فهرست مطالب دادگر محمدی

In this research, effects of water sprayed over the upper layer of the mowed and rowed alfalfa (before baling) on quantitative and qualitative losses of alfalfa during baling process were evaluated. The study was conducted in the form of split plot experiment with 12 treatments and three replications from 2020 to 2022. Main plots were the amount of water sprayed on the alfalfa with four levels of water (0, 250, 350, and 450 liters per hectare). Subplots were the time interval between spraying water on alfalfa and baling operation (0, 30, and 60 minutes after spraying water). Alfalfa losses at the baler pickup and compression chamber, during transportation, and total losses were measured. Alfalfa dry matter, crude protein, fat, organic matter, ash, acid detergent fiber, neutral detergent fiber was measured, and amount of aflatoxin were also detected after six months of storage. Results showed that spraying 450 L water per hectare decreased alfalfa losses at baler pickup and compression chamber, transportation, and total losses by 20.4, 34.3, 4.7, and 21.1% respectively, compared to the control treatment. Time interval between spraying water on alfalfa and baling time had no significant effect on alfalfa losses during baling operation and transportation. Results also indicated that spraying water on alfalfa before baling operation had no significant negative effects on alfalfa quality after six months storing and did not reduce alfalfa quality during storing time.

The use of mechanical methods for weed control with suitable cultivators increases yield, reduces labor costs, and ultimately enhances income in cotton fields. This research focuses on the construction and evaluation of an in-row cultivator machine (for controlling weeds both between and within rows) and compares it with the conventional method of weed control using a sweep cultivator and a chemical control method in cotton planting.

The experiment was conducted as randomized complete block design (RCBD) with eight treatments and three replications at Darab Agricultural Research Station in Fars province. Test treatments were using in-row cultivator and trifluralin herbicide before planting (T1), sweep cultivator and trifluralin herbicide before planting (T2), in-row cultivator and trifluralin herbicide afte planting (T3), sweep cultivator and trifluralin herbicide after planting (T4), in-row cultivator (T5), envok herbicide (T6), full-season control of weeds (T7) and no weed control (T8). The cotton planting operation was done with Golestan seeds and in the amount of 20 kg/ha with a pneumatic planter. The consumption rate of trifluralin and envok herbicides was considered 2.5 lit/ha and 15 gr/ha, respectively. The parameters of weed control, soiling of plant, yield and yield components were measured and economical evaluation was done.

Maximum weed control (92.78%) was achieved using the in-row cultivator and trifluralin herbicide before planting, which did not differ significantly from the full-season manual control treatment. The use of a sweep cultivator increased plant soiling by 67.4%. Results also indicated that applying trifluralin herbicide before planting resulted in higher cotton yields compared to applying it after planting in conjunction with the in-row cultivator. Economic analysis revealed that the gross margin of using the in-row cultivator was about 67% higher than that of the conventional sweep cultivator.

The results of this experiment demonstrate the efficiency of the in-row cultivator compared to the sweep cultivator. This research shows that both mechanical and chemical weed control methods are effective in cotton cultivation. The in-row cultivator, a new method for controlling weeds in cotton fields, proves superior to the conventional sweep cultivator both technically and economically. In-row weed control with the in-row cultivator reduces labor and the traffic of tractors and agricultural machines, increases cotton yield, and is recommended for cotton-growing areas with row planting.

Given the significant share of chicken meat in the food basket of households, the fiull price and its changes are of financial importance for consumers and producers. In this study, based on the budget of poultry farming units in Fars province of Iran, the cost price of live broiler in different capacities, seasons and types of mechanization systems was calculated and its changes were investigated. Also, the indicators of input cost share, optimal production size, as well as self-price and cross elasticities were calculated by estimating the cost function. The data used were collected from 88 broiler units by random sampling method. The study results showed that the full price of live broiler in the winter season is higher than other seasons, and the decrease in the average price of chicken meat with the increase in production capacity indicated that the smaller the capacity of the farm, the more uneconomical the production becomes, and the use of more modern technology in poultry units would lead to an increase in fixed costs and the full price of the product; the value of cost elasticity in relation to production is on average around 0.876 and therefore, the production of live broiler in Fars province has an upward return to scale. In addition, by calculating the price elasticities, it was found that the input demand was inelastic to price changes and also, the values obtained from Morishma elasticity of substitution indicated the very limited power of choice of the province's poultry industry in substituting production factors with each other. Therefore, due to the low price in live broiler farms with higher capacity and the upward efficiency compared to the scale, it is necessary to plan for developing the units with higher production scales.

Separating the seeds from the cottonseed with a gin has an effect on seed quality and germination. Mechanical damage reduces the economic and biological value of the seeds. The effect of mechanical damage is considered a serious problem in seed production, and reducing this effect leads to an increase in the efficiency of seed utilization. This study was conducted with the aim of reducing the mechanical damage of cotton seed and increasing the efficiency of gin and rotating the saw and moisture content appropriately in two varieties of Hekmat and Golestan cotton seeds.

To increase gin efficiency, the effect of saw rotation in three levels, 300 (S1), 350 (S2) and 400 (S3) rpm, lint moisture content in three levels, 3-5% (M1), 6-8% (M2) and 8-10% (M3) and seed variety in two levels of Hekmat (V1) and Golestan (V2) varieties were studied in a factorial experiment in the form of a completely randomized design with three replicates. The parameters length, width, thickness, geometric mean, sphericity coefficient and bulk density of cotton seed were determined according to the relationship between the physical properties of the seed and the performance of the machine during processing. In addition, the parameters related to the gin, including the extent of mechanical damage to the seed, percentage of ginning and material capacity, were measured. The data were subjected to analysis of variance and the regression equation between the independent variables (experimental treatments) and the dependent variables (measurable parameters) was determined.

An increase in moisture content led to an increase in the geometric mean of the dimensions of the cotton varieties. The increase in mechanical damage to the seed also increased with the increase in moisture content from 6-8% to 8-10%. The main reason for this was the adhesion of the fibers to the cotton seeds and the increase in the time for separating the fibers from the seed. The results showed that increasing the moisture content from 3-5% to 6-8% increased the percentage of ginning operations and the material capacity of the gin in both Hekmat and Golestan varieties; however, as the moisture content increased to 8-10%, the extent of these parameters decreased.

Although pomegranate is one of the major horticultural products in Iran, little research has been done on its irrigation management. In order to investigate the effect of irrigation management on the yield and productivity of 'Rabab-Neyriz' pomegranate trees, an experiment was conducted in one of the pomegranate orchards of Kazerun city in Fars province. Experimental treatments included irrigation at different amounts of available soil moisture depletion at 35, 50, 65 and 80%. A treatment that was completely irrigated by the orchard owner was also considered as control. The experiment was performed in a randomized complete block design with three replications. Soil moisture was measured in different treatments with gypsum block moisture meter. After the soil moisture reached the desired limits, the required amount of irrigation was applied to bring the soil moisture to the field capacity. The orchard was equipped with drip irrigation system and the amount of irrigation water was measured by calibrated flow meters. The experiment was performed for two years and the amount of water used, the yield and water productivity in different treatments were estimated and evaluated by comparing the average values. By measuring the temperature of plant canopy and other required meteorological parameters, the upper and lower stress baselines were extracted by Idso method. Economic analysis was also performed by estimating cost and revenue. The results showed that with the increase of the total water to 19580 cubic meters per hectare (control), the amount of crop yield also increased to 36 tons per hectare, while at soil moisture depletion of 35%,the total used water was 10511 cubic meter and the yield was 28 tons per hectare.The total water productivity in different treatments varied from 1.82 to 3.08 kg / m3, which decreased with increasing the applied water. Differences in water productivity and yield between the 35 and 50% moisture depletion treatments were not statistically significant. Economically, the best treatment for irrigation was the 35% moisture depletion that according to the previous studies, it can be considered as the beginning of water stress in the pomegranate tree. The lower and upper stress baselines obtained in this study, which has not been reported in previous studies, can be used as a tool to manage the irrigation of pomegranate trees in the study area and other similar regions. Therefore, in general, the best treatment of experiment was irrigation at 35% soil moisture depletion. In low water areas up to 50% soil moisture depletion also brings good results.

This study was conducted at Darab Agricultural Research Station in wheat-cotton rotation for four years. A complete block experimental design with three treatments (no-till, reduced tillage, and conventional tillage methods) and four replications were used. Tillage methods were compared economically. The most beneficial treatment was selected based on estimating the costs and incomes of different treatments and using the net present value method of gross margin changes. Analytical hierarchy analysis (AHP) method was also used to select the most appropriate tillage method. Results showed that there was no significant difference between tillage methods for wheat and cotton yield during most of the years that this investigation was in processing. Reduced tillage and no-till methods decreased wheat and cotton production costs, compared to conventional tillage, for 5 and 10% respectively. These conservation tillage methods, compared to the conventional tillage, also reduced fuel consumption for 60 and 77%, respectively. Conservation tillage methods increased effective field capacity of seed bed preparation and planting operations, so that time required for seed bed preparation and planting operations decreased in reduced tillage and no-till, compared to the conventional tillage, for 62 and 74%, respectively. Conventional tillage had maximum present value of gross margin (53662 thousands Rials) compared to reduced tillage (46379 thousands Rials) and no-till (38149 thousands Rials). Considering different factors in decision making, parameters such as crop yield (0.312), production costs (0.221), and water consumption (0.219) had the highest weight in farmers’ decision for selecting tillage method, and the conservation tillage methods received the highest priority for selection.

Effect of conservation tillage on soil properties and crop yield may be influenced by climate condition, soil type, and crop type and rotation. Therefore, evaluation of different tillage methods in different climate conditions, soil textures, and crop rotations is necessary. In this research, the effect of conservation tillage methods on soil properties, cotton yield, and its economic efficiency was evaluated in wheat-cotton cropping system in arid climate condition of Fars province (Iran). The study was conducted in the form of a complete block experimental design with three treatments and four replications in Darab Agricultural Research Station for four years. The treatments were reduced tillage, no-tillage, and conventional tillage (control treatment). The results showed that the tillage method had significant effect on moisture retention in the soil so that the no-till and reduced tillage increased moisture retention in the soil compared to the conventional tillage by 15.22 and 5.47%, respectively. The tillage methods had no significant effect on the soil infiltration, soil aggregates, and cotton yield. Economic evaluation revealed that the conventional tillage had the highest economic efficiency followed by the reduced tillage and no-till. However, the economic returns of all treatments were positive. If a proper management be applied during replacing the conventional tillage with conservation tillage methods, the advantages of conservation tillage could be reached in cotton planting.

This study aimed at investigating the economic poverty of settled nomads and identifying its determinants in Fars province of Iran. Data gathering was carried out in 2013 through 175 questionnaires from settled nomad households in a two-stage cluster random sampling method . The headcount poverty and poverty gap indexes were used to determine the poverty situation, and Tobit model was used to determine the factors affecting the poverty probability. The results showed that 49.14 percent of households were suffering from poverty; nearly 60 percent of the poor households suffered from extreme poverty; and depth of their poverty was more than 70 percent. Based on the results, education level and age of household heads, agricultural activity level, household size and number of animals were affecting poverty probability for the households. Accordingly, focusing on adult education, strengthening complementary activities and concentrating on the overall population policies issued by the Iranian Supreme Leader were recommended within a sustainable approach to poverty alleviation in the centers for settled nomads.

In this study, the performance of different cultivation methods on sugar beet fields was evaluated. Eight treatments were considered: a) use of a rolling cultivator twice during the growing season; b) use of a rolling cultivator three times during the growing season; c) use of a crescent cultivator twice during the growing season; d) use of a crescent cultivator three times during the growing season; e) use of a furrower as a cultivator twice during the growing season; f) use of a furrower as a cultivator three times during the growing season; g) manual weed control twice during the growing season; and h) manual weed control three times during the growing season. A randomized complete block design with three replications was used in this research. Parameters such as sugar beet yield, percentage of sugar, sugar yield, percentage of sugar in molasses, weeds remaining in the field and nitrogen, potassium, and sodium content of the sugar beet root were measured for each treatment. Results show that there was no significant difference between the treatments for sugar beet yield, percentage of sugar, percentage of sugar in molasses, and nitrogen and potassium content of the sugar beet root. The difference between treatments was significant for weed weight remaining in the field, sugar yield, and nitrogen and sodium content of the sugar beet root. Of thetreatments tested, manual weed control three times during the growing season showed the best performance for weed control and use of a furrower as a cultivator twice during the growing season produced the poorest performance. Use of a rolling cultivator three times was the most economic of the methods tested.