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Rice is one of the major staples feeding around 3.5 billion people in the world. Rainfed rice area account for 33% of the total world rice production. Its cultivation is vulnerable to changes in temperature and rainfall. Due to global climate changes, it is essential to analyze and characterize the weather parameters like rainfall, temperature, solar radiation etc., over a region for identifying location specific sowing time. A scientific approach based on appropriate understanding of weather resources and its application for efficient crop management can help in achieving higher productivity. Various studies revealed that changes in microclimate by altering sowing dates has great role to play during vegetative and reproductive stages of the crop and also nutrient content and its uptake which ultimately affects the yield potential. Studies also showed that delayed sowing and transplanting time can significantly affect on the infestation of pest and diseases.

The concept of organic agriculture is receiving increased attention and organic food markets are also expanding quite fast in many parts of the world including India. Development of production technology particularly appropriate nutrient management strategy for organic baby corn is necessary for realizing higher yield and economic returns as well as soil health aspect. Most of the organic manures are low in nutrient contents, which are not sufficient to meet the nutritional requirement of the crops with smaller quantities, especially when inorganic fertilizers are not applied. Under such circumstances, enrichment of organic manures and composts with permitted additives like rock phosphate and beneficial microbial cultures is a feasible option for nutrient supplementation in organic food production. Microbial enrichment technique with bio-inoculants to composting material had been shown to improve the quality of compost. The enrichment of the organic manures with beneficial microbial cultures will further contribute to the enhancement of N and P contents through nitrogen fixation and phosphate solubilization. Hence, the enriched organic manures and their combination provide an ideal nutrition strategy for the crop. There is the possibility of increasing the nitrogen content of compost by inoculation with nitrogen-fixing organisms and the phosphorus content by the inoculation with phosphate solubilizing bacteria. Improved manures will play a major role in organic farming since the method of production is simple and easy.

A new ZnO@SBA-15 nanocomposite material has been fabricated by an “in situ” generation of ZnO NPs on SBA-15 support. The as-synthesized nanocomposite material was fully characterized with various spectroscopic techniques and their catalytic activity was tested for the synthesis of a diverse range of dihydropyrimidinones (DHPMs) and thione derivatives via Biginelli condensation reaction. The catalytic efficiency of ZnO@SBA-15 nanocomposite was far superior with a remarkably lower catalyst loading and shorter reaction time compared to unsupported ZnO nanoparticles. The catalyst was recycled for minimum of four times without significant loss in its catalytic activity. Moreover, a tentative catalytic cycle for the reaction is also proposed.

A field experiment was conducted during the rabi season of 2016-17 to study the effect of nutrient management and moisture conservation practices on yield attributing characters, yield and economic return of organic baby corn grown in a sandy loam soil under rainfed condition. The experiment was laid out in RBD factorial design with three replications. PAC 321 was used as the test variety of baby corn. Among the treatments enriched compost @ 2.5 t ha-1 has shown the significantly better results with respect to yield attributing characters and cob yield followed by application of FYM @ 2.5 t ha-1+lime+ash (1000:10:1). Treatments with straw mulch @ 2 t/ha recorded significantly higher results with respect to different yield attributing characters, cob yield, green fodder yield and high monitary return with B:C ratio.

The present work reports the synthesis of well dispersed palladium nanoparticles immobilized on an amino functionalized nanoscale metal–organic framework MIL-101(Cr), by using a facile polyol method. The resulting Pd/NH2-MIL-101(Cr) nanocomposite is established to be an active heterogeneous catalyst for oxidative amination of aldehydes under solvent free conditions using hydrogen peroxide as an oxidant. The synthesized Pd/NH2-MIL-101(Cr) is characterized by powder X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, field emission scanning electron microscopy, Brunauer–Emmett–Teller (BET) surface area analysis, Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA) and atomic absorption spectroscopy (AAS). The catalyst could easily be recovered and recycled without any significant loss of its catalytic activity.

Sulfonic acid-functionalized MIL-101(Cr) was established to be an active heterogeneous catalyst for the one-pot synthesis of 2-amino-4H-chromenes via a three-component condensation reaction between resorcinol, malononitrile and a diverse range of aromatic aldehydes in aqueous medium. Here, sulfonation of the parent MIL-101(Cr) has been carried out through a post synthetic modification (PSM) technique. The resulting MIL-101(Cr)–SO3H has been characterized by employing powder X-ray diffraction, N2 sorption, FESEM, EDS, FT-IR and TGA studies. Furthermore, the catalyst can easily be recovered and recycled without much change in catalytic activity.

In this study, well dispersed gold nanoparticles (Au Nps) were embedded on an amine-functionalized nanoscale metal–organic framework MIL-101(Cr) via a simple solution approach. The resulting Au/NH2-MIL-101(Cr) exhibited a high isoelectric point (IEP) value with Bronsted basic sites that played an important role in determining the size and dispersion of Au Nps onto its matrix. In addition, the uniform nanomorphology of the catalyst provides the advantage of its good dispersion in aqueous media. The synthesized Au/NH2-MIL-101(Cr) catalyst was successfully characterized by different analytical techniques like powder X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, Brunauer–Emmett–Teller (BET) surface area analysis, Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), zeta potential analysis and atomic absorption spectroscopy (AAS). The catalytic activity of the synthesized material was explored for the epoxidation of styrene using tert-butyl hydroperoxide as oxidant. The catalyst could easily be recovered and recycled up to the fourth catalytic cycle without any significant change in its catalytic activity.

A field experiment on agronomic biofortification in rice varieties through zinc fertilization under aerobic condition was carried out at Assam Agricultural University, Jorhat during autumn season of 2014. Among the Varities, Inglongkiri recorded significantly higher grain yield (21.09 q/ha) followed by Banglami (19.88 q/ha) under aerobic condition. Application of ZnSO4 @ 25 kg/ha + foliar spray @ 0.5% at 3 stages recorded the highest grain yield (21.46 q/ha) followed by application of ZnSO4 @ 25 kg/ha + seed priming with ZnSO4 (2%) (20.72 q/ha). The lowest grain yield was recorded in control treatment (16.47 q/ha). Highest grain Zn content (32.03 mg/kg) and Zn content of brown rice(without polish) (26.81 mg/kg) was noticed in Inglongkiri. Application of ZnSO4 @ 25 kg/ha as basal + foliar spray @ 0.5 % at three stages reveals significantly highest Zn content in grain (35.09 mg/kg) and brown rice (28.31mg/kg).

Keggin-type phosphotungstic acid (H 3 PW 12 O 40 , PTA) encapsulated in the mesocages of chromium-based terephthalate metal–organic framework (MIL-101) was established to be an active heterogeneous catalyst for three component Biginelli condensation reaction with excellent yields (75–90%) and selectivity under solvent free condition. Here phosphotungstic acid can be effectively incorporated into the matrix of MIL-101 by an impregnation method. The synthesized PTA@MIL-101 was characterized by employing various spectroscopic techniques as well as different analytical methods. Moreover, the catalyst could easily be recovered and recycled without any significant loss of its catalytic activity.

We have synthesized Fe 3 O 4 nanoparticles on mesoporous SBA-15 by an “in situ” approach. The synthesized nanocomposite material was well characterized using wide and low angle XRD, N 2 adsorption–desorption isotherm, TEM, FTIR, XPS, and VSM analysis. The Fe 3 O 4 @SBA-15 nanocomposite material was used as a magnetically recoverable catalyst (MRC) for three component coupling reaction of aldehyde, amine and alkyne. The reported catalyst was recycled up to five times without significant loss in its catalytic activity.

ZnO nanomaterials of different morphologies are synthesized by different methodologies. These semiconductor photocatalysts are potentially explored for self-sensitized photodegradation of malachite green (MG) dye in water in a batch reactor. The effects of various parameters like initial dye concentration, catalyst loading, solution pH, light source on degradation efficiency was also investigated. The experimental results showed substantial reduction of COD, besides removal of colour. The photodegradation of MG dye followed the pseudo first order kinetics of Langmuir–Hinshelwood model. The hydrothermally synthesized flower shaped homocentric pencil like ZnO nanorod bundles exhibit excellent photocatalytic activity under solar light. A comparative study of photodegradation efficiency among ZnO nanoparticles, ZnO nanoparticles (hydrothermal) and flower shaped homocentric pencil like ZnO nanorod bundles were also performed. Semiconductor photocatalysis often leads to partial or complete mineralization of organic pollutants. The CO 2 gas evolved due to mineralization of MG was determined using Warburg manometric method under solar light. The possible mechanism of photodegradation under both solar and UV light were also proposed.

Fe3O4 nanoparticles can be effectively incorporated into the matrix of MIL-101(Cr) to fabricate a Fe3O4@MIL-101 magnetite nanocomposite which behaves as a magnetic nanocatalyst for the solvent free oxidation of benzyl alcohol in the presence of TBHP. The composite material is magnetically separable and can be reused several times.

This study investigated the existence of keto-enol tautomers for the first time during the synthesis of aryl-bis(2-hydroxy-1-naphthyl)methane from 2-naphthol and p-tolualdehyde or 4-chlorobenzaldehyde in methanol using CuSO4.5H2O as catalyst under reflux condition. The exclusive formation of aryl-bis(2-hydroxy-1-naphthyl)methanes was observed in dichloromethane at room temperature in the presence of BF3.OEt2/AcOH as catalyst. The keto products were isolated and characterized by 1H NMR, 13C NMR, COSY and DEPT spectra.

Sulfonic acid-functionalized MIL-101(Cr) was established to be an active heterogeneous catalyst for the one-pot synthesis of 2-amino-4H-chromenes via a three-component condensation reaction between resorcinol, malononitrile and a diverse range of aromatic aldehydes in aqueous medium. Here, sulfonation of the parent MIL-101(Cr) has been carried out through a post synthetic modification (PSM) technique. The resulting MIL-101(Cr)–SO3H has been characterized by employing powder X-ray diffraction, N2 sorption, FESEM, EDS, FT-IR and TGA studies. Furthermore, the catalyst can easily be recovered and recycled without much change in catalytic activity.