Characteristics of natural growing areas for Leucojum aestivum L. in Bulgaria based on chemical composition of plants

The characterization Bulgarian natural growing areas of Leucojum aestivum L. was on the basis of the chemical composition of the plants and some soil characteristics which give an opportunity to choose those conditions suitable for growing and obtaining enlargement of the source of plant material with high galanthamine content. This information should benefit the improvement of natural growing areas for Leucojum aestivum L. as well as for the creation of new industrial plantations.     

Culture selected somaclonal variation in five Triticum aestivum L. genotypes

Somaclones (R₃ and R₄ generations) regenerated from five winter wheat (Triticum aestivum L.) genotypes were evaluated for variation in agronomic and morphological characters. Immature embryos were used as initial explant material. Comparisons for plant height, top internode length, spike length, number of seeds per spike and 100 seed weight were made between the somaclones and their parents. Some morphological variations of stem and spike characteristics were registered which demonstrate that plant height and spike length can be changed by using immature embryo culture. The results obtained may be considered a biotechnological contribution to wheat plant improvement. This revised version was published online in August 2006 with corrections to the Cover Date.     

Changes in Lipid Composition After In-Vitro Selection for Glyphosate Tolerance in Tobacco

After a one-step selection procedure with glyphosate added to the callus medium, tobacco regenerants were obtained from calluses surviving on field doses of the herbicide. The lipid and sterol compositions of potted plants from the two original cultivars which underwent the selection procedure but without glyphosate, and the selected regenerants were investigated. Controls were derived from micropropagation and not from seeds. They served as appropriate controls for comparison with glyphosate regenerants, i.e. they underwent exactly the same experimental conditions except for the glyphosate treatment. Plant regeneration was strongly (at one-step selection) or fully (at stepwise selection) inhibited. Only a few glyphosate-tolerant plants (seven of Nevrokop A₂₄ and five of Zlatna arda) were obtained which were cloned and potted. At least 10 plants of one clone per genotype were used for the further biochemical analyses. The spraying of the tobacco plants from the cultivars with glyphosate led to a decrease of monogalactosyl diacylglycerol content and increase of the saturated fatty acids in all glycolipid classes. The concentration of stigmasterol increased and that of sitosterol decreased only in Zl.arda variety. In the regenerants there were different changes in lipid composition, concerning mainly a decrease of monogalactosyl diacylglycerols (MGDG) and an increase of digalactosyl diacylglycerols (DGDG) in Zl.arda-derived regenerants and increase of the amounts of neutral lipids and decrease of phospholipids (PL) in the Nevrokop A₂₄-derived regenerants. Surprisingly, after treatment of the regenerants with glyphosate, the MGDG amounts in these regenerants were higher than in the controls, which could mean a lesser ability to control ion permeability.     

Low variability of flower volatiles of Rosa damascena Mill. plants from rose plantations along the Rose Valley, Bulgaria

The composition of volatile compounds in the rose essential oils obtained from the rose flowers has been known to be affected by a number of factors including the region of rose growing. The variations of the flower volatile composition of Rosa damascena plants growing in 11 different rose plantations along the famous Rose Valley in Bulgaria were studied following GC/MS metabolite profiling. ANOVA statistical test revealed that only 14 of a total of 90 identified compounds were significantly influenced by the geographic location of the sampled rose plantation. The hierarchical clustering analysis based on the subset of these 14 compounds revealed no clear correlation between the levels of rose flower volatiles and geographic location of the studied rose plantations. The results from the study suggest low variability of rose flower volatiles accumulation and elevated plasticity of the common R. damascena genotype industrially cultivated in the Rose Valley.     

保加利亚主要鲜食葡萄品种评价

保加利亚位于巴尔干半岛的东南部．属于温带气候．北部略受大陆性气候影响,南部带有地中海气候特点．气候和土壤等自然条件非常适宜葡萄种植．是世界著名的葡萄与葡萄酒生产国之一。长期以来．保加利亚的农业科研机构非常注重鲜食葡萄品种的选育研究．     

保加利亚的苹果生产与研究

保加利亚气候条件非常适宜苹果生长.1968年保加利亚苹果种植面积为3.04万hm2,但近年由于土地改革,苹果种植面积持续减少,现仅存5393hm2.笔者介绍了目前保加利亚苹果的种植面积、产量、主栽品种、砧木、树形及研究状况.     

Agronomic performance and molecular assessment of tissue culture-derived barley lines

In order to assess the genetic variability among regenerants. field trials were conducted with 64 barley lines derived from tissue culture (TCD lines) of four Bulgarian barley varieties. The results indicate that the agronomic performance was altered by tissue culture regeneration and the frequency of variation was cultivar dependent. Seven TCD lines showing desirable agronomic characters were selected in the SC1₆ progeny. Molecular markers (protein, restriction fragment length polymorphism (RFLP) and random amplified polymorphic DNA (RAPD) have used applied to determine the variability induced by tissue culture. Polymorphism was detected in sequences coding for C-hordeins in line 70 derived from cv.‘Jubiley’Two lines from cv.‘Ruen’exhibited polymorphic bands after hybridization with a mitochondrial DNA probe. RAPD assays have been carried out using 20 different l0-mer primers. Heritable polymorphisms in several TCD lines have been observed.     

Influence of chemical composition of soils on the galanthamine content in Levcojum aestivum

The elemental composition of seven soils of the main geographical regions in Bulgaria for the growth of Leucojum aestivum L. was determined. It was found that a relationship exists between the galanthamine content of the plant and the chemical composition of the soil. These results indicate that galanthamine bio‐ synthesis could be controlled by the soil fertility level.     

Genetic diversity among elite Bulgarian barley varieties evaluated by RFLP and RAPD markers

Genetic variation among five elite winter barley cultivars (H. vulgare L.) currently grown in Bulgaria was assessed at the molecular level using restriction fragment length polymorphism (RFLP) and randomly amplified polymorphic DNA (RAPD) markers. The present study sampled RFLPs in four well characterized multigene families in barley: the seed storage protein loci; the 18S, 5.8S and 26S ribosomal DNA loci; the loci coding for 5S ribosomal RNA and the loci coding subunit α of ATP-A complex in the mitochondrial genome. RFLPs were detected in three out of five investigated chromosomal loci in the barley cultivars studied. RAPD assay using arbitrary 10-base primers was applied to generate amplified length polymorphic markers in barley. Overall a total of 15 polymorphic phenotypes were found among the studied barley cultivars by using 11 out of 25 tested primers. All RAPDs were considered as dominant genetic markers except for two, where PCR and Southern blot analysis indicated the presence of codominant amplification products. Five RAPD polymorphisms in F₁ and F₂ progenies of the cross between Alpha and Obzor were inherited in Mendelian fashion. The determined values for the genetic variation proved a high genetic similarity among the tested cultivars. Genetic similarity (GS) calculated from RFLP and RAPD data ranged from 0.888 to 0.997 with a mean GS – 0.933. This revised version was published online in July 2006 with corrections to the Cover Date.