Tillage and residue management effect on soil hydro-physical environment under pigeonpea (Cajanus cajan)-wheat (Triticum aestivum) rotation

Abstract

A study was conducted in a long-term (6 year) experiment on tillage and residue management on a sandy loam soil
(Typic Haplustept) in pigeonpea [Cajanas cajan (L.) Millsp]-wheat (Triticum aestivum L.) cropping system at IARI
research farm, New Delhi for evaluation of the soil hydro-physical environment. Residue application significantly affected soil bulk density (Ï_b) and penetration resistance (PR), which were lowest in conventional tillage with residue incorporation (CTRI) (Ï_b =1.52 Mg/m³, PR=1.27 MPa). The PR was highest in no-till and bare (NT) (1.77 MPa), while residue retention in no tillage (NTRM) significantly reduced PR (1.65 MPa). A hard pan (PR between 1.72 - 1.80 MPa and Ï_b between 1.66-1.78 Mg/m³ ) was detected 0.1- 0.2 m layer. Mean weight diameter of 0-0.10 soil layer under NT and NTRM became 1.5 and 1.3 times that of its value of 0.396 mm and 0.435 mm, respectively, under CT. Soil macro-pores were 30-40% higher in NT and NTRM. Residue incorporation could improve transmission pores in conventional tillage, which might have contributed in better water retention in soils.