Influence of Tillage Practices on Soil Physical Properties and Growth and Yield of Maize in Jabal al Akhdar, Libya

Abstract

Different tillage practices are used for maize cropping in Libya. Yet, the effects of these practices on soil physical properties and maize growth and yield are not known. The objective of this study was to evaluate the effect of different tillage practices on soil physical properties and maize growth and yield in Libya. A field experiment was conducted in 2009 and repeated in 2010 using three tillage practices (conventional tillage (CT), ridge tillage (RT) and zero tillage (ZT)). Data about soil physical properties (penetration resistance (PR), bulk density (BD), total porosity (TP) and saturated hydraulic conductivity (Ks)) across soil depths, maize growth components (plant height, number of leaves, leaf area index and dry root weight) at 60, 75 and 125 days after planting, and maize yield (grain and stover) at harvest were collected and statistically analyzed in both years. To evaluate the effects of the tillage practices economically, the tillage operation cost and production cost were calculated. The results showed that at the surface layer (0 - 20 cm), CT had lower PR and lower BD, but higher TP and Ks compared to RT and ZT. At 20 - 40 cm and 40 - 60 cm depths, the lower PR and PD and higher TP and Ks were under ZT and RT compared to CT. All maize growth parameters at different times were highest for CT followed by RT and lowest for ZT. The CT practice presented the highest grain and stover yield followed by RT and ZT. However, harvest index was higher where ZT was applied. While tillage operation costs were the highest for CT followed by RT and ZT, the production costs were the highest for ZT followed by RT and CT. In general, the CT practice produced higher maize growth and yield, lower production cost, and higher tillage operation cost than those are planted using RT and ZT practices.