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  • Author or Editor: D. Atanasova x
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Monitoring the seasonal flights of the Latticed heath, Chiasmia clathrata (Lepidoptera: Geometridae), was carried out using home made sticky delta traps baited with pheromone caps purchased from CSALOMON® (Plant Protection Institute, Hungary, Budapest). The monitoring was conducted in alfalfa fields in Pazardzhik and Sofia regions in Bulgaria during 2007–2009. The flight of C. clathrata at the investigated sites started at the very beginning of April and lasted until the middle-end of September. Three relatively well-defined peaks, indicating three generations, were recorded in Sofia region. Thus, the flight period and the flight of the separate generations of the pest were defined more accurately than it has been reported earlier. Pheromone baits, products of CSALOMON ® are potent and species specific tools for detecting the presence and seasonal monitoring of C. clathrata.

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Abstract  

In this study, we explored the possibility of the preparation of a catalytic system for reduction of nitrogen oxides based on alumina and zirconia thin films electrochemically deposited on stainless steel, silver being chosen as an active phase. The composition and structure of the Ag loaded Al2O3/SS and ZrO2/SS films were characterized by SEM, XPS, and XRD. It was established that the electrochemical deposition leads to the formation of an active phase of isolated particles of metal silver with a mean size of several μm. The catalysts were tested in the reaction of selective catalytic reduction of NO x with C8H18 in an excess of oxygen. A higher catalytic activity was found with Ag/ZrO2/SS, the optimum working temperature for both samples being 380 °C.

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Two-year seasonal monitoring of the flight of Phthorimaea operculella by means of pheromone traps was organized at four sites in three districts in Bulgaria: Sofia, Kyustendil and Plovdiv. Comparison between sticky traps and dry funnel traps has shown that sticky traps were much more effective in capturing of males of this pest than the dry ones. The results of our investigations showed that the pest could appear in the field as early as the end of March and also intensive flight could be observed up to the end of November. Single catches were registered even in January. However, because of overlapping of the generations, their number and periods of moth emergence was not possible to be distinguished by the catches in pheromone traps. Analyses of climatic data (mean air temperature and mean rainfall) indicated that none of the climatic variables investigated strongly affected P. operculella trap catches.

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Seventy-six promising bread winter wheat lines were investigated in relation to the allelic composition of grain storage proteins. The aim of the study was: i) to find out a possible relation between wheat quality and the separate low molecular loci and ii) to examine the potential of some of the existing Glu-A3 alleles to increase the quality. Five indices were investigated that covered almost all aspects of grain quality: sedimentation value, wet gluten content, dough stability, bread volume, quality index and valorimeter. The samples for quality analysis were from a 3-year period of investigation. Different statistical approaches were used to study the influence of Glu-A3 on the level of the indices. The LMW-GS were determined by SDS-PAGE (Payne et al. 1980). It was determined that locus Glu-A3 had the strongest influence on quality among the loci, that determine the low molecular glutenins. The Glu-A3 alleles influenced the end-use quality irrespective of the HMW-GS and LMW-GS composition background against which their effect was expressed. There were important variations among the separate alleles of Glu-A3 locus for their direct effect on end-used quality. Glu-A3 f had strong positive effect on the end-use quality against the background of all HMW combinations. Glu-A3 b had a similar positive effect. The Glu-A3 b allele was connected with high quality in wheat but its effect was weaker than that of Glu-A3 f and was not significant for some of the investigated indices.

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Seventy-three common winter wheat varieties developed throughout the breeding history of the DAI were investigated for their diversity of allelic variants on storage proteins component composition in grain. The high- and low molecular weight protein structures were determined by the widely used SDS-PAGE method of Payne et al. (1980). The ratio between the individual alleles on the loci of high and low molecular weight glutenin was analyzed. The change in the HMW-score was followed according to the period when the respective varieties were developed. The configuration Glu-A1 b , GluB1 c , Glu-D1 d , which was established in about 45% of the investigated genotypes, was most frequent in the high-molecular variants of glutenin. Concerning the low-molecular weight glutenins in 21 out of the 73 investigated varieties, the combination Glu-A3 c , Glu-B3 b , Glu-D3 c was observed; it coincided with the spectrum of the widely used variety Bezostaya 1. Highest diversity was established in the allelic variants of Glu-A3, Glu-B3 , in which 6 and 5 alleles, respectively, were observed. The quality of the varieties developed at DAI was relatively high (score 8.1). About a quarter of them are with high end-use quality confirmed in production. This is mainly due to the concentration of “strong” positive alleles in glutenin as a result from the intensive use of parents directly or indirectly related to Bezostaya 1, which lead to decrease of the percent of Glu-B1a (2 + 12). Quality should be further increased by additional diversity of combinations between “possitive” as effect on end-use grain quality alleles. Concerning HMW loci to keep of high grain end-use quality, it is necessary to maintain the status of Glu-A1b (2*), as well as of Glu-D1d (5 + 10).

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