Minimum tillage and increased residue retention improves soil physical conditions and wheat root growth in a rice-based cropping system

Wheat (Triticum aestivum L.) is grown in rice-based cropping systems of the eastern Indo-Gangetic Plain in soils subjected to repeated tillage to prepare puddled soil for preceding monsoon rice (Oryza sativa L.). Such soils commonly have a hard plough-pan layer (10-15 cm depth) which limits root growth and yield of wheat (Mohanty et al., 2006). Conservation agriculture offers the potential for improved soil physical properties and increased root growth and yield of wheat (Aggarwal et al., 2006). However, it is unclear whether such changes will occur in intensive rice-based cropping sequences and the dependence of improvement on crop residue retention. A field experiment assessed changes in soil physical properties after 7 consecutive crops in relation to minimum tillage and crop residue retention levels