Search

IntroductionClimate change significantly impacts food production by influencing crop growth and soil processes. Rising atmospheric CO2 levels and temperatures may affect reactive nitrogen losses from cultivated soils. This study aimed to quantify the effects of nitrification and urease inhibitors on reactive nitrogen losses from wheat soils in the context of elevated CO2 and temperature interactions.MethodsAn experiment was conducted in open top chambers for two consecutive years to quantify the effect of nitrification and urease inhibitors on ammonia (NH3), and nitrous oxide (N2O) emissions in wheat under elevated carbon dioxide (EC), elevated temperature (ET) and their interaction (ECT). The carbon dioxide (CO2) concentration ranged from 552 to 568 ppm in the EC treatment, while the average temperature was 2.1–2.5°C higher in ET treatment than ambient (AMB).Results and discussionThe N2O–N emission increased under ECT than ambient. Use of neem oil coated urea (NOCU) reduced the N2O–N emission by 10.3%, whereas, Limus coated urea reduced N2O–N emission by 14% as compared to prilled urea treatment under ECT. NH3–N emission from wheat soil also increased under ECT treatment as compared to AMB. Application of N through Limus, reduced NH3–N emission from wheat by 35.7–36.8% when compared with NH3–N emission from prilled urea ECT condition. Elevated temperature reduced grain weight by 7.6%. The grain N content reduced by 10.9% with prilled urea under ECT. The application of NOCU and Limus increased grain N by 6 and 9%, respectively, as compared to urea under ECT interaction. The application of nitrification and urease inhibitors may reduce reactive nitrogen losses and enhance nitrogen use efficiency under future climatic conditions.

Abstract Introduction Nitrogen use efficiency (NUE) is lower for South Asia than for most other regions of the world, and average crop NUE is on the decline in India. This inefficient use of nitrogen fertilizers has implications for agricultural productivity and environmental sustainability. Materials and Methods Using data from 14,669 farmers in India, this paper examined the determinants of synthetic fertilizer and manure adoption and intensity of use for rice (Oryza sativa L.) production. The latter was assessed through fertilizer expenditure rather than the traditional weight‐based method. A double hurdle model was estimated. Results The study showed that farmers' decisions to adopt fertilizer or manure and the decision on use intensity were independent. Both synthetic fertilizers and manure adoption were influenced by common drivers such as access to financial resources through instruments like the Kisan Credit Card and loans, expenditure on irrigation and labour, and geographical location. In terms of barriers, the likelihood of adoption of both synthetic fertilizer and manure was lower among landowners and paddy area cultivated. The intensity of fertilizer and manure use was higher for older farmers and was positively influenced by expenditure on labour but negatively influenced by ownership of livestock. Also, synthetic fertilizers and manure use intensity were determined by regional temperature and geographical zones. Conclusion The results of this study are useful for targeted interventions to promote sustainable fertilizer use with a focus on following recommendations in zones or among demographic groups that are currently more likely to have a high intensity of use. Similarly, the findings inform support towards increased adoption and sustainable use where fertilizer is underutilised.

IntroductionGlobal food security is challenged by the increasing levels of air pollutants like ozone (O3) through their impacts on crop productivity. The present study was conducted to quantify the interactive effect of elevated ozone (O3) and carbon dioxide (CO2), on different rice varieties in northern India.MethodsAn experiment was conducted in Genetic H field, Environment science, IARI for two consecutive years (2020 and 2021) during the kharif season, to quantify the impact of elevated O3 and CO2 interaction on productivity, and plant N in three rice varieties (Pusa basmati 1121, Nagina 22, IR64 Drt1) under different nitrogen (N) management practices. Rice crop was grown in Free Air Ozone-Carbon dioxide Enrichment rings (FAOCE) rings with two levels of O3 (elevated 60 ±10ppb and ambient) and two levels of CO2 (elevated, 550±25 ppm and ambient) concentration and their interaction with two N fertilizer treatments i.e., 100% RDN (recommended dose of N) and 125% RDN.Results and discussionElevated O3 significantly decreased physiological parameters like photosynthesis rate, stomatal conductance and transpiration rate of the crop. Grain yield reduced by 7.2-7.5%, in Pusa Basmati 1121 and from 6.9-9% in IR64 Drt1 varieties in elevated O3 treatment as compared to ambient treatment. Yield reduction in Nagina 22 variety was not significant in elevated O3 treatment. Elevated CO2 concentration of 550 ppm was able to fully compensate the yield loss in Nagina 22 variety and partially compensate (3.9-8.0%) in Pusa Basmati 1121 and IR64 Drt1 varieties. Grain N concentration in rice varieties decreased by 10.8-14.7% during first year and by 7.8-20.6% during second year in elevated O3 plus CO2 interaction treatment than ambient. Grain N uptake also decreased (13.2-17.1% in first year and 4.5-22.8% in second year) in elevated O3 plus CO2 interaction treatment as compared to ambient. Application of additional 25% of recommended dose of N improved grain N concentration, grain N uptake as well as available N of soil as compared to 100% RDN treatment in elevated O3 plus CO2 interaction treatment. Additional 25% N dose could help in sustaining rice productivity and quality under elevated O3 and CO2 condition.

IntroductionThere is a global priority to ensure food security, environmental conservation and sustainability. The adoption of inputs such as organic manures, biofertilisers, and biopesticides has been widely promoted as a way to enhance agricultural sustainability, yet their adoption rates remain notably low. The study examines the determinants and impact of the adoption of multiple sustainable inputs by paddy farmers in India. The study also examines the drivers behind the intensity of their adoption and their technical efficiency.MethodsThe study utilises the survey dataset on paddy farmers from “Situation Assessment of Agricultural Households and Land and Livestock Holdings of Households in Rural India” of the 77th National Sample Survey (NSSO) round. The reference period for data collection was the agricultural year from July 2018 to June 2019. The analytical methods employed include the Multivariate Probit and Ordered Probit models, Seemingly Unrelated Regression, Regression Adjustment model, and Stochastic Frontier method.ResultsThe empirical findings reveal that the adoption and intensity of sustainable inputs depend significantly on factors such as the household head’s age and education, household size, and access to extension services. Adopting sustainable inputs has significant benefits, such as increased harvest value. However, the currently available technical advisory services are limited in effectively promoting the expenditure on sustainable inputs. Technical efficiency analysis underscores the potential for improvement and the importance of utilising optimal input levels. The research findings provide strong evidence in favour of advocating for the use of sustainable inputs in paddy farming.

Achieving high-yielding crops while also improving nitrogen use efficiency is a significant challenge for agricultural production in Bangladesh. We investigated the impacts of applying nitrogen (N) using different management options in wetland rice on a calcareous dark gray soil over three seasons. These included (1) the recommended dose of available N as prilled urea, (2) the recommended N dose plus 25% extra of available N as prilled urea, (3) 25% less than the recommended dose of available N as prilled urea, (4) the recommended dose of prilled urea in 2 t ha−1 cow dung, (5) the recommended dose as urea super granules (USGs) by deep placement, (6) 4 t ha−1 biochar with the recommended dose of prilled urea, and (7) Zero N. It was found that the growth, yield, and N use efficiency (NUE) were significantly different from the results obtained for prilled urea in all the alternative fertilizer options. The deep placement of USG consistently increased plant height, total number of tillers per plant, effective tillers per plant, chlorophyll content, panicle length, grains per panicle, and 1000-grain weight. The yield increases over recommended prilled urea were 5.22% for USG followed by biochar with the recommended dose. Similarly, using the deep placement of USG gave the highest yield and harvest index. In addition, compared to the recommended dose of prilled urea, the deep placement of USG increased NUE by 13%, agronomic N efficiency by 20%, and recovery N use efficiency by 19%. This suggests the rate of N application could be reduced by up to 8% without impacting yield by using deep placement of USG instead of prilled urea. The cost–benefit ratio was higher for the deep placement of USG than all other treatments. Biochar with the recommended dose of prilled urea also showed good results in terms of growth, yield, and NUE (41.8, 43.0, and 41.7, respectively, during three sequential years), but the extra cost of the biochar reduced the cost–benefit ratio. These findings suggest that the deep placement of USG is the best option for improving the yield of rice while also improving N use efficiency.

Conservation agriculture (CA) practices like zero-till and residue retention along with nitrogen management is vital for improving degraded soil health and optimizing the yield potential of wheat (Triticum aestivum L.) crop. Present study was carried out during winter (rabi) seasons of 2021–22 and 2022–23 at ICAR-Indian Agricultural Research Institute, New Delhi for optimizing wheat productivity in a conservation agriculture-based cotton (Gossypium herbaceum L.)-wheat system. The experiment was laid out in a randomized complete block design (RCBD) with three replications consisting of combination of 3 different crop establishment methods, viz. permanent broad bed (PBB), permanent narrow bed (PNB) and zero-till flatbed (ZTFB) with residue (R) and without residue along with 2 doses of nitrogen (75N, 100N) and conventional tillage (CT). The CA-based practices showed overall superior response in terms of growth, yield and nutrients uptake of wheat than CT. Among them, the PBBR100N resulted in significantly higher plant height, leaf area index, dry-matter accumulation, crop growth rate, and relative growth rate compared to PNB, PBB, ZTFB and CT. This treatment led to significantly higher grain (16.2–19.4%) and straw (9.6–11.6%) yields than CT. The net returns and benefit cost ratio (23.4% and 27.9%) were also higher than that in CT. Again, in this treatment, N uptake by wheat crop was higher by 85%, P uptake by 53.1%, and K uptake by 40.1%, and available soil N, P and K by 16.1, 25.3 and 43.7%, respectively than CT. Therefore, the study suggests that the adoption of CA-based practices with broad bed in Indo-Gangetic Plains will not only enhance the productivity of wheat but also result in improved soil health by restoring soil fertility.

The use of inhibitors retain nitrogen as ammonium in soil, giving plants ample time for its uptake. This can reduce nitrous oxide (N2O) emissions, but extended retention may increase ammonia (NH3) volatilization. This study assessed the efficacy of coated urea fertilizers in reducing greenhouse gas (GHG) emissions and NH3 volatilization in rice fields. A field experiment with Pusa 44 rice in the kharif seasons of 2019 and 2020 compared unfertilized control (No N), prilled urea (PU), nitrification inhibitors (NIs): neem oil-coated urea (NCU), karanj oil-coated urea, and dual inhibitor (DI: Limus + NCU). The coated urea fertilizers were analysed with scanning electron microscopy, fourier transform infrared spectrometry, and energy-dispersive spectroscopy. Compared to PU, DI reduced N2O emissions by 23.7%, methane by 11.9%, and NH3 by 29.8%. DI also reduced NH3 emissions by 36–39% compared to other NIs. Overall, DI can lower the global warming potential of rice cultivation in trans Indo-Gangetic plains region by 17.1% for both direct and indirect emissions, suggesting its significant potential to reduce India's contribution to total agricultural GHG emissions.

An experiment was conducted during 2020 and 2021 at ICAR-Indian Agricultural Research Institute, New Delhi, to study the interactive effect of nutrient and PGPR (Plant growth promoting rhizobacteria) on growth and yield of chickpea (Cicer aeritinum L.) cv. Pusa 3043 under ambient and elevated levels of ozone in FAOE (Free air ozone enrichment). A loss of 15–16% in dry matter production was observed under elevated ozone (EO3) when compared to ambient ozone (AO3) conditions. Seed treatment with PGPR was found to compensate for this loss as an increase in seed yield 18–19% was observed over untreated seeds. In terms of seed yield, the PGPR treatments with 75% nitrogen showed significant improvement compared to the recommended dose of fertilizer (RDF) application. A yield increase of 12% and 14% was observed with PGPR like RPAN8 (Anabena laxa) and An-Rh (Anabena torulosa with Mesorhizobium ciceri) (chickpea rhizobium) respectively, suggesting an advantage of an–Rh over RPAN8 under EO3. A combination of both PGPRs outperformed the individual PGPR, showing a 19% yield increase over RDF. This proves the potential of seed treatment with PGPR (RPAN8 and An-Rh) in ameliorating tropospheric ozone-induced stress in chickpea plants.

The impact of climate change on methane (CH4) emissions from rice production systems in the Coimbatore region (Tamil Nadu, India) was studied by leveraging field experiments across two main treatments and four sub-treatments in a split-plot design. Utilizing the closed-chamber method for gas collection and gas chromatography analysis, this study identified significant differences in CH4 emissions between conventional cultivation methods and the system of rice intensification (henceforth SRI). Over two growing seasons, conventional cultivation methods reported higher CH4 emissions (range: from 36.9 to 59.3 kg CH4 ha−1 season−1) compared with SRI (range: from 2.2 to 12.8 kg CH4 ha−1 season−1). Experimental data were subsequently used to guide parametrization and validation of the DeNitrification–DeComposition (DNDC) model. The validation of the model showed good agreement between the measured and modeled data, as denoted by the statistical tests performed, which included CRM (0.09), D-index (0.99), RMSE (7.16), EF (0.96), and R2 (0.92). The validated model was then used to develop future CH4 emissions projections under various shared socio-economic pathways (henceforth SSPs) for the mid- (2021–2050) and late (2051–2080) century. The analysis revealed a potential increase in CH4 emissions for the simulated scenarios, which was dependent on specific soil and irrigation management practices. Conventional cultivation produced the highest CH4 emissions, but it was shown that they could be reduced if the current practice was replaced by minimal flooding or through irrigation with alternating wetting and drying cycles. Emissions were predicted to rise until SSP 370, with a marginal increase in SSP 585 thereafter. The findings of this work underscored an urgency to develop climate-smart location-specific mitigation strategies focused on simultaneously improving current water and nutrient management practices. The use of methanotrophs to reduce CH4 production from rice systems should be considered in future work. This research also highlighted the critical interaction that exists between agricultural practices and climate change, and emphasized the need to implement adaptive crop management strategies that can sustain productivity and mitigate the environmental impacts of rice-based systems in southern India.

A field experiment was conducted during rainy (kharif) 2022 (July 2022–October 2022) and winter (rabi) 2022–23 (November 2022–March 2023) seasons at ICAR-Indian Agricultural Research Institute, New Delhi to evaluate a series of Zn and P solubilizing microbial culture enriched nanoclay biopolymer composite (NCBPC) loaded with nitrogenous fertilizer (urea) and the efficiency of the products for maize (Zea mays L.) and wheat (Triticum aestivum L.). Experiment consisted of 10 treatments, viz. T1, Control; T2, 100% N though urea; T3; T5; T7; and T9, 75% N as urea loaded NCBPC-A (prepared using acrylic acid + acrylamide + mango kernel flour) alone or along with P or Zn or P + Zn solubilizers; T4; T6; T8 and T10, 75% N as urea loaded NCBPC-B (prepared using acrylic acid + acrylamide + maize flour) alone or along with P or Zn or P + Zn solubilizers in a randomized block design (RBD) and replicated thrice. In both maize and wheat crop, highest grain (5.09 and 5.32 t/ha) and straw yield (6.56 and 7.45 t/ha), apparent N recovery (51.26 and 47.26%) and agronomic efficiency (12 and 13.3 kg grain yield obtained/kg N application) were obtained in treatment T10 followed by T9. In addition, total N uptake significantly enhanced by 20.1–28.4% in maize and 22.1–30.8% in wheat (T9 and T10); apparent nitrogen recovery (ANR) improved by 12.9–18.2 and 15.2–21.1% and agronomic efficiency (AE) triggered by 19.5–21.2 and 15.4–20.8% in maize and wheat crops respectively, under T9 and T10 treatments over standard urea fertilization (T2). Thus, the study concludes that, 25% N requirement could be cut down through application of 75% N (urea) loaded NCBPCs in conjunction with Zn or P or Zn + P solubilizing microbial culture as compared to sole urea application under maize-wheat cropping system.

A field experiment was conducted during rainy (kharif) seasons of 2020–21 and 2021–22 at the research farm of ICAR-Indian Agricultural Research Institute, New Delhi to assess the effects of nitrogen and residual sulphur (S) on maize crop in the 11th year of a long-term conservation agriculture (CA)-based maize (Zea mays L.)-Indian mustard [Brassica juncea (L.) Czern.] cropping system. The CA-based practice CA3 [ZT maize (ZTMz) + mustard residue (MsR) + brown manuring (BM) – ZT mustard (ZTMs) + maize residue (MzR)] resulted in greater maize plant height and dry weight than other CA and CT systems except CA4 [ZTMz + mungbean residue (MbR) – ZTMs + MzR – ZTMb + MsR], which had comparable plant height and dry weight. The CA3 increased maize dry weight by 9% and 11.7% over CT in 2020–21 and 2021–22, respectively. On the contrary, CA4 exhibited highest root length, root mass, and root volume densities in both years, and CA3 was comparable. It gave significantly higher grain yield than other treatments except CA3 and CA2 (ZTMz + MsR- ZTMs + MzR), which were comparable. The 100% and 75% recommended dose of N gave comparable grain yield under all CA-based treatments, indicating a saving of 25% N (~37.5 kg N/ha), mainly under CA practices. This highlights N economization over times in CA system. The 100% and 50% S applied to mustard could not show any significant residual effect on maize grain, stover and biological yields. Interactions between CA practices and N treatments for grain yield was significant but between CA and residual S, treatments were statistically similar. Thus, this study underscores the importance of CA framework for enhancing yield and income through better N and S management/savings in maize-mustard system.

Abstract Delayed sowing of maize hybrids could exacerbate the capability of maximizing the yield potential through poor crop stand, root proliferation, nutrient uptake, and dry matter accumulation coupled with the inadequate partitioning of the assimilates. This study appraised the performance of five recent maize hybrids viz., PMH-1, PJHM-1, AH-4158, AH-4271, and AH-8181 under timely and late sown conditions of the irrigated semi-arid ecologies. Timely sowing had the grain and stover yields advantage of 16–19% and 12–25%, respectively over the late sown maize hybrids. The advanced hybrids AH-4271 and AH-4158 had higher grain yields than the others. During the post-anthesis period, a greater dry matter accumulation and contribution to the grain yield to the tune of 16% and 10.2%, respectively, was observed under timely sown conditions. Furthermore, the nutrient acquisition and use efficiencies also improved under the timely sown. The nutrient and dry matter remobilization varied among the hybrids with AH-4271 and PMH-1 registering greater values. The grain yield stability index (0.85) was highest with AH-4158 apart from the least yield reduction (15.2%) and stress susceptibility index (0.81), while the maximum geometric mean productivity was recorded with the AH-4271 (5.46 Mg ha−1). The hybrids AH-4271 and PJHM-1 exhibited improved root morphological traits, such as root length, biomass, root length density, root volume at the V5 stage (20 days after sowing, DAS) and 50% flowering (53 DAS). It is thus evident that the timely sowing and appropriate hybrids based on stress tolerance indices resulted in greater yields and better utilization of resources.

Sustainability of contemporary crop establishment and management practices is questioned due to soil degradation, higher carbon emission and declining soil productivity. Hence, this study was conducted to address the impacts of conservation agriculture (CA) practices like permanent broad beds (PBB), permanent narrow beds (PNB) and zero tilled flat beds (ZT) with residue retention on soil organic carbon (SOC) protection within aggregates in the Indo-Gangetic Plains (IGP). Compared to conventionally tilled (CT) plots, the total SOC content was ∼27%–33% higher in the CA plots on equivalent mass basis. The soil physical properties, such as soil aggregation and mean weight diameter were considerably improved under the CA practices. The macroaggregates were ∼41, 37% and 27% higher in the PBB with residue (PBB + R), PNB with residue (PNB + R) and ZT with residue (ZT + R) plots (CA plots), respectively, than the CT plots in the surface soil (0–15 cm). The plots under PBB + R had ∼31% higher microaggregates within macroaggregates than the CT plots (24.4 g 100 g−1) soil. An increase in SOC content by ∼72, 55% and 69% was observed in the PBB + R, PNB + R and ZT + R plots over the CT plots in microaggregates within macroaggregates (3.02 Mg ha−1). However, plots under PBB + R, PNB + R and ZT + R had only ∼11, 3% and 23% more SOC within silt + clay fraction, respectively, than CT plots (5.85 Mg ha−1). Thus, SOC stabilization within microaggregates inside macroaggregates was the major mechanism, and not the chemical stabilization within silt + clay, of C sequestration under CA. As aggregate-associated carbon is an ecosystem property that strongly affects organic carbon stabilization, water holding capacity and resistance to erosion, growing maize/cotton–wheat system under PBB + R practice is a viable option for carbon sequestration in the IGP and similar agro-ecologies.

An experiment was conducted during 2020–21 and 2021–22 under FACE (Free air concentration enrichment) by growing PDZM 31 (Pusa Double Zero Mustard 31) genotype under different treatments (elevated ozone, carbon dioxide, their interaction, and ambient). The aim of the study was to assess the impact of elevated ozone and carbon dioxide interaction on the growth and yield of Indian mustard [Brassica juncea (L.) Czern.]. Growth characteristics (Crop growth rate, Absolute growth rate, Specific leaf area, Specific leaf weight, Dry weight of Biomass, Plant height, and no. of leaves) and yield attributes were negatively impacted under elevated ozone during different growth stages of Indian mustard followed by an increased growth under elevated CO2. In seed yield under interaction treatment, the elevated CO2 ameliorates the negative effects of elevated ozone by about 3.85% and 4.27% in both years.

The continuing decline in water resources under the ever-changing climate compels us to re-orient our focus to a more sustainable practice. This study investigates the performance of Triticum aestivum wheat genotypes viz. HD-2967, HD-3086, HD-3249, DBW-187, and HD-3226 under well- and deficit-watered conditions for their root-traits, biomass and nitrogen accumulation and remobilization, and water use efficiencies, grown in PVC-tubes. The genotypes HD-2967, HD-3086, HD-3249, DBW-187, and HD-3226 under well-watered (WW) resulted in 36, 35, 38, 33, and 42% more grain yield compared to deficit-watered (DW). Among the genotypes, HD-3249 had the highest grain yield under both well- and deficit-watered conditions. Compared to DW, the WW had 28%, 30%, and 28% greater root length, biomass, and root length density at flowering {102 days (d), Z61}, while among the genotypes, HD-3249 had relatively greater root-traits. At flowering (Z61) and maturity (132 d, Z89), genotypes under WW accumulated 30-46% and 30-53%, respectively greater shoot biomass over the DW. Furthermore, the shoot biomass remobilised for HD-2967, HD-3086, HD-3249, DBW-187, and HD-3226 under the WW was 32, 37, 39, 35, and 35% greater than the DW. The nitrogen partitioning to different plant parts at flowering (Z61) and maturity (Z89) was significantly greater with the WW than with DW. The total nitrogen- remobilized and contribution to grain-N under the WW was 55, 58, 52, 53, 58% and 9, 19, 15, 17, 17% greater than the DW for the genotypes HD-2967, HD-3086, HD-3249, DBW-187, and HD-3226. The irrigation water use efficiency (WUE) at flowering (Z61) was more under the deficit-watered, but the biomass and grain total WUE was improved with the well-watered condition. Hence, it is apparent that proper scheduling of irrigation and N applications, along with the adoption of a genotype suited to a particular environment, will result in better WUE and grain yields, along with better utilization of scarce resources.

Healthy soils are the foundation for producing healthy food and creating a healthy environment. Therefore, we assessed the changes in the physical and chemical properties of soil, and their long-term impact on yield, quality, and nutritional status of rice grains in an organic basmati rice-based cropping system in a typic Ustchrept Soil of India. The experiment was laid out in a strip plot design with three replications. The vertical strips consisted of two rice-based cropping systems, namely, basmati rice-wheat-mung bean (RWM) and basmati rice-wheat-sesbania (RWS), whereas seven combinations of different organic materials and biofertilizers (BF) were assigned to horizontal strips, viz., control (no manure application), farmyard manure (FYM), vermicompost (VC), FYM + crop residues (CR), VC + CR, FYM + CR + BF, and VC + CR + BF. The results revealed that soil moisture content (SMC), soil organic carbon (SOC), soil total N, and soil available P, Fe, Zn, Mn, and Cu were significantly higher under the RWS system than in RWM. The application of organic manures either alone or in conjunction with CR and BF significantly lowered the soil pH (∼3.0%), EC (43.1%–45.8%), and BD (3.3%–9.2%) as compared to the control. Water holding capacity (WHC), SMC, and SOC were increased by 5.7%–14.7%, 8.7%–49.3%, and 35.3%–76.5%, respectively under single or co-application of FYM/VC with CRs and BFs as compared to control. Similarly, sole or conjoint application of organic manures, CR, and BF significantly enhanced the soil available macro (N, P, and K) and micro (Fe, Zn, Mn, and Cu) nutrients over the control. Grain yield, protein content, N uptake, and cooking quality parameters were significantly higher under the RWS system than under RWM. However, the Zn concentration and its uptake by grains were significantly higher under the RWM system over RWS. The grain yield was significantly increased by 25.8%–49.2% under different organic nutrient management options over control. The single or conjoint application of FYM/VC with CR and BF increased the hulling, milling, head rice recovery, and protein concentration in grain by 9.4%–9.8%, 23.2%–28.4%, 22.7%–25.5%, and 9.6%–10.7%, respectively over control. The concentration of N, P, K, Fe, Zn, Mn, and Cu was significantly improved by 9.7%–11.3%, 45.5%–63.6%, 16.7%–20.8%, 66.9%–74.1%, 72.9%–81.9%, 87.1%–97.0%, and 48.9%–67.2%, respectively under co-application of FYM/VC with CR and BF compared to control. Thus, our results indicate that improved soil properties could significantly increase the physical and nutritional quality of basmati rice grain. Therefore, adopting basmati rice-based cropping systems with different organic nutrient sources can sustain soil health, end global hunger, produce nutritious food, and create a healthy environment.

Irrigation is one of the largest consumers of fresh water in the agricultural sector. Surface irrigation is one the most widely adopted method of irrigation due to its simplicity and low energy requirement. Although, it is mostly associated with poor irrigation application efficiency mainly due to deep percolation and uneven distribution of irrigation water. A study was conducted in closed-end level basin layout in loamy soil to establish and test an Internet of Things (IoT) based system through a wireless connection between the automatic check gate and soil moisture sensors which can be operated remotely based on real-time soil moisture status. An attempt had been made to identify the suitable location of the sensor in the basin layout for improving irrigation application efficiency. An aluminium automatic-check gate fitted in an iron frame was placed in the concrete water supply channel to control the water flow. Three capacitance-based soil moisture sensors were placed at 25%, 50% and 75% of field length (i.e., 15 m, 30 m and 45 m) at 37.5, 15 cm and 7.5 cm depth, respectively. A wireless communication network was established between capacitance-based soil moisture sensors and an automatic check gate through the LoRa module and GSM module. The software used for automatic control of the check gate in this study was Croplytics® by Agsmartic. The system was tested for nine irrigation events under bare soil conditions. Three different operational schedules based on different soil moisture sensor placement had been tested under 40%, 30% and 20% soil moisture deficit conditions. The results suggested that the best location of sensors for closing the system would be at 37.5 cm depth placed at 25% length from the inlet in higher soil moisture deficit condition and at 7.5 cm depth placed at 75% length in low moisture deficit condition. Overall, the irrigation application efficiency was improved up to 86.6% with automation.

Potential methane-oxidizing-plant growth-promoting yeast was isolated and characterized during 2017-18 at the ICAR-Indian Agricultural Research Institute, New Delhi. Yeast isolates belonging to the genus Meyerozyma guilliermondii were isolated from five major flooded paddy growing regions of India. Among all the isolates, Meyerozyma guilliermondii KAS-143 efficiently oxidized methane up to 57.64% ± 0.83 in 6 d under in vitro conditions. It also produced a significant quantity of phytohormone IAA and solubilized P, K, and Zn. Meyerozyma guilliermondii KAS-143 can be used for devolving potential inoculants for flooded paddy which can not only promote plant growth but also simultaneously reduce methane emission by its oxidation.

Contrasting tillage and land configuration have important roles in porosity and pore size distribution (PSD), which in turn affects the carbon mineralization in soil. Information on the effects of these treatments on PSD and subsequent carbon mineralization is very limited. Hence, an attempt was made to evaluate the long-term impact of soil tillage and land configurations on the distribution of soil pores and its relationship with soil carbon mineralization under a maize (Zea mays)-wheat (Triticum aestivum) rotation. There were five treatments, that is, conventional tillage, (CT); permanent broad bed, (PBB); PBB + residue (R); zero tillage, (ZT); and ZT + R. Soil pores were quantified by X-ray computed tomography (μ-CT). The conversion of CT to ZT and PBB with or without residue retention (+R) resulted in the reduction of pores >60 μm diameter and was mostly due to a reduction in the number of larger size macro-pores (>110 μm). This resulted in restricted drainage. However, under these practices, pores with larger diameters (60–110 μm) facilitated soil aeration. The total organic carbon (TOC) was 15–48% and 17–47% higher under PBB, PBB + R, ZT, and ZT + R than that under CT in the 0–5 and 5–15 cm layers. The highest MWD (1.01 mm) was in the plots under PBB + R, and the lowest was in the CT plots, and all residue-retained plots (ZT + R and PBB + R) had a higher MWD than residue removal plots (ZT and PBB). Relative to CT, soil C mineralization rates in 0–5 and 5–15 cm soil depths were 63 and 55% higher in the alternate tillage practices, respectively, and the highest value occurred in PPB + R treatments. Increased labile C concentrations were indicative of greater mineralization and were correlated with pores >60 μm, particularly in the size range 110–500 μm and TOC concentrations of 0–15 cm soil layer. Thus, the transition to alternate tillage from the conventional tillage enhanced soil organic carbon concentration (16–47.5%), improved soil structure, reduced the diameter of pores up to >60 μm, and facilitated C mineralization by altering the pore size distribution of soil under a maize-wheat system in the IGP.

Global warming impacts of N use in Indian agriculture since 1960 was estimated for 20- and 100-year time scales using equation-based empirical method. During 2014, total Warming in terms of global temperature change potential (GTP) for a 20-year time scale (GTP20) was assessed as 217.31 ± 17.74 Tg CO2e, and for a 100-year time scale (GTP100) was 217.78 ± 17.78 Tg CO2e. N2O contributed 90% and 99%of the GTP20 and GTP100, respectively. Total cooling impacts were 94.86 ± 7.75 and 50.36 ± 4.11 Tg CO2e on GTP20 and GTP100, respectively. Aerosols of NH3 and NOx, NOx-induced O3 and CH4 alteration, and N-induced C sequestration contributed 41, 6 and 51%, respectively, to GTP20, however, N-induced C sequestration contributed about 99% to GTP100. Net warming impacts were 122.45 ± 10.00 and 167.42 ± 13.67 Tg CO2e on GTP20 and GTP100, respectively. Net warming impacts were lowered by 10% and 1% compared to total warming, and 37% and 23% compared to warming caused by N2O alone, for GTP20 and GTP100, respectively. Usually, to estimate the global warming impacts of N use in agriculture, the warming effects of only N2O emission are considered. However, both warming and cooling impacts should be considered to capture the net impacts of N use in agriculture on climate change.

An experiment was conducted by growing Pusa 44 rice (Oryza sativa L.) variety under different treatments: Ambient, Elevated O3 (EO3: 60 ± 10 ppb), Elevated CO2 (ECO2: 550 ± 10 ppm) and Elevated CO2 and O3 (550 ± 10 ppm CO2 and 60 ± 10 ppb EO3) in free air carbon dioxide and ozone enrichment facility (FACE-O3) with the objective to assess the impact of elevated tropospheric ozone (O3) and carbon dioxide (CO2) interaction on growth and yield of rice. The crop was exposed to elevated levels of gases from transplanting to maturity. EO3 was found to be having a negative impact on all the growth parameters at vegetative, anthesis and maturity stages. ECO2 was found to be having a compensatory effect over EO3 for the different growth parameters. On an average the compensatory effect of ECO2 over EO3 on yield was about 40% and negative impact of elevated O3 over control was around 26% in both the years.

Due to its lower water requirement, methane emission and soil degradation, a maize–wheat rotation (MWR) may be a more attractive alternative to rice–wheat rotation (RWR), in the upper Indo-Gangetic plains (IGP) of India. However, N2O emission from MWR needs to be quantified to propose management practices for N2O mitigation. A field experiment was conducted at the Indian Council of Agricultural Research-Indian Agricultural Research Institute (ICAR-IARI), New Delhi, to assess the impacts of various N sources on N2O emission and its mitigation from the MWR. Six treatments –N0 (control), urea, urea + farmyard manure (FYM), FYM, urea + nitrification inhibitor (NI) and neem oil coated urea (NOCU) were investigated during 2012–2014. Results show ranges of N2O-N emissions from MWR of 0.59–0.69, 1.82–1.86, 1.81–1.85, 1.71–1.77, 1.38–1.52, 1.57–1.61 during 2012–2013, and of 0.62–0.68, 1.86–1.90, 1.78–1.84, 1.72–1.76, 1.40–1.46, 1.52–1.60 during 2013–2014, for N0, urea, urea + FYM, FYM, urea + NI and NOCU treatments, respectively. The 2-year pooled N2O-N emission of MWR decreased by 23% in urea + NI and by 16% in NOCU with higher grain yield as compared to conventional urea application. Application of FYM with urea and FYM alone also reduced N2O-N emission; however, the grain yields of these treatments were decreased. Thus, the study suggests that the application of NOCU and NI with urea can mitigate N2O-N emissions from the maize and wheat crops. Hence, the use of NOCU and application of NI with urea could be a better option to mitigate N2O-N emissions from MWR of the upper IGP of India.

The experiment was conducted during 2018-19 and 2019-20 at ICAR-IARI research farm, to see the effect of crop establishment and nutrient management options on growth and yield of wheat under maize-wheat system. The experiment was laid out in split plot design with 03 replications, comprising conventional tillage without residue (CT-R), conventional tillage with 3 t/ha residue (CT+R), permanent raised bed without residue (PRB-R) and permanent raised bed with 3 t/ha residue (PRB+R) in main plot and nutrient management, viz. soil test-based(STB), Nutrient Expert® based (NE) and NE+ GreenSeekerTM based recommendations (NE+GS) in sub-plot. A significantly (P≤0.05) higher crop growth, viz. plant height, dry matter accumulation and leaf area index under PRB+R compared to other crop establishment technique. Differentyield parameters (yield, grain straw ratio and harvest index) and yield attributes of wheat grown under PRB+R were significantly higher (P≤0.05) over other crop establishment technique. A significantly (P≤0.05) higher crop growth, yield attributes, grain yield (5.01 and 5.05 t/ha), grain: straw ratio (0.65 and 0.65) and harvest index (39.31 and 39.36) of wheat were recorded with NE+GS based fertilization during 2018-19 and 2019- 20, respectively. Pearson correlation matrix analyzed for different growth and yield parameters showed a significant positive correlation (r) among themselves. Study infer that growing of wheat on the permanent raised bed along with 03 t/ha residue retention on surface and precision nutrient prescription using NE and GreenSeekerTM optical sensor showed promise for sustainable high productivity in intensively cultivated Trans-Gangetic Plains.

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. (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.

A study was undertaken to evaluate the long term effect of different conservation agriculture (CA) practices on infiltration characteristics of soil and empirical Kostiakov model and physical process based Green and Ampt, and Philip models were used to predict infiltration rates. The performance of different models was evaluated using statistical criteria. Six treatments were selected, viz. conventional tillage (CT), permanent narrow bed (PNB), permanent narrow bed with residue (PNB+R), permanent broad bed (PBB), permanent broad bed with residue (PBB+R) and zero tillage (ZT). Results showed that the initial infiltration rate was highest (22.93 cm hr-1) in PBB+R and was lowest (7.64 cm hr-1) in CT. Cumulative infiltration of all the treatments followed the order: PBB+R>PNB+R>PBB>PNB>ZT>CT. The ‘a’ values of Kostiakov model was 197.5 and 310 % higher in PBB and PBB+R as compared to CT. Steady state infiltration (ic) of Green and Ampt model was found to be highest (8.47 cm hr-1) in PBB+R and was lowest (1.88 cm hr-1) in CT. Sorptivity (S) parameter (cm hr-0.5) of the Phillip model was found to be highest in PNB+R (67.33) followed by PBB+R (43.61) and lowest in CT (16.23). Highest saturated hydraulic conductivity (‘K’) value of Phillip model was obtained in PBB+R followed by PBB> PNB>PNB+R>CT. After checking the model performance, it has been found that simple empirical Kostiakov (1932) infiltration model represented the infiltration rate and time relationship in a better way and characterized the best fit with the experimentally observed field infiltration data.

Wilt caused by Fusarium oxysporum, sp. Ciceris (FOC) is an important disease causing losses up to 10% in chickpea yield. Experiments were conducted growing chickpea in free air ozone and carbon dioxide enrichment rings under four treatments of elevated ozone (O3) (EO:60 ± 10 ppb), elevated carbon dioxide (CO2) (ECO2:550 ± 25 ppm), combination of elevated CO2 and O3 (EO + ECO2) and ambient control for quantifying the effect on growth, yield, biochemical and nutrient content of chickpea. For studying the impact on wilt disease, chickpea was grown additionally in pots with soil containing FOC in these rings. The incidence of Fusarium wilt reduced significantly (p < 0.01) under EO as compared to ambient and ECO2. The activities of pathogenesis-related proteins chitinase and β-1,3- glucanase, involved in plant defense mechanism were enhanced under EO. The aboveground biomass and pod weight declined by 18.7 and 15.8% respectively in uninnoculated soils under EO, whereas, in FOC inoculated soil (diseased plants), the decline under EO was much less at 8.6 and 9.9% as compared to the ambient. Under EO, the activity of super oxide dismutase increased significantly (p < 0.5, 40%) as compared to catalase (12.5%) and peroxidase (17.5%) without any significant increase under EO + ECO2. The proline accumulation was significantly (p < 0.01) higher in EO as compared to EO + ECO2, and ECO2. The seed yield declined under EO due to significant reduction (p < 0.01) in the number of unproductive pods and seed weight. No change in the protein, total soluble sugars, calcium and phosphorus content was observed in any of the treatments, however, a significant decrease in potassium (K) content was observed under EO + ECO2. Elevated CO2 (554ppm) countered the impacts of 21.1 and 14.4 ppm h (AOT 40) O3 exposure on the seed yield and nutrient content (except K) in the EO + CO2 treatment and reduced the severity of wilt disease in the two years' study.

For sustainable crop production and maintenance of soil health, conservation agriculture (CA) practices provides an opportunity for improving soil structure and physical health, nutrient and water use efficiency, soil organic carbon and mitigation of greenhouse gases emission from agriculture. CA is primarily based on four crop management practices such as minimum soil disturbance or no-tillage; permanent or semi-permanent retention of crop residue; crop rotation and control traffic. Different CA management practices affect crop yield as well as soil properties. CA makes necessary modifications in different soil hydro-physical properties, viz. increase in soil water infiltration, reduction in water runoff and soil loss, and reduction in evaporation loss. No tillage (NT), residue retention and crop rotation combined effect the soil organic carbon concentration. Different crop rotations and residue retentions and crops with different rooting depths used in CA practices have proved to reduce the compaction constraints.CA can help to mitigate GHG emissions, viz methane (CH4) and nitrous oxide (N2O) from agriculture by improving soil C sequestration, enhancing soil quality, nitrogen and water use efficiencies, and decreasing fuel consumption. But effect of CA and conventional agricultural practices of porosity and pore size distribution is very much limited. When CA is practiced for six to ten years there is improvement in soil structure, porosity and pore size distribution, macro-micro faunal activity, and organic matter content..The soil under ZT has the lowest porosity as compared to conventional management practices. The highest porosity and the maximum connected pores are frequently seen in conventionally tilled soil. In this paper, an attempt has been made to review the variation of porosity and pore size distribution and other soil physical properties under conservation agricultural practices.

Priming is used to increase vigor, germination synchronization, seedling growth, and field establishment by advancing metabolic processes within seeds. Seed respiration is a good indicator of the metabolic processes that lead to transition toward germination. Onion seeds (cv. Pusa Ridhi) subjected to osmopriming (−1.5 MPa PEG6000 for 7 days), magnetopriming (100 mT for 30 min) and halopriming (150 mM KNO3 for 6 days), were evaluated at different times of imbibition to study the emergence index and respiration indices such as infrared thermal fingerprint, CO2 evolution rate, cytochrome c oxidase activity, and soluble sugars profile. Haloprimed seeds exhibited 42.5% higher emergence index as compared to unprimed control. Primed and unprimed seeds showed negative values for relative temperature (ΔT) (difference in temperature of seed and its immediate environment). Haloprimed seeds had the lowest values (−4.1 to −2.3°C) compared to other priming treatments over the germination period. Soluble sugars like raffinose, sucrose, glucose, and fructose contents were monitored and it was observed that en masse raffinose, glucose, and fructose levels were (17.5–59.9%) lower in haloprimed seeds over control. A positive correlation (r2 = 0.504∗∗) was derived between the amount of these sugars and ΔT. Seed respiration, measured as CO2 evolution rate was more for haloprimed seeds that indicated that these soluble sugars were used as respiratory substrates. Significantly higher cytochrome c oxidase activity (40.7–89.8% and 12.5–66.6%) was observed in all primed seeds at 28 and 36 h, respectively. Among the various seed priming methods, halopriming proved to be the most effective priming treatment in onion seeds as evidenced by the higher respiration indices that resulted in faster metabolic rate and emergence index.

Global food security is challenged by increasing levels of CO2, O3 and temperature trough their impacts on production and grain quality of wheat, one of the major C3 crops and staple food across the world. The present study was conducted to assess the effects of elevated levels of CO2 (EC; 550 ppm) and tropospheric O3 (EO; 70 ppb) as well as of combined interactive treatment [EC X EO; ECO] on plant growth, yield and grain quality of two wheat cultivars (HD-2967 and C-306) grown during 2016–17 and 2017–18 using free air ozone and carbon dioxide enrichment (FAOCE) facility under field conditions. Individually, EC, increased leaf area index (LAI; 15.9–28.2%), photosynthetic rate (Pn; 11.4–20.3%) and yield (8.2–20.9%) whereas EO declined LAI (5.1–12.5%), Pn (2.8–11.8%) and yield (2.2–14.2%) over ambient conditions (Amb: 405.2 ppm CO2 and 30.7 ppb O3). Under ECO condition, EC increased LAI (2.2–17.1%), Pn (2.8–17.6%) and grain yield parameters (4.4–24.3%) across the cultivars in both years, but reduced the positive effects of EO on quality as compared to Amb. Dilution effect of increased yield under EC condition have reduced total protein, micro- and macro-nutrient concentrations whereas EO increased them notably compared to Amb. Starch in grains increased under EC but reduced under EO as compared to Amb. AOT40, the sum of averaged difference of O3 h−1 concentration beyond 40 ppb for 7 hours (31233 ppb h−1) in FAOCEs rings during the crop growth period led to reduction in average grain yield of HD-2967 and C-306 by 11.6 and 8.5% or by 1.6 and 1.3% yield loss per ppb increase of O3, respectively. The growth, yield and quality parameters of both wheat cultivars responded similarly but to different extent to all treatments. EC was able to offset the negative effects of EO on yield and yield components only, but not those concerning the quality of grains. To stabilize global food security, precursor gases forming tropospheric ozone must be constrained.

Rice growing under anaerobic conditions followed by spring wheat under an aerobic environment differentially impact the net ecosystem exchange (NEE) of carbon dioxide (CO2) in rice-wheat systems of the north-western Indo-Gangetic Plains (IGP). This is the first estimation of the NEE in a rice-spring wheat sequence via the eddy covariance technique in the north-western Indo-Gangetic Plains, which was partitioned into gross primary productivity (GPP) and ecosystem respiration (RE) and correlated with the environmental variables. Higher CO2 uptake of −10.43 g C m−2 d−1 was observed in wheat during heading as compared to −7.12 g C m−2 d−1 in rice. The net uptake of CO2 was 25% lower in rice. The average daily NEE over the crop season was −3.74 and −5.01 g C m−2 d−1 in rice and wheat, respectively. The RE varied from 0.07–9.00 g C m−2 d−1 in rice and from 0.05–7.09 g C m−2 d−1 in wheat. The RE was positively correlated with soil temperature at 5 cm depth (0.543, p < 0.01) in rice and with air temperature (0.294, p < 0.01) in wheat. The GPP was positively correlated with air temperature (0.129, p < 0.05) and negatively correlated with vapor pressure deficit (VPD) (−0.315, p < 0.01) in rice. In wheat, GPP was positively correlated with air temperature (0.444, p < 0.01) and soil moisture (0.471, p < 0.01). The rate of GPP over the crop duration was nearly the same in both rice and wheat, however, the RE was higher in rice as compared to wheat, thus, the ratio of cumulative RE/GPP was 0.51 in rice and much lower at 0.34 in spring wheat. Rice contributed 46% and 43% to the annual totals of RE and GPP, respectively, while spring wheat contributed 36% and 51%. The NEE of CO2 was higher in spring wheat at −576 g C m−2 d−1 as compared to −368 g C m−2 in rice. Thus, while estimating the carbon sink potential in the intensively cultivated northern IGP, we need to consider that spring wheat may be a moderately stronger sink of CO2 as compared to rice in the rice-wheat system.

BACKGROUND: Conjunctival sutures used in pterygium surgery are not only time-consuming process but also may lead to local complications such as discomfort, scarring, granuloma, or infection. Plasma-derived products such as fibrin glue may produce possible hypersensitivity reactions whereas the risk of viral transmission remains theoretically possible. We describe a simple method of achieving conjunctival autograft adherence during pterygium surgery avoiding potential complications associated with the use of fibrin glue or sutures. MATERIALS AND METHODS: After pterygium excision and fashioning of the autologous conjunctival graft, the recipient bed is encouraged to achieve natural hemostasis and relative desiccation before graft placement. Excessive hemorrhage in the graft bed is tamponed. Graft adherence and positioning is examined 12–15 min after surgery. RESULTS: A total of 205 cases of pterygium underwent excision with conjunctival autograft without using sutures or glue. Mean follow-up time was 14.6 months. Cosmesis achieved was excellent in all cases. There were no intraoperative complications seen. Recurrence was seen in 6.8% of cases (14 cases). Nasal gaping was seen in 36% of cases (74 cases), which healed spontaneously without any surgical intervention. CONCLUSION: This simple technique for pterygium surgery is not only cost effective and quick but also may prevent potential adverse reactions encountered with the use of foreign materials and in this large series provided safe and comparable results to current methods.

Weeds and nutrients, particularly N, are two crucial aspects of conservation agriculture (CA), whose management often poses challenge. The combined effects of weed and N management have hardly been studied under CA. This experiment was undertaken to evaluate their effects on weed suppression, soil properties and productivity in a maize (Zea mays L.) – wheat (Triticum aestivum L. emend Fiori & Paol) system under conservation agriculture during 2013-14 and 2014-15. Three weed control treatments as main plots and four nitrogen levels as sub-plots treatments were based on integrated weed management, soil test and plant sensor–GreenSeeker (GS)-aided approach. It was observed that the herbicide combination (atrazine + pendimethalin) and the brown manuring + 2,4-D weed management in maize resulted in 66% and 31% weed control index, respectively over weedy check. But, in wheat, clodinafop-propargyl + carfentrazone-ethyl (post-emergent) and pendimethalin + carfentrazone (pre-emergent) resulted in 81% and 58% weed control index, respectively. The mean maize grain and stover yields were increased by 12% and 8%, respectively due to the optimised GS–N treatments (N2, N3, and N4) than entire N basal application (N1). Also, mean wheat grain and straw yields increased by 9% and 8%, respectively over whole N basal application. The ‘best optimised’ GS–N (N2– 50% basal + 25% broadcast at 25 DAS + rest N guided by GS) had 6%, 7% and 15% greater mean weight diameter, saturated hydraulic conductivity and microbial biomass carbon over whole N basal application after two years of cropping. While brown manuring (maize) + herbicide combination (wheat) had 4%, 7% and 6% greater mean weight diameter, saturated hydraulic conductivity and microbial biomass carbon, respectively over herbicide combinations alone. Available N, P, and K in soil were 8%, 11% and 2% higher in the optimised GS–N treatments over entire N applied as basal. It may be concluded that the integration of brown manuring (in maize)+ herbicide combinations (in wheat), and the optimisation and synchronisation of N fertilisation can suppress weeds, enhance soil fertility with improved maize and wheat productivity.

A field experiment was conducted in a split plot design at the research farm of ICAR-Indian Agricultural Research Institute (IARI), New Delhi during summer and kharif seasons of 2015 and 2016 to study the influence of in-situ and ex-situ green manuring and zinc fertilization on nutrient uptake, yield attributes, correlation between yield and yield attributes, and yield of Basmati rice (Oryza sativa L.). Results of this study revealed that the incorporation of Sesbania aculeata green manure @ 33.8 and 35.6 t/ha prior to transplanting of Basmati rice during 2015 and 2016, respectively resulted in higher yield attributes and yield of Basmati rice compared with Vigna umbellata, Leucaena leucocephala and summer fallow during both the years. Foliar application of 0.5% solution of chelated Zn-EDTA at 20, 40, 60 and 80 days after transplanting (DAT) was better than soil application of Zn with regard to yield attributes and yield of Basmati rice and uptake of nutrients by the crop. In general, there was significant and positive correlation of grain yield with yield attributes. The uptake of nutrients by the crop was highest with incorporation of Sesbania aculeata and lowest in summer fallow.

Global climate change has a major impact on growth and sustainability of agro-ecosystem. Keeping in view the importance of rising O3 and CO2 concentration in atmosphere, a field experiment was conducted on chickpea (variety: Pusa 5023) in the experimental farm in Free Air Ozone and Carbon dioxide Enrichment (FAOCE) facility at ICAR-Indian Agricultural Research Institute (IARI), New Delhi under four ozone and carbon dioxide treatments (ECO: elevated CO 2 (550±10 ppm) +elevated O3 (70 ±10 ppb); EC: elevated CO 2 (550±10 ppm ppm) + ambient O3 (30±10 ppb); EO: elevated O3 (70±10 ppb)+ ambient CO 2 (400±10 ppm) and AMB; ambient CO 2 (400±10 ppm)+ ambient O3 (30± 10 ppb) during rabi season of 2016-17. The results revealed that the plant height, above ground biomass, CGR and RGR and seed yield of chickpea was significantly highest in elevated CO2 (EC) treatment followed by ECO treatment and lowest in elevated O3 (EO) treatment. Elevated ozone had negative impact whereas elevated carbon dioxide had positive impact on growth, biomass and WUE of chickpea and when both are combined the negative impact of elevated ozone were counteracted by elevated carbon dioxide.