Analysis and Meta-Analysis of Long-Term Effect of Tillage on Yield and Water Use of Wheat and Sorghum.

Abstract

To till or not too (no-till) is among the most important management decisions dryland crop producers have to make every cropping season. The objective of the study was to evaluate long-term effects of tillage on wheat and sorghum grain yield, available soil water, and water productivity. A 25-year study was conducted at Tribune, KS with conventional, reduced, and no-tillage treatments in a wheat-sorghum-fallow rotation. Data from published scientific research conducted on the effects of tillage were also collected and a meta-analysis was performed. Preliminary results of both the analysis and meta-analysis indicate that the effects of tillage on yield significantly varied by environment and crop. However, more consistently;

1. Sorghum yields benefited more from no-till compared to wheat
2. No-till yields were often superior or similar to conventional till
3. Soil water at planting were slightly lower for conventional than no-till
4. Water use was greater for no-till than conventional till
5. Water productivity was often similar between no-till and conventional till

Key environmental factors that showed significant interaction with tillage managements and determined yield of sorghum and wheat will be discussed.