• Energy Research

Conservation agriculture has recently been a hot topic of agricultural research and has generated significant global interest. Conservation agriculture has three core principles: minimal soil disturbance, permanent soil cover, and crop rotations. The research on this topic has also witnessed a boom in recent years as the number of peer-reviewed literature on conservation agriculture is rising exponentially. This study critically examines all the peer-reviewed documents published on conservation agriculture from the 1990s to 2021 and indexed in the web of science core database. The search returned 3023 documents, which were then processed in the R-based bibliometric package for annual scientific production trend, source, author, document, citation, keyword analysis, and co-occurrence networking using VOSviewer. Our findings show remarkable growth in conservation agriculture research in recent times, although it witnessed a shortfall in 2021. Notably, 15 core source journals contribute the most to the field, while 8692 researchers have authored or co-authored at least a document on conservation agriculture. While the USA, India, and Australia are front runners in conservation agriculture research, the spread of the topic is worldwide.

Abstract Maize-based crop rotations are advocated as alternate to rice-based systems in South Asia due to better suitability for diverse ecologies, higher yields with less water use and more palatable maize fodder compared to rice, and increased demand of maize from piggery and poultry industries. Alternate tillage and crop establishment practices are important management strategies for tackling the issues of soil health deterioration and over exploitation of underground water resources, particularly in rice based intensive crop rotations. The conservation agriculture (CA) based tillage and crop establishment practices such as zero tillage (ZT) and permanent raised beds (PB) hold potential to enhance soil organic carbon (SOC), physical and biological properties for sustainability of soil health. Therefore, a long term study was conducted to evaluate the twelve combinations of tillage practices (03) and irrigated intensive maize based crop rotations (04) on organic carbon, physical properties and microbial biomass and enzymatic activities of a sandy loam (Typic Haplustept) soil in north-western India. The tillage practices consisted of ZT, PB and conventional tillage (CT) in main plots and four diversified intensive maize based crop rotations (MWMb: Maize-Wheat-Mungbean, MCS: Maize-Chickpea- Sesbaina , MMuMb: Maize-Mustard-Mungbean, MMS: Maize-Maize- Sesbania ) in sub plots. In this study we analysed the SOC, physical and biological properties of soil at various depths after 7 years of continuous ZT, PB and CT in diversified maize rotations. Compared to CT plots, the soil physical properties like water stable aggregates (WSA) > 250 μm were 16.1-32.5% higher, and bulk density (BD) and penetration resistance (PR) showed significant (P β Glucosidase and Alkaline phosphatase was also recorded in the CA based treatments. Significant (P Sesbania ) with winter legume/cereal in crop rotations were observed on SOC,WSA, BD, PR and K sat at 0–15 and 15–30 cm depths. Interaction between tillage and crop rotations were significant (P

Although nitrogen (N) is the most limiting nutrient for agricultural production, its overuse is associated with environmental pollution, increased concentration of greenhouse gases, and several human and animal health implications. These implications are greatly affected by biochemical transformations and losses of N such as volatilization, leaching, runoff, and denitrification. Half of the globally produced N fertilizers are used to grow three major cereals—rice, wheat, and maize—and their current level of N recovery is approximately 30–50%. The continuously increasing application of N fertilizers, despite lower recovery of cereals, can further intensify the environmental and health implications of leftover N. To address these implications, the improvement in N use efficiency (NUE) by adopting efficient agronomic practices and modern breeding and biotechnological tools for developing N efficient cultivars requires immediate attention. Conventional and marker-assisted selection methods can be used to map quantitative trait loci, and their introgression in elite germplasm leads to the creation of cultivars with better NUE. Moreover, gene-editing technology gives the opportunity to develop high-yielding cultivars with improved N utilization capacity. The most reliable and cheap methods include agronomic practices such as site-specific N management, enhanced use efficiency fertilizers, resource conservation practices, precision farming, and nano-fertilizers that can help farmers to reduce the environmental losses of N from the soil–plant system, thus improving NUE. Our review illuminates insights into recent advances in local and scientific soil and crop management technologies, along with conventional and modern breeding technologies on how to increase NUE that can help reduce linked N pollution and health implications.

Indiscriminate and injudicious application of inorganic fertilizers and irrigation, respectively, cause declines in crop productivity as well as environmental pollution. Therefore, judicious use of organic manures and proper scheduling of irrigation are required for sustainable production of wheat crops. A two-year (2014–2015 and 2015–2016) study was conducted to determine the wheat nutrient uptake, soil moisture, and grain yield as a result of organic manures and irrigation schedule. The experiment was set up with four treatments of organic manure in four subplots with repellents and five irrigation planning treatments in the main plot. The results showed that an irrigation/water ratio of 0.9 irrigation water depth/cumulative pan evaporation (I2) increased grain yield, soil moisture content, and nutrient uptake of wheat (I3) compared to 0.6 IW/CPE during the vegetative period and 0.8 IW/CPE during the reproductive period. According to statistics, it was found that the vegetative period is maintained at 0.8 IW/CPE, and the reproductive period is maintained at 1.0 IW/CPE (I5). Applying 7.5 Mg ha−1 of farmyard manure (FYM) plus 3 Mg ha−1 of vermicompost while employing organic manure increases grain output, soil moisture content, and nutrient content and absorption compared to the control treatment. Therefore, it is concluded that irrigation either at I2 or I5 + FYM at 7.5 Mg ha−1 + vermicompost at 3 Mg ha−1 could be recommended for enhancing grain of wheat cultivation, particularly in the semiarid regions of northwestern India.

Abstract Conservation agriculture (CA) based best-bet crop management practices may increase crop and water productivity, while conserving and sustaining natural resources. Therefore, we evaluated kharif maize performance in 2014 under long-term tillage practices [permanent bed (PB) and zero tillage (ZT)] with conventional till (CT) as main plots and four irrigated maize based systems [maize-wheat-mungbean (MWMb), maize-chickpea- Sesbania (MCS), maize-mustard-mungbean (MMuMb) and maize-maize- Sesbania (MMS)] in sub plots under an ongoing trial established in 2008. In seventh kharif season at fixed plots the growth parameters, yield attributes, yield, water and energy-use efficiency of maize was maximum in ZT plots. The maize growth parameters were significantly ( p ) superior under ZT and PB compared to CT plots. Maize yield attributes viz. cobs m −2 (7.8), cob length (0.183 m), grain rows cob −1 (13.8) and grains row −1 (35.6) were significantly higher in ZT over to CT, however no-significant effect of cropping systems was found on maize growth and yield attributes. ZT registered maximum maize productivity (4589 kg ha −1 ). However, among the cropping sequences, MCS registered highest maize productivity (4582 kg ha −1 ). In maize, the water-use was reduced by 80.2-120.9 mm ha −1 in ZT and PB plots compared to CT which ultimately enhanced the water-use efficiency by 42.0 and 36.6%, respectively. ZT and PB plots registered increased soil organic carbon (SOC) by 3.5-31.8% in different depths (0-0.45 m) and energy productivity by 32.3-39.9% compared with CT. Overall, our long-term results showed that CA based ZT and PB practices coupled with diversified maize based cropping systems found effective for enhancing the maize yield, soil organic carbon, water and energy-use efficiency in North-Western India.

Heat stress (HS) is one of the major abiotic stresses affecting the production and quality of wheat. Rising temperatures are particularly threatening to wheat production. A detailed overview of morpho-physio-biochemical responses of wheat to HS is critical to identify various tolerance mechanisms and their use in identifying strategies to safeguard wheat production under changing climates. The development of thermotolerant wheat cultivars using conventional or molecular breeding and transgenic approaches is promising. Over the last decade, different omics approaches have revolutionized the way plant breeders and biotechnologists investigate underlying stress tolerance mechanisms and cellular homeostasis. Therefore, developing genomics, transcriptomics, proteomics, and metabolomics data sets and a deeper understanding of HS tolerance mechanisms of different wheat cultivars are needed. The most reliable method to improve plant resilience to HS must include agronomic management strategies, such as the adoption of climate-smart cultivation practices and use of osmoprotectants and cultured soil microbes. However, looking at the complex nature of HS, the adoption of a holistic approach integrating outcomes of breeding, physiological, agronomical, and biotechnological options is required. Our review aims to provide insights concerning morpho-physiological and molecular impacts, tolerance mechanisms, and adaptation strategies of HS in wheat. This review will help scientific communities in the identification, development, and promotion of thermotolerant wheat cultivars and management strategies to minimize negative impacts of HS.