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The reduction of herbicide applications is a main research priority in recent years. In order to study the effect of individual post-emergence application of sugar beet broad-leaf herbicides at four to six true-leaf stage of weeds, experiments were conducted during 2013. Treatments included untreated control and several rates of desmedipham + phenmedipham + ethofumesate, chloridazon and clopyralid on Portulaca oleracea, Solanum nigrum, Amaranthus retroflexus and Chenopodium album. A completely randomized layout with three replications was used for each herbicide. Three weeks after spraying (WAS), plants were harvested and measured their dry weight. These herbicides were more effective to control Portulaca oleracea than other weeds, thereupon minimum dose required for a satisfactory efficacy of 90% reduction of Portulaca oleracea aboveground dry matter (ED90) were 299.22, 1138.31 and 129.44 g a.i ha-1 of desmedipham + phenmedipham + ethofumesate, chloridazon and clopyralid, respectively. Solanum nigrum was more affected by clopyralid application (132.40 g a.i ha-1), and did not make significant difference in Portulaca oleracea. Chloridazon had lower effect for control of Chenopodium album due to existence of powdery covering on abaxial side of the leaves. Biomass ED50 or ED90, based on log-logistic dose–response curves, for Chenopodium album was considerably higher than other species. These results showed that tank mixtures with other herbicides may be required for satisfactory weed control and reduction in applied herbicides doses.

The photodecomposition of post emergence herbicides on leaf surface can be affected via adding vegetable oils to spray tank. Nine vegetable oils were compared to assess the photodecomposition of sethoxydim on wild oat leaf surface under simulated light conditions. The experiment was conducted as completely randomized factorial design with three replications at the College of Agriculture, Ferdowsi University of Mashhad, Iran, in 2013. Each herbicidal solution (with and without vegetable oil) was exposed to simulated light at 0, 5, 10, 20, 30, 60, 120 and 240 MAS (min after spray), for 30 min. The performance of sethoxydim in the presence of turnip, olive, soybean, corn, sunflower, canola, sesame, castor and cotton seed oils, compared to non-vegetable oil solution, increased up to 4.02-, 3.44-, 3.22-, 3.08-, 2.86-, 2.09-, 1.96-, 1.77- and 1.25- fold. All vegetable oils significantly improved the resistance of sethoxydim to light treatment. The effect of vegetable oils on the resistance to photodecomposition of sethoxydim was significant different at less than 60 MAS, while no significant differences were noted among vegetable oils when light treatment occurred at 120 and 240 MAS. Data from the light treatments have confirmed that when vegetable oils were added to sethoxydim, light adverse effect was lower, which is presumably due to disturbance of the cuticule and the rapid absorption of sethoxydim by wild oat leaves. Vegetable oils fatty acids composition effect the resistance to photodecomposition of sethoxydim, as with increasing the unsaturated fatty acid values, the resistance to photodecomposition was improved.

Carrier water quality may affect the activity of weak acid herbicides when concentrations of some cations are high. A dose-response experiment on glyphosate and imazethapyr activity, which were carried by the carrier types of distilled water and hard water, against jimsonweed were conducted to compare the water conditioning chemicals ammonium sulfate, ammonium nitrate, citric acid and potassium phosphate, with magnetized carrier as a new method. A magnetic field of 0.7 Tesla was applied to prepare the magnetized carrier. With the exception of potassium phosphate with imazethapyr, the activity of glyphosate and imazethapyr was significantly increased in the presence of the water conditioning methods when distilled water was used as the carrier. Ammonium sulfate was the most effective method. The activity of both herbicides was decreased when applied with hard water carrier. Potassium phosphate was not effective at reducing the antagonism of cations in the hard water carrier. In glyphosate, the performance of water conditioning methods in softening hard water carrier could be ranked as follows: ammonium sulfate (2.52-fold) > magnetized carrier (2.12-fold) ≥ citric acid (1.64-fold) ≥ ammonium nitrate (1.39-fold) > potassium phosphate (0.96-fold). In imazethapyr, this order was as follows: ammonium sulfate (2.99-fold) > ammonium nitrate (2.66-fold) > magnetized carrier (1.81-fold) ≥ citric acid (1.64-fold) > potassium phosphate (1.10-fold).

Introduction: The purpose of this study was to evaluate the sealing ability of 3 obturation techniques in oval-shaped canals by bacterial leakage assessment. Methods: Sixty mandibular incisors with oval canals were selected after providing buccolingual and mesiodistal radiographs. The teeth were sectioned at a 10 mm distance from the apex. After instrumentation, the teeth were divided into 3 groups and the canals in the three groups were obturated with lateral condensation (G1), warm vertical condensation (G2) and thermoplasticized injectable gutta percha (G3). The teeth were exposed to human saliva. Observing the turbidity of the BHI broth for a period of 63 days the number of days required for the complete contamination of root canals was recorded. The data were analyzed using descriptive statistical methods and Kruskal-Wallis test with SPSS statistical software. Results: Warm vertical condensation (G2) needed a significantly greater average time for leakage than the two other methods. No significant differences were found between lateral condensations and thermoplasticized injectable G.P techniques. Conclusion: warm vertical condensation provides a better seal against bacterial leakage than lateral condensation and obtura II method in obturating oval-canals.

In order to study and compare chemical and non-chemical methods of weed management in saffron (Crocus sativus) fields, two field experiments were carried out in a randomized completely block design with three replications at Research Field Station of Gonabad during 2009 to 2011. Treatments included cover crops of barely, Mushroom bed mulch, herbicides of haloxyfop R methyl ester (EC10%), iodosulfuron methyl sodium+mesosulfuron. methyl + mefenpyr. diethy (WG6%) l, hand weeding (DF75%) and control. For determining the ability of treatments for weed control, dry matter of weed, leaf dry weight of saffron, stigma and saffron flower yields were determined. Results showed that dominant weed species were mouse barely (Hordeum murinum), wild barley (Hordeum spontaneum) Hoary cress (Cardaria draba), and yarrow (Achillea millefolium). Herbicides of iodosulfuron methyl sodium + mesosulfuron methyl + mefen pyr. Diethy (WG6%) destroyed grasses and broadleaf, but it destroyed saffron plant too. Haloxyfop. R methyl ester damaged grasses but decreased stigma yield and leaf of saffron. Applied mulch was not be able to control the weeds, however, it increased saffron stigma yield. Cover crops of barley significantly decreased weed dry matter weights. Barley caused least weeds dry matter weight similar to hand weeding. In conclusion, the treatments of cover crops showed the best performances in weed control and saffron yield comparing to other studied weed management methods.

In order to study the effect of soil nitrogen content and water hardness on glyphosate efficacy on common lambsquart control, an experiment was carried out as a completely randomized design in a factorial arrangement with three replications in 2011 at the College of Agriculture, Ferdowsi University of Mashhad. Experimental treatments were included soil nitrogen content at 5 levels (0, 50, 90, 200 and 300 mg/kg soil), glyphosate doses at 7 levels (0, 75, 100, 125, 150, 175 and 200 % dose guideline glyphosate for common lambsquart), calcium carbonate concentration in water as index of water hardness at 5 levels ( 0, 100, 300, 600 and 1200 ppm). Spray was done at 8-10 common lambsquart leaf stage. 30 days after glyphosate spray, plants survival and shoot dry matter was measured. Results showed, herbicide rate, soil nitrogen content and water hardness had significantly affect (P

Sethoxydim is an acetyl-coenzyme A carboxylase (ACCase) inhibitor that changed the shape of the chlorophyll fluorescence curve (kautsky curve) in wild oat (Avena ludoviciana Durieu.) in greenhouse experiment. This experiment was conducted as completely randomized factorial design with three replications at the College of Agriculture, Ferdowsi University of Mashhad, Iran, during 2012. Results of this study revealed that sethoxydim only and plus emulsifiable turnip oil changed the shape of the chlorophyll fluorescence curve (kautsky curve) 7 days after spraying. Sethoxydim plus emulsifiable turnip oil changed the shape of the kautsky curve more than for sethoxydim only. We found that in our study the fv/fm (maximum quantum efficiency) was closely linked to the fresh and dry weight dose-response. Sethoxydim plus emulsifiable turnip oil proved more rapidly effect on fv/fm in comparison with sethoxydim only. The fresh and dry weight dose-response relationship with fv/fm showed a similar behavior. This study revealed a good relation between fresh and dry weight according with values of 28 DAS and fv/fm 7 DAS. In general, the findings of this study revealed that Fv/Fm is a good parameter for evaluating effect of sethoxydim little time after spraying. Also, this research showed that 4 folds more time for classical screening methods comparing to chlorophyll fluorescence method. Thereupon, classical screening methods may be replaced by chlorophyll fluorescence method in future.

Phenology is the study of periodic biological events. The time of weed appearance, growth and reproduction are very important for decisions on invasive weed management. Cucumis melo is an annual invasive weed of soybean fields in the north of Iran that reproduces and spreads predominately through seed production. In order to study the phenology of wild melon was conducted an experiment in CRD at Research Farm of Gorgan University of Agricultural Sciences and Natural Resources, Iran, during 2012. Seeds first germinated after 10 days of planting, as soon as optimal soil temperatures were achieved. The weed exhibited monoecious tendencies, with production of male flowers rapidly followed by production of both male and female flowers on the same vine. Cucumis melo exhibited prolific fruit production, until senescence occurred at 75 and 92 days after establishment. First fruit formation was observed between 40 and 49 days after emergence, depending on temperature. To complete growth cycle, of Cucumis melo required about 448 and 733 degree days, respectively for late of May and 8 of June. The weed produced a maximum of 100 fruits/plant, but an average plant typically produced 48 fruits/plant. The seed number and seed weight was on average about 190 seeds/fruit and 0.55 g per 100 seeds, respectively. The results indicated that wild melon could produce a lot of fruits and seeds within a growth period of about 75 and 92 days.

Smellmelon, an annual invasive weed of soybean production fields in the north of Iran, reproduces and spreads predominately through seed production. This makes seed bank survival and successful germination essential steps in the invasive process. To evaluate the potential of Smellmelon to invade water-stressed environments, laboratory studies were conducted to investigate the effect of desiccation and salinity at different temperatures on seed germination and seedling growth of Cucumis melo. Seeds were incubated at 25, 30, 35 and 40 ºC in the darkness in a solution (0, -0.2, -0.4, -0.6, -0.8, 1 and 1.2 MPa) of a salt (NaCl), and in a solution (0, -2, -4, -6, -8, -10, -12 bar) of PEG-6000 (Polyethylene glycol), in two separate experiments. The results showed that the highest percentage and rate of germination occurred at 35 ºC in salt concentrations of 0, -0.2, -0.4 MPa and PEG concentrations of 0, -2, -4 bar. Increasing the concentration of salt (NaCl) and PEG limited germination, seedling growth and water uptake but increased the sodium content in the seedlings. No significant difference was observed among 0, -0.2 and -0.4 MPa of NaCl and among 0, -2 and -4 bar of PEG concentration at 35 ºC. The negative effects of PEG were more than those of NaCl on germination percentage and germination rate. Increased stress levels lead to reduction of root and shoot length, and SVL of seedlings. Na+ content of seedling decreased with limited seedling growth of C. melo.

Introduction: Like other measures of human development, dental development is not in complete accordance to chronological age. Investigations show that dental age can be affected by gender, race, systemic conditions, and some other factors and consequently, be different in people of the same chronological age. A correct estimation of dental age and its development in children is of great importance to design the appropriate dental treatment plan. One of the factors predicted to influence dental development is the physical status of newborn, of which, the most common indices are birth weight and height. The aim of this study was to evaluate the effects of these two factors on the dental development of permanent teeth in children of both genders. Methods: The dental ages of 211 of 4-14 year old healthy children were calculated using their panoramic radiographs according to Demirjian’s method. Birth weight, height, and date were recorded from the vaccination certificate. The dental development rate was obtained by subtracting chronological age from dental age. Pearson correlation tests and regression analysis were conducted in both genders. Results: the correlation between dental development and birth weight and birth height was positive, when separated by gender; this correlation was only significant among females. Conclusion: There is a positive relationship between physical status of newborn and the development of permanent teeth. This should be taken into consideration when designing dental treatment plans for children.

Lesser celandine (Ranunculaceae) is a perennial weed with tuberous root. Tubers are the most important means of reproduction and dispersion of this weed. In recent years, it has spread into wheat fields in Western Iran, mainly in the Lorestan province. A series of experiments were conducted to determine cardinal temperatures and to study the effects of pre-chilling, temperature fluctuations, tuber size, freezing and drying on germination of the tubers, as well as the effect of planting depth on sprouting of the tubers. The results obtained showed that the highest percentage of germination occurred when tubers were stored for more than 2 weeks at 4 or 8 ºC. The optimum temperature for germination differed in large and small tubers (8 and 14oC, respectively). Germination was the highest (almost 100%) at temperature fluctuations of 5-10oC. Germination of the finger-like and small tubers was the highest (95%); however, very small, small, and broken tubers showed the lowest germination percentage. In the freezing experiment, decreasing the temperature and increasing the storage duration decreased the germination of tubers. Increasing the osmotic potential and temperature resulted in decreased tuber germination of Lesser celandine. Lesser celandine could sprout down to 20 cm depth but heat demand for tubers from superficial depth was smaller than for tubers planted at greater depth.

Introduction: Like other measures of human development, dental development is not in complete accordance to chronological age. Investigations show that dental age can be affected by gender, race, systemic conditions, and some other factors and consequently, be different in people of the same chronological age. A correct estimation of dental age and its development in children is of great importance to design the appropriate dental treatment plan. One of the factors predicted to influence dental development is the physical status of newborn, of which, the most common indices are birth weight and height. The aim of this study was to evaluate the effects of these two factors on the dental development of permanent teeth in children of both genders. Methods: The dental ages of 211 of 4-14 year old healthy children were calculated using their panoramic radiographs according to Demirjian’s method. Birth weight, height, and date were recorded from the vaccination certificate. The dental development rate was obtained by subtracting chronological age from dental age. Pearson correlation tests and regression analysis were conducted in both genders. Results: the correlation between dental development and birth weight and birth height was positive, when separated by gender; this correlation was only significant among females. Conclusion: There is a positive relationship between physical status of newborn and the development of permanent teeth. This should be taken into consideration when designing dental treatment plans for children

Introduction: The purpose of this study was to evaluate the relationship between the body mass index (BMI) and dental development. Methods: The dental ages of 196 children were calculated according to Demirjian’s method. The chronological age, weight, and height were recorded. Dental development was defined as dental age minus chronological age. Children were classified into three groups according to their BMI: underweight, normal, or overweight and obese. We used One-way analysis of variance (ANOVA), and Pearson correlation tests to analyze the data (significance level of 0.05). Results: There was a significant correlation between BMI and dental development in the girls (P=0.03, r=0.205). There was not a significant correlation between BMI and dental development in the boys (P=0.08, r=0.18). There was not a significant difference between the mean dental development and BMI group in the girls (P=0.07). There was a significant difference between mean dental development in different BMI groups in the boys (P=0.018). Conclusion: Dental development in overweight and obese boys is significantly accelerated

Abstract To study the effect of competitive potential of corn (Zea mays), in competition with common lambsquarters (Chenopodium album) an experiment was conducted in 2006, at the farm of Agricultural Faculty of Ferdowsi University. In this experiment the effect of relative emergence time of common lambsquarters on single Cross 704 corn yield was studied in different densitis of the weed. The experimental design was split plot based on randomized completed block design with three replications. The emergence time at 3 levels (emergence of the weed 14 days earlier, 7 days earlier and simultaneously with corn) was considered as main plots and density of weed at 6 levels (0, 4, 8, 12, 16 and 20 plants m-2) as sub plots. The results showed a decrease in grain and biological yield of corn, as the emergence time of corn delayed in comparison with the emergence time of weed. The maximum yield reduction of 100 and 99% was observed respectively, in the earliest emergence time of common lambsquarters compared to corn and in the highest density of weed (20 plants m-2) where the corn plants were fully shaded by the weed canopy and no ear was produced. The yield loss of corn was higher when the earlier emergence time of weed was occurred in higher weed densities. based on the results of this research it can be concluded that the decrease of competitive potential of corn with increasing the relative emergence time of common lambsquarters was led to significant yield loss of corn crop. While the increase in weed density resulted in corn yield reduction, there was no difference in yield loss in high weed densities. Keywords: Biomass, Competition, Weed interference model, Yield loss

Abstract An experiment was conducted for evaluation the allelopathic potential of extract soybean shoot on seed germination and seedling growth of four weed species tumble pigweed, smooth pigweed, common lambsqurters and black nightshade. For each species a factorial experiment was used in a completely randomized design with three replications. Plant shoots were gathered in flowering stage and individually dried and then ground. Water extracts with concentrations of 5, 10, 20 and 40 % were prepared and distilled water was used as control. Seeds of weed sat in petri dishes. Then, their germination percentage determined after 11 days. The results showed that root length, germination rate and percentage reduced in weed species when concentration rate was increased. Black nightshade had most germination percentage (88.14), root length (46.4 mm) and germination uniformity (1.5 days). Therefore, it affected with soybean shoot extract less than other weed species. Tumble pigweed had most germination rate (3 days) and its required time to achieved 10, 50 and 90% maximum germination, was about 2, 2.5 and 4 days respectively. Therefore, It was better than other species. Most inhibition effect of extracts on germination percentage belonged to smooth pigweed. Keywords: Germination percent, Germination rate, Germination uniformity, Radicle length

An experiment was carried out to evaluate the effects of planting depth and rhizome sizes on below ground growth of licorice (Glycyrrhiza glabra L.) at research glasshouse of Mashhad Unversity in 2001. Factorial experiment containing 2 factors of planting depth (10, 20 and 40‌cm) and rhizome sizes (1,2 and 3 buds or 4,7 and 10 gr) with two replications in completely randomized block design was employed. Development of different variables during growing season including root and mother rhizome dry weight were measured.The highest and the lowest root dry weight (RDW)have been seen in depth of 20 and 40 cm‌, respectively. About 100 days after planting (DAP), RDW increaseed very slowly but thenafter increased faster‌. Rhizome of any sizes in‌ 20 cm, gave the highest RDW‌. Three-bud rhizomes produced the highest RDW and 1-bud rhizome produced the lowest. Mother rhizome dry weight (MRDW) reduced untill 60 days after planting. After 75th day, MRDW has increased and all plants started to fill their mother rhizome and finally rhizome of depth 20 cm produced the highest dry weight. In 160 days after planting, mother rhizomes started to lose their weight‌. 1and 3 -bud mother rhizome produce the lowest and highest MRDW, respectively.

This study was conducted to investigate the effect of organic and bio-fertilizers on trifluralin durability.Herbicide persistence is an important consideration in crop production since residue levels of trifluralin herbicides can persist to the next growing season and may injure sensitive crops in the rotation. Residues of trifluralin persist in the soil for long periods. Extremely small amounts of resides can be devastating to some crops that are planted in the following year. Bioassay experirent is a common and cheaper experiment for herbicide residue detection in soil.In order to estimation of trifluraline halfe life in soila field experiment conducted as a factorial arrangement in completely randomized block designwith 3 replications. Experimental factor included two levels of trifluraline (EC %48) application rate480 and 960 g.Ha-1 a.i.). For determination of trifluralin residue, soil sampling was taken from 0 to 10 cm soil dept at 0, 3, 7, 15, 30, 60, 90 and 120 days after spraying. soil sampling and soil treatments were transferred to the greenhouse. The results of Bioassay experiment with sorghum plants showed decreasing trifluralin durability with the application of organic and biological fertilizer. The highest half life were observed (144 and 130 days), by using 480 g. a.i/ha related to shoot and root biomass and no fertilizer application respectively and the Least a half-life was in shoot biomass related to organic fertilizer treatment (18 and 19 days) and 480 and 960 g trifluralin active ingredient.

Tooth anomalies are rare phenomena that may be reported by patients as chief complaints or may be discovered by dentists in the oral examination. In a few cases, rare anomalies are found together in one mouth. Decision to treat such anomalies depends on whether or not they interfere with function and esthetics and also the patient's preference. In the present case, a 19-year-old male presented with two right maxillary fused central and lateral incisors and a geminated left maxillary central incisor. A talon-like projection was found at the junction site of the fused teeth. His chief complaint was sensitivity to cold at the site of the giant fused tooth. This report describes the process of diagnosis and treatment of the two anomalies according to patient preference and needs.