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Abstract: The effect of sole application of inorganic fertilizers (NPK) (N:P:K:: 30:26:25kgha−1) and combined application of farmyard manure (FYM) @ 4Mgha−1 and inorganic fertilizers (NPK+FYM) vis-a-vis non-application of fertilizers and manures (control) on changes in soil physical properties and plant growth characteristics of soybean (cv. JS 335) was studied in a deep Vertisol at the Indian Institute of Soil Science, Bhopal during the year 2001–2004. The results indicated that conjunctive use of recommended dose of fertilizer and farmyard manure (NPK+FYM) resulted in significant (P <0.05) decrease of bulk density (9.3%), soil penetration resistance (42.6%) and increase in hydraulic conductivity (95.8%) and mean weight diameter of the water stable aggregates (13.8%) and soil organic carbon content (45.2%) compared to control. Among the aggregates, in macro-aggregate fraction (250–500μm and 500–1000μm size fraction) and in large macro-aggregate fraction (>2000μm) maximum soil organic carbon concentration was recorded under NPK+FYM. The root mass of soybean was mostly (98%) confined to 15cm soil depth. Combined application of NPK and FYM recorded significantly higher (P <0.05) root length density and root mass density of soybean in the 0–15cm soil layer at flowering stage over NPK (28 and 65%) and control (63 and 175%). The root length density of soybean was significantly negatively correlated with the penetration resistance (r =0.98, P <0.05). Application of FYM @ 4Mgha−1 with NPK significantly (P <0.05) improved the biomass partitioning towards pod over NPK and control. The grain yield, water use efficiency and nitrogen use efficiency of soybean under NPK+FYM were significantly (P <0.05) higher than NPK and control. The total above ground biomass and the leaf area index at R8 stage could account for respectively, 89 and 63% variation in grain yield of soybean. Therefore in every crop season, integrated use of farmyard manure at 4Mgha−1 and recommended dose of chemical fertilizers may be practised in Vertisols for improving soil physical environment and achieving higher soybean productivity through efficient utilization of water and nutrients. [Copyright &y& Elsevier]

The Indo-Gangetic Plains (IGP) of India is dominated with rice − wheat cropping system that occupies almost 10.5 million ha area. The sustainability of rice-wheat system is under threat due to numerous water-, nutrients-, weeds- and environment-related problems, mainly, due to the cultivation of rice. Suitable crop and soil management practices with a bias to conservation agriculture (CA) that can sustain soil and environmental health as well as improve crop and water productivity, are required for the Indian IGP. Maize can be a viable alternative to rice and a potential driver for diversification of rice-wheat system. The acreage of maize is on the increase in conventional and conservation agriculture-based cereal systems of India in recent years. Therefore, a field experiment, involving a maize ( Zea mays L.)-wheat cropping system was undertaken on a sandy clay loam soil for three years (2010–11 to 2012-13) in New Delhi to evaluate the impacts of CA on crop and water productivity, profitability and soil organic carbon (SOC) accumulation. There were five CA-based treatments in first year, and two treatments were introduced in second year (2011-12) onwards. The experiment was laid out in a randomized complete block design with three replications. In all the residue retention plots, wheat residue was retained in maize crop and maize residue was retained in wheat crop under zero till conditions. Results showed that the plots under permanent broad bed with residue (PBB + R) and without residue (PBB) resulted in ∼29 and ∼26% higher maize grain yield, respectively than conventional tillage (CT) (2.6 t ha −1 ), but wheat grain yields were comparable in all the treatments in first year. Maize grain yield in second year under PBB + R and zero tillage with residue (ZT + R) were 55 and 43% higher than CT plots (2.8 t ha −1 ). Three-year mean maize yields due to PBB + R and permanent narrow bed with residue (PNB + R) were 28 and 15% higher than that in CT plots (3.3 t ha −1 ). The PBB + R resulted in 11% higher two-year mean water productivity in maize than PBB (∼without residue), but both these treatments were comparable in this regard in wheat. The ZT + R plots resulted in 14% and 22% higher two-year mean water productivity, respectively in maize and wheat than ZT plots. Overall, the plots under PBB + R had 57% and 19% higher mean water productivities in maize and wheat, respectively compared with CT plots. Again, the PBB + R plots gave 12% higher two-year mean net returns compared with CT plots. With regard to net returns, the plots under permanent narrow bed with and without residue (PNB + R; PNB) were inferior to PBB, PBB + R, ZT and ZT + R plots. Retention of both-season crop residues could significantly improve SOC concentration in surface (0–5 cm) soil. The PBB + R resulted in highest SOC pool at 0–30 cm soil layer, which was significantly higher than that in CT. This system showed maximum carbon sequestration potential. Thus, this CA practice, which involves PBB + R is superior to other practice. This would save water through higher water-use efficiency, and lead to accumulation of more carbon in soil with higher sequestration potential, besides giving sustainable production through maize-wheat system over the years. This can be adopted across the IGP regions of India, where irrigated rice-wheat system is in practice, and in similar agro-ecologies of the tropics and sub-tropics under irrigated conditions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Optimization of date of sowing and cultivars of Indian mustard was done for enhancing productivity. [•] We attempted to compute radiation and water use efficiency of Indian mustard under varied crop growth environments. [•] We developed evapo-transpiration production function and radiation production function for Indian mustard. [Copyright &y& Elsevier]