H. R. Sadeghnezhad; Maryam Barzanooni; Hossein Ali Shamsabadi; Mohammad Hashem Rahmati
Abstract
In no-tillage, the coulters are the best way to cross the plant residues, which, along with the furrow openers, prepare the soil for seed placement. So four available tiller models in front of a mechanical row crop planter were installed and a two factor randomized complete block design using strip plots ...
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In no-tillage, the coulters are the best way to cross the plant residues, which, along with the furrow openers, prepare the soil for seed placement. So four available tiller models in front of a mechanical row crop planter were installed and a two factor randomized complete block design using strip plots with four coulters (sweep, nail, narrow chisel and T inverted) as factor A and the three factors related to the speed of tractor (4.8, 7.2 and 9.4 km.h-1) as factor B were performed. The planter units were adjusted on 50 cm distance between rows. The sweep model with 24.4 and 7.3 cm had the highest width and depth of disturbed soil. T inverted tiller at the specified depth with the least amount of standard deviation got the highest uniformity of seed distribution on the row that was 80.4% and did not change depth of seeding by speed increasing but increased the distance between two seeds. Also, the highest quality of feed index (42.7%) and the lowest multiple index (46.8%) were related to this treatment and its miss index (10.5%) has been around other tillers. Although T inverted tiller in the forward speed of 4.8 km h-1 has better performance in terms of planting indices, but the nail tiller is more suitable because of simplicity and performance as well as its low cost compared to other tested tillers and it passes through plant residues more easily.
Mohammad Esmaeil Asadi; Hamidreza Sadeghnezhad
Abstract
Currently, the area of agricultural land under conservation practices in the world exceeds 180 million hectares, one of the main advantages of which is improvement in crop water productivity (CWP). An investigation in soybean cultivation in a farm with different level of management of residues ...
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Currently, the area of agricultural land under conservation practices in the world exceeds 180 million hectares, one of the main advantages of which is improvement in crop water productivity (CWP). An investigation in soybean cultivation in a farm with different level of management of residues was carried out in a randomized complete block design with split plot design in 2010 and 2011 at Gorgan Agriculture Research Station. Main treatment was residue management at three levels: R1: burning of residue , R2: retaining 50% of residues, and R3: maintaining 100% of residues; the secondry treatment was tillage practises at three levels: T1: conventional tillage (plowing + disk + row crop planter), T2: minimum tillage (stubble cultivator + row crop planter) and T3: no tillage (sowing with no till planter). The best results obtained from R2 and T3: 42.7% and 17.4% increase in yield respectively, comparing R1 and T1. The highest and lowest of water consumption level were found 3950 m3 ha-1 and 2690 m3 ha-1 in R1 and R3 respectively. The maximum and minimum CWP were found in R2 and R1 treatments with 1.13 kg m-3and 0.55 kg m-3 respectively. Sowing with no tillage system in irrigated conditions improved CWP by 15.3% compared to the conventional method.
