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This article presents a closed-form analysis of CPW-fed slot dipole structures with the help of Schelkunoff’s biconical antenna analysis technique and Babinet’s principle. Input characteristics of CPW-fed slot dipole antennas are investigated, and closed-form expressions are derived for the purpose. The feed-gap inherently generated in CPW-fed antenna configurations is accounted for in the expressions, and the analysis of Schelkunoff is modified to address the same. Single-polarized structures can be orthogonally placed to generate dual-polarized characteristics – this notion is utilized to extend the proposed structure of a single CPW-fed slot dipole radiator towards a dual-polarized configuration. The proposed theoretical expressions are further validated for the dual-polarized geometry, and good agreement is observed in concerned theoretical and measured results. The simplicity of the proposed expressions is evident as they entirely consist of Sine and Cosine integrals and facilitate faster computation. Schelkunoff’s Biconical Antenna method is rarely used for solving a planar slot radiator problem which justifies the novelty of this article. The present work also, for the first time – modifies the method of Schelkunoff to further account for the inherently generated feed-gap in CPW-fed planar monopole or dipole configurations.

CPW-fed zigzag monopole radiators can be used to excite wide slots etched on the CPW-grounds for gain enhancement purposes, without significantly altering its resonance. The circuit analysis for CPW-fed zigzag monopole acting as a feed to a wide square slot is presented. Later, the uniform zigzag feed is tapered to support a gradual propagation constant modification. In both cases, the zigzag feed is conceived as an array of two constituent monopoles fed from the same source with modified propagation constants. Simulations along with the measured results are provided to validate the theoretical work which showed less than 2% error achieved in the predictions. Measured gains of the radiators are reported at their resonance frequencies, 2.93dB and 3.19dB respectively for the uniform and tapered zigzag feeds, which validates the observation of gain enhancement in this article.

Novel closed form expressions to investigate CPW-fed miniaturized planar monopole antennas are presented. The analysis of a CPW-fed strip monopole structure is further extended to derive expressions for the input impedances of miniaturized strip-monopoles supporting slow wave propagation. The concept includes the modification of the propagation constants of the structures and the modeling of them into their equivalent straight rectangular strip-monopoles on planar substrates. The meandered/miniaturized strip-monopole radiators are disintegrated to model them as the superposition of simpler structures and circuit theoretic analyses are performed. The correctness of the reported expressions is validated against the simulations as well as the experimental measurements. Such closed-form analysis facilitates simpler design procedures against other available techniques such as conformal mapping and full wave analysis. The circuit theoretic approach reduces the computational requirements as against the available commercial EM solvers and provides a suitable interface platform for system analysis.

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.

The dark and bright solitons in different systems are already known. If the intrinsic field is only considered, then the modal dynamics for small oscillations could be characterized by the bound state in a limited range of frequency, revealed via associated Legendre polynomial. The pairing and interplay between the dark and bright solitons occur. The disappearance of the bound state after a critical frequency gives rise to dark solitons in the unbound states that propagate through the domains. Above the upper boundary of the bound states, the estimated frequencies of dark solitons match with those experimentally found for ‘acoustical memory’.

The investigation of structural phase transition and anharmonic behavior of Yb2O3 has been carried out by high-pressure and temperature dependent Raman scattering studies respectively. In situ Raman studies under high pressure were carried out in a diamond anvil cell at room temperature which indicate a structural transition from cubic to hexagonal phase at and above 20.6 GPa. In the decompression cycle, Yb2O3 retained its high pressure phase. We have observed a Stark line in the Raman spectra at 337.5 cm−1 which arises from the electronic transition between 2F5/2 and 2F7/2 multiplates of Yb3+ (4f13) levels. These were followed by temperature dependent Raman studies in the range of 80–440 K, which show an unusual mode hardening with increasing temperature. The hardening of the most dominant mode (Tg + Ag) was analyzed in light of the theory of anharmonic phonon-phonon interaction and thermal expansion of the lattice. Using the mode Grüneisen parameter obtained from high pressure Raman measurements; we have calculated total anharmonicity of the Tg + Ag mode from the temperature dependent Raman data.

Since the discovery of colossal dielectric constant in CCTO supercapacitor in 2000, development of its practical application to energy storage has been of great interest. In spite of intensive efforts, there has been thus far, no report of proven application. The object of this research is to understand the reason for this lack of success and to find ways to overcome this limitation. Reported herein is the synthesis of our research in ceramic processing of this material and its characterization, particularly with the objective of identifying potential applications. Experimental results have shown that CCTO's permittivity and loss tangent, the two most essential dielectric parameters of fundamental importance for the efficiency of a capacitor device, are intrinsically coupled. They increase or decrease in tandem. Therefore, efforts to simultaneously retain the high permittivity while minimizing the loss tangent of CCTO might not succeed unless an entirely non-typical approach is taken for processing this material. Based on the experimental results and their analysis, it has been identified that it is possible to produce CCTO bulk ceramics with conventional processes having properties that can be exploited for fabricating an efficient energy storage device (EDS). We have additionally identified that CCTO can be used for the development of efficient solid state capacitors of Class II type comparable to the widely used barium titanate (BT) capacitors. Based on high temperature studies of the resistivity and the Seebeck coefficient it is found that CCTO is a wide bandgap n-type semiconductor material which could be used for high temperature electronics. The temperature dependence of the linear thermal expansion of CCTO shows the presence of possible phase changes at 220 and 770 °C the origin of which remains unexplained.

Inefficient management of irrigation and fertilizers emerges as the primary hurdle constraining the crop performance, profitability of broccoli (Brassica oleracea L. var. italica) production, resource wastage and environmental harm. To address this issue, a field experiment was conducted during winter (rabi) seasons of 2020–21 and 2021–22 at the research farm of ICAR-Indian Agricultural Research Institute, New Delhi. The research focused on investigating the effect of irrigation techniques and nitrogen management on broccoli yield, water use efficiency (WUE) and economic feasibility. The two main irrigation methods of drip irrigation and furrow irrigation as main factor, 2 irrigation regimes of full irrigation (100% ETC) and limited irrigation (75% ETC) as sub-factor, 3 nitrogen doses (N) of 125, 100 and 75% recommended dose of N as sub-sub factor were given and replicated thrice. The study aimed to analyse the yield, water use efficiency and assessment of economics under diverse irrigation water and N-management approaches. Under drip irrigation the mean yield and water-use efficiency shown substantial increase by 12 and 52% in comparison with furrow irrigated purple broccoli grown under the same condition. The highest benefit to cost (B:C) ratio of 3.81 and 4.79 was obtained in the treatment DRI1N1 during 2020–21 and 2021–22, respectively. Undoubtedly, the significance of adequate irrigation regime (100% ETC) and optimal N dose (125% RDN) became apparent, as they played significant roles in enhancing crop performance and ensuring the attainment of maximum broccoli yield, WUE and economics in Trans-Gangetic Plains region.

A two-year field study was carried out during winter (rabi) seasons of 2020–21 and 2021–22 at the research farm of ICAR-Indian Agricultural Research Institute, New Delhi with the aim of examining the impacts of various methods of tillage, residue management and nitrogen (N) application on wheat (Triticum aestivum L.) yield, water use efficiency (WUE), and nitrogen use efficiency in terms of Partial Factor Productivity of Nitrogen (PFPN). The study utilized a split-split plot design with 3 replications, where the main plot consisted of two tillage systems [conventional tillage (CT) and no tillage (NT)], the subplot comprised 2 residue levels [maize residue @5 t/ ha (R+) and no residue (R0)], and the sub-sub plot involved 3 N levels [60, 120, and 180 kg N/ha, representing 50% (N60 kg N/ha), 100% (N120 kg N/ha), and 150% (N180 kg N/ha)] respectively. The results indicated that both tillage and residue management considerably influenced the grain and biomass yield of wheat. Over the two years, NT exhibited a 7% higher WUE compared to CT, but the change was insignificant. However, in years with lower rainfall, crop residue mulching had a significant positive impact on WUE, while in years with higher rainfall; its effect on WUE was insignificant. Moreover, tillage practices had a considerable effect on the PFPN. In the year 2020–21, PFPN under NT was 3.59% higher than under CT, and in the year 2021–22, it was 2.06% higher. Furthermore, with an increase in N levels, WUE showed a substantial increase, while PFPN decreased.

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.

Introduction: Odontogenic cystic lesions requiring conservative management were treated with a novel technique of modified decompression and assessed. Aims and Objective: This study aimed to evaluate the resolution of the lesion, recurrence, and complications in patients treated with the novel modified decompression technique. Materials and Methods: The retrospective study included patients treated with the novel modified decompression technique between 2004 and 2022. The cystic lesions were packed with chlorhexidine acetate gauze dressing (Bactigras), and patients were prescribed a combination of Calcium, Vitamin C, and Vitamin D. Pack was changed periodically until a reduction of at least 80% in the volume of the lesion was achieved. Period of decompression, volume at each follow-up, and lesion size were recorded. In addition, inter-group significance co-relating the size and diagnosis of the lesions with the rate and duration of healing were derived by ANOVA test. Results: OKC, unicystic ameloblastoma, and dentigerous cysts were included, and the follow-up period ranged from one year to eighteen years. 25 cases (83.33%) showed full resolution, whereas five cases (16.17%) showed more than 80% resolution. The period of decompression and the rate of decompression was found to correlate with both the diagnosis and the size of the lesion. Conclusions: The modified decompression technique is superior to traditional decompression with a high rate of resolution of cystic lesions and no recurrence over a long follow-up period.

Long-term (13 years) impact of organic and conventional farming on soil physical properties was evaluated under a rice (Oryza sativa L.) – wheat (Triticum aestivum L.) cropping system in a sandy clay loam soil at New Delhi. The treatments included unfertilized control (T1), conventionally managed (T2) and five organic treatments (T3: FYM @ 10 t/ha to rice and wheat, T4: SGM for rice and LGLM for wheat, T5: SGM + BGA for rice and LGLM + Azotobacter for wheat, T6: SGM + FYM for rice and LGLM + FYM for wheat, and T7: SGM + FYM + BGA for rice and LGLM + FYM + Azotobacter for wheat). The application of organic amendments had positive influence on soil physical properties such as saturated hydraulic conductivity (Ks), field capacity (FC) and permanent wilting point (PWP), plant-available water capacity (PAWC), water holding capacity (WHC), distribution of aggregate size fractions, bulk density (Db), and porosity in the 0-15 and 15-30 cm soil layer. A favourable effect of organic amendments was also found on soil strength (at depth 0-70 cm). Even, values related to these properties were significantly affected by the kinds of organic amendments. But, T1 and T2 had no improvement in soil physical properties over the organic ones. Value of Ks decreased with increase in soil depths. T7 and T3 were superior in Ks to other treatments for 0-15 and 15-30 cm soil depths. Volumetric moisture content at FC (θFC) and PWP (θWP) increased with addition of organic amendments and got varying response due to the kinds of organic amendments or their combinations. θFC and θWP were decreased substantially under T1 and T2, because of no addition of organic inputs. As a result of θFC and θWP, PAWC had also signified an improvement under the influence of different organic amendments over T1 and T2. Generally (for both depths), PAWC of T3, T6 and T7 were 17-26% more than T1, T2, T4 and T5. WHC of upper soil layer (0-15 cm) was greater for organic amended plots than plots devoid of organic inputs and lower values were recorded for 15-30 cm soil layer. WHC of T3, T7 and T6 was highest in comparison to plots amended only with (without FYM) green manure, BGA or Azotobacter as well as T1 and T2 for both depths (0-15 and 15-30 cm). A better soil aggregation was observed under organic amended plots for large and small macro-aggregates (LM - >2 and SM-0.25-2 mm) in both soil depths. Lowest value of Db with highest percentage of pore space was noted under T7 than other treatments in both soil layers. Soil strength was significantly lower in organic amended plots than T1 and T2. This study clearly indicated that application of organic inputs especially FYM, improved the soil physical properties, which resulted in better soil aggregation, porosity and soil moisture retention.

Field experiments were conducted during 2015–16 and 2016–17 on wheat (cv HD2967) in a sandy loam soil at ICAR-Indian Agricultural Research Institute, New Delhi to study the effect of tillage and irrigation management on radiation use efficiency (RUE) of wheat. The treatments comprising of three levels of tillage as main plot factor (Conventional tillage, Deep tillage and No tillage) and three levels of irrigation as subplot factor (I1: 1 irrigation, I3: 3 Irrigations and I5: 5 Irrigations) were evaluated in a split plot design. The results showed that there was no significant difference among tillage treatments with respect to extinction coefficient. However, pooled data of 2 years, extinction coefficient due to I5 was significantly higher than that of I3 and I1 by 8.8 and 23.8%, respectively, and extinction coefficient due to I3 was significantly higher than I1 by 13.8%. There was no significant difference among the tillage treatments with respect to radiation use efficiency (RUE) of wheat, but RUE increased significantly with increasing irrigation level. RUE of wheat under I5 was significantly higher than that of I1 and I3 treatments but there was no significance difference between I1 and I3 with respect to RUE of wheat in both the years.

A field experiment was conducted on Typic Ustochrept soil at the Crop Research Centre of Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut, for two years (2014–15 to 2015–16) to evaluate site specific nutrient management (SSNM) against state recommendation (SR), integration of SSNM and SR with crop residue and farm yard manure. In terms of crop growth yield, nutrient uptake and economics, SSNM had significantly higher growth parameters, viz. number of tillers/m2 and dry matter accumulation as compared to SR in both rice and wheat crops. Different yield attributes, viz. number of grains/panicle or spike, test weight of rice and wheat were also higher with SSNM. SSNM out yielded for rice, wheat and rice-wheat system (RWS) productivity by 10.3%, 14.1% and 11.9%. System N, P and K uptake under SSNM was also higher by 24.36, 9.55 and 36.01 kg/ha, respectively, compared to SR. An additional income of `12953/ha over SR and maximum return/rupee invested (`2.50) was also recorded with SSNM. Recycling of 5 t/ha rice and wheat straw residue along with SSNM had added advantage.

Obesity is characterized by a state of chronic, unresolved inflammation in insulin-targeted tissues. Obesity-induced inflammation causes accumulation of proinflammatory macrophages in adipose tissue and liver. Proinflammatory cytokines released from tissue macrophages inhibits insulin sensitivity. Obesity also leads to inflammation-induced endoplasmic reticulum (ER) stress and insulin resistance. In this scenario, based on the data (specifically patterns) generated by our in vivo experiments on both diet-induced obese (DIO) and normal chow diet (NCD) mice, we developed an in silico state space model to integrate ER stress and insulin signaling pathways. Computational results successfully followed the experimental results for both DIO and NCD conditions. Chromogranin A (CgA) peptide catestatin (CST: hCgA352-372) improves obesity-induced hepatic insulin resistance by reducing inflammation and inhibiting proinflammatory macrophage infiltration. We reasoned that the anti-inflammatory effects of CST would alleviate ER stress. CST decreased obesity-induced ER dilation in hepatocytes and macrophages. On application of Proportional-Integral-Derivative (PID) controllers on the in silico model, we checked whether the reduction of phosphorylated PERK resulting in attenuation of ER stress, resembling CST effect, could enhance insulin sensitivity. The simulation results clearly pointed out that CST not only decreased ER stress but also enhanced insulin sensitivity in mammalian cells. In vivo experiment validated the simulation results by depicting that CST caused decrease in phosphorylation of UPR signaling molecules and increased phosphorylation of insulin signaling molecules. Besides simulation results predicted that enhancement of AKT phosphorylation helps in both overcoming ER stress and achieving insulin sensitivity. These effects of CST were verified in hepatocyte culture model.

The present experiment was conducted to study the spatio-temporal variation of available nitrogen fraction in cotton (Gossypium hirsutum L.) in conservation agricultural based long term experiment (since 2010) during 2019-20. The treatment comprises two distinct practices, i.e. conventional tillage (CT) and zero tillage (ZT). Under ZT, permanent narrow bed without (PNB) and with residue of previous crops (PNB+R); permanent broad bed without (PBB) and with residues (PBB+R); flat bed (FB) and FB with residues (FB+R). Soil samples were collected (0-15 and 15-30 cm) at pre-flowering, flowering, boll formation and harvest stages. Adoption of CA practices increased the NH4-N, NO3-N and mineral-N fractions of nitrogen at different crop growth stages. Highest NH4-N, NO3-N and mineral-N were recorded at flowering and boll formation stage respectively. The effect of crop residue retention and crop establishment methods on available N fractions was prominent up to 15 cm soil depth. Crop residue retained plots recorded significantly higher N fraction compared to respective without residue and CT plots. Residue retained plots of FB, PBB, PNB recorded 50, 25 and 36% higher NO3-N concentration as compared to respective without residues plots at pre-flowering stage. At flowering stage, maximum NH4-N was recorded in PBB+R (17.9 mg/kg) and FB+R plots (17.5 mg/kg), which was approximately 68 and 16% higher over CT and PNB+R plots. The results revealed that zero tillage together with PBB+R could be a viable option over conventional practice for maintaining nitrogen availability to plants under cotton-wheat (Triticum aestivum L.) cropping system in semiarid climate.

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.

Field experiment was conducted during rabi season for two years (2014-15 and 2015-16) on wheat cultivar HD- 2967 in a sandy loam soil (Inceptisol) for simulation of evapotranspiration, crop water use efficiency (WUE) and yield of wheat under different tillage (Conventional tillage (CT) and no tillage (NT)), residue (maize residue @ 5 t ha-1 (R+) and without residue (R0)) and nitrogen (60, 120 and 180 kg N ha-1, representing 50% (N60), 100% (N120) and 150% (N180) of the recommended dose of nitrogen for wheat (Triticum aestivum L.), respectively management practices using DSSAT (v 4.6) model. Experimental data of the years 2014-15 and 2015-16 was used for the calibration and validation of the model, respectively. The results showed no significant difference in grain and biomass yield due to tillage and crop residue mulch but it increased significantly with increase in the N levels. The WUE of wheat was also not influenced by tillage but increased significantly with the increase in N levels. The DSSAT model could satisfactorily simulate grain yield (R2 = 0.759), biomass yield (R2= 0.728) and seasonal ET (R2= 0.904) in wheat but simulation of WUE (R2= 0.414) was not significant under different tillage, residue and nitrogen management with acceptable level of accuracy.

A study was conducted on a semi-arid climate and sandy loam soils of Indian Agricultural Research Institute farm, New Delhi to evaluate the short-term (5 years) interactions of tillage, residue and nitrogen management on soil physical properties, root growth and yield of wheat (Triticum aestivum L.) in a maize-wheat cropping system in a split-split plot design comprising two tillage (No tillage and conventional tillage), two residue levels (no residue, maize residue @ 5 t ha-1) and three nitrogen doses (N60, N120 and N180) as the main plot, sub plot and sub subplot treatments, respectively. It was observed that bulk density (up to 45 cm), penetration resistance (10-27 cm depth) reduced under no tillage and residue applied plots while the porosity (15-60 cm), mean weight diameter (0-15 cm), organic carbon (0-15 cm) improved in these treatments. The hydraulic conductivity was significantly enhanced due to residue applications in the surface layers (0-15cm). Root growth parameters were improved under no tillage and crop residue mulching. Although neither tillage nor residue mulching could significantly influence the grain and biomass yield of wheat on two years of study (2017-18, 2018-19), yield increased significantly with increasing nitrogen doses. Thus no tillage, residue mulching with 150% recommended dose of nitrogen can be practised for maintaining a better soil physical health, root growth without any significant reduction in crop productivity compared to conventional tillage.

A pot experiment was conducted in acid soil (Alfisol) using four levels of lime (CaCO3) based on lime requirement (LR), viz. 0, 1/3, 2/3, and 1 and four levels of boron (B), viz. 0, 1.0, 1.5 and 2 mg/kg to evaluate the effect of applied calcium (Ca) and boron (B) on biomass yield, nutrient uptake of tomato (Solanum lycopersicum L.) and soil properties. The results indicated that application of Ca @ 2/3 LR and 1 LR significantly increased biomass yield of tomato by 21% and 16%, respectively over control. Boron application @ 1.0 mg/kg recorded highest biomass yield (19.6 g/pot) of tomato as compared to other boron treatments. Applied Ca @ 2/3 LR significantly increased the uptake of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulphur (S), zinc (Zn) and copper (Cu), whereas iron (Fe), manganese (Mn) and B uptake increased only up to Ca @ 1/3 LR treatment. Application of B increased the nutrients uptake over control, whereas it was observed significantly higher with B @ 1.5 mg/kg treatment. Applied Ca significantly enhanced the pH and available Ca in post-harvest soil, whereas salicylic acid extractable boron (SAE-B) was declined. The combined application of calcium @ 2/3 LR and B @ 1.5 mg/kg was most effective in enhancing the yield and nutrient uptake of tomato.

Short-term (5 years) effect of conservation agriculture (CA) practice on soil hydro-physical characteristics, soil organic carbon status and root morphology in wheat (triticum aestivum L.) was monitored under rice (Orgza sativa L.)-wheat rotation in a clay loam soil at the Indian Agricultural Research Institute, New Delhi. A small improvement in soil water content and a marginal decrease in bulk density by CA contributed in significant reduction (30-37%) in sub-surface compaction. The CA improved soil structure in the plough layer (0-15 cm) with significant increase in soil organic carbon status (27-38%). A marginal change in pore size distribution was recorded in favour of larger volume of retention pores (11-12%), in expense of macro- or drainable pore space. Steady-state infiltration, which was essentially profile-controlled, was therefore lower in the CA plots. Decrease in sub-surface soil strength and better soil water retention facilitated root growth in wheat in the sub-surface layer under CA. Results implied that the CA practice in rice-wheat system, although with a shorter period, led to an overall physical improvement of the most active root zone. This had positive impact on root morphology, which contributed to increase in the crop yield.

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.