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Agricultural field experiments are costly and time-consuming, and often struggling to capture spatial and temporal variability. Mechanistic crop growth models offer a solution to understand intricate crop-soil-weather system, aiding farm-level management decisions throughout the growing season. The objective of this study was to calibrate and the Crop Environment Resource Synthesis CERES-Maize (DSSAT v 4.8) model to simulate crop growth, yield, and nitrogen dynamics in a long-term conservation agriculture (CA) based maize system. The model was also used to investigate the relationship between, temperature, nitrate and ammoniacal concentration in soil, and nitrogen uptake by the crop. Additionally, the study explored the impact of contrasting tillage practices and fertilizer nitrogen management options on maize yields. Using field data from 2019 and 2020, the DSSAT-CERES-Maize model was calibrated for plant growth stages, leaf area index-LAI, biomass, and yield. Data from 2021 were used to evaluate the model's performance. The treatments consisted of four nitrogen management options, viz., N0 (without nitrogen), N150 (150 kg N/ha through urea), GS (Green seeker-based urea application) and USG (urea super granules @150kg N/ha) in two contrasting tillage systems, i.e., CA-based zero tillage-ZT and conventional tillage-CT. The model accurately simulated maize cultivar's anthesis and physiological maturity, with observed value falling within 5% of the model's predictions range. LAI predictions by the model aligned well with measured values (RMSE 0.57 and nRMSE 10.33%), with a 14.6% prediction error at 60 days. The simulated grain yields generally matched with measured values (with prediction error ranging from 0 to 3%), except for plots without nitrogen application, where the model overestimated yields by 9-16%. The study also demonstrated the model's ability to accurately capture soil nitrate-N levels (RMSE 12.63 kg/ha and nRMSE 12.84%). The study concludes that the DSSAT-CERES-Maize model accurately assessed the impacts of tillage and nitrogen management practices on maize crop's growth, yield, and soil nitrogen dynamics. By providing reliable simulations during the growing season, this modelling approach can facilitate better planning and more efficient resource management. Future research should focus on expanding the model's capabilities and improving its predictions further., (© 2024. The Author(s).)

Indo-Gangetic plains (IGP) of South Asia have supported bulk of human and bovine population in the region since ages, and a spectacular progress has been made in food production. However, malnutrition, diminishing total factor productivity, and natural resource degradation continue to plague this cereal-dominated region, which is also vulnerable to climate change. Addressing these challenges would require a transition towards diversifying cereal rotations with agroecological cropping systems. A study was, therefore, conducted at the experimental farm of ICAR-CSSRI, Karnal on crop diversification and sustainable intensification options using agro-ecological approaches such as Conservation Agriculture (CA) and diversified cropping systems to ensure food and nutritional security while sustaining the natural resources. On 2 years mean basis, CA-based cropping system management scenarios (mean of Sc2-Sc7) using diversified crop rotations; increased the system yield by 15.4%, net return by 28.7%, protein yield by 29.7%, while using 53.0% less irrigation water compared to conventional tillage (CT)-based rice-wheat system (Sc1). Maize-mustard-mungbean on permanent beds (PBs) (Sc4) recorded the highest productivity (+ 40.7%), profitability (+ 60.1%), and saved 81.8% irrigation water compared to Sc1 (11.8 Mg ha -1 ; 2190 USD ha -1 ; 2514 mm ha -1 ). Similarly, Sc5 (maize-wheat-mungbean on PBs) improved productivity (+ 32.2%), profitability (+ 57.4%) and saved irrigation water (75.5%) compared to Sc1. In terms of nutritional value, Sc5 was more balanced than other scenarios, and produced 43.8, 27.5 and 259.8% higher protein, carbohydrate and fat yields, respectively, compared to Sc1 (0.93, 8.55 and 0.14 Mg ha -1 ). Scenario 5 was able to meet the nutrient demand of 19, 23 and 32 additional persons ha -1  year -1 with respect to protein, carbohydrate and fat, respectively, compared to Sc1. The highest protein water productivity (~ 0.31 kg protein m -3  water) was recorded with CA-based soybean-wheat-mungbean (Sc6) system followed by maize-mustard-mungbean on PBs (Sc4) system (~ 0.29 kg protein m -3 ) and lowest under Sc1. Integration of short duration legume (mungbean) improved the system productivity by 17.2% and profitability by 32.1%, while triple gains in irrigation water productivity compared to CT-based systems. In western IGP, maize-wheat-mungbean on PBs was found most productive, profitable and nutritionally rich and efficient system compared to other systems. Therefore, diversification of water intensive cereal rotations with inclusion of legumes and CA-based management optimization can be potential option to ensure nutritious food for the dwelling communities and sustainability of natural resources in the region., (© 2022. The Author(s).)

Rural households in South Asia's coastal deltas face numerous livelihood challenges, including risks posed by climatic variability and extreme weather events. This study examines major climate risks, farmers' adaptation strategies, and the factors affecting the choice of those strategies using data collected from 630 households in southwestern coastal Bangladesh. Farmers identified cyclones, excessive rain and flooding, and salinity as direct climate risks. Increased crop diseases/pests and livestock diseases were perceived as indirect risks resulting from climatic variability. Farmers used multiple adaptation strategies against those risks such as modifications in farm management, use of savings and borrowing funds from family and neighbors, and periodically reducing household food consumption. Off-farm employment and seeking assistance from governmental as well as non-governmental organizations (NGOs) were also common adaptation strategies. The results show that male-headed households are more likely to change farming practices and reduce consumption compared with female-headed households that conversely tended to take assistance from NGOs as an adaptation strategy. Ownership of land and livestock, as well as farmers' prior exposure to climate change and educational training, also had a significant effect on the choice of adaptation strategy. Therefore, development interventions and policies that aimed at improving resource endowment and training to farmers on climatic risks and their adaptation strategies can help minimize the impact of climatic risks.

In the Indo-Gangetic Plains of South Asia, the quadruple challenges of deteriorating soil quality, declining groundwater, energy shortages, and diminishing farm profitability threaten sustainability of conventional till (CT)-based cereal production systems. A 5-year study was conducted to evaluate the effect of conservation agriculture (CA)-based management (tillage, crop establishment, residue management, and system intensification through mungbean integration) on energy budget, water productivity, and economic profitability in cereal (rice-wheat, RW/maize-wheat, MW)-based systems compared with CT-based management. In CA systems, crop residues contributed the maximum (~76%) in total energy input (167,995 MJ ha -1 ); however, fertilizer application (nonrenewable energy source) contributed the maximum (43%) in total energy input (47,760 MJ ha -1 ) in CT-based systems. CA-based cereal (rice/maize) systems recorded higher net energy and energy-intensiveness (EI) levels of 251% and 300%, respectively, compared with those of the CT-based rice-wheat system (RW/CT) (295,217 MJ ha -1 and 46.05 MJ USD -1 ), irrespective of mungbean integration. MWMb/ZT+R utilized 204% more input energy, which resulted in 14% higher net energy and 229% higher EI compared with RW/CT. CA-based RW and MW systems enhanced the crop productivity by 10 and 16%, water productivity by 56 and 33%, and profitability by 34 and 36%, while saving in irrigation water by 38 and 32%, compared with their respective CT-based systems, respectively. CA-based system improved net energy, crop productivity, and profitability; therefore, it should be outscaled to improve the soil and environmental quality in north-west India.

Given the increasing scarcity of production resources such as water, energy and labour coupled with growing climatic risks, maize-based production systems could be potential alternatives to intensive rice-wheat (RW) rotation in western Indo-Gangetic Plains (IGP). Conservation agriculture (CA) in maize systems has been widely promoted for minimizing soil degradation and ensuring sustainability under emerging climate change scenario. Such practices are also believed to provide mitigation co-benefits through reduced GHG emission and increased soil carbon sequestration. However, the combined effects of diversified crop rotations and CA-based management on GHG mitigation potential and other co-benefits are generally over looked and hence warrant greater attention. A field trial was conducted for 5-years to assess the changes in soil organic carbon fractions, mineral-N, N 2 O emission and global warming potential (GWP) of maize-based production systems under different tillage & crop establishment methods. Four diversified cropping systems i.e. maize-wheat-mungbean (MWMb), maize-chickpea-Sesbania (MCS), maize-mustard-mungbean (MMuMb) and maize-maize-Sesbania (MMS) were factorially combined with three tillage & crop establishment methods i.e. zero tilled permanent beds (PB), zero-tillage flat (ZT) and conventional tillage (CT) in a split-plot design. After 5-years of continued experimentation, we recorded that across the soil depths, SOC content, its pools and mineral-N fractions were greatly affected by tillage & crop establishment methods and cropping systems. ZT and PB increased SOC stock (0-30 cm depth) by 7.22-7.23 Mg C ha -1 whereas CT system increased it only by 0.88 Mg C ha -1 as compared to initial value. Several researchers reported that SOC & mineral-N fraction contents in the top 30 cm soil depth are correlated with N 2 O-N emission. In our study, global warming potential (GWP) under CT system was higher by 18.1 and 17.4%, compared to CA-based ZT and PB, respectively. Among various maize systems, GWP of MMS were higher by 11.2, 6.7 and 6.6%, compared that of MWMb (1212 kg CO 2 -eq. ha -1 ), MCS (1274 kg CO 2 -eq. ha -1 ) and MMuMb (1275 kg CO 2 -eq. ha -1 ), respectively. The results of our study suggest that CA and diversified crop rotations should be promoted in north-western IGP and other similar agro-ecologies across the globe for ensuring food security, restoration of soil health and climate change mitigation, the key sustainable development goals (SDGs)., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Foliar application of nutrients escalates efficient use of nutrients along with quick response. An experiment was undertaken to study the effect of foliar application of mineral nutrients viz., boron (B), magnesium (Mg) and iron (Fe) sprayed at different growth stages viz., at fruit set and one month after first spray at the experimental orchard of Chaudhary Charan Singh Haryana Agricultural University, Hisar, Haryana during year 2020–21 and 2021–2022. The experiment was conducted in a Randomized Block Design with 21 treatments and 3 replications with a spacing of 6 × 6 m. Foliar sprays with boron, magnesium and iron significantly affected the physio-chemical properties of the fruits. Total soluble solids, TSS acidity ratio, ascorbic acid, total sugar, reducing sugar, non-reducing sugar and pectin content were found to be maximum under the treatment T21 [FeSO4 (0.5%) + H3BO3 (0.5%) + MgSO4 (0.5%)] while in case of titratable acidity was found significantly lowest under the treatment T21 [FeSO4 (0.5%) + H3BO3 (0.5%) + MgSO4 (0.5%)]. Treatments also affected the leaf chlorophyll content and leaf nutrient status significantly. It can be concluded from this study that foliar sprays of boron, magnesium and iron are beneficial for improving fruit quality, leaf chlorophyll content and leaf nutrient status of guava cv. Hisar Surkha. Further, 0.5 per cent each of FeSO4, H3BO3 and MgSO4 foliar sprays two times at one month's interval can obtain the best results in terms of quality of fruits. [ABSTRACT FROM AUTHOR]

During the past two centuries, the world has witnessed a remarkable increase in the atmospheric concentrations of the greenhouse gases (GHGs), namely carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), as a result of human activities after 1750 (preindustrial era). During 1750 the concentrations for these gases were 280 ppm, 715 ppb, and 270 ppb, respectively which increased to 379 ppm, 1774 ppb, and 319 ppb, respectively in 2005. It showed an increase of 0.23, 0.96, and 0.12% annually. The same has further increased to 385 ppm, 1797 ppb, and 322 ppb, respectively in 2008 representing 1.6, 1.2, and 0.9% increase, respectively from 2005 levels at an annual increase of 0.53, 0.43, and 0.31%, annually. Increase in atmospheric CO2 promotes growth and productivity of plants with C3 photosynthetic pathway but the increase in temperature, on the other hand, can reduce crop duration, increase crop respiration rates, affect the survival and distribution of pest populations, and may hasten nutrient mineralization in soils, decrease fertilizer-use efficiency, and increase evapotranspiration. The water resources which are already scarce may come under enhanced stress. Thus, the impact of climate change is likely to have a significant influence on agriculture and eventually on the food security and livelihoods of large sections of the urban and rural populations globally. The developing countries, particularly in South Asia and Latin America, with diverse agroclimatic regions, challenging geographies, growing economies, diverse agricultural production systems, and farm typologies are more vulnerable to the effect of climate change due to heavy dependence on agriculture for livelihood. These regions also are demonstrating poor coping mechanisms to adapt to these challenges, and as a result there is evidence of negative impacts on productivity of wheat, rice, and other crops to varying extent depending on agroecologies. Upscaling of modern technologies such as conservation and climate smart agriculture, judicious utilization of available water for agriculture through microirrigation and water saving technologies, developing multiple stress-tolerant crop cultivars and biotypes through biotechnological tools, restoration of degraded soils and waters, promoting carbon sequestration through alternate production technologies and land use, and conservation of biodiversity must be promoted at regional and country level to ensure durable food and nutritional security. Reliable early warning system of environmental changes, their spatial and temporal magnitude, coupled with policies to support the diffusion of this information, can help interpret these forecasts in terms of their agronomic and economic implications for the benefit of farmers and to provide agriculture-dependent industries and policymakers with more informed options to support farmers. These countries need to formulate both short-term and long-term policies for improvement, sustenance, and protection of natural resources. There is an urgent need for capacity building through international collaboration in order to develop databases and analysis systems for efficient weather forecasting as well as preparing contingency plans for vulnerable areas. The objectives of this paper are to summarize the available information on adaptation strategies and the mitigation options for climate change to meet the food security in South Asia and Latin America. [ABSTRACT FROM AUTHOR]

Conducting farmers participatory field trials at 40 sites for 3 consecutive years in four rice-wheat system dominated districts of Haryana state of India, this paper tested the hypothesis that zero tillage (ZT) based crop production emits less greenhouse gases and yet provide adequate economic benefits to farmers compared to the conventional tillage (CT). In each farmer's field, ZT and CT based wheat production were compared side by side for three consecutive years from 2009–10 to 2011–12. In assessing the mitigation potential of ZT, we examined the differences in input use and crop management, especially those contributing to GHGs emissions, between ZT wheat and CT wheat. We employed Cool Farm Tool (CFT) to estimate emission of GHGs from various wheat production activities. In order to assess economic benefits, we examined the difference in input costs, net returns and cost-benefit analysis of wheat production under CT and ZT. Results show that farmers can save approximately USD 79 ha−1 in terms of total production costs and increase net revenue of about USD 97.5 ha−1 under ZT compared to CT. Similarly, benefit-cost ratio under ZT is 1.43 against 1.31 under CT. Our estimate shows that shifting from CT to ZT based wheat production reduces GHG emission by 1.5 Mg CO2-eq ha−1 season−1. Overall, ZT has both climate change mitigation and economic benefits, implying the win-win outcome of better agricultural practices. [ABSTRACT FROM PUBLISHER]

Almost one-fourth of the global population live in South Asia (SA) countries with 14% of cultivable land. Most of the countries in the South Asian region are facing multiple challenges like high population growth, declining farm land area, and low productivity in primary and secondary sectors leading to limited employment opportunities. Consequently, both availability and access to food are adversely affected. Regions exposed to natural disasters, tribal and the hilly regions of SA are amongst the most vulnerable in terms of food security. Accelerated efforts are required to ensure that conflicts do not exacerbate the already fragile food situation in SA. Despite recent strong gains in economic growth and agricultural productivity, food and nutritional security remains a major concern in SA. The region has the largest concentration of poverty and hunger in the world, with nearly 40% of the world's impoverished and 45% of the world's undernourished people. The enormity of malnutrition in SA can be gauged from the fact that it is the home to nearly two-thirds of the world's undernourished children. More than 56% of the world's low-birth-weight babies are born in SA. Furthermore, food and nutrition security remain major challenges with a large proportion of the world's poor living here and global hunger index (GHI) at 30.9. Overcoming these twin challenges require actions both at the national and regional level. Among production constraints and yield gaps, imbalanced nutrient use is a critical issue in many of the SA countries, with nutrient application focused mainly on nitrogen (N), leaving the possibility for other plant nutrient deficiencies including phosphorus (P) and potassium (K). In some cases, the use efficiency of N may be low due to losses in the form of N2O emissions, a potent greenhouse gas (GHG), or via leaching with the undesirable offsite effects. Among the primary nutrients, K is an essential nutrient for productivity, food quality and numerous functions in the plant system. It plays a major role in activating ~60 enzymes, regulating stomatal functions, controlling water relations especially under rainfed crop production, influencing the water balance of plant systems, and underpinning agronomic productivity and sustainability. Negative K balance in soil under intensive cropping is reported because of low external input and large crop removal, leading to large scale K mining in soils. Declining yield trends were observed in several fertilizer experiments 30-40 years long with continuous application of either N alone or NP without K under both irrigated and rainfed crop production systems in the region. Recent K fertility analysis indicates widespread K deficiency in light-textured alluvial soils, red and lateritic soils beside acid soil types in India, Bangladesh, Sri Lanka, and Pakistan. The countries in SA depend largely on imported K fertilizers. Such imported fertilizer should be utilized most efficiently in the light of limited global K mineral reserves and 93% of world total K exports are from five countries viz. Canada (37.12%) followed by the Russian Federation, Belarus, Germany and Israel. Therefore, the current review addresses issues related to the K supplying capacity of soils in various crop production systems in SA, crop K responses, soil test methods followed, emerging issues in soil K fertility, K balance in major cropping systems and rationalizing K recommendations among crops, soil types and agro-ecological regions. The role of K in balanced nutrition, farm productivity, food and nutritional security in these countries is examined. The review also covers the critical role of K in climate change adaptation, mitigation of nitrous oxide (N2O) emissions and improving overall nitrogen use efficiency (NUE) in the SA region. [ABSTRACT FROM AUTHOR]

The article focuses on intentional use of fires to transform land which has decreased and mentions market-oriented approaches and moral suasion which has been less effective. Topics discussed include polluted air which is health risk factor along with seasonal smog which imposes costs, alternative to crop residue burning and agriculture in northwestern India's Indo-Gangetic plains.