Year:2007 | Volume:12 | Issue:4|Papers Count:25

Rice is a grain that helps to food supply for two-thirds of the world’s population. Gilan province is one of the important regions in the field of rice production in Iran. At this study, the alternative rice marketing strategies were evaluated using three analysis methods. These methods included MOTAD1, simulation and GSD2. Historical rice prices from 1370-83 was used and tested for trend and seasonality in order for the methods to be formed properly. In this relation, the needed information was obtained from market factors, as well as relevant organization by questionnair, interview and clustering sample. The best strategies involves selling 30 percent of rice in Mehr and 70 percent in Farvardin, because this strategies involve the highest level of risk also brought in the highest average net returns. After the MOTAD analysis, simulation analysis was conducted to improve the results from the MOTAD analysis. In simulation analysis, is was selected top 20 marketing strategeis from 1146 strategies and the best strategies involves selling 100 percent product in Farvardin and direct sell from producer to consumer. The results obtained from the stochastic analysis showed very similar results to the simulation analysis results.

In this research, antifungal effects of some antagonistics bacteria were investigated against Rhizoctonia solani Kuhn, the causal agent of rice sheath blight, collected from infected rice field in Rasht, Lahijan, Foman, Talesh and Astara of Guilan province. Of 288 bacterial isolates, cultured from hizosphere of infected rice Plants, eight G-Ve strains were considered as antagonists demonstrated by dual culture method. According to results of biochemical and morphological test, all eight isolates encoded B4, B6, B17, B18, B22, B24, B41 and B42 were identified as Pseudomonas fluorescens biovar 3. In determining the effects of volatile metabolites produced by antagonistic bacteria, all strains, inhibited mycelial growth of R. solani under in vitro condition. Culture filtrates and antibiotics produced by these strains could inhibit the normal growth of the pathogen. All P. fluorescens strains produced siderophore on King’s B containing 5, 50 and 100 μmol FeCl3 which in turn inhibited growth of the Geotrichum candidum on the other hand, all P. fluorescens strains reduced the rate of fungal germination and caused lysis of R.solani sclerotia. The bacteria colonization experiment showed that the population density of strains B42, B41 and B22 were increased on rice root system to 3.67, 2.98 and 2.94 CFU logarithm, respectively.

The Russian Wheat Aphid, globally regarded as an important cereal pest, has extended its distribution throughout the country and in wheat fields of East Azarbaijan in particular. Biological responses of the aphid to work out any possible susceptibility or resistance in five extensively planted wheat cultivars in the province named as Alamoot, Alvand, Zarrin, Sabalan and Sardari, have been already studied at tillering and stem elongation stages in the greenhouse as well as at 3 growth stages under field conditions by the authors. In the present work, attention has been paid to the biological responses of the aphid on these cultivars at ear emergence stage under greenhouse conditions of 20.52 ± 1.4 temp., 55-70 % R.H. and 14:10 (L: D) regime. The probable antibiosis in determination of resistance or susceptibility of cultivars to the aphid was studied by measuring the nymphal survival rate, mean development time and adult fecundity. Determining the total progeny number / female produced within the first 10 and 15 days of reproductive stages, the relevant intrinsic rate of natural increase (rm value) was estimated. The ANOVA of the data indicated that regarding duration of nymphal development time, adult fecundity and also rm values, there were significant differences (P < 0.05) between the cultivars. Based on this, the highest (8.90 ± 1.0) and lowest (7.90± 0.96) mean nymphal development time was calculated on Alvand and Sabalan respectively. The greatest (34.94 ± 5.91 and 48.56 ± 7.66), and the least (24.83 ± 9.36 and 36.67 ± 13.67), numbers of progeny produced / female within the first 10 and 15 days of larviposition period, was observed on Sardari and Alvand respectively. Moreover, the highest rm value (0.2677 ± 0.02 and 0.2636 ± 0.02) obtained for individuals reared on Sardari, with the lowest (0.2174 ± 0.03 and 0.2234 ± 0.03) being on Alvand. The present study indicated that at ear emergence stage, Sardari appeared to be susceptible to the aphid whilst Alvand and Zarrin were more resistant, and Sabalan and Alamoot showed partial resistance.

Canola (Brassica napus.L) cultivation has increased because of high percent oil and quality at different climate of Iran recently. Determination of water requirement is necessary for crop cultivation in arid region. This research was carried as randomized block desingn with 3 replications with four treatments including of I1=50 I2=75, I3=100 and I4=125 evaporation rate (mm) from pan (Class A) at Arak station.Grain yield, 1000-grain wieght, oil yield, dry matter weight, height plant, pod per plant, grain per pod and water use efficiency was mesaeured. Effect of irrigation was significant on grain yield and yield components, but interaction effect of irrigation and year was significant on pod per plant only. A difference in grain yield was affected from pod per plant and grain per pod. Statistical analysis showed that I1and I4were maximum and minimum amounts respectively, at all of variable. I1 treatment has significant effect on grain yield, height plant and grain per pod. I1and I2 had not significant differences on oil yield, pod per plant and WUE. Conclusionly I2 treatment recommend for similary Arak claimatic condition.

Nowadays, one of the most important problems in the educational programs is that rural people are not interest to take part in extention and educational activities because educational activities have not related to their needs that results in reducing interest and motivation among rural people and wasting extension staff’s capital, time and energy of extension personnel. According to above, in this study it has been considered in terms of sericulturist’s educational needs. We know that sericulturists provides a part of currency; In addition to production of silk. The descrptive- correlation research methodology was used in this study. Dependent variables include obstacles and educational needs. Independent varianles are sericulturists individual, personality, social and economical charactristics. The population for this study consisted of 382 serculturists of ghasab mahaleh, fetedeh and bazneshin sofla villages. Sampling methods is cluster and questionnaires were completed by interviwers. Results indicated there are positive significant relationships between communication rate, participation rate, acquiring scientifical information from extension departments, methods of acquiring information, main and secondary career, the kind of mullberry farm ownership, visit of other sericulturists mullberry farms, acquiring scientific information fram radio and TV with educational needs relating to sericultures. Also, there are negative significant relationships among age, literacy, income rate, take part in educational cources , reading magazines with educational needs relating to sericulture; but there is not significant relationships between gained income from sericulture, number egg boxes, record of sericulture with educational needs. Forthermore, based on sericulturist’s opinions, the best method for education was practical method.

In this study the effects of serpentine rocks on some physico-chemical properties of soil and waters have been considered. The serpentinite is the products of pyroxinite and dunite alteration. The dominant mineral of serpentinite is serpentine and a less amount of chlorite and magnentite. The mentioned rooks are very sensitive to weatheying and have considerable effects on soil and water quality. The main mineral of soils derived from serpentine rooks is smectite (sapponite) and with less quantity of serpentine.According to the chemical analysis conducted it was observed that there is no smectite mineral in source rocks, thus the source of smectite in soil is neoformation. Soil reaction (pH) varies from 8.2-8.6 and therefore it is alkali. The reason of alkali pH is high concentration of Ni and Mg in soil solution. The amount of Cr in the bed rocks and soil consist of variable amount from 1362 to 2300 ppm in serpentine and 700 to 1900 ppm for soil matrix. The amount of Co in parent rocks varies from 80-185 ppm and for soil matrix from 98-270 ppm respectively. The amount of Ni varies from 1600-2692 and 1800-2850 ppn for mentioned rocks and soil matrix respectively. The amount of Ni increase with depth but there is not significant correlation between of Cr and Co with soil depth. Addition-Reduction percentage of different elements during soil formation show that amount of SiO2, FeO and MgO are less in soils in contrast to the bed rocks and the amount of Al2O3, CaO have a increasing rate for formed soil. The ratio of Ca/Mg in soil solution varies from 0.2-0.89 and 0.18 to 0.67 for affected water. The low ratio of Ca:Mg are caused bittering of water. The amount of available K and calcite in soils is low, ECe is lees than 1 dsm-1, Soil texture is sandyloam to loamysand with large amount of residual gravells. According to stability of serpentine the most of soil samples are seems to be unstable.

In order to investigate the interaction effect between different levels of irrigation water and nitrogen on Falat wheat yield, an experiment with split plot design consisting twelve treatments replicated 3 times over 3 years (1993-1994 to 1995-1996) was conducted in Zarghan area in Fars province. The main and sub plots devoted to the amount of irrigation water in 3 levels (E1 = 30, E2 = 60 and E3 = 90 % of available water depletion of root depth) and nitrogen levels in 4 levels (N1 = 90, N2 = 135, N3 = 180 and N4 = 220 kg ha-1), respectively. The results showed that the effect of irrigation water and nitrogen levels on yield was significant at 1 % level, but the interaction effect between different levels of irrigation water and nitrogen was not significant. However, the comparison between mean of twelve treatments with Duncan method showed that the results were significant, and the maximize and minimize yields was 6747 and 3852 kg ha-1 in E1N2 and E3N1 treatments, respectively.

Using the given method by SCS to examine the effects of abstraction of rainfall on soil and how to form flood hydrograph for hydrulic structure is the main subject of this research. In this field, climatic factors as severe rainfall have been applied and related physical factors and soil vegetative cover have also important role to change rainfall into run off and have been analyzed in a specific geographical zone Bagh malek watershed basin. One of the major methods used to examine the way of forming run off because of rainfall on the earth, is a common method of (SCS). On the whole, this method considers the conditions of soil and its vegetative cover to change rainfall into run off. In this study, the results of estimation in the filed of changing rainfall into excess rainfall has been studied as curve number (CN) by using 2 different methods estimating CN has been documented with soil’s characteristics and surface vegetative cover and another method accompanied by observations and hydrulic conditions related to flood which is an estimation of CN method and has been analyzed. On one hand, the process of forming run off using SCS method and estimation of excess rainfall of hydrographs has been studied and compared. Existing difference in the process of estimation and observation of run off has also been examined. By using the phenomenon of “rainfall-flood” some observations have been performed for the calibration of HEC-HMS model, by which curve number (CN) has been estimated. The results of estimation of CN method by the mentioned model is compatible with those of observed CN.

In order to study genetic variation of rice genotypes in Fars province, 100 lines of rice genotypes including some new experimental genotypes of Fars province were evaluated. The experiment was performed based on triple lattice design in agricultural research center of Shiraz University at kushkak in 2001. The analysis of variance showed a significant difference for six traits of one thousand seed weight, seed number in panicle, number of fertile tiller, number of sterile florets in panicle, plant height and the yield of single plant between genotypes. Mean comparison showed that some lines from the gene bank are better based on their yields and some other traits. Standardized data were used in cluster analysis using six methods by SPSS package. The ward's and the furthest method showed the best classifications. Nearly both methods created similar clusters. Different groups show genetic variation in rice genotypes on the basis of morphological traits and this guide us to select the most different and the best of them for hybridization programs, especially to hybridize with local varieties of Fars province.

In order to study correlations between traits and its analysis to cause and effect relationships in rapeseed plant, an experiment was conducted by a Randomized complete block design with three replications for fall rapeseed 15 cultivars in 1381-82 years at khorassan agricultural research station. Evaluation and analyze for important 11 traits in statistical analysis. Results analysis of variance is shown that between cultivars for all traits there is significant diference through statistic. Simple correlation coefficient is significant between yield and number of pods per plant, harvest index, oil percent, stems diameter number of secondary branch per plant and biological yield traits at 1 percent level. According to stepwise regression seed yield trait is considered by dependent variable and number of pods per plant, number of grains per pod, one 1000-grain weight, number of nodes per stem and oil percent traits by independent variables. Model determination coefficient is R2=0.64. The most of determination coefficient R2=0.41 there was for number of pods per plant trait. Path coefficients analysis showed that highest direct effect of number of pods per plant relation to another trait affected the grain yield. Number of pods per plant had negative indirect effect through number of grain per pods, one 1000-grain weight and number of nodes per stem order to –0.016, -0.094, -0.094 on grain yield. Positive direct effects of number of grain per pods and one 1000-grain weight on grain yield were canceled by negative indirect effects and caused that correlation reduces between this traits and grain yield. Principal component analysis and cluster analysis was confirmed above results. Therefore the most important traits order to selection index for grain yield improvement were number of pods per plant, number of grains per pod, one 1000-grain weight and number of nodes per stem.

In order to study the genetic variation in cultivated diploid cotton landraces, 9 landraces from G. herbaceum species and 1 landrace from G.arboreum species evaluated in Kashmar Cotton Research Station in 2002. Landraces showed high variation for 12 morphological and quantitative traits, after analysis of variance and classify means by Duncan’s Multiple Range Test. For seed cotton yield landraces Sorkhesemnan and Aria had highest yield (1617 and 1593.7 Kg/hac respectively), landraces Baharanemehriz and Banafshekerman had lowest yield (476.5 and 449.1 Kg/hac respectively). Clustering of landraces was done by Cluster Analysis and Principal Component Analysis (PCA) methods. Both methods showed the same results for grouping landraces.

This research was done for studying the influences of plant density on the three cotton cultivars at Karkandeh research station of cotton, Kordkoy, Gorgan in 1378 and 1379. The experiments were conducted in a randomized completely block design as split-split plot with four replications with cultivars (Sahel, Siokra324 and Zeta-2) as main plot, row spacing (80 and 100 cm) as sub plot and plant distance (10, 20 and 30 cm) as sub-sub plot. In all the treatment, plant height, monopidal branch length, number of monopidal and sympodial branch, the number of boll, the weight of the boll and yield were measured. The results showed that Siokra324 has more yield by having more boll in plant than two other cultivars. This cultivar produced 400-600 kg/ha yields more than Sahel and 200-500 kg/ha yields more than Zeta-2. In each three cultivars, the highest yield in high population densities was got, that highest yield in Sahel was got in and 125000 plant per hector and Siokra 324 was got in 62500 and 125000 plant per hector and Zeta-2 was got in 125000 plant per hector. It is advised that the complemerstary experiments is done on population density more than 125000 plant per hector and narrow row spacing and compact cultivras form in some years and places and it is advised too, that the factors such as the percentage of canopy covering, leaf area index, fraction of incoming solar intercept by the canopy and radiation-use efficiency and water-use efficiency will measured.

In order to investigation of GA3 and Kinetin effects on germination parameters and seedling growth of wheat (Triticum aestivum cv. Flat) under salinity stress, we conducted a factorial experiment design with 4 levels of GA3 (0, 1.5, 3 & 4.5 mg lit-1) and Kinetin (0, 1, 2 & 4 mg lit-1) at 4 levels of salinity that prepared by 0, 70, 140 & 210 mMole NaCl. ANOVA of studied traits at germination and seedling growth phases showed that germination percentage, seed germination and seedling growth rate, root and shoot length decreased dramatically by increasing of salinity. Increasing of exogenous GA3 concentration led to increasing of shoot length and water tissue content at different levels of salinity but it had an inhibitory effect on germination rate. The high concentration of Kinetin (mg lit-1) led to increasing of shot length and shoot/root ratio seriously. There were interaction between GA3 and Kinetin in related to seedling growth parameters at salinity levels. GA3 and Kinetin treating increased seedling water content. Se of this experiment results and development of researches in related to exogenous application of plant growth regulators can be lead to better understanding about physiological mechanisms of plant tolerance to environmental stresses.

The velation between crop yield and air temperature during growth stage, can be evaluated in different ways. Growth and development rate, dry mather production, quality and quantity of yield are the important factors for screening genotypes of plant species like wheat and rapeseed that grown in cold region of Iran as a winter crops. It is a long time that means of delay temperature and physiological base temperature (GDD) used for determine of interaction effects between environmental temperature and crop yields in the several of studies. This study to have an intention use the other temperature index for screening of winter rappelled varieties under different cold temperature under the technical term Chilling degree-days (CDD). The sum of minimum daily temperature below zero during the rosette stage of rapeseeds at four cold region of Iran (karaj, zanjan, hamedan and shahre-kord) is a criterion for quantified of cold temperature days, cold acclimation of winter rapeseeds and Growth and development rate, dry matter productions, quality and quantity of yield.

This experiment was conducted to evaluate the effects of plant density on grain yield of corn cultivars in Jiroft area from 2002- 2004. Experimental design was as split plot based on Randomized Complete Block with three Replications. The main plots were four density levels (5.5- 6.5- 7.5- 8.5 plant/m2) and subplots were four cultivar levels (S.C 704- T. W. C 647- S.C 700, S.C 720). 2 years results showed that increasing of plant density increased yield so the highest yield (18.46 t/ha) obtained from 8.5 plant/m2 in contrast to other treatments. As a whole the highest yield (19.88 t/ha) obtained from 720 cultivar and 8.5 plant/m2 density that wasn't different significantly with some cultivars in density of 7.5 plant /m2. The 700 karaj hybrid with plant density of 8.5 plant/ m2 (yield 19.51 t/ha) is recommended for the Jiroft region n.

Effects of different levels of sulfur and pyridoxine on the microbial protein synthesis were studied under in vitro and in vivo conditions. In the first experimen (in vitro) rumen fluid was taken from the fistulated lambs and used to prepared a culture medium contianed of rumen fluid; 100 ml, starch; 500 mg, cellulose; 500 mg and urea; 64.4 mg and different level of sulfure (0, 1, 2, 3 mg/ 100 ml) and sulfur plus pyridoxine (1 + 0.01, 2 + 0.1, 3 + 1 mg/ 100 ml). The cultures incubated for five periods; (0, 2, 6, 12, 24 h) at 39.c. The experiment was performed as a randomized complete block design. The highest microbial crude protein synthesis was with N: S ratio of 10:1 and the sulfur of 2 mg/100 ml as well as the sulfur plus pyridoxine were 2 mg + 0.1 mg/ 100 ml of incubated cultures. In the second trial (in vivo) that was performed as a change over design used four male lambs with an average weight of (35 ± 3 kg) were used. The animals fed for eight period with seven diets including different levels of sulfur (0.12, 0.16, 0.22, 0.38 % DM) and sulfur plus pyridoxine (0.16+11.8, 0.22 + 51.8, 0.38 + 101.8 % and mg/ kg DM). The treatment diets were isocaloric and isonitrogenous.The highest values of microbial protein synthesis were in the diets containing 0.22 % S and 0.22 % S + 51.8 mg/ kg DM B6). However the highest purine nitrogen index and blood proteins was in diet including (0.22 % S + 51.8 mg/ kg DM B6).It was concluded that improvement in microbial nitrogen synthesis May occure with N: S ratio of 10: 1 and the addition of pyridoxine in ruminant ration may also enhance the parameter.

This study was conducted to investigate the effect of energy level in short-term on gonadotrophins secretion and ovulation rate in fat-tailed ewes. Sixteen Chal cyclic ewes (2.5 years of age) were selected and received 250 mg Cloprostenol in -11 d and 0 d of the experiment period. Ewes were assigned in two groups (n=8) and received following treatments for 4 days. Ewes in group I were fed a diet providing 180% of maintenance energy requirement and ewes in group II were fed a diet providing 100% of maintenance energy requirement. For blood sampling (3 ml) three ewes were selected. Blood samples were collected at 20 minutes and hourly intervals for 3 hours in day 0, 2, 4 and 5 to determine secretary pattern of LH and FSH, respectively. After the treatment period, body weight (BW), body condition score (BCS) and ovulation rate (OR) were determined. BW, BCS And OR did not have any significant differences between two groups. Increase of energy intake did not affect significantly mean plasma concentration of FSH and LH, and LH pulse frequency and amplitude. Results indicated that ovulation rate and gonadotrophins secretion pattern in fat-tail Chal ewes did not respond easily to energy changes.

In this research, height effects on beach wood’s oven dry specific granity and for telling ahead how to make the beach wood easy to use. In order to, three site chosen in a geographical area “Shenrooad Siahkal forests” with three different height from sea level which are 700, 1000, and 1400 meters; moreover, property of each area were processed and they include of soil properties, geographical situation, down hill percentage, and weather condition. In each height, 10 samples have gotten increment borer as height as chest, and those 10 samples were sent to laboratory for being exam. As a result of property biometry the beach wood have fiber length, fiber diameter, lumen diameter, two wall thickness, and oven dry density were measured, and slenderness ratio, flexibility ratio, and rankle ratio were inspected. The result of research showed that fiber length, and oven dry density with increased height from sea level decreased properly, but fiber diameter, and lumen diameter were decreased irregularly with increase height from sea level. Lumen diameter within height of 1000, and 1400 meter did not have the difference signification with each other. The wall thickness with increase height was increased properly from sea level; although, within height of 700, and 1000 meter did not have the difference signification. Slenderness ratio and flexibility ratio were decreased properly with increase height from sea level, but rankle ratio was increased properly with increase height from sea level.

This research with purpose to distinguish properties of Pulping and Paper making from stem of colza (Brassica napus) and capability of Semi-chemical Pulping was performed. The exception was Type selection of used tests was Ocapie that was prepared from center of modification of seeds, karaj county and transferred to the Mazandaran Pulp and Paper mill. In Conditions of Cooking process, were two different chemicals consumption (chemical charge) 10% and 20 % on the (basis of dry) colza weight and periods of digestion were 30 and 40 minutes and the condition of pulping was 170 degree of centigrade temperature. Using PFImill,four kinds of pulps with four different freeness were made up to 410±25 CSF by PFI mill refiner. Then seven hand sheet 127gr/m² were made measured. For study the resistant properties of hand sheet papers, used the TAPPI standard, study on mechanical strength of handsheets showed that when the yield decreased, the resistance index of paper like that: Tensile Strength, Ring crush Test (RCT), Burst Strength, Burst Strength, Stiffness, Strage, Breaking Length Corrugated Medium Test was increased.

Walnut wood (Juglans regia L.) is numerate one of durable woods which is formed to disperse trees figure, one of industry woody species and valuables our country, specially in north of Iran (Ramsar’s forest). Extraction of heartwood extractives this species were done on basis T204-OS-76 standard by soxhlet extraction using ethanol/toluene solvent. The percent average of walnut heartwood extractives was determined ten percent. Identification of chemical compounds in the extractives samples were done by using GC/MS technique. Generally, thirteen compounds were identified which there is with different percent in heartwood. The most abundant compound identified in heartwood of walnut species was benzoic acid, 3,4,5- tris (trimethylsiloxy) (Gallic acid) amounting to 44.57%. The most important identified organic acids in heartwood of this species were propanoic acid, 2-(trimethylsiloxy), trimethyl (1.07%), benzoic acid, 3,4-bis (trimethylsiloxy) (2.06%). The most toxic identified compounds, was Juglone (5.15%) and 2,7- dimethyle phenanthrene (5.81%).