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Abstract  

The sorption of univalent, bivalent and trivalent ions has been studied on chromium ferrocyanide gel. The studies reveal a high sorption capacity for Cs+, Tl+, Ag+, Cu2+, Zn2+, Cd2+, Fe3+ and Th4+. The sorption of monovalent cations show purely ion-exchange mechanism while the uptake of bivalent and trivalent cations is non-equivalent in nature. Single elution of Rb+, Cs+ and Tl+ has been performed from the columns of this exchanger and the recovery is almost complete in all the cases. Cu2+ and Ag+ get completely adsorbed on the gel column and their elution is not possible probably due to the formation of some new solid phases. Depending on the Kd values of the metal ions, a large number of separations of radiochemical as well as analytical importance can be performed on the columns of this exchanger material.

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The impact of high temperature stress, normally encountered during grain development phases in wheat under late sown conditions, was studied by measuring grain growth rate (mg day−1 grain−1), grain yield (g plant−1) in relation to ADP glucose pyrophosphorylase (AGPase) activity (nmol mg−1 min−1), a key regulatory enzyme in starch biosynthesis. The experimental material comprised nine genetically diverse homozygous genotypes of spring wheat and their six F1s. These were grown in randomised block design with three replications at CCS Haryana Agricultural University, Hisar, India on two dates of sowing 26th November, 2007 (timely, E1) and 24th December, 2007 (late, E2). The rate of grain growth was greatly reduced as temperature increased in late sown environment. Grain growth rate among the parental genotypes was highest in UP 2425 and cross PBW 343 × PBW 435 in both the environments. Mean ADP glucose pyrophosphorylase (AGPase) activity was maximum at 14 days after anthesis in timely sown while in late sown the activity was maximum at 21 days after anthesis in PBW 435, EIGN 1 and EIGN 8 and crosses EIGN 8 × UP 2425, EIGN 1 × Raj 3765 and PBW 343 × PBW 435. A significant positive association in both timely and late sown environments was evident between grain yield and grain growth rate, while in late sown environment, strong positive and significant correlation was observed between grain yield and grain growth rate and also between grain growth rate and AGPase activity in crosses PBW 343 ×WH 283, PBW 343 × WH 542 and PBW 343 × PBW 435. This suggested that increase in grain growth rate and AGPase activities resulted in increase in grain yield and have considerable impact on the yield performance of wheat.

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A study was undertaken to determine the genetics of corn leaf aphid (CLA) resistance in barley under controlled conditions with artificial inoculation at adult plant stage. Inheritance of CLA resistance was investigated in five resistant barley genotypes (EB921, EB2507, Manjula, DL529 and K144) in crosses with susceptible parent Alfa93 in F1, F2, F3 and backcross (BCF1) generations. The aphid inoculation was done using the brush method as well as the detached leaf method. Individual plants were classified in resistant, moderately resistant, susceptible and highly susceptible categories base on number per shoot as well as multiplication of CLA on any of the fresh, young leaf. The plants scored as resistant or moderately resistant were observed twice more at 10 days interval to confirm their reaction. Resistance was governed by a single dominant gene in EB921, DL529 and K144, while it was monogenic recessive in Manjula and EB2507. These diverse sources may be used in breeding for CLA resistance in barley improvement programme.

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Molecular markers provide novel tools for linkage mapping of QTLs of target traits and can greatly enhance the efficacy of breeding programs to improve mineral (iron and zinc) density in rice. A F2 population derived from the cross between high-yielding (PAU201) and iron-rich (Palman 579) indica rice varieties displayed large variation for various physio-morphological traits including grain yield per plant and iron and zinc contents. Transgressive segregation for grain iron and/or zinc contents was noticed in some F2 individuals with one of the F2 plants having exceptionally higher iron (475.4 μg/g) as well as zinc (157.4 μg/g) contents. Grain iron content showed significant positive correlation (r = 0.523) with grain zinc content indicating the feasibility of improving iron and zinc levels simultaneously in rice grain. Two parental rice varieties displayed polymorphism at 76 of the 100 SSR loci, which were used to map the QTLs associated with mineral content in grains. Composite interval mapping (CIM) analysis by Win QTL cartographer 2.5 revealed a total of eleven QTLs for mineral content (eight for Fe and three for Zn) in rice grains on chromosomes 2, 3, 7, 10 and 12.

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Abstract  

Sorption of technetium on hematite colloids, at varying pH (3–10), has been studied in absence and presence of humic acid using 95mTc-96Tc radiotracers. Technetium was found to be weakly sorbed on hematite at lower pH (<5) values, while no sorption was observed at higher pH values. Humic acid was found to have no effect on the sorption of technetium on hematite under aerobic conditions, while at lower pH values small reduction was observed which was attributed to the reduced zeta potential of the hematite colloids owing to the strong sorption of humic acid.

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Summary  

Sorption of inorganic mercury (Hg2+) and methyl mercury, on chemically synthesized polyaniline, in 0.1-10N HCl solutions has been studied. Hg2+ is strongly sorbed at low acidities and the extent of sorption decreases with increase in acidity. The sorption of methyl mercury is very low in the HCl concentration range studied. Sorption of Hg2+ on polyaniline in 0.1-10N LiCl and H2SO4 solutions has also been studied. The analysis of the data indicates that the sorption of Hg2+ depends on the degree of protonation of polyaniline and the nature of mercury(II) chloride complexes in solution. X-ray photoelectron spectroscopy analysis (XPS) of polyaniline sorbed with mercury show that mercury is bound as Hg2+. Sorbed mercury is quantitatively eluted from polyaniline with 0.5N HNO3. Polyaniline can be used for separation and pre-concentration of inorganic mercury from aqueous samples.

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Abstract

The burning rate of AN–HTPB-based propellant catalysed with chromium salt has been studied using conventional strand burner under the various pressure range, i.e. from atmospheric pressure to 6.897 MPa and verified with Piobert law, i.e. r = aP n . At atmospheric pressure, the burning rate AN–HTPB propellant was being accelerated with the chromium-based catalysts used. In case of lead chromate-catalysed system, burning rate was observed 2.655 times higher than burning rate (r = 0.200 mm s−1) of virgin AN–HTPB propellant sample. However, the Copper chromate-catalysed propellant burned with slower rate (r = 0.160 mm s−1) than the virgin AN–HTPB propellant sample. The burning rate of all catalysed propellant samples are found to be the pressure sensitive and accelerated higher with rise of pressure. The highest burning rate (r = 2.422 mm s−1) was recorded with ammonium dichromate and lowest (r = 1.40 mm s−1) with lead chromate-catalysed propellant sample with the rise of pressure up to 6.897 MPa at different pressures. A linear relationship was observed between the burning rate and pressure rise which followed the Piobert law, i.e. r = aP n . The pressure index (n) values of AN–HTPB-based samples were calculated higher when catalysed with ammonium dichromate, Copper Chromate, Cr2O3, Potassium dichromate (n = 0.525, 0.555, 0.429, and 0.408 respectively) and lower (n = 0.226) with lead chromate compared to virgin sample (n = 0.405). Higher value indicates the positive effect on accelerating the burning rate with catalyst at higher pressure ranges.

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Integrated pest management (IPM) strategies for the management of sucking insect pests were disseminated in 36 villages of three districts of Punjab during 2008 to 2010. Adoption of IPM strategies led to reduction in the population of jassid, whitefly and mealybug in IPM villages. Mean population of jassid was 0.62 and 1.60 nymphs per three leaves, whitefly 1.11 and 2.53 adults per three leaves and mealybug 0.53 and 1.03 per 2.5 cm of central shoot in IPM and non-IPM villages, respectively. Mean population of spiders, chrysoperla, coccinellids and predatory bugs was 0.65, 0.13, 0.15 and 0.04 in IPM villages and 0.29, 0.09, 0.06 and 0.00 per plant in non-IPM villages, respectively. IPM strategies resulted in the 47.69 and 50.56 per cent reduction in number of spray and cost of spray in IPM villages over non-IPM villages. The average cost of cultivation was Rs. 21324 ha−1 in IPM villages, as compared to non-IPM villages (Rs. 23774.67 ha−1). Average seed cotton yield in IPM villages was 2333 kg ha−1 in comparison to non-IPM villages (1959.67 kg ha−1) and average net return in IPM villages was Rs. 57194 ha−1, which was Rs. 15709 more than non-IPM villages.

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Our recent findings revealed that the preputial gland of male house rat contains 20 kDa protein, however, the role of androgen in the production of this protein is not known. Hence, the present study was carried out to evaluate the androgen dependency of 20 kDa protein in the preputial gland of house rat (Rattus rattus) and to compare its presence in female clitoral gland. Further, on castration the amount of glandular protein in male was significantly decreased to a certain extent, while testosterone treatment on castrated males showed an increasing trend. The electrophorogram of male house rat showed six different protein fractions with molecular weights of 90, 70, 60, 50, 35 and 20 kDa. However, the 70, 60, 50 and 35 kDa were absent in female. Among the different fractions, 90 and 20 kDa proteins were prominent. On castration, the 20 kDa protein was disappeared; while on testosterone treatment the protein reappeared.  Thus, the present study concludes that the 20 kDa protein is a testosterone dependent sex-associated protein. Since urinary protein is found to act as carrier for volatile substances in pheromonal communication. The present study suggests that the glandular protein may bind with the volatile compounds produced from preputial gland. Identification of this carrier protein in the preputial gland explores the possibility of developing pheromonal trap for rodent pest management (RPM).

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Four species of Lejeunea viz., L. discreta, L. kashyapii, L. mehrana and L. parva are reported here for the first time from Meghalaya. Of which, Lejeunea kashyapii and L. mehrana are endemic, earlier reported from Sikkim only. The taxonomic description and illustrations of all are provided in present communication.

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