Globally, many developing countries are facing silent epidemics of nutritional deficiencies in human beings and animals. The lack of diversity in diet, i.e., cereal-based crops deficient in mineral nutrients is an additional threat to nutritional quality. The present review accounts for the significance of biofortification as a process to enhance the productivity of crops and also an agricultural solution to address the issues of nutritional security. In this endeavor, different innovative and specific biofortification approaches have been discussed for nutrient enrichment of field crops including cereals, pulses, oilseeds and fodder crops. The agronomic approach increases the micronutrient density in crops with soil and foliar application of fertilizers including amendments. The biofortification through conventional breeding approach includes the selection of efficient genotypes, practicing crossing of plants with desirable nutritional traits without sacrificing agricultural and economic productivity. However, the transgenic/biotechnological approach involves the synthesis of transgenes for micronutrient re-translocation between tissues to enhance their bioavailability. Soil microorganisms enhance nutrient content in the rhizosphere through diverse mechanisms such as synthesis, mobilization, transformations and siderophore production which accumulate more minerals in plants. Different sources of micronutrients viz. mineral solutions, chelates and nanoparticles play a pivotal role in the process of biofortification as it regulates the absorption rates and mechanisms in plants. Apart from the quality parameters, biofortification also improved the crop yield to alleviate hidden hunger thus proving to be a sustainable and cost-effective approach. Thus, this review article conveys a message for researchers about the adequate potential of biofortification to increase crop productivity and nourish the crop with additional nutrient content to provide food security and nutritional quality to humans and livestock.

Combined application of manures and fertilizers played a pivotal role in the improvement in soil physico-chemical properties, macro and micronutrients distribution and their transformations under different cropping systems. Based on a cropping system, the different levels of manures and fertilizers were used to study improvement in physico-chemical properties of soil. The aim was to explore the appropriate application of organic manures and inorganic fertilizers for improved sustainable yields of a cropping system. Intensive cropping systems lead to N, P, K, Zn, Cu, Fe, and Mn deficiencies in surface and subsurface soil, which could be refreshed with combined application of manures and fertilizers. The application of manures and fertilizers controls the pH and electrical conductivity of soil. Moreover, manures and fertilizers showed improvement is soil physical conditions viz. bulk density, particle density, porosity, and water holding capacity etc. Manuring coupled with fertilization helped to great extent for macro and micronutrient transformations in the soil. Under these transformations, the soil solution and water soluble component (fractions/pools) of soil is enriched with macro and micronutrients. There was a consistent declining trend of DTPA-extractable Zn, Cu, Fe, and Mn in the sub-surface soil in comparison to the surface layer, which may be ascribed to increase in pH with increase in depth and decrease of organic matter with depth. Similarly, manures reduced the concentration of residual macro and micronutrients in soil. Recently, integrated nutrient management system (INMS) is gaining importance vis-a-vis maintaining the soil fertility with conjunctive use of chemical fertilizers plus organic manures.

Toward an attempt to limit the global warming to 2 °C, there has been an increasing emphasis on devising suitable policies and practices for entrapment and storage of atmospheric CO₂ to mitigate the detrimental effects of climatic change. Agriculture being a predominant global land use, C sequestration under different agro-ecosystems through appropriate management practices is an important option to combat the anthropogenic climate change. Conservation tillage along with residue management, stubble retention, mulching, organic farming and integrated nutrient management not only facilitates soil C storage but also improves soil health. Change in land-uses and cropping system also impart notable effects on soil C turnover. Biochar application is found effective in augmenting soil C stock and improving soil aggregation. Bioenergy plantations are also effective in sequestering C. Simulation models and remote sensing are innovative tools for predicting and mapping soil C status and identifying site-specific strategic policies to minimize the risk of land degradation and to maintain environmental sustainability. Therefore, the aim of this review is to disseminate ideas regarding current C status, identify researchable priorities and to deliberate pros and cons of agricultural management practices for better implementation of soil C sequestration strategies for mitigating the consequences of climate change. Graphical abstract

A field investigation on direct seeded rice (DSR) was carried out in the two consecutive rice growing seasons of 2017 and 2018 at Pantnagar, Uttarakhand, India for the development and validation of soil test crop response (STCR) to fertilizer and for assessing the performance of STCR-treatments as compared to the general recommended dose (GRD) in terms of yield, nutrient uptake and use efficiency, and the economics of DSR. For producing 1 Mg of rice-grain, the required nutrients (N, P, and K) were 2.01 kg, 0.44 kg, and 3.06 kg; the contribution from the soil was 22.05%, 37.34%, and 41.48%; from applied farmyard manure 23.25%, 28.34%, and 16.80%, from fertilizer 38.08%, 49.93%, and 252.98%; and from fertilizer with FYM 44.83%, 60.57%, and 278.70%; for N, P, and K, respectively. The STCR approach, with or without FYM, at both the target yields (4.5 Mg ha⁻¹ and 5.0 Mg ha⁻¹) markedly enhanced the grain yield (20.2% to 32.3%) and production efficiency over the GRD. It also exhibited a higher NPK uptake and use efficiency, along with better profitability, than the GRD. Therefore, the STCR-targeted yield approach could improve the yield, economics, and efficiency of nutrient use for direct seeded rice.