Search

The study aimed at examining the effect of Iron (Fe) management strategies on the redistribution of Fe fractions in soil and on the Fe bioavailability and phytic acid (PA) content in lentil grains. A pot experiment was conducted in Completely Randomized Design with 8 treatments replicated thrice. The treatments were Control (no fertilizer); Recommended dose of fertilizers (RDF) i.e. 20:40 (N: P2O5); RDF + Fe (basal application @10 kg/ha); RDF + Fe (foliar@ 1% (w/v) solution); RDF + Fe (basal + foliar); RDF + FeSB (biopriming with Fe solubilizing bacteria (Enterobacter cloacae strain BAU3) @ 5 mL/kg seed (1 x109 cfu mL−1)); RDF + Fe (seed nutripriming with 1% (w/v) solution); and RDF + (biopriming + nutripriming). Fe source for the treatments was Fe-EDDHA chelate. Higher Fe release from these fractions was observed under biopriming + nutripriming with water soluble Fe of 21.09 and 20.82 mg kg−1, respectively for the biopriming + nutripriming and sole biopriming treatments; and organically bound Fe of 230.95 and 211.36 mg kg−1 for the same treatments. These fractions contributed toward higher Fe uptake which was highest under biopriming + nutripriming. Values were statistically significant for biopriming and nutripriming and basal + foliar treatment. Lowest PA values in lentil grains as well as PA/Fe ratio were estimated under basal + foliar and biopriming + nutripriming treatments. Combined basal and foliar application of Fe esp. in chelated form and use of seed priming strategies have immense potential in enhancing the Fe bioavailability in grains from soil, seed or foliage. [ABSTRACT FROM AUTHOR]

Crop establishment methods play a vital role in the predominance of nutrient forms. Nitrogen dynamics in the soil can alter micronutrient availability and uptake. Four treatments each replicated thrice, comprising of three methods of rice establishment viz., puddled transplanted rice (PTR), unpuddled transplanted (UPTR), and direct seeded rice (DSR) in different combinations of rotation with conventionally tilled lentil (CTL) and zero till lentil (ZTL) were compared for their effect on inorganic nitrogen in the soil and its consequent effect on the micronutrient availability in soil and their uptake by rice grain. As per the results obtained from the study, the different establishment techniques with associated treatments after 7 years of continuous cultivation did not have any significant effect on general soil properties like pH, electrical conductivity (EC), organic carbon (OC), and cation exchange capacity (CEC). Treatments had a significant effect on soil nitrogen content and uptake and on soil micronutrient status and their uptake by rice as estimated after harvest of the rice crop. UPTR-ZTL crop rotation with crop residue management and biopriming with Azotobacter was found to be the most efficient management practice and performed better than the conventional crop establishment techniques like PTR and CTL systems. Nitrogen content in soil and plant N uptake showed positive correlations with micronutrient uptake by the rice grain. Significant positive correlations were obtained with the uptake of Fe, Mn, and Zn. Nitrogen dynamics (irrespective of crop establishment methods) in soil especially ammoniacal N, had a positive effect on the cationic micronutrient uptake by the crop, but results were not conclusive enough to suggest the role of N forms on uptake and translocation of micronutrient cations. [ABSTRACT FROM AUTHOR]

In this study, a density functional theory (DFT) method was utilised to predict the reaction mechanism of N-heterocyclic carbene (NHC)-catalysed remote N–H activation in indole aldehydes for the synthesis of enantiomerically enriched oxazinoindole derivatives. Simulation results indicate that the mechanism involves six energetically feasible stages: (a) chemo-selective nucleophilic addition of NHC to indole aldehydes, (b) N,N-diisopropylethylamine (DIEA) and protonated DIEA-assisted simultaneous proton shifts for the generation of Breslow intermediates, (c) oxidation of Breslow intermediates, (d) another DIEA-assisted intermolecular proton shift for the formation of reactive aza-o-quinone methide (aza-o-QM) analogues, (e) stereo-selective [4+2]-cycloaddition of aza-o-QM to a ketonic moiety, and (f) regeneration of NHC with simultaneous formation of the desired product. Chemo- and stereo-selectivity of the titled reaction was analysed by adopting several well-known DFT tools. Conceptual DFT-derived reactivity indices and the frontier molecular orbitals (FMOs) were analysed comprehensively to unravel the real role of NHC in this proposed catalytic cycle. Besides NHC, DIEA and DIEA–H+ were found to play crucial roles in lowering the activation energy barrier of different proton transfer stages. This investigation may help in the rational designing of other NHC-catalysed novel organic transformations. [ABSTRACT FROM AUTHOR]

Bis(amino)cyclopropenylidenes (BACs) are the newly discovered umpolung catalysts with potential applications in the synthesis of numerous important organic moieties. A plausible mechanism for bis(diethylamino)cyclopropenylidene (Et‐BAC) catalysed synthesis of 1,4‐diketones has been investigated using density functional theory (DFT). The proposed catalytic cycle initiates with the nucleophilic interaction of in situ generated Et‐BAC with p‐methoxybenzaldehyde to form a zwitterionic intermediate, which on proton transfer reaction gives Breslow intermediate. Breslow intermediate then favours 1,4‐umpolung addition reaction with chalcone followed by another proton transfer to regenerate the Et‐BAC along with enolic form of the product. Enolic form ultimately transforms into the desired keto form, 1‐(4‐methoxyphenyl)‐2,4‐diphenylbutane‐1,4‐dione via protonated and free DBU aided proton shift mechanism. DFT‐derived reactivity parameters along with frontier molecular orbital (FMO) analysis have been successfully utilised to reveal the umpolung efficacy of Et‐BAC. This DFT exploration is in good accordance with experimental findings and also offers a deeper insight into the Et‐BAC catalysed organic transformations. [ABSTRACT FROM AUTHOR]

The binding of drugs to plasma proteins determines its fate within the physiological system, hence profound understanding of its interaction within the bloodstream is important to understand its pharmacodynamics and pharmacokinetics and thereby its therapeutic potential. In this regard, our work delineates the mechanism of interaction of Selumetinib (SEL), a potent anti‐cancer drug showing excellent effect against multiple solid tumors, with plasma protein bovine serum albumin (BSA), using methods such as absorption, steady‐state fluorescence, time‐resolved, fluorescence resonance energy transfer, Fourier transform infrared spectra (FTIR), circular dichroism (CD), synchronous and 3D‐fluorescence, salt fluorescence, molecular docking and molecular dynamic simulations. The BSA fluorescence intensity was quenched with increasing concentration of SEL which indicates interactions of SEL with BSA. Stern–Volmer quenching analysis and lifetime studies indicate the involvement of dynamic quenching. However, some contributions from the static quenching mechanism could not be ruled out unambiguously. The association constant was found to be 5.34 × 105 M−1 and it has a single binding site. The Förster distance (r) indicated probable energy transmission between the BSA and SEL. The positive entropy changes and enthalpy change indicate that the main interacting forces are hydrophobic forces, also evidenced by the results of molecular modeling studies. Conformation change in protein framework was revealed from FTIR, synchronous and 3D fluorescence and CD studies. Competitive binding experiments as well as docking studies suggest that SEL attaches itself to site I (subdomain IIA) of BSA where warfarin binds. Molecular dynamic simulations indicate the stability of the SEL–BSA complex. The association energy between BSA and SEL is affected in the presence of different metals differently. [ABSTRACT FROM AUTHOR]

Detailed hydrolysis mechanism of osmium(III) anticancer drug, (ImH)[trans-OsCl4(DMSO)(Im)] (Os-NAMI-A; Im = imidazole, DMSO = dimethyl sulfoxide) has been investigated using density functional theory (DFT) in combination with CPCM solvation model. In the first hydrolysis step, faster aquation is observed in the case of DMSO hydrolysis from Os-NAMI-A in comparison to the chloro ligand having activation Gibbs free energy (ΔGaq) value of 24.66 kcal mol−1, which is in good agreement with the experimental results. On the other hand, the second hydrolysis is mainly performed via the first chloro ligand hydrolysed Os-NAMI-A to form cis-[OsCl2(H2O)2(DMSO)(Im)]+ (P-2B). However, the hydrolysis of cis-diaquated Os-NAMI-A [OsCl3(H2O)2(Im)] (P-2A) shows enhanced feasibility in the third hydrolysis step with the lowest activation Gibbs free energy (17.27 kcal mol−1) and the rate constant value is computed to be 1.34 s−1. Additionally, it is observed that hydrogen bonding plays an important role in stabilizing the intermediates and transition states. Furthermore, calculated net atomic charges based on natural population analysis show charge redistribution during hydrolysis reactions. [ABSTRACT FROM AUTHOR]

Zinc (Zn) is an essential micronutrient that is found in almost all classes of enzymes. Its deficiency is a well-documented problem among cereal crops that causes decreased crop yields and nutritional quality. Therefore, an experiment was implemented in a randomized block design which included the treatments of bacterial inoculation consisting of T1 (Control), T2 (100% RDF;100:40:20), T3(100% RDF + 25 kg ZnSO4.7 H2O), T4(100%RDF+ ZnSB1– Bacillus sp. strain BAU_A2 @750 ml ha−1), T5 (100%RDF+ ZnSB2– Priestia megaterium strain BAU_A3 @750 ml ha−1), T6 (100%RDF+ ZnSB3-Bacillus subtilis strain BAU_A5@750 ml ha−1). The mineral NPK was applied as per treatments. The results indicated the maximum values of water soluble exchangeable Zn and organically bounded Zn in treatments consisting ZnSB1, ZnSB2 and ZnSB3, respectively. The WS+EXCH-Zn was significantly increased by 68.57%, 28.26%, 18%, 98.14%, 41.30%, 30.00% and 128.12%, 55.55%, 37.25%, 43%, 62.22% and 43.13% in first year (2018–19) and second year (2019–2020) under the soil treated with ZnSB1-Peribacillus simplex strain BAU_A1, ZnSB2-Bacillus sp. strain BAU__A2 and ZnSB3-Bacillus subtilis strain BAU_A5 along with 100%RDF over control, application of recommended dose of fertilizer with and without application of 25 kg ZnSO4 ha−1, respectively. However, the maximum decrement in Mn-oxide-bounded zinc (1.12 mg kg−1 soil) was observed with T6 which was significantly higher by 158%, 194.4%, 185.71% over control, 100% RDF with and without application of 25 kg ZnSO4 ha−1, which showed the solubilization of zinc with the activity of ZnSB in soil. The study may be beneficial to mitigate the zinc deficiency in soil and malnutrition in children. [ABSTRACT FROM AUTHOR]

A pot experiment was carried out in 2010 during wet season (July to December) at the Institute of Agricultural Sciences, Banaras Hindu University to evaluate the extent of root infection by AM (Arbuscular Mycorrhiza) fungi and yield attributing characteristics of cotton under both Bt (Bacillus thuringiensis) and non-Bt systems under varied soil types. It included three different soil orders i.e. Entisol, Inceptisol and Alfisol. Bt cotton (cv. NCS-138) and its non-transgenic isoline (cv. NCS-138) were grown until maturity. From the results it was evident that among the three different soils, red soil exhibited higher root infection in comparison to alluvial and black soil. Per cent root infection decreased significantly to the extent of 10-13% in Bt crop as compared to non-Bt counterpart and 9.5-15% during the three growth stages. During the intermediate stages of crop growth, there were significant differences in growth parameters and yield attributes between Bt and the non-Bt isoline. It was also observed that the alluvial soil produced higher shoot biomass compared to black and red soil during initial stages of crop growth. But during the intermediate stages of crop cycle, the growth picked up in black soil. In the final stage, alluvial soil produced higher biomass as compared to the black and red soil. At the same time, Bt-cotton plants showed comparatively more root length than non-Bt crop over the entire crop growth stages. [ABSTRACT FROM AUTHOR]

Background: Inflammation plays an important role in development and progression of the COVID 19 disease. Among all inflammatory markers, IL6 is a good predictor for symptomatic cases. But it is time-consuming, less cost-effective that cannot be done in low resource constraint setting. So, we want to search another equally effective inflammatory biomarker that can be done in low resource setting. NLR and d-NLR are inflammatory parameters, we estimate association of NLR and d-NLR with disease severity and mortality. Methods: 150 COVID-19 patients aging between 18 and 45 years and 150 age and sex matched apparently healthy people were included. Then case group participants are subdivided into three sub-groups according to disease severity. Thereafter, all of the patients and healthy persons were subjected to the estimation of serum IL-6 and find out NLR and d-NLR. Results: It was found that the mean NLR d-NLR and IL6 were increased with disease severity. Then Pairwise multiple comparison in the post hoc ANOVA analysis with Bonferroni correction within the case group was performed and it became evident that IL6 concentration and NLR were significantly increased. It also found that IL6 and NLR were well correlated with disease severity. Then Pearson correlation was done and it was shown that IL6 with NLR and d-NLR are well correlated with disease severity. Then to determine the diagnostic value of the NLR for COVID 19 ROC curve and logistic regression analysis were performed and found that NLR of 5.89 and d-NLR 2.78 were demonstrated as the optimal cut-off value as a predictor of disease severity and 9.48 was disease mortality. Conclusion: NLR and d-NLR equally effective like IL6 for disease severity, prognosis and mortality from COVID-19. They can be done in primary health care level as they are cheap, easily available. [ABSTRACT FROM AUTHOR]

Lower utilization efficiency of phosphorus (P) in soils is a major setback for the agricultural sector. The objective of this study was to investigate the effect of compost enriched with Rock phosphate on fractions of P in soil and how these forms affect the bioavailability of P in Rice. P fertilization was performed with the enriched compost and compared with rock phosphate and a conventional P fertilizer i.e. single superphosphate (SSP). We conducted a field experiment at Bihar Agricultural University, Sabour with Rice as the test crop in a randomized block design. Chemical P fractions were estimated through sequential fractionation and biomass production and P concentrations in plant parts were measured to estimate the plant P uptake. Yield, yield attributing parameters and P uptake in straw and grain were observed to be affected significantly by the addition of P enriched compost along with 50% recommended dose for P with the total recommended dose for N and K, when compared to absolute control. The alkaline nature of experimental soil seemingly improves the solubility of P from various fractions and the use efficiency of rice, which favors P uptake which was evidently the factors that contributed to these results. The percentage contributions of different fractions to the total P content in soil after paddy harvest were observed to be in the order: Labile-P < Fe/Al-P < Ca-P < residual P. Combined application of P enriched compost and inorganics sustained crop yield and enhanced P uptake in Rice when compared with sole application of chemical fertilizers. [ABSTRACT FROM AUTHOR]

We investigated the effects of Arbuscular Mycorrhiza (AM) fungi and various phosphorus (P) levels on the distribution and availability of P in dominant soils of Bihar, India. Potassium chloride (KCl)-P (labile P), sodium hydroxide (NaOH)-P (Fe-Al-bound P), hydrochloric acid (HCl)-P (Ca-bound P), and residual P (Res-P) fractions were analyzed in the soils under maize plant. Ca-bound P was the most abundant P fraction in the alkaline soils (65% of the total P) followed by neutral soil (35% of the total P), whereas it was less abundant (<4%) in the acidic soil type. Fe-Al-bound P was found to be highest for acidic soil (65% of the total P). Soils under the inoculation with Glomus mossae and control gave the highest and lowest values (15.63 mg kg−1 and 10.74 mg kg−1 respectively) for the labile fraction which was similar to the organically bound residual fractions of P (200.17 mg kg−1 and 193.66 mg kg−1 respectively. Inoculation of the soils with AM fungi leads to the redistribution of P fractions in different soils which consequently helps in improvement of available P in soil conducive for plant uptake. [ABSTRACT FROM AUTHOR]

A field experiment was conducted at Research farm of Bihar Agricultural University, Sabour with Katarni rice cv Bhagalpur Katarni during kharif season of 2017. The experiment was laid out with ten organic treatments in Randomized block design (RBD) with three replications. Results revealed that the maximum microbial population viz., Bacteria, Actinomycetes, Fungi, Azospirillum, PSB and KSB (71.66, 27.33, 57.66, 43.66, 63.00 and 47.66 cfu × 105 g-1 oven dry soil) were recorded under treatment T5 {(75 % N (FYM) basal + 25 % N (V/C) at 25 DAT + Azospirillum@ 5 kg ha-1 + PSB @ 5 kg ha-1 + KSB @ 5 kg ha-1)} at panicle initiation stage trend was similar at harvesting stage. The treatment T5 significantly increased dehydrogenase activity by 81.62%, 10.80%, 24.86%, 15.66%, 17.83% and 18.91% when compared with application of T1 (RDF), T3 {(100 % N FYM) as basal)}, T7 {(100 % N (GM)}, T8 {(50 % N (GM) + 50 % N (V/C) at 25 DAT)}, T9 {(75 % N (GM) + 25 % N (V/C) at 25 DAT + Azospirillum@ 5 kg ha-1 + PSB @ 5 kg ha-1 + KSB @ 5 kg ha-1)} and T10 {(75 % N (GM) + 25 % N (V/C) at 25 DAT + Panchagabhya on foliar application)}, respectively. The maximum grain yield of paddy (27.39 q ha-1) was also recorded under treatment T5 which was found to be most effective in modifying soil microbial population, microbial community structure and grain yield of scented rice. [ABSTRACT FROM AUTHOR]

The present study was undertaken to fractionate partially acidulated phosphate rock (PAPR) and evaluate its effect on Phosphorus availability in alluvial soils. For this purpose, low grade phosphate rock was collected from Udaipur, Rajasthan and acidulated at different degrees with sulphuric acid (H2SO4) (v/v)Results from an incubation study showed that the available fraction of P [Water soluble (WSP) and Citrate soluble (CSP)] increased with increasing degree of acidulation. The maximum WSP was obtained at 50% H2SO4 (52.30% of total P) and the maximum CSP was obtained at 80% H2SO4 (49.54% of total P). 50 % dissolution of rock phosphate was the best treatment and found to be at par with that of 60% and 80% but was significantly superior to rest of the treatments. The maximum WSP in the soil samples was obtained after acidulation with 50 %H2SO4 and the maximum Olsen's P by the 14th day of incubation. An increasing trend was found at initial stages of incubation (7-14 days) with a notable decrease in the later stages. WSP demonstrated the maximum correlation at 40% dissolution(r = 96* for first order reaction, r =95* for second order reaction) while for Olsen's P, the maximum correlation was found in initial rock phosphate sample (r =88* for first order reaction, r =94* for second order reaction). Kinetics analysis of the obtained rock phosphate demonstrated that the PARP has more influence on phosphorus release pattern as compared to the inorganic P (SSP). [ABSTRACT FROM AUTHOR]

Transition metal catalysed formation of Csp2‐S bond through cross‐coupling reaction stands important and powerful tools in synthetic organic chemistry. The reaction constitutes an important strategy for the synthesis of thioethers that possess diverse biological activities in medicine and agriculture. Nonetheless, maintaining reaction temperature during Csp2‐S cross‐coupling reaction decides fate of desired product along with possibility of by‐product and disulfides. The economy of process, safety and environmental issue demands thioether synthesis at mild condition and room temperature. Only very few reactions were successful under mild condition using Pd, Cu, Ni, Ni−Ir and Ir catalyst. The current prospective summarizes the best protocols used for efficient Csp2‐S cross‐coupling reactions by transition metal catalyst under mild condition. [ABSTRACT FROM AUTHOR]

Objectives: The primary objective of the study was to compare the number of patients with febrile seizure recurrence within 1 year of presenting to our institute, among patients who received and didn't receive oral iron supplementation. Materials and Methods: This prospective intervention study with historical controls was conducted to compare the number of patients with febrile seizure recurrence within 1 year, among patients who received and did not receive oral iron supplementation. The intervention group additionally received prophylactic iron supplementation of 20 mg biweekly for 1 year. Results: A total of 53 patients each were enrolled in both the groups, with comparable baseline characteristics. Although there was a trend toward a lower rate of recurrence of febrile seizures in the interventional group, as compared to the control group, it did not reach the point of statistical significance (P = 0.35). Both in the worst-case scenario and best-case scenario, there was a trend toward less risk of recurrence of febrile seizure in the intervention group, but it did not reach the point of statistical significance (P = 0.43 and 0.52). For the original scenario, worst-case scenario, and best-case scenario, the absolute risk reduction was 6.5%, 7%, and 6%, respectively, with corresponding number needed to treat (NNT) being 15, 14, and 16, respectively. The trend for absolute risk reduction was more pronounced in those with complex febrile seizures with an NNT of 6.5, but it still did not reach the point of statistical significance (P = 0.16). Moderate/severe IDA was also found to be an independent risk factor for recurrence of febrile seizure in the intervention group (P = 0.03). Conclusion: Oral serum iron supplementation does not significantly reduce the recurrence rate of febrile seizures in children aged 6-60 months. However, there is a trend toward reduction in the frequency of recurrence of febrile seizures, which is more pronounced in the subset with complex febrile seizures. [ABSTRACT FROM AUTHOR]

Two brilliant outcomes of supramolecular self-assembly directed, low molecular weight organic gelator based self-healable Co(II) and Ni(II) metallogels were achieved. Adipic acid as the low molecular weight organic gelator and dimethylformamide (DMF) solvent are employed for the metallogelation process. Rheological analyses of both gel-scaffolds reveal mechanical toughness as well as visco-elasticity. Thixotropic behaviours of both the gels were scrutinized. Morphological variations due to the presence of two different metal ions with diverse metal–ligand coordinating interactions were established. The mechanistic pathways for forming stable metallogels of Co(II)-adipic acid (Co-AA) and Ni(II)-adipic acid (Ni-AA) were judiciously developed through infrared absorption spectral analysis. The nonlinear optical properties, such as the third-order process, of these synthesized metallogels were scrutinized by means of the Z-scan method at a beam excitation wavelength of 750 nm by a femtosecond laser with different excitation intensities ranging from 64 to 140 GW cm−2. The third-order nonlinear optical susceptibility (χ(3)) of the order of 10−14 esu was obtained from the measured Z-scan data. Both the metallogels exhibit positive nonlinear refraction and reverse saturable (RSA) absorption at high-intensity excitation. Co(II) and Ni(II) metallogels show nonlinear refractive indices (n2I) of (3.619 ± 0.146) × 10−6 cm2 GW−1 and (3.472 ± 0.102) × 10−6 cm2 GW−1, respectively, and two photon absorption coefficients (β) of (1.503 ± 0.045) × 10−1 cm GW−1 and (1.381 ± 0.029) × 10−1 cm GW−1 at an excitation intensity of 140 GW cm−2. We also studied the optical limiting properties with a limiting threshold of 9.57 mJ cm−2. Therefore, both metallogels can be considered promising materials for photonic devices: for instance, for optical switching and optical limiting. [ABSTRACT FROM AUTHOR]

An investigation was carried out to evaluate the response of selected species of mycorrhizae for nutrient acquisition and phosphorus uptake by maize in an alluvial soils of Bihar. The study was undertaken during 2013 wet season (July to December) in a net-house at Bihar Agricultural University. Six treatments along with a control treatment were maintained with three replications for the experiment. Five species of AM fungi collected from TERI (The Energy and Resources Institute) along with a local species from long term litchi orchard (Muzaffarpur), were evaluated on the basis of nutrient acquisition in the soil rhizospeheric region for maize crop. The results obtained clearly show that of all the species of mycorrhizae taken under consideration, Glomus mosseae was found to perform better in terms of nutrient acquisition and uptake of P to plant. The maximum P concentration (7.65 mg kg-1), organic carbon (0.60%) and Zn Concentration (6.48 mg kg-1) and P uptake (was also found with the application of G. mosseae. The AM (Arbuscular Mycorrhiza) species significantly increased the released of P and micronutrients in the soil of rhizospheric region of maize plant. The beneficial effect was more pronounced for the treatment in case of Glomus mossae among all the other species used. This may be due to the higher solubilization power of Glomus mossae for soil nutrients than other species. [ABSTRACT FROM AUTHOR]

AIM: Medical students during their first year of Bachelor of Medicine & Bachelor of Surgery (MBBS) course, find Biochemistry difficult and volatile. In this regard, we studied the feedback from students as well as from teachers about the effectiveness of prevailing teaching aids and methods, so that best teaching aid and method can be adopted to improve their academic performance. METHODS: This study comprises of total 100 students of 1st MBBS course, who have completed the 1st semester of academic year 2012-13 and their 11 teachers. Irrespective of the topic, the students as well as teachers were asked to fill the questionnaires and then grade the teaching aids and methods that were used to teach Biochemistry for the period of 5 months. RESULTS: The results of the study showed that as per the subjective assessment of the lectures concern, students preferred PPT teaching the most. As far as the students' performance was concerned the impact of traditional Chalk and Talk teaching was more than the lectures using transparency and overhead projector (TOHP) and PowerPoint presentations (PPT). But when supplementing chalkboard with PPT or TOHP, the enhancement of the student's preference and performance was much better. This fact was true about teacher's preference also. CONCLUSION: This observation may probably be due to the fact that, inherent deficiency of each teaching aid was compensated by the other. With regard to teaching method, the combination of teaching methods was more effective when compared to didactic lectures. [ABSTRACT FROM AUTHOR]

Using 12 long-term (of 15 to 42 years duration) experiments with different cropping systems under various soils and agro-climatic conditions, we studied how different (inorganic and integrated) nutrient management practices influenced boron (B) availability in soils, and its nutrition of nine crops. To this end, four nutrient management practices viz., NPK (recommended dose of N, P and K), NPK + FYM (farmyard manure), control and fallow, which were common in all the experiments, were selected and their effects on B availability in soils were tested using four commonly used methods viz., hot-CaCl 2 (HCC), KH 2 PO 4 (PDP), mannitol-CaCl 2 (MCC) and hydrochloric acid (HCl) in relation to B nutrition of wheat, rice, cowpea, sorghum, sesame, mustard, groundnut, soybean and lentil. Amounts of B extracted by the four different methods followed the order HCC = HCl > MCC > PDP across the tested soils. Averaged over the extractants, long-term nutrient management practices with NPK + FYM resulted in 15% increases in available B in soil over the control, which produced 20% increase in plant tissue B concentration. Such increases with integrated (NPK + FYM) nutrient management practices maintained available B in soils and plant tissues above its critical limits that supplied adequate amounts of B for nutrition of all the tested crops grown intensively for so many years. A B balance study in six experimental sites showed a net B accumulation over time as irrigation water contained and supplied (130–296 g B ha−1 year−1) more B than removed by harvested crops. Of the four methods used, HCC was the best for assessment of availability of B in soils under long-term cultivation. • 15–42 years integrated NPK supply maintained adequate B in soils and in plants. • Long-term nutrient management caused a positive balance of B in soils. • Hot-CaCl 2 was the best extractant in capturing changes in B availability in soils under LTFE. • B-rich irrigation water and to a lesser extent FYM caused B accumulation in soils. [ABSTRACT FROM AUTHOR]

• Soil properties, clay mineralogy, and rainfall determine fractions and available B. • Relationships between B fractions and its available contents are established. • Rice-based systems mobilize B from inactive residual fraction to available form. • HCC and MCC are suitable to assess available B in soils of Indo-Gangetic Plains. We studied relationships between available B and different fractions of B in soils, and how soil properties, climatic parameters, and cropping systems influenced their contents in soils of the Indo-Gangetic Plains (IGP). Available B in soils was assessed by four methods viz., hot-calcium chloride (HCC), mannitol-calcium chloride (MCC), hydrochloric acid (HCl) and salicylic acid (SA). Soil B was also separated into five fractions viz., readily soluble B (RSB), specifically adsorbed B (SAB), organically bound B (OrB), oxides bound B (OxB) and residual B (RB). On average, a higher amount of available B was found in soils of the upper and trans region of IGP dominated by illitic minerals compared with a lower amount in the lower region dominated by kaolinitic one. Among the fractions, RB constituted ∼ 89 % of the total, followed by OxB(6.11 %) > OrgB (5.32 %) ≫ SAB (0.46 %) > RSB (0.26 %). Variations in the amount of available B, and its fractions in soils were explained on the basis of variations in soil properties and climatic parameters. For example, most of the fractions of B (SAB, OrgB and OxB) along with its available amount decreased with increasing soil depth due to declining contents of organic C and amorphous Fe- and Al-oxides. Soil properties explained 51–76 % variability in available B, and 27–65 % in different B fractions. Rice-based cropping systems mobilized RB to available (RSB and SAB) and potentially available (OxB and OrgB) fractions. Among the methods used, HCC and MCC were found suitable for assessing available B status in the soils. The study thus explained variations in B availability in rice and non-rice-based cropping systems, predicted its availability, and also identified suitable method(s) for its estimation in soils of the IGP for a better B management. [ABSTRACT FROM AUTHOR]