Organic, integrated and chemical farming in wheat (Triticum aestivum) under maize (Zea mays)–wheat cropping system

A field experiment with organic vs chemical farming with maize (Zea mays L.)–wheat (Triticum aestivum L. emend. Fiori & Paol.) system was initiated during 1996–97. On the same field, the investigation was expanded to organic (pure), integrated (partial) and chemical farming systems during winter seasons of 2001–02 and 2002– 03 and was conducted at the experimental farm, Ludhiana, on sandy-loam irrigated soil. In maize–wheat sequence, on an average M₂₀-M₂₀-RI [FYM 20 tonnes/ha each to maize and wheat and incorporation of residues (RI)], M₁₀-M₁₅-GM, RI (GM-green manuring before maize), Rec.-GM-RI (Rec.-recommended chemical fertilizers) and Rec.-GM-R0 (R0-residue removed); pure and partial organic farming treatments gave 12.4, 8.3, 8.0 and 5.9% higher wheat grain yield than the Rec. treatment. M₂₀-M₂₀-RI and M₁₀-M₁₅-GM-RI (pure organic), Rec.-GM-RI and Rec.-GM-R0 (partial organic) treatments produced significantly higher plant height, dry-matter accumulation, leaf-area index, PARI (%), effective tillers/m², ear length, number of grains/ear and recorded higher root density and SPAD readings and also showed less canopy and soil temperature as compared to Rec. treatments.