Naeim Loveimi; Elyas Dehghan
Abstract
In some parts of Iran, wheat will be grown up upon harvesting of previous crop, rice. Leaving over paddy stems, as plant residues, could be a good solution due to limitation of time between harvesting of rice and preparing the land for sowing wheat. On the other hand, the presence of rice ...
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In some parts of Iran, wheat will be grown up upon harvesting of previous crop, rice. Leaving over paddy stems, as plant residues, could be a good solution due to limitation of time between harvesting of rice and preparing the land for sowing wheat. On the other hand, the presence of rice residues can affect the performance of the direct planter and consequently on the yield of wheat. This study was conducted in Khuzestan province, Iran, for two years (2015-2017) to investigate the effects of height of standing rice residues, stubble height, on grain yield of wheat when direct planting machine, Gaspardo machine, was used to sow the seeds. The experiment of this project was based on split plot with randomized complete blocks design with two factors and three replications. The main factor was the rice stubble height at three levels: 25, 35 and 45 cm, and the sub factors were the wheat seed rates at three levels: 160, 180 and 200 kg.ha-1.Analysis of variance in two years showed that stubble height and seed rates had significant effects on grain yield but interaction of them had no significant effect in this index. In addition to grain yield, stubble height caused significant effects on biological yield, seedlings per m2of land, and the number of grains per spike. Based on average of two years grain yield, it has been found that among stubble height, 25 cm with 4634 kg.ha-1and 45 cm with 3894 kg.ha-1had the highest and lowest value, respectively. From the point of biological yield, the highest (10524 kg.ha-1) and lowest (8894 kg.ha-1) value were found when the height of stubbles were 25 cm and 45 cm, respectively.
Elyas Dehghan; Seyed Mohammad Javad Afzali
Abstract
In dry clay soils, farmers irrigate the farm before tillage (pre-planting irrigation or PI) to reduce the soil resistance then tilling when the soil moisture sufficiently reduced for machine traffic. In this experiment, Five tillage-planting methods included direct drilling or seeding without PI (T1), ...
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In dry clay soils, farmers irrigate the farm before tillage (pre-planting irrigation or PI) to reduce the soil resistance then tilling when the soil moisture sufficiently reduced for machine traffic. In this experiment, Five tillage-planting methods included direct drilling or seeding without PI (T1), tilling with disk harrow (one pass) before direct seeding without PI (T2), direct seeding at field capacity condition of soil after PI (T3), direct seeding at high soil moisture condition after PI (T4), tilling with disk harrow (two passes), leveling, and seeding with traditional seeder(control T5) were compared in a randomized complete block design with three replications in terms of fuel consumption, operation time, plant number per square meter, number of weeds and grain yield of wheat. Results showed that T5and T4 with a grain yield of 5287 and 5168 kg/ha, were superior to other treatments. The highest number of weeds obtained in T3 with 42.34 m-2, while in T5, most of the weed controlled by disposing of the disk and decreased to 7.33 m-2. Finally, in the presence of enough water and time for PI T4 was better than T5 and recommended due to the lack of first irrigation and germination of wheat seeds with moisture in the soil, reduced fuel consumption from 34.11 to 11.35 lit/ha and reduce time required for tillage-planting operation from 2.91 to 0.40 h/ha compared to the control. Otherwise, T2 with grain yield of 4734 kg/ha is recommended, due to 30% reduction in fuel consumption and a reduction of 57% in time required than the control.
Elyas Dehghan; Mohammad - javad Sheikhdavoodi; Hassan Zaki-Dizaji; Abdolali Gilani
Abstract
High water consumption and the cost of labor in rice transplanting method is the reason for growing tendency of farmers to Dry-bed seeding of rice in Iran. High consumption of seed and inadequate specialized machines are the problems in rice dry-bed seeding. At present rice dry-bed seeding is done with ...
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High water consumption and the cost of labor in rice transplanting method is the reason for growing tendency of farmers to Dry-bed seeding of rice in Iran. High consumption of seed and inadequate specialized machines are the problems in rice dry-bed seeding. At present rice dry-bed seeding is done with traditional drill seeder with more than of 90 kg/ha seed consumption. While planting one seed in hole with a 20×20cm planting pattern in dry-bed seeding can reduce seed consumption to 5 kg/ha. This research was conducted for fabrication and laboratory evaluation a special seed plate for rice dry-bed direct seeding with pneumatic planter. Design parameters of Seed plate were included six plate shapes and three seed hole diameters. Seed plate shapes included traditional plate without groove and five groove shapes on plate, including three trapezoidal grooves with wall angle of 30, 45 and 60 degrees and two semicircle grooves with the aperture opening 2 and 3mm and three seed hole diameters 1.2, 1.3 and 1.5mm at the three levels of vacuum pressure 40, 50 and 60 milibar compared in a completely randomized design in a factorial experiment with three replications. Indices were, seed number per hole, miss index, over index and precision of feeding index. The results showed that creating the groove on the seed plate resulted higher seed cell covering and reduced miss and over index. New grooved plates had higher precision of feeding and lower miss index than conventional seed plate. By increasing the vacuum pressure and the diameter of the seed hole, miss index decreased and over index and seed number per hole increased. By increasing the angle of the walls of the trapezoid grooves and aperture of the semicircle grooves miss index reduced and over index and seed number per hole increased. In general, the results of laboratory evaluation Showed that for direct seeding of rice in dry-bed condition with pneumatic planter, using the seed plate with trapezoidal groove wall angle of 45 degrees and a diameter of hole 1.2 mm and vacuum pressure 50 mbar were better than others.
