labile Organic phosphorus (LOP) was the least. The highest fraction of mineral phosphorus was the apatite form. By applying of 50 mg P kg-1 soil from SM and TSP, Ca2P form increased by 4. 2 and 3. 9 times compared to control respectively. The AlP form increased by applying SM. MSWC and TSP treatments at 31. 0, 44. 0 and 46% compared to control, respectively. According to the research data, with the application of 50 mg P kg-1 soil from the source SM, increased organic phosphorus forms and by 50 mg P kg-1 soil from the source TSP, increased phosphorus absorption and its mineral forms in wheat cultivation...

Background and Objectives: phosphorus (P) deficiency is frequently reported in many regions of the world, certainly in calcareous soils of arid and semi-arid regions. In calcareous soils, the soluble P is rapidly converted to insoluble precipitates of Ca-phosphates due to high content of CaCO3. Soil organic phosphorus (SOP), which can comprise up to 80% of the soil P, plays a significant role in P nutrition of crops specially in high P fixing calcareous soils. Soil organic P is a heterogeneous mixture of organic substances and the different fractions of SOP might have different effects on soil fertility and quality. Organic amendments such as sewage sludge and animal manures can be recycled to agricultural lands as a source of organic matter and phosphorus. Organic amendments may influence P dynamics in soils. This study was conducted to investigate the short-term (100 days) effects of some organic amendments on the soil organic P (SOP) fractions and their availability to wheat in a calcareous soil.Materials and Methods: A calcareous soil, which suffer from P deficiency, was collected in summer 2013 from Kerman province, air-dried, crushed and transferred to pots including two levels of sewage sludge (SS), cow manure (CM), poultry manure (PM) and no organic amendment (CO) in four replicates. Four wheat seeds were sown in each pot and kept for 100 days in a controlled greenhouse. At harvest, shoot dry weight and shoot P concentration were measured. Soil organic P fractions including Labile organic P (LOP), moderately Labile organic P (MLOP), moderately non-Labile organic P (MNLOP) and non-Labile organic P (NLOP) was also measured.Results: Soil application of organic amendments significantly increased shoot dry weight and shoot P uptake of plants. The highest values were found in soil amended with 4% level of sewage sludge. Organic amendments markedly (P<0.05) increased all organic P fractions compared with the control. Moderately Labile organic P was affected by organic amendments more than the other fractions. Regardless of applied levels, the magnitude effect of organic amendments on different OP fractions was ranked in the following order: SS>CM>PM. A significant correlation was observed between Labile organic P with soil available P (r=0.92**), P uptake by wheat (r=0.92**) as well as between MLOP and shoot dry weight (r=0.96**), showing that Labile and moderately Labile organic P fractions have more contributors to available P than the others.Conclusion: These results suggest that adding of organic amendments can increase P availability and plant growth due to increase in soil OP fractions especially Labile and moderately Labile organic P fractions.

BACKGROUND AND OBJECTIVES: Disinterred manures from dumpsites in the cities are believed to be readily available source for soil nutrient for backyard farming. Health hazards posed on human due to Labile metals contaminants are not considered or evaluated before consumption. Three major municipal dumpsites from Okitipupa (Waste Management (OKA), Igodan(OKB), and Okitipupa Oil Mill Road (OKC)) were analyzed for the concentrations, forms of Labile metals in the soil and also concentration in green vegetables from the sites. The objectives of the research were to investigate the Labile metal concentration, forms of the Labile metals in the soil and their accumulation in plants from these major urban dumpsites. METHODS: Dried and digestedSoil and vegetable samples from the sites were analyzed for total concentration of Labile metals and their forms through speciation in the soil were equally quantified. Concentrations from sample solutions were determined by Atomic Absorption Spectrophotometer. FINDINGS: Labile metals concentrations from the soilof Waste Management Dumpsite (OKA), IgodanDumpsite (OKB) and Okitipupa Oil Mill Road Dumpsite (OKC) indicated that Cadmium (Cd) values range from87. 453mg/kg-106. 500mg/kg). Copper (Cu) in the three samples ranged between 3. 100-5. 510mg/kg, which are significantly low and beyond the toxicity level as well as cobalt (Co). Chromium (Cr) was higher in OKA (22. 980mg/kg) and OKC (10. 560mg/kg) and least in OKB (2. 900mg/kg). Iron was the most abundant ranging from 3690. 000-6780. 000mg/kg, followed by zinc ranging from385. 000-2880. 000mg/ kg. Speciation of the Labile metal indicate that the metal exist mostly in the inert fraction and easily absorbed by plant. CONCLUSION: The concentrations of the most Labile metals in soil samples were high and majorly exist in inert fraction after speciation. Also, the concentrations in the plants were almost half of the concentration in the soil which indicated that they are not desirable for human consumption due to their toxicity level.