Climate prediction models suggest that agricultural productivity will be significantly affected in the future. The expected rise in average global temperature due to the higher release of greenhouse gases (GHGs) into the atmosphere and increased depletion of water resources with enhanced climate variability will be a serious threat to world food security. Moreover, there is an increase in the frequency and severity of long-lasting drought events over 1/3rd of the global landmass and five times increase in water demand deficits during the 21st century. The top three cereals, wheat (Triticum aestivum), maize (Zea mays), and rice (Oryza sativa), are the major and staple food crops of most people across the world. To meet the food demand of the ever-increasing population, which is expected to increase by over 9 billion by 2050, there is a dire need to increase cereal production by approximately 70%. However, we have observed a dramatic decrease in area of fertile and arable land to grow these crops. This trend is likely to increase in the future. Therefore, this review article provides an extensive review on recent and future projected area and production, the growth requirements and greenhouse gas emissions and global warming potential of the top three cereal crops, the effects of climate change on their yields, and the morphological, physiological, biochemical, and hormonal responses of plants to drought. We also discuss the potential strategies to tackle the effects of climate change and increase yields. These strategies include integrated conventional and modern molecular techniques and genomic approach, the implementation of agronomic best management (ABM) practices, and growing climate resilient cereal crops, such as millets. Millets are less resource-intensive crops and release a lower amount of greenhouse gases compared to other cereals. Therefore, millets can be the potential next-generation crops for research to explore the climate-resilient traits and use the information for the improvement of major cereals.

Dwindling supplies of fossil fuels and their deleterious impacts on human health and the global environment have intensified the search for substitute energy sources. Biodiesel has been identified as a promising renewable energy substitute for diesel fuel due to several comparable and sustainable properties. However, approximately 95% of biodiesel is derived from edible oil crops, threatening the current food supplies. Therefore, the biodiesel production potential from inexpensive, non-edible, and non-conventional bioenergy crops, such as Jatropha (Jatropha curcas L.), has attracted the attention of many researchers, policymakers, and industries globally. Jatropha is considered to be the second-generation biofuel feedstocks for biodiesel production. However, sustainable biodiesel generation from J. curcas oil has not yet been attained, owing to different socio-economic, ecological, and technical factors. This study aimed to synthesize the information from the existing literature on the present status and to identify the knowledge gaps for future research on Jatropha by providing comprehensive information regarding its origin and distribution, morphology, phenology, and reproduction, genetic diversity, its productivity, oil content, and fatty acid composition, the methodology used for extracting biodiesel, and agronomic, economic, and environmental aspects of biodiesel production. The germplasm screening of J. curcas and the exploration of its adaptability and agronomic potential across diverse climates are highly desired to promote this crop as an alternative biofuel crop, particularly in arid and semi-arid regions. Moreover, future research should focus on developing, optimizing, and modernizing the technologies involving seed collection, the processing of seeds, oil extraction, and the production of biodiesel.

Carinata (Brassica carinata A. Braun), a non‐food oilseed and an alternative biofuel feedstock, has received attention for its potential as a low‐input option for production in the semi‐arid regions of the Northern Great Plains (NGP). This study was conducted to (a) determine the economic optimum N and S fertilization rates and (b) determine the interactive effects of N and S fertilization on seed yield and agronomic traits in carinata. The field experiment conducted in 2017 and 2018 at Brookings, SD, had four N rates (56, 84, 112, and 140 kg N ha⁻¹) and three S rates (0, 22, and 45 kg S ha⁻¹). Increasing N rate increased seed and oil yield each peaking at 112 kg N ha⁻¹ in both years. Applying S fertilizer increased seed and oil yield and oil concentration over the control but with the two S rates performing similar in both years. In the absence of S application, seed yield was reduced irrespective of N rate indicating that S is critical to obtain a positive response to N fertilizer. Economically optimal N rate ranged from 47 to 93 kg N ha⁻¹ whereas economic optimum S rate ranged from 20 to 26 kg S ha⁻¹. The economic optimum yield ranged from 1.0 Mg ha⁻¹ to 1.5 Mg ha⁻¹. These findings suggest that carinata seed yield and agronomic trait response to N fertilization can vary depending on S availability in the soil.

Carinata (Brassica carinataA. Braun), a non‐food oilseed crop and an alternative bio‐jet fuel feedstock, has received attention for its potential as a low‐input option for production in the semi‐arid region of the Northern Great Plains of the United States. Research addressing the impacts of nitrogen (N) and sulfur (S) fertilizers on soils and greenhouse gas (GHG; CO₂, N₂O, and CH₄) emissions from carinata production are limited. Thus, objective of this study was to evaluate the impact of different rates of N and S fertilizers applied to carinata on soil properties and GHG emissions. Field experiments were conducted in 2017 and 2018 to assess the response of carinata to four N (56, 84, 112, and 140 kg N ha⁻¹) and three S (0, 22, and 45 kg S ha⁻¹) rates. Soil samples were collected at crop harvest to measure soil properties; however, soil surface GHG fluxes were measured during 2017 and 2018 growing seasons using static chamber method. Data showed that application of N fertilizer increased soil EC, soil organic carbon (SOC), stable C, and labile N. However, sulfur fertilizer decreased SOC, labile N, and soil inorganic N contents. Results from GHG fluxes showed that higher rates of N fertilizer application increased the soil CO₂and N₂O emissions, whereas the S fertilizer did not impact these fluxes. This study concludes that S and N fertilizers application to carinata crop affected soil properties, and higher rates of N fertilizer increased the GHG emissions. Therefore, N fertilizer application rate needs to be optimized to mitigate GHG emission for carinata production.

Large-scale burning of rice straw causes air pollution and deterioration of soil health, which challenges the sustainability of the rice–wheat system (RWS) in north-western India. In a field experiment on sandy loam (Typic Ustochrept) soil at Punjab Agricultural University, India, with split plot design, effects of four nitrogen (N) levels (0, 90, 120, and 150 kg N ha⁻¹) in main plots and four levels of rice straw (RS) incorporation (0, 5, 7.5, and 10 Mg ha⁻¹) in wheat in sub-plots were studied after 7 years on carbon (C) pools at maximum tillering (MT) and flowering (FL) stages of wheat and crop yields. Rice straw (RS) incorporation at 10 Mg ha⁻¹ with N application at 120 kg N ha⁻¹ in wheat not only increased labile C pools significantly especially at MT but also increased the wheat yield compared with no straw incorporation. Principal component analysis suggests that total polysaccharide carbon, basal soil respiration, and pH can be used as sensitive parameters for assessing soil quality in RWS.

The slowly establishing salt‐tolerant perennial grasses reduced nitrous oxide (N₂O‐N) emissions from saline/sodic soil compared to barren areas. Other salt‐tolerant species may accelerate vegetative establishment and reduce N₂O‐N emissions. In a greenhouse study, barley (Hordeum vulgare L.), Florida broadleaf mustard (Brassica juncea L.), and Kernza intermediate wheatgrass [Thinopyrum intermedium (Host) Barkworth & D. R. Dewey] were grown for 63 days to compare shoot biomass and chemical composition, N₂O‐N emissions, and the soil microbiome between saline/sodic and productive (non‐salt impacted) soils. Emissions were measured six times daily from 1 to 22 and 42 to 63 days after planting (DAP). Shoot and soil microbial biomass and communities were quantified 63 DAP. N₂O‐N emissions were 87% greater from no‐plant saline/sodic than no‐plant productive soil (p < 0.05). N₂O‐N emissions were reduced from planted treatments soon after plant emergence. N₂O‐N emissions reductions from saline/sodic soil during the first 22 DAP were 84%, 76%, and 61% for barley, mustard, and Kernza, respectively. Barley had the greatest shoot biomass and impact on the soil microbial community, increasing the fungi to bacteria ratio from 0.063 to 0.094 in the productive soil and from 0.056 to 0.076 in the saline/sodic soil. Plant‐induced changes to the soil microbiome, and decreased soil inorganic N and water, contributed to N₂O‐N emission reductions. Archived field samples from grass‐established saline/sodic soil areas had a fourfold increase in nos‐Z gene copy number compared to no‐plant controls, which may, in part, explain decreased N₂O‐N emissions. Establishing these vigorous species may aid in restoring multiple ecosystem services to saline/sodic areas.