An experiment was conducted as a split - split plot in form of a randomized block design with four replications in Cilakhor region of Iran in 2004. The main factor was the seed planting date with three levels (5, 12 and 25 April), sub factor was the crop density with two levels (160,000 and 250,000 pI/ha) and sub-sub factor was the crop arrangement with two levels (equidistant and non-equidistant). Delaying the planting date caused the increase of biological yield and decrease of harvest index. Increasing the crop density caused the increase of the number of fertile heads per square meter, biological yield, grain yield, and decrease of the number of fertile tillers, the number of grains per head, dry weight of above-ground organs per hill, yield of each hill (P<0.05) and the plant height, the number of grains per head was decreased.

In this research, the effects of the planting arrangement on the seed yield, its components, seed oil percentage and certain agronomic properties of safflower (Carthamus tinctorius L.) in Gogan (Located in East Azarbaijan Province) during 2002-2003 were studied. The space between rows was 15, 30, 60 centimeters and the distances between the plants in a row were 5, 10, 15 centimeters, respectively. Genotypes were IL111, Kj818 and Arak-2811. The experiment was factorial based on randomized complete block design with three replications. During the growing season different characters such as plant height, number of branches per plant, number of capitulums per plant, number of the seeds per capitulum, seed yield, harvest index, 1000 seed weight, and seed oil percentage were measured. Analysis of variance showed significant differences among genotypes for number of the seeds per capitulum, number of capitula per plant, 1000 seed weight, plant height and seed yield. The planting arrangement had significant effect on number of capitulum per plant, number of seed per capitulum, and seed yield. The plant spaling of 15 cm within row resulted in the highest yield. Arak-2811 with 4.34 tons of seed yieldlha was the highest yielding genotype. It seems that extending safflower cultivation to medium and poor soils of localities near Ourmieh Lake (e.g. Gogan) will be useful for obtaining an acceptable yield.

Effects of the planting arrangement on the yield, its components, seed oil percentage and certain agricultural properties of safflower (Carthamus tinctorius L.) were studied in Gogan (located in east Azarbayjan) during 1381 – 82. The space between rows were 15, 30, 60 centimeters and the distances between the plants were 5, 10, 15 centimeters and Genotypes involved IL111, Kj818 and Arak-2811. The experiment was done based on factorial with randomized block design in 3 replications. During the experiment different properties were studied including plant height, the number branch in plant, number of bolls, number of the seeds in a boll, seed yield , harvest index, thousand seed weight and seed oil persent. Analysis of variance showed significant differences among genotypes in number of the seed in capitulum, number of capitula in the plant, thousand seed weight, plant height and seed yield. At the same time the planting arrangement had significat effect on number of capitulum in the plant, number of seed in a capitulum and seed yield. The 15 cm resulted in the highest yield. It can be said that the Arak-2811 with 4/34 ton seed yield/ha was the best. It seems that, development of this plant is of great value especially in medium and poor soils of Ourmieh Lake edges (e.g. Gogan) to obtain an acceptable production.

To determine the optimum sowing and sowing pattern of sunflower (Azargol cultivar), an experiment was conducted at Agriculture Research Station of Uremia, Iran during 2005-2006. A split-plot design based on randomized complete blocks with four replications was used. The main factor involved three row distances (45, 60 and 75 cm) and the subplot factor involved four plant distances on the row (15, 20, 25 and 30 cm). The results indicated that the space between the rows had significant effect on grain yield, head diameter, weight of 1000 seeds, number of seeds per head, percentage of hollow grains and number of rings per head. Furthermore, seeds per head, 1000 seed weight, head diameter, percentage of hollow grains and rings per head were significantly affected by the within-row distances. There was also a significant interaction of row space×plant distance on row for grain yield. Based on these results, regarding grain yield, sowing pattern of 75×25 was recommended for sunflower cultivation in Uremia and similar regions.

In order to investigate the effect of planting arrangement on lodging and yield in rice cultivars, a split plot experiment based on randomized complete blocks design was conducted in four replications. The main plot was five rice cultivars (Tarom Mahalli, Tarom Hashemi, Tarom Deylamani, Tarom Langrudi and Sang Tarom) and three plant density (40, 80, 120 plant. M-2) were design as sub-plot. The lowest total spikelet’ s and sterile spikelet’ s were obtained in Tarom Langrudi and the lowest tiller number per hill and panicle number. m-2 were produced in Tarom Mahalli and Sang Tarom, respectively. Shortest length of first, second and third internode and biggest third internode diameter and also the least plant height were obtained in Tarom Langrudi. As a result the most lodging resistance and the least lodging index for third and fourth internode were produced in Tarom Langrudi. Total tiller numbers were decreased with increasing of plant density but in this case the panicles numbers were increased significantly. Node number, the length first, second internodes, the fourth internode diameter and also the third, fourth internode bending movement were decreased with increasing plant density. Minimum lodging index in the third and fourth internodes were produced in 80 plants per m2. Interaction of variety and planting density had significant effect on all agronomical traits and morphological characteristics that related to lodging traits. Therefore, there were significant differences between different rice cultivars in different planting arrangement.

To study the effect of planting arrangement on quantitative and qualitative properties of cotton (cv.Sahel) under intercropping with berseem clover (cv. Carmel), an experiment was conducted as split plot factorial in randomized complete block design in 1998 at Hashemabad station, Gorgan. The main plots were two planting arrangements of cotton (60x27 and 80x20 cm) and subplots were factorial of seed rates and planting times of berseem clover. The planting arrangement of 60x27cm resulted in highest plant hieght, number of reproductive branches, number of boll per plant, and total yield of seed cotton. Technological properties of fiber of 60x27cm were better in comparison to 80x20cm. It seems that the planting arrangement of 60x27cm is an appropriate planting arrangement for cotton. Seed rate and planting time of berssem clover and interactions of experimental factors had no effect on cotton.

In the modern era, population growth has led to an increase in many related issues. One of these is the causes related to agriculture. In recent years, the use of planting techniques that can properly prepare the seedbed and sow the seeds at an almost uniform depth, has become more necessary than ever. SolidWorks software was used to design this car. Statistical data were analyzed using IBM SPSS software. Cultivation on raised bed is one of the most modern cultivation methods in the world. In this type of cultivation, without any tillage operations and directly, all cultivation stages are done in one stage. The device was built in six rows. In order to investigate six types of planters for growing chickpeas (representative of coarse-grained) and rapeseed (representative of fine-grained), an experiment was conducted using strip plots in a completely randomized block design with four replications in the 2021-2022 crop year. Soil moisture content, soil texture and soil temperature were extracted before planting. The parameters measured in this plan were: fracture percentage, planting depth, uniform distribution and seed fall and seed germination percentage. The machine was built with a working width of 1.5 meters, a length of 1.5 meters and a height of 2.3 meters. The construction of this car was done in the industrial complex of Barzegar Machine in Hamedan city. Type of planter in six levels b1: V-shaped, b2: U-shaped, b3: T- inverse, b4: Two-plate V-shaped, b5: cross-shaped and b6: Tulip-shaped were tested. The main purpose of this study is to build a device with a suitable planting arrangement for direct sowing machines in Iran (modeled on growers from other countries), to develop technical knowledge of the application of some planting methods, to eliminate the traditional methods of the past, Instantaneous monitoring of planting machine performance as well as increasing farmers' confidence in using planting machines to grow fine-grained crops. SolidWorks2021 software was used to design this machine. Statistical data were analyzed using IBM SPSS 25 software. The device was built in six rows. In order to evaluate six types of planters for growing chickpeas and rapeseed, an experiment was conducted using strip plots in a completely randomized block design with four replications in the crop year 1399-1400. The parameters measured in this plan were: fracture percentage, planting depth, uniform distribution and seed fall and seed germination percentage. The construction of this car was done in the industrial. Complex of Barzegar Machine in Hamadan. The type of planter was tested in six levels: b1: v-shaped, b2: u-shaped, b3: inverted t, b4: two-plate v-shaped, b5: cross-shaped and b6: tulip-shaped. The general purpose of this study is to build a device with suitable planting arrangement for direct sowing machines in Iran. The results showed that the crusader has a significant advantage over the other operators in the studied four parameters at the level of 5%.The general review of the research results showed that the crusader has a significant advantage over the other operators in the studied four parameters at the level of 5%. Compared to the other five types of crushers and in relation to the highest numbers obtained from the treatments, cross-planting increased the uniformity coefficient of planting depth by 7%, uniformity of seed longitudinal distances by 23% and germination percentage by 2.3% compared to other Has been planted. The percentage of seed breakage decreased by changing the distribution from cast iron to plastic oblique by 1.25%. These results show the superior design and distribution mechanism, planters and different settings of the machine in the cultivation of coarse and fine grain crops. Increasing the growth rate did not have a significant effect on the parameters of fracture percentage, uniformity coefficient of planting depth and coefficient of uniformity of seed longitudinal distances. However, it has significantly reduced the green percentage. The overall results showed that a cross-planter with a diagonal plastic distribution and a telescopic fall tube is more suitable for sowing coarse seeds. The mentioned planters are not suitable for small seeds. In general, with the results and relationships obtained from the research, it was possible to monitor planting operations and receive feedback on the improper operation of the machine in agricultural fields. The results and coefficients of explanation of the field test were weaker than the laboratory results. Compared to the other five types of crushers and in relation to the highest numbers obtained from the treatments, cross-sowing increases the uniformity coefficient of planting depth by 7%, uniformity of seed longitudinal distances by 23% and germination percentage by 2.3% compared to other planters.

Tobacco (Nicotiana tabacum L. ) is a significant cash crop in Iran. It serves as a source of income for smallholder farmers and commercial fields. In order to investigate the growth indices and yield of two Virginia tobacco cultivars an experiment was conducted in a split factorial based on RCBD design with eight treatments and three replicates during the 2020 cropping seasons. The treatments consisted of two application methods of N and K fertilizer (soil and foliar application), planting arrangement (double-and single-row) in the main plot and two Virginia tobacco cultivars (TC100 and NC100) in the sub-plot. Results showed that the highest value of tobacco leaf area index (LAI), crop growth rate (CGR), relative growth rate (RGR), and total dry matter (TDM) were recorded where TC100 cultivar planted in double-row spacing and sprayed with N and K nutrients. Conversely, the lowest values of LAI, CGR, RGR and TDM were recorded where the NTC100 cultivar was planted in single-row spacing and received soil application of N and K. The overall results indicated that double-row and foliar application of N and K fertilizers could improve tobacco growth indices and ultimately its yield.

In order to find essential information for efficiency management of field corn, a field experiment was conducted in 2001and 2002 at agricultural research center of Iranshahr. This research was laid out in a randomized complete block design arranged in a split plot with four replications for two years (2001-2002). Plant density (D1=70000, D2=80000, D3=90000 & D4=10000) were the main plot and planting patterns (p1=single row, p2=double row with 15cm space and p3=double row with 20cm space) were the subplots. Analyze variance of growth indices and dry matter trend accumulation was down on bias degree -days. Result showed in this study with increasing plant density up specific limit (90000 plant/ha) LAI, CGR and NAR increased. With double row, single row plant arrangement and in a many densities much and overlap shading because of leaf amount LAI, CGR, NAR decreased. With changing arrangement single row to double row due created cover more complete and produce farther LAI in rate light absorption, had one exist domination intercept this factor in necessary ground for will verticality maximization of CGR verticality As more space of content for each shrub and possibility access more light resources, water and nutrient special in season later have increased RGR. The biomes increased at all growth stage planting density of 100000 plants per hectare produced the highest biomes up the 1797 degree-days. There was not any difference between single and double row arrangement during early stage of growth but at later stage the difference was significant because canopyincrease and competition between the plants. Accumulation of grain dray matter was very fast at early growth stage but it happens slowly at later stage of growth since the photosynthetic source diminishes and translation material.