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A better understanding of the relationships between insects and microfungi could help to identify the unknown factors reducing yields in maize. As the first step in current research, the aim was to isolate the microfungal species that can be found in the larval cavity of the European corn borer ( Ostrinia nubilalis Hbn. Lepidoptera. Pyraustidae ) (ECB), one of the most important insect pests of maize. In this way, the scale of potential phytopathogens spread by intermediate hosts could be reduced.Fifty stalk sections damaged by ECB larvae were collected in autumn and fifty in spring on a 20-hectare plot in Ráksi (Somogy county). These were placed in wet chambers and incubated at room temperature under natural light. Identification was done from a pure culture inoculated into potato dextrose agar. Twenty-one species from 14 fungus genera were identified, the majority of which were mitosporic fungi. Species belonging to the Fusarium, Acremoniella and Cladosporium genera were predominant. Most of the species were saprotrophic, though some phytopathogenic species ( Gibberella, Colletotrichum, Nigrospora and Fusarium ) were also identified. The number of genera and the incidence of fungi were much higher in spring samples than in autumn ones, except for Fusarium , where incidence was lower in spring. It was found that failing to harvest the maize significantly enhanced the spread of several fungus species, especially phytopathogenic species, the following year, thereby serving as a source of infection.

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The cotton bollworm (Helicoverpa armigera Hübner), which migrated in the Carpathian-basin from Mediterraneum in the last decades, is becoming an increasingly serious problem for maize producers in Hungary. In several regions the damage it causes has reached the threshold of economic loss, especially in the case of the sweet maize cultivation. The aim of the research was to determine the changing of ears weights and in-kernel accumulation and alteration in grain as a function of cotton bollworm mastication.Our investigation confirmed that there is an in-kernel and protein pattern change of maize grain by cotton bollworm. Our results proved the significant damaging of each part of ears by cotton bollworm masticating (the average weight loss of ears: 13.99%; the average weight loss of grains: 14.03%; the average weight loss of cobs: 13.74%), with the exception of the increasing of the grain-cob ratio. Our examinations did not prove the water loss — that is the “forced maturing” — caused by the damage. Decreasing of raw fat (control: 2.8%; part-damaged: 2.6%; damaged: 2.4%) and starch content (control: 53.1%; part-damaged: 46.6%; damaged: 44.7%) were registered as a function of injury. In contrast, the raw protein content was increased (control: 4.7%; part-damaged: 5.3%; damaged: 7.4%) by maize ear masticating. The most conspicuous effect on protein composition changing was proved by comparison of damaged grain samples by SDS PAGE. Increased amounts of 114, 50, 46 and 35 kDa molecular mass proteins were detected which explained the more than 50% elevation of raw protein content. The statistical analysis of molecular weights proved the protein realignment as a function of the pest injuries, too.

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The aim of present investigations was the increasing of knowledge of the cotton bollworm’s ( Helicoverpa armigera Hbn.) (CB) damages in the different breeding season corns. The damage examinations were made in a 29.2 hectares acreage between Igal and Kazsok villages (Somogy county) on the basis of the flight observation at the end of August 2008. We examined the measure of damages and yield losses based on the collected ears belonging to different breeding season corns (FAO 200–299, FAO 300–399, FAO 400–499, FAO 500–599). The relationship between the breeding season and the damages was examined by variance analysis (one-way anova). The collected samples were examined in analytic laboratory in order to calculate the quantitative alteration of the fundamental in-kernel air dry content values (raw protein, raw fat, starch).Our results proved the significant increasing of damage percentages (FAO 200–299: 8.66%; FAO 500–599: 15.33%), surface damages (cm 2 ) (P = 0.026) and the calculated weight loss of damaged ears (P=0.014) parallel with the increasing of the breeding season length. We confirmed the “forced maturing” in the case of the earlier hybrids in the consequence of the damage. We recorded a decreasing percentage (correlate to the draw matter) of the starch and the raw fat (average decreasing: starch: 1.72; raw fat: 0.26) as well as the increasing starch loss per one hectare, agreeing with the breeding season length increase (starch loss/one hectare: FAO 200–299: 1.54%; FAO 500–599: 2.72%). We observed the quantitative increasing of the raw protein as a function of CB’s damage too, which can be explained by a physiological response to the biotic stress.

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Abstract  

95Tc has been produced through -particle activation of a natural niobium target. The carrier-free 95Tc radionuclide has been separated from the bulk target using tri-n-octylamine (TOA) diluted by cyclohexane as extracting agent and HCl, HNO3 as aqueous phase. Solid-liquid extraction has also been carried out with TOA impregnated Kieselguhr mineral acid system. Technetium-95 was recovered from the organic phase by stripping with 0.1M EDTA above pH 9.

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Authors: N. Chakraborty, R. Pal, A. Ramaswami, D. Nayak and S. Lahiri

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  

Polyacrylhydroxamic acid resin synthesized by functionalization of polyacrylamide with hydroxylamine has been investigated for the sorption of plutonium(IV) from carbonate medium, aiming at its application for the removal of plutonium from alkali wash effluent generated during purification of TBP in PUREX process. Batch experiments have been carried out to determine distribution coefficient of plutonium(IV) between this exchanger and various compositions of carbonate medium. Effect of the concentration of sodium carbonate, sodium bicarbonate and pH of the solution on the distribution coefficient have been studied to optimize the conditions for the uptake of Pu(IV) by this exchanger. Column experiments were carried out to determine the practical capacity of the exchanger for plutonium. Elution studies were also carried out to recover the loaded plutonium from the ion exchange column The exchanger displayed good exchange capacity for Pu(IV) from feed solution simulating the conditions of carbonate wash effluent generated in PUREX process. The exchanger also exhibited fast elution of Pu, suggesting the feasibility of using it for the recovery of Pu from carbonate based wash effluent.

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Abstract  

40 MeV -particles have been used to determine oxygen impurity at ppm levels in silicon, copper, and stainless steel, through the radiochemical separation of18F from the matrix. The separation of18F has been carried out by two techniques, viz.(1) distillation of H2SiF6 and (2) precipitation of KBF4 and some modification has been applied in the separation, depending on the nature of interferences from the matrix. Instrumental approach was also carried out to determine the oxygen impurity at 100 ppm in Si matrix because this approach is not possible in Cu and stainless steel samples due to matrix activity.

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