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  • Author or Editor: R. Pal x
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A small population of hedgehog grass (Echinaria capitata), a new species for the Hungarian flora has been recently discovered in a disturbed grassland of the Villány Mts. Morphological description and the location of discovery are presented in this paper.

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A field study conducted for two years at the Indian Agricultural Research Institute, New Delhi showed that intercropping potato with fenugreek is highly profitable and provides some in-season income to the potato growers. It also serves as an insurance against complete loss of income when the potato prices crash in the market.

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Herbal oil vapours from Hippophae rhamnoides L. (Elaeagnaceae), and Calendula officinalis L. (Asteraceae) were tested for their toxicity against the adults of Sitophilus granarius L.. According to our hypothesis the mentioned oils can become potential bioagents against stored product pests. The results revealed that both studied essential oils exerted strongly toxic effect on S. granarius, but C. officinalis triggered higher mortality. The efficacy (94.62±2.63%) was reached after a 48-h exposure to H. rhamnoides oil at 2 ml kg–1 while the application of 2 ml kg–1 of C. officinalis oil for 24 h produced 98.94±1.00% mortality rate. Insect mortality was hyperbolically-featured, and increased with the duration of the exposure to the examined oils. Mortality was 100% at 5 ml kg–1 of H. rhamnoides after 24-h duration of its application, while with C. officinalis the same value could be reached after a 12-h exposure to the oil. The progeny pronouncedly recovered from the treatment of both essential oils applied.

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Arsenic, the toxic metalloid, widely available in the natural ecosystem, poses serious problem through contaminated groundwater and drinking water. The emerging areas of arsenic hazards in agricultural systems through use of contaminated irrigation water and entry of toxin in crops has been largely overlooked. Arsenic accumulation by plants and its translocation to edible parts were observed to vary within crops and also across the cultivars. Wheat is an alternative choice of summer rice, due to low water requirement. With this background, the current experiment was conducted with four popular wheat cultivars to study the arsenic accumulation and varietal tolerance under different soils and groundwater. The arsenic content was determined by using atomic absorption spectrophotometer (AAS). Result revealed that, wheat cultivars differed in their grain arsenic concentration (0.23–1.22 mg kg−1), which differed across the sites and year of experiment. The arsenic translocation in wheat grains usually least, and accumulation by different tissues followed the order root > stem > leaf > grain across the cultivars. The cultivar UP-262 was found to accumulate least arsenic in grains and cultivar Kalyansona the highest under same growing condition, due to phyto-extraction or phyto-morphological potential of the varieties.

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This paper deals with a new Gypsophila paniculata dominated half-ruderal Pannonian weed association. In order to identify this vegetation type, samples were compared with some dry and semidry Central European weed associations of Agropyretalia repentis. The community studied seems to belong to the Artemisio-Agropyrion repentis alliance. Based on results, the Gypsophila paniculata dominated dry half-ruderal sand grass stands are classified in the frame of a new association under the name of Gypsophilo paniculatae-Agropyretum repentis . It can be divided into two subassociations, notably a more natural typical one rich in species, replacing disturbed sand grasses → typicum with Artemisia campestris , and another type containing less species and exposed to much stronger disturbance → aperetosum spicae-venti subass. nova.

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Abstract  

The solid state reactions between ferrous oxalate dihydrate i.e. FeC2O4.2H2O and unsubstituted/ substituted aniline hydrochlorides have been studied. The products [FeCl/oxH/. AN-Cl] have been characterized by elemental analysis, infrared and Mössbauer spectroscopic techniques. The kinetic studies for the reactions have been performed at various temperatures for fixed particle sizes at constant compaction. The following order of reactivity has been observed: unsubstituted > p-substituted > m-substituted o-substituted.

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Summary  

The bioaccumulation of gold in trace concentration by Nitzschia obtusa and Navicula minima, two members of bacillariophyceae, has been studied. It has been observed that Nitzschia obtusa showed better accumulation of gold in acidic pH in comparison to neutral and basic pH. Maximum accumulation was observed with 1 mg . kg-1 or less   gold concentration. However, the accumulation by the living cells was reduced when the matrix concentration was higher. Navicula minima, on the other hand, found to be a better accumulator of gold in wide ranges of pH and substrate concentration of the media. It was also inferred that the gold accumulation by diatom was mainly due to adsorption by biosilica (siliceous frustules of dead diatom cells). Accumulated gold was recovered with conc. HNO3.

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Abstract  

The bio-sorption of heavy and toxic radionuclides by three genera of algae from different taxonomic groups was studied employing the recently developed 'Tracer Packet' technique. The tracer packet of heavy and toxic metals' contained 197Hg, 198,199,200,201Tl, 199,200,201Pb, 204Bi and 204,205Po radionuclides in carrier-free state and was produced by irradiating a gold metal foil with medium energy 7Li and 12C beams successively in a 12 MV Pelletron. Three genera, Spirulina from Cyanophyceae, Oedogonium from Chlorophyceae and Catenella from Rhodophyceae were cultured in laboratory condition and were used in the experiment. The radionuclide accumulation varied according to different genera at different pH levels. At basic pH Spirulina showed a maximum radionuclide accumulation in comparison to other genera.

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Abstract  

The thermal behaviour of the mixed-ligand complexes of cobalt(II) and copper(I) ions with antipyrine derivatives of 1,2-ethanediamine or piperazine (BAMP and TAMEN), with water and with 2-mercapto-benzothiazole (Hmbt) was investigated. The complexes contain 2-mercaptobenzothiazole (Hmbt, in the case of cobalt(II) ion) or dimercaptobenzothiazine (mbt–mbt, in the case of copper(I) ion) molecules as ligands and perchlorate (ClO4 ) or thiocyanate (SCN – ) ion as counterion. By heating, water and ligands release the solid phase at lower temperature. At higher temperatures process of different organic reactions of ligands (e.g. polymerization, polycondensation) could be suggested to interpret the relative high final mass values.

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Use of high analysis fertilizers such as diammonium phosphate in place of ordinary superphosphate and urea in place of ammonium sulphate over years, sulphur application to crop fields has considerably decreased, which has led to widespread sulphur deficiency in Indian soils. Hence, considering this into account a field study for two years was conducted at the research farm of ICAR-Indian Agricultural Research Institute, New Delhi to evaluate sulphur-coated urea (SCU) as a source of sulphur (S) and an enhanced efficiency of nitrogen fertilizer. Prilled urea (PU) coated with 4 to 5% S significantly increased wheat grain yield to the tune of 9.58 to 11.21% and nitrogen 19.06 to 23.94% and sulphur uptake 21.76 to 29.29% over prilled urea alone by wheat. However, net return and benefit: cost ratio was the highest and significant at 5% S coating onto PU. Five % SCU supplied 50% of the sulphur needs of the wheat crop and enhanced nitrogen recovery efficiency by 60% and is therefore recommended as sulphur as well as enhanced efficiency of nitrogen fertilizer for wheat in Indo-Gangetic plains of India. This is an important finding considering the environmental safety by increased nitrogen recovery and also productivity in present scenario.

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