Year:2007 | Volume:13 | Issue:1|Papers Count:25

Date is one of the most important hourticulture poroduction which enumerated as main source for energy supply and human nutrition for long time. Iran is one of the largest producers of date in the world. At this study, it was investigated on the situation of Iranian date export at last years (1970-2003) and it was estimated function of export supply for date and it was determined instability of income for date export. From obtained results, it was showed that on the basis of RCA index during the studied time, strategy of date exports in Iran was the weaker than Iraq, Tunisia, Arabia and Algeria, or do not exist any strategy in export of date. Instability of the Iranian date export equaled 25.4 that it was showed high fluctuation of date export income in this studied period.

Non-oil export is one of the most important economic subjects in Iran. Increasing the share of non-oil export, as a main purpose, is under consideration in the economic development programmers. The export of agricultural products has an important role in the non-oil export. Pistachios and raisins are the principal traditional export products of Iran and, since ancient times, have always occupied a special position in the foreign trade of the country. The object of this study is to examine factors affecting Iran pistachios and raisins market shares in 3 importer countries. Therefore, the effects of Iran pistachios and raisins prices, exchange rate values, and their volatilities on Iran market shares in these countries are analyzed. In order to include the effects of competition between exporting countries (Iran, U.S. and Turkey), the variables are formatted as relative values. Data for the present study are Panel data. Regression analysis and OLS, GLS and SUR approaches are used for estimating the model and operating software is Econometric Views (Eviews). The results show that relative pistachios and raisins export prices and exchange rates are important factors affecting Iran market shares, implying that higher Iran prices and exchange rate values have detrimental effects on Iran market shares. Also, the variables of relative volatility of prices have negative effects, while relative volatility of currency values are not statistically significant. This implies that importers are sensitive to price volatility.

One of the most important dimensions of extension and educational program's evaluation is "evaluation of effectiveness". Hence, the purpose of this study was to assess the effectiveness of range management educational courses implemented by the Ministry of Jahad-e-Agriculture. The research design used was a correlative-descriptive method. The population of this study included two statistical groups. The test group was consisted of all participants in educational activities in Tuyserkan Township (N=130). A sample obtained through systematic sampling (n=100). Eighty numbers of This sample answered to the maikd questionnaires. In addition a simple randomized sample was drown from the control group, nonparticipants in educational activities (n=80). The Questionnaires were completed by interview. Face and content validity of the questionnaire was stablished using a panel of experts consisting of faculty in the Department of Agricultural and Extension Education at Tarbiat Modaress university and Extension officers and natural resources experts. The questionnaire was field-tested. Reliability analysis for Alfa Coronbakh's value was being reported to be 81 percent Results indicated that there is significant difference between knowledge and awareness of Groups. Also educational traits of these activities have been evaluated approximately appropriate. There is strong relationship between level of Participation to argue educational materials with satisfaction, and the most useful teaching method was practical method.

The role of education in enhancement and improvement of human resource competency and its role in productivity and production are known to all. This research has presented a model and ways to implement it in order to make both the secondary agriculture education system and the job market for the graduate students. compatible. This model will help to determine the job market expectation so the students can up to date and increase their productivity. The research method was a descriptive-correlation. Survey method was used to gather data. The population of this study included experts (38), executives (120), and secondary agricultural school graduates (210). Content and face validity of the instrument were established by a panel of experts consisting of faculty members and specialists in the field of secondary education. Instruments reliability was estimated by calculating Cronbach's alpha coefficient by SPSS/wind. Reliabilities of the instruments were 0.83 for experts, 0.87 executives, and 0.76 for graduate students. Data were collected through mailed questionnaires. The findings showed that students found activities such as student teaching, teacher training, use of laboratory equipments by students, and having practical as well as vocational type of subjects, and appropriate teaching methods used by educators can have a great significant role in enhancement of their practical work. From the viewpoints of experts, training skill worker, prioritizing rural students in the process of employment and exportation of agriculture goods identified as the most important aspects. From the view points of executives, employment of rural students in the field of agriculture, emphasis of practical and vocational subjects, competency of both academicals and specialist personnel, and the role of support and service groups in creation of jobs seemed to be important factors in the development of secondary agricultural education system.

IN this study for investigating on the quality and quantity of afforestation in Pardisan Eco-Park, with species such as Locust tree, Desert Ash, Tree of heaven, Arizona Cypress, Pine and Horizontal cypress has been afforestated. Inventory as systematic random sampling and with intensity of sampling 1.3 percent in statistical grid 100´150 meter and sample plots circle (2R) has been done. In quantitative study some factors such as diameter at breast height, crown diameter, tree height and crown height were measured and then diameter distribution histogram, height and height curve were drawn. Qualitative study involved of evaluation crown form, healthy crown, trunk form and alive percent. Data analyse in quantitative study were used with analysis of varience and Duncans test. The result of study showes that softwood species, especially Pine had most diameter and height increment and Locust tree specie had lowest increment.With concern of healthy crown, all of species have good condition as in hardwoods, Tree of heaven specie with 69.1 percent and in softwoods, Pine specie with 83.3 percent have most healthy crown range. With concern of alive crown Locust tree specie and Arizona Cypress with 89.9 percent have most alive range and Pine specie with 80 percent has lowest alive range.

A sensitivity analysis was done for soil water balance model for rain-fed vineyard in microcatchrnents in Bajgah area, Fars province. The objective of this study was determination of the effective and less effective of parameters. To do it, important parameters such as daily maximum and minimum temperature together, daily maximum and minimum relative humidity together, daily wind speed at 2 m above ground surface, daily sunshine, field capacity of each soil layers and wilting point together, readily water available coefficient and crop coefficient were considered and +I0 % and -10 % were added to them, separately.Then, the results of model estimation of volumetric soil water contents in depth of 120cm, and the amount of soil water at depths of 0-120cm were compared with the measured data. The results indicated that field capacity and crop coefficient were more sensitive and the other parameters that used for calculating reference crop potential evapotranspiration, had less sensitivity.

It is recommended to use the average daily crop evapotranspiration (ETc) to calculate the peak water requirement with proper probability level. In this case, crop will receive necessary water and it will prevent the water stress. The effecting factors on choosing probability level are soil texture, risk level accepted by farmers, and irrigation method. In this research, starting and ending dates of maximum water requirement period for crop patterns in agricultural lands under Alavian Dam, Maragheh, have been deternlined. Based on these dates, average daily ETc for periods of 1 to 30 day with different probability levels have been calculated. The results show that the differences in ETc in different probability levels are considerable and it can affect the design of irrigation system, significantly. In addition, it is possible to obtain the average daily ETc for peak water requirement period with selected probability level from calculated curves. The comparison with 10-day period with 50% probability level, which is a common procedure in irrigation system design, showed that crop can receive up to 25% less water in peak period. This stress for sensitive crops can significantly reduce the crop yield.

Drought is a natural disaster that influences on the all climates. Because of several reasons such as differences in water requirements in consumers systems, there is not a certain definition for drought. The kinds of drought are as follow: Meteorological, Hydrological and Agricultural drought. In, order to quantity evaluation of drought severity, drought indices is used. Up to now, no document study about Agricultural drought has been reported in Iran. Used indices apply for agricultural drought in the world is not sufficient. In this study, first a definition agricultural drought in the basis of relative yield was suggested and the definition was applied to evaluation of agricultural drought. This index determines agricultural drought severity, comparing relative yield with its long-term average. By testing of this index, agricultural drought severity during last 30 years in Tabriz region for dry farming of wheat was determined. In order to simulation of relative yield in previous years, Doorenbos and Kassam model was used. SIMPLE model was used for determination of actual evapotranspiration which is among input data of Doorenbos and Kassam model. For evaluation of SIMPLE model a field study was carried out. The results showed that, this model has a high accuracy in simulation of actual evapotranspiration. Also in this study the ability of Percent of Normal Precipitation (PNPI), Standard Index of Annual Precipitation (SIAP) and S indices for agricultural drought severity were studied and relationship between relative yield and precipitation distribution by using of multiregression in various stages of growth was reported.

To investigate the effects of winter wheat and legumes, as a rotation, and also the effect of fallow and different amount of manure application on success of winter wheat cultivation, in 1376 on experiment was conducted in Quazwin province, 90 km west of Tehran (altitude 1350 m, average precipitation 370 mm, average annual temperature 13.6CO).The land was laid fallow for the years 1371 and 1372, in the years 1373 to 1375 main plots were under winter wheat, manure, soybean and fallow; at the same tame with the cultivation of above mentioned crops in mentioned years, in subplots (0 and 5 tons) of manure were applied. In 1376 the field, which was under mentioned crop ration, a single cropping of winter wheat' was cultivated; where in a factorial experiment consisting of 2 factors (4x2) in a split plot design in 4 replications was carried out. The manure and rotation were positively significant, concerning the winter wheat yield and its yield components. In conventional crop rotation: winter wheat, fallow, soybean and manure: the yields in manure treatments were: 1860, 2579, 4080, and 4830 kg/ha respectively; and in plots without manure: 1490, 2090, 3130 and 4100 respectively. The results of this study showed, that the winter wheat yield in rotation with manure and soybean, and also with manure application brought considerably increased yields. Regression equations indicated strength relationship between the grain yield and soil Nitrate content.

In order to evaluation of effective trait on grain weight cultivars of wheat under drought stress, an experiment, complete randomized block design factorial with 4 replication in two site: Karaj and Torbat - e- jam with 9 different regime irrigation on 3 wheat varieties was conducted. Results showed that grain yield, grain effective filing period, maximum weight of grain and thousand grain weight in Karaj site were greater than Torbat-e-jam site. The effect of drought stress treatment was highly significant (p£0.01). As T1, treatment had the greatest yield, grain filling duration and the least grain growth rate, and T8 had the least yield and grain filling duration and the greatest grain growth rate. Drought stress conditions decreased grain-filling duration and increased grain growth rate. Results of correlation showed that seed yield is positively and significantly correlated with grain filling duration and, maximum weight of grain and negatively and significantly correlated with grain growth rate. Results of stepwise correlation showed that grain-filling duration is the most important trait in justification of final weight grain changes and after that, grain growth rate is another trait, which determines of final weight grain changes.

In order to survey the harvesting time and cutting hight on grain yield of rice ratoon in Taroom Hashemi variety, the experiment was done at splitplot in randomized complete block design with 3 repcation in sari city at 2003. The harvesting time and cetting haight have been shosen as main and suoplots, respectively. The main plot included 3 three levels (T1: the first harvesting in 23rd, Avg., T2 the second harvesting in 3 rd, sep. and T3 the third harvesting in 13th,sep) and subplot in five levels (H1 ground, level cutting, H2: 10 cm, cutting, H3: 20 cm cutting. H4: 30 cm, cutting and H5 : 40cm cutting). The grain yield in the first harvesting was more them the other times. It is because of inweasing some yield components like the total number of tillers and Fertilized tillers in each hill, the number of panicle per sq.m (m2) and the filled spikelets percentage. The grain yield was obtained at the manimum valve in cutting height 40 cm. It's reason is because of increasing the total number of spikelets per panicle. The manimum straw yield of this variety was related to the first harvesting time which is due to increase in the plant height and the number of the tillers in each hill. These characteristic mas also obtained at the manimum valve in the cutting height 40 cm, which is because of increase in the plant height, The manimum biological yield and harvesting index were obtained at the first harvesting time and cutting height 40 cm. So, it can be concluded that to produce more yield of rice ratoom, the higher cutting hight must be considered and the main plant must be harvested as soon as possible.

In order to study the effects of mechanical and chemical methods of weed control and their combinations on the grain and oil yield of Canola cv. Hayola, a field experiment was conducted during 2001-2. The experiment designed as a randomized complete block with three replications. Treatments were consist of eleven combinations of mechanical (using cultivator) and chemical control with Trifloralin and Setoxydim herbicides (pre- sowing and post-emergence herbicides, respectively). Results indicated that the highest weeds control, grain and oil yield obtains in treatment with tow times application of cultivator plus Trifloralin and Setoxydim herbicides. The highest grain yield in this treatment was due to highest pod per plant, grain per pod and lateral branches. Althoughthe highest grain yield was in treatment with two times application of cultivator plus trifloralin and Setoxydim herbicides, but the deference between this Treatment with two times application of cultivator plus Trifloralin and Setoxydim herbicides was not significant.

In order to study the effects of redroot pigweed interference in sunflower, Azarghol hybrid, this research was carried out in research station of Islamic Azad University of Tabriz at 2004, with three different weed densities (Dw) of 8.3,25 and 41.7 plants/m-2  and three interference times (Iw) of emerging with sunflower and 15 and 30 days after sunflower emergence in a 15-cm both side of the sunflower rows. The experiment was established as a randomized complete blocks design in a factorial arrangement with three replications. Analysis of variance indicated that difference between treatments due to influence on stem height at the flowering stage, disk diameter, seed number in each disk, hollow seed percentage, 1000 seeds weight, grain yield, seed oil percentage and oil yield were significant. The lowest and highest hollow seed percentage obtained from d5i30 and d25i0 treatments respectively. The highest 1000 seeds weight and grain yield obtained from density of 8.3 plants/m-2 and interference time of 30 days after sunflower emergence. Seed oil percentage increased in three treatments of 8.3 plants/m-2 in difference interference times in comparison with control. It seems that, redroot density has higher effect than weed interference time on seed oil percentage. Yield loss is affected more by interference time than by density.

Salinity stress is a serious threat of plant growth and production all over the world. SO there is a possibility of .cultivar diversity use in desirable traits selection under stress .this experiment for to identify selection indicats in barley under salinity stress was conducted .the present research as a RCBD design with 4 replications in two environmental of normal and salinity stress was designed. In this experiment 10 improved genotypes were used. Analysis of variance showed as significant different for the most of traits and most of them decreased under stress conditions. But the most decrease were observed in grain yield, biologic yield, plant height and leaf area index. finally, the correlation between the remaining characters in the model was divided into direct and indirect effect by path analysis. The results derived from correlation and path analysis indicated that in normal condition kernel number per head with a direct 0.709 and in the salinity environment spikelet number per spike with a direct 0.161 was the greatest factor affecting kernel yield.

To study the effect of physical forms (pellet and mash) of common iranian ration on performance of Arian hybrids, an experiment was conducted in factorial arrangement (2 sexes x 2 ration forms) in complete randomized design with 4 treatments and 5 replication each with 27 chickens for 49 days. Weight gain, feed consumption, feed conversion ratio, percentage of mortality, abdominal fat, carcass efficiency and body uniformity at the end of 7 week period were Compaired statistically. Average weight gain was significant between sexes, type of ration, but was not significant between sexes x ration. The average feed consumption was significant between sexes, type of ration, but was not significant between sexes x ration. Feed conversion ratio was significant between type of ration, sexes, but was not significant between sexes x ration. The average percentage of mortality was significant between type of ration, but was not significant between sexes x ration. The average percentage of abdominal fat was significant between sexes, but was not significant between type of ration and sexes x ration. The average percentage of body unifonnity was significant between sexes and sexes x ration form, but was not significant between type of ration. The average percentage of carcass efficiency was not significant among treatments and their intraction. It was concluded that feed consumption and weight gain of pellet form ration is more than of mash form and causes better feed conversion ratio for pellet form. The feed consumption in males was higher than females and causes better weight gain in males than females, so feed conversion ratio in males was better than females. In spite of this results, average percentage of mortality, carcass efficiency and body uniformity was better with consumption of mash form of ration.

This study was under taken to find out affecting of age and sex on wool quality of Lori sheep breed. in the first research, 192 wool sample of sheep were collected at shearing season in Lorstan province. Sheep were selected under uniform condition of management from flock of Lori sheep. The shearing was taken for these animals to determine body weight on the time of shearing, fleece weight, staple length, fiber diameter, fleece fat and cleaned wool yield in Lori sheep breed. An age of animals was among 1to 4 years. The statistical analysis of data was carried out with factorial experiment basis on completely randomized design combined with two factor age and sex over two years. The body weight on the time of shearing was covariate variable. The mean of fleece weight, staple length, fiber diameter, cleaned wool, greasy fleece were 2.21±0.22kg, 9.47±1.75cm, 31.67±4.19 micron, 72.51%±8.91% respectively. The investigation indicated that the mean of fleece weight and staple length were more in female and cleaned wool yield was in male more percentage. Effect of age and sex were measured on five parameters. Effect of year on staple length and interaction effect between sex and age on fiber diameter were significance. According to this investigation an increasing in the diameter was observed with the advance age. The results indicated that Lori sheep wool has to tender relatively comparison with the other native sheep breeds of Iran.

The propose of this research is evaluation of hull-less barley as an energy source in poultry nutrition with and without enzyme, In this study 2 kinds of barley (common barley and hull-less barley) after chemical analysis supplemented with 4 b-glucanase levels (0, 0,5, 1, 1.5 grams per kilogram grain) in 5 replications for each groups in a factorial arrangement in a Completely Randomized Design were used. In each replicate one leghom rooster in the age of 22 week was force-fed with a 30-gram sample and AME, AMEn, TME and TMEn were measured by Sibbald method. Comparing means by Duncan two-way analysis showed: the effect of barley kind, enzyme level and interaction between barley kind and enzyme level was significant (p<0.05). So that enzyme usage with hull-less barley has more beneficial effect than common barley. Suitable b-glucanase level for hull-less barley was 1 gram (equally 5600 unit activity) per kilogram but in common barley suitable level was 1.5 grams (equally 8400 unit activity) per kilogram.

In this research, effect of freeness on mechanical properties of papers made from colza with three different freeness was performed. Type selection of used was prepared from center of modification of seeds, karaj county and transferred to the Mazandaran Pulp and Paper mill. Best choice of condition of pulping was 170 degree of centigrade temperature and 20% chemical consumption and period of digestion was 40 minutes. And than by using PFI mill, three kind of pulps with three different freeness were produced from the proper pulp and then, 127gr/m2 hand sheet papers produced from different samples of pulps and their strength properties were measured study of mechanical strength of hand sheets showed that the beating has effect on tear strength and reduces this strength with more beating when the refining increased, the resistance indexes of paper such as ring corrugated medium test (CMT), ring crush test (RCT), stiffness; and other strength was increased the only exception was tear strength that decreased. With regard to reduces of tear strength that no important for linear boeard and increases ring crush test (RCT) and curugated medium test (CMT) and stiffness and other strength resulted pulps with 300±25 (CSF)is recommended.

Mazandaran province forests with an exclusive environmental ecological feature, have been considered as one of the important poles of wood production. Among 4 natural resources general offices of north forests, 2 general offices have located in mazandaran province which have the responsibility for exploiting the province forests, Products which are produced by exploiters include dressing trace log, timber woods, Cross tie, pillar and tunnel woods, cuttin, and firewood and charcoal. Gathering wood from the province forests has been reviewed during a 10-years period, Except of Cross tie products, timber woods and charcoal, in other cases products, we observe a meaningful difference between the products of sari s natural resources general office area the products of Noshahr s natural resources general office area. Fore example, from all forests of mazandaran province, about 541795 Hrs are commercial and industrial and production- worthy. Out of this amount, about (almost) 381795 Hrs has located in sari area and about 160000 Hrs has located in Noshahr area (district) which consequently (as a result) has been caused the amount of exploiting and producing a variety (different kinds) of forest products in Sari area shall be more than Noshahr area (district) in any way. The kind of forests and topography conditions of district has also a high impact (effect) exploiting amount in Noshahr district, because much forests of this area (district) are protective kind and natural resources general office of this district (area) doesn't allow executives to exploit and also because mach trees of production- worthy have located in heights with high slope and they make difficult exploiting conditions, and the production of a variety (different kinds) of forest products decreases considerably.

Boom equipped tractor mounted sprayer model TF400, is one of the conventional sprayers in Iran. It is employed in many parts of the country to spray the fields of wheat, barley, potato, corn and many other crops as well as rangelands. Having in mind the importance of environment protection as regards rational use of pesticides along with a consideration of production costs, a study together with an evaluation of this equipment is indispensable to find out the most important parameters effective in its proper operatioJ1. Therefore, in this study, the sprayer undergoes a computerized analysis and simulation to obtain a mathematical model governing the fluid (pesticide) flow as well as the systems components. Towards this end, the equations governing the fluid flow from the diaphragm pump's inlet to fan shape spraying nozzles are initially presented. These non linear differential equations are solved through MATLAB software. Then a computerized simulation of the sprayer dynamic behavior, is presented by use of SIMULINK simulation toolbox. To verify the mathematical model of the system, the sprayer was laboratory tested as follows: Pesticide fluid pressure was measured in two parts of the sprayer in 14 different operating conditions to obtain the real dynamic response of the system. The mathematical model was finally verified considering the fact that there existed a close match between the results obtained from laboratory tests and these obtained from computerized simulation.