The impact of different fertiliser management options and cultivars on nitrogen use efficiency and yield for rice cropping in the Indo-Gangetic Plain: two seasons of methane, nitrous oxide and ammonia emissions

This study presents detailed crop and gas flux data from two years of rice production at the experimental farm of the ICAR-Indian Agricultural Research Institute, New Delhi, India. In comparing 4 nitrogen (N) fertiliser regimes across 4 rice cultivars (CRD 310, IR-64, MTU 1010, P-44), we have added to growing evidence of the environmental costs of rice production in the region. The study shows that rice cultivar can impact yields of both grain, and total biomass produced in given circumstances, with the CRD 310 cultivar showing consistently high nitrogen use efficiency (NUE) for total biomass compared with other tested varieties, but not necessarily with the highest grain yield, which was P-44 in this experiment. While NUE of the rice did vary depending on experimental treatments (ranging from 41% to 73%), 73%), this did not translate directly into the reduction of emissions of ammonia (NH3) and nitrous oxide (N2O). Emissions were relatively similar across the different rice cultivars regardless of NUE. Conversely, agronomic practices that reduced total N losses were associated with higher yield. In terms of fertiliser application, the outstanding impact was of the very high methane (CH4) emissions as a result of incorporating farmyard manure (FYM) into rice paddies, which dominated the overall effect on global warming potential. While the use of nitrification and urease inhibiting substances decreased N2O emissions overall, NH3 emissions were relatively unaffected (or slightly higher). Overall, the greatest reduction in greenhouse gas (GHG) emissions came from reducing irrigation water added to the fields, resulting in higher N2O, but significantly less CH4 emissions, reducing net GHG emission compared with continuous flooding. Overall, genetic differences generated more variation in yield and NUE than agronomic management (excluding controls), whereas agronomy generated larger differences than genetics concerning gaseous losses. This study suggests that a mixed approach needs to be applied when attempting to reduce pollution and global warming potential from rice production and potential pollution swapping and synergies need to be considered. Finding the right balance of rice cultivar, irrigation technique and fertiliser type could significantly reduce emissions, while getting it wrong can result in considerably poorer yields and higher pollution

Long-term trends of direct nitrous oxide emission from fuel combustion in South Asia

An increasing concentration of nitrous oxide (N2O) in the global atmosphere can perturb the ecological balance, affecting the climate and human life. South Asia, one of the world's most populous regions, is a hotspot for N2O emission. Although agriculture traditionally dominated the region, economic activities are rapidly shifting towards industry and energy services. These activites may become the largest emitters of N2O in future. Yet, few attempts have been made to estimate long-term direct N2O emission from fuel combustion for the different energy-consuming sectors in the South Asian region. Therefore, the present study developed a comprehensive sectoral N2O emission inventory for South Asian countries for the time period of 1990–2017, with projections till 2041. It revealed that the average N2O emission from fuel combustion in the South Asia region is about 40.96 Gg yr−1 with a possible uncertainty of ±12 Gg yr−1, showing an increase of more than 100% from 1990 to 2017. Although India is the major contributor, with an average of 34 Gg yr−1 of N2O emissions, in terms of growth, small countries like Bhutan and Maldives are dominating other South Asian countries. Sector-wise, the residential sector contributed a maximum emission of 14.52 Gg yr−1 of N2O but this is projected to reduce by more than 50% by 2041. This is because of the successful promotion of cleaner fuels like liquefied petroleum gas over more polluting fuelwood. Power generation contributed 9.43 Gg yr−1of N2O emissions, exhibiting a maximum growth of 395%, followed by road transport (289%) and industry (231%). Future N2O emissions from transport, power and industry are projected to rise by 2.8, 3.3, and 23.9 times their 2017 estimates, respectively, due to the incapability of current policies to combat rising fossil fuel consumption. Mitigation options, such as replacing diesel and compressed natural gas vehicles with electricity-driven vehicles, can decelerate N2O emissions to 45% by 2041 for road transport. A 41% reduction is possible by displacing coal with renewables in the power and industry sectors. Overall, the South Asian contribution to global N2O emissions has enlarged from 2.7% in 1990 to 5.7% in 2007–2016, meaning there is an urgent need for N2O emission mitigation in the region

Nitrogen Challenges and Opportunities for Agricultural and Environmental Science in India

In the last six decades, the consumption of reactive nitrogen (Nr) in the form of fertilizer in India has been growing rapidly, whilst the nitrogen use efficiency (NUE) of cropping systems has been decreasing. These trends have led to increasing environmental losses of Nr, threatening the quality of air, soils, and fresh waters, and thereby endangering climate-stability, ecosystems, and human-health. Since it has been suggested that the fertilizer consumption of India may double by 2050, there is an urgent need for scientific research to support better nitrogen management in Indian agriculture. In order to share knowledge and to develop a joint vision, experts from the UK and India came together for a conference and workshop on “Challenges and Opportunities for Agricultural Nitrogen Science in India.” The meeting concluded with three core messages: (1) Soil stewardship is essential and legumes need to be planted in rotation with cereals to increase nitrogen fixation in areas of limited Nr availability. Synthetic symbioses and plastidic nitrogen fixation are possibly disruptive technologies, but their potential and implications must be considered. (2) Genetic diversity of crops and new technologies need to be shared and exploited to reduce N losses and support productive, sustainable agriculture livelihoods. Móring et al. Nitrogen Challenges and Opportunities (3) The use of leaf color sensing shows great potential to reduce nitrogen fertilizer use (by 10–15%). This, together with the usage of urease inhibitors in neem-coated urea, and better management of manure, urine, and crop residues, could result in a 20–25% improvement in NUE of India by 2030

Application of hexakisacetonitrile iron (III) perchlorate in organic synthesis

865-866<span style="font-size:12.0pt;font-family: " times="" new="" roman";mso-fareast-font-family:"times="" roman";mso-ansi-language:="" en-in;mso-fareast-language:en-in;mso-bidi-language:ar-sa"="" lang="EN-IN">Iron (III) perchlorate-CH3CN functions as an acid catalyst and promotes Ritter reaction. The reagent is not suitable to bring about oxidative decarboxylation and cleavage of glycols.</span

An expedient synthesis of racemic combretastatin and isocombretastatin

817-821The stilbenoid constituents of Combretum caffrum possess pronounced antineoplastic and antimitotic activities. The most potent agents are R (-) combretastatin 1, and combretastatins A-1 to A-4. A novel and simple method for the synthesis of ±1 and isocombretastatin 5 in which an appropriately substituted 1, 3-diarylpropanoid is transformed into a stilbenoid is described. The key step involves the alkali induced rearrangement of chalcone epoxide 9 to α-hydroxy acid 10 and that is followed by oxidative decarboxylation and reduction

β,β -Dimethylacrylophenones : BF₃.Et₂O-POCl₃ catalysed acylation of phenols using β, β -dimethylacrylic acid

1237-1241Boron trifluoride etherate-phosphoryl chloride reagent is a useful reagent for the condensation between phenols and β, β -dimethylacrylic acid. The main products are acrylophenones. But surprisingly hydroquinone gives mono and diacrylates

Not Available

Not AvailableThe study quantified the generation of surplus crop biomass at district level in three crop growing seasons (kharif, rabi and summer) for all the 662 districts of the country. A total of eleven crops, namely rice, wheat, maize, sugarcane, cotton, pulses (Gram & Tur) and oilseed (groundnut, mustard, soybean and castor) were selected for the study. The crops were selected based on their acreage and total production across the country. The total gross cultivated area of the country is about 195 million hectare. The area under cultivation for the selected eleven selected crops is 137 M ha i.e about 70% of gross cultivated area. The assessment methodology involved four major steps: (1) compilation of area and production statistics of selected crops, (2) estimation of dry biomass generation, (3) development of surplus factors and quantification of surplus biomass generation, and (4) estimation of bioethanol production potential of surplus crop biomass. The crop biomass usage pattern by farmers for their own self as well as the biomass sold to others for industrial or any other usage was compiled to estimate the factors for surplus crop biomass generation. A novelty of this study is that it has developed crop specific season wise and district wise surplus factors and these factors were used to estimate the surplus crop biomass generated by the selected crops in the country. The study also estimated the district wise theoretical bio-ethanol production potential of surplus crop biomass generated by each crop in each season. Of the total gross area under cultivation for the eleven selected crops, 72% area is accounted by rice, wheat, cotton and soybean crops only. These eleven crops generate about 683 million tons (MT) of total dry biomass in the three crop growing seasons. Out of this total annual crop biomass, 59% is generated during kharif season and 39% during rabi season. The remaining about 2% is generated during summer season. After different usages of this crop biomass by farmers, there is still some surplus left which can be utilized in a useful manner. The total annual surplus crop biomass is estimated to be approximately 178 MT which is about 26% of the total dry biomass generated. The season wise surplus biomass is highest in kharif season (72%) and the major crops contributing to surplus biomass are rice sugarcane cotton and soybean. In rabi season wheat, gram, rice and mustard are the crops contributing to the surplus crop biomass. The surplus biomass generated during summer is negligible. In kharif season the States of Punjab, Uttar Pradesh (U.P.), Maharashtra, Tamil Nadu (T.N.), Andhra Pradesh (A.P.), Karnataka, Telangana, Gujarat, Madhya Pradesh (M.P.), and Rajasthan generated high surplus crop biomass. Whereas in rabi season the States of Punjab, U.P., M.P., Maharashtra, Karnataka, Rajasthan, and Haryana generated high surplus crop biomass. The total annual bio-ethanol production potential from this surplus crop biomass generated in the country is 51.35 billion litres from eleven selected crops. The study provides district scale seasons wise crop area, crop dry biomass, surplus biomass and bioethanol maps for each of the eleven crops for use by different stakeholders. It is expected that the outcome of this study shall help in developing an improved policy for 2nd generation biofuel by utilizing surplus crop residues. This will also help India in achieving the goal of bio-ethanol blending with gasoline.Technology Information, Forecasting and Assessment Council (TIFAC

Synthesis of hormothamnione and 6-desmethoxyhormothamnione

278-283The antineoplastic styrylchromones hormothamnione 1 and 6-desmethoxyhormothamnione 2 are readily prepared by selective and simultaneous demethylation and debenzylation of chromones 3 and 4 using excess AlCl3-NaI in CH3CN

Agricultural and agro-processing wastes as low cost adsorbents for metal removal from wastewater: A review

647-658This study reviews the use of agricultural and agro-processing industry wastes as metal adsorbents from wastewater. Modified materials displayed better adsorption capacity and capability of some was comparable with that of commercial activated carbons and synthetic resins. Agricultural wastes are low-cost adsorbents and can be viable alternatives to activated carbon for treatment of metal-contaminated wastewate