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This study evaluated energy requirements and input-output energy relationship in a maize-wheat-greengram cropping system under conventional and conservation agriculture. Conventional tillage with flat bed (CTF) and raised bed (CTB) and zero tillage with flat bed (ZTF) and raised bed (ZTB) were supplemented with crop residue management viz., no residue (CON), wheat residue in maize crop (WR), maize residue in wheat crop (MR) and wheat + maize residue in both maize & wheat crops (WMR). Results showed that ZTB (89170 MJ/ha) consumed 8% lower input energy than CTF. ZTB saved 91% and 38% energy in land preparation and irrigation, respectively. The output and net energy return were significantly higher with ZTF (387235 MJ/ha; 295397 MJ/ha), which were 2.0% higher than ZTB. Energy ratio and productivity were significantly higher with ZTB. WMR contributed the highest input and output energy and lowered energy ratio and productivity. Reduced energy ratio and energy productivity can be ignored as it returned to soil to improve its quality. Surface retained residues had better effect on crop productivity. With this view, ZTB with WMR was better and would be a substitute of the conventional agricultural system for adoption in maize-wheat-greengram cropping system in the irrigated north western Indo-Gangetic Plains. [ABSTRACT FROM AUTHOR]

• Unified SQI was developed after 8 years of CA through PCA using 15 soil parameters. • The ZTDSR – ZTM – ZTSMB (+R) system had highest, whereas TPR-CTM had lowest SQI. • The ZTDSR – ZTM – ZTSMB (+R) resulted in ∼14 % higher total SOC than the TPR – CTM. • The key indicators were hydraulic conductivity, pH, total N, available P and K. • CA practice maintained higher soil quality and crop yield in rice-mustard system. The systematic research on the effect of medium-term conservation agriculture (CA) on soil quality, especially under the rice (Oryza sativa L.)-based cropping systems is limited. Hence, the specific objective of the study was to develop soil quality indices with key soil physical, chemical and biological indicators under the conservation and conventional tillage practices in a rice–mustard [ Brassica juncea (L.) Czern.] cropping system. Eight treatment combinations including tillage and crop establishment, crop residue and cropping system intensification with inclusion of short duration summer mungbean [ Vigna radiata (L.) Wilczek] were adopted in rice - mustard cropping system in hot semi-arid, sub-tropical north-western Indo-Gangetic Plains agro-ecoregion of India. Soil samples collected from topsoil (0−5 cm) and 5−15 cm soil layer were analyzed for 15 physical, chemical and biological properties to develop unified soil quality index (SQI) through principal component analysis (PCA). The highest SQI was obtained in the zero till direct seeded rice (ZTDSR) – zero till mustard (ZTM) –ZT summer mungbean (ZTSMB (+R) (mungbean residue in ZTDSR - rice residue in ZTM- mustard residue in ZTSMB) treatment followed by the ZTDSR + BM (brown manuring) – ZTM (+R) (mustard residue in ZTDSR with BM – rice residue in ZTM). The lowest SQI was obtained in transplanted puddled rice (TPR) - conventional till mustard (CTM) for both soil layers. The identified key indicators for SQI in this Inceptisol were saturated hydraulic conductivity (K s), pH, total N, available P, and available K. Besides, the plots under ZTDSR – ZTM – ZTSMB (+R) resulted in 14 % higher total organic C in topsoil and 28 % higher aggregate stability than the TPR - CTM plots. This ZTDSR – ZTM -ZTSMB (+R) treatment had 65 % higher surface soil microbial biomass C than the TPR – CTM treatment. The ZTDSR – ZTM -ZTSMB (+R) treatment also led to higher K s , which was in the order of triple ZT > double ZT > ZT > conventional tillage. Thus, the medium-term CA with triple or double zero tillage with crop residue retention could lead to maintain agricultural sustainability under rice-mustard system. Hence, it may be recommended to the farmers for adoption. [ABSTRACT FROM AUTHOR]