Effect of Some Tillage Operations on Physical Properties of the Soil and Tractor Performance and Sorghum Crop Yield in Sondos Scheme.

Abstract

This study was conducted at the Demonstration Farm of the Faculty of Agricultural Technology and Fish Science, ALNeelain University, Sondos Agricultural Project, Jebel Awlia, about 50 km south Khartoum in the two successive seasons 2013/2014 and 2014/2015. The site lies in the semi-arid zone of the Sudan. The objectives is to investigate the effect of different six tillage operations, namely, zero tillage, d isc plough, chisel plough, disc harrow, disc plough + disc harrow and double ridging on soil physical properties, yield of sorghum crop as indicter plant and tractor parameters performance. The physical properties were bulk density, soil field capacity, infiltration rate and the yield sorghum crop and tractor parameters, parameters studied were plant height, number of tillers; leaves per plant, stem diameter and yield, the tractor performance parameters tested were fuel consumption, implement field capacity and efficiency, rear wheel slippage and draft. Finally economical analyses for cost of these different treatments were also studied. The experiment design adopted was completely randomized block design with four replicates. Results showed that bulk density values increased with increasing in depth. The plough + harrow treatment gave the lowest bulk density (1.23, 1.25g/cm³) where as zero tillage treatment gave the highest soil bulk density (1.35, 1.37g/cm³). Soil field capacity value decrease with increase in depth. Infiltration rate showed very high initial infiltration rate during the five minuets elapse time for all tillage treatments. Chiseling tillage operation registered the highest initial infiltration rate (288, 300mm/h) whereas zero tillage treatment gave the lowest (168, 180 mm/h) throughout the experiments. For the effect of different tillage treatments on sorghum yield component parameters, statistical analysis for plant height during the two seasons showed that chisel treatment gave a higher significant results (p ≤ 0.05) at all reading during the growing season compared to the other treatments, except with harrow, double ridging and disc plough+ harrow in the 2nd and 4th weeks. Zero tillage treatment registered the lowest plant height means (65.03, 72.75 cm) throughout the studied period. As for the number of tillers/ plant, statistical analysis at different reading during the growing season showed no significant difference (p ≤ 0.05) existed between treatments means. Number of leaves / plant also showed that there was no significant difference (p ≤ 0.05) between treatments studied except in the 6th week in season 1. As for stem thickness, results for season 1 showed that there was no significant difference (p ≤ 0.05) observed among tillage treatment means in the 4th, 6th and 8th weeks, but a significant differences existed between treatment means in the 2nd and 10th weeks in the second season, the statistical analysis showed that there were significant difference at (p ≤ 0.05) between disc plough, disc plough + harrow and harrow. Sorghum yield results showed that significant differences (p ≤ 0.05) found between different treatments means, disc plough + harrow treatment gave a higher value (0.92 - 1.01 ton/ha) followed by chisel plough (0.79 - 0.91 ton/ha) then disc plough (0.76, 0.82 ton/ha) and harrow (0.70, 0.77 ton/ha) treatments, whereas, double ridging and zero tillage gave the lowest sorghum yield throughout the two seasons (0.67, 0.76 ton/ha) (0.61, 0.57 ton/ha) respectively. The results show that implements effective field capacity and field efficiency decreased with increase in depth and also decrease with increase in moisture content in the soil for all operations. Also result showed that fuel consumption and slippage (%) increases with increase in depth and also increase with increase in moisture content for the implements tested. Draft and power requirement results for different treatments showed that, draft required by all the implements increased with increasing in the depth of tillage operation and soil moisture contents. For power requirement, maximum total power consumed by chisel plough at 30 cm depth at moisture content 40% (18.20 kw). Economical analysis for different tillage treatments in the two seasons showed that disc plough + harrow treatment gave higher return over zero tillage (44.34, 91.61$) followed by chisel (26.51, 84.69$), disc harrow (14.34, 54.34$) and double ridging treatments which gave the lowest profit( 2.47, 49.74$) result over zero tillage on the two seasons.