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101.
Renne PR Melosh HJ Farley KA Reimold WU Koeberl C Rampino MR Kelly SP Ivanov BA 《Science (New York, N.Y.)》2004,306(5696):610-2; author reply 610-2
102.
An inventory of published data on the natural evolution of forest-steppe, steppe, and semidesert soils in the southern part of the East European Plain and in the southern Trans-Ural region during the Subboreal period of the Holocene has been performed. Schematic maps of the thickness of soil humus profiles and the depth of soil carbonates have been developed for the chronosections of 5000–4200, 4100–3900, and 3800–3200 years ago. On this basis, the areas with specific patterns of natural evolution of soils in the Subboreal period are delineated. 相似文献
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J. Encheva H. Köhler W. Friedt F. Tsvetkova P. Ivanov V. Encheva P. Shindrova 《Euphytica》2003,130(2):167-175
Immature zygotic embryos from the American fertility restorer line RHA-857 were used as donor material for induction of direct
organogenesis in sunflower (Helianthusannuus L.). The range of spontaneous somaclonal variation among the progenies of regenerants was studied. The genetic modifications
observed in regenerants included agronomic traits such as oil content in seed, 1000 seed weight, plant height, leaf width,
leaf length, petiole length, internode length, head diameter, number of branches, length of branches, number of ray florets,
seed width, seed length, and seed thickness. RAPD molecular analysis carried out on sunflower materials in the R-11 generation
showed the absence of a specific 358 bp band in somaclonal line 11/2/51 R. This line showed a modified architecture, full
resistance to Phomopsis helianthiand higher oil content in seed in comparison to the standard RHA-857. Line31/3/53 R was with modified architecture and higher
1000 seed weight. Hybrid No. 144 produced with the participation of somaclonal line 20/5/52 R demonstrated high production
capacity, shorter vegetation period and reduced height. The combination of these favourable changes is desirable in breeding
work on sunflower. Somaclonal variation through director ganogenesis has facilitated the creation of genetically heritable
variation in sunflower, which can be used with great success for hybrid seed production of highly productive hybrids.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
105.
G.?GeorgievEmail author V.?Sakalian K.?Ivanov P.?Boyadzhiev 《Journal of pest science》2004,77(3):151-153
Seven xylophagous insect species were established in stems and branches of Salix caprea L. during the period 1998–2003 in Bulgaria: Agrilus lineola lineola Redtenbacher (Coleoptera: Buprestidae), Aromia moschata (Linnaeus), Oberea oculata (Linnaeus), Saperda populnea (Linnaeus), Saperda similis Laicharting (Coleoptera: Cerambycidae), Synanthedon formicaeformis (Esper) (Lepidoptera: Sesiidae) and Rhabdophaga clavifex (Kieffer) (Diptera: Cecidomyiidae). From them, six parasitoid species were reared: Dolichomitus mesocentrus (Gravenhorst), Dolichomitus populneus (Ratzeburg) (Hymenoptera: Ichneumonidae), Stephanus serrator (Fabricius) (Hymenoptera: Stephanidae), Aprostocetus metra (Walker), Euderus caudatus (Thomson) (Hymenoptera: Eulophidae) and Billaea irrorata (Meigen) (Diptera: Tachinidae). D. populneus, E. caudatus and B. irrorata were connected with S. populnea; D. mesocentrus and S. serrator with S. similis; and A. metra with R. clavifex. Two parasitoids (A. metra and E. caudatus) had not previously been reported for the fauna of Bulgaria. The parasitoid–host relationships D. mesocentrus–S. similis and S. serrator –S. similis were established for the first time in this study. 相似文献
106.
D. A. Ivanov V. A. Tyulin O. V. Karaseva M. V. Rublyuk N. V. Grits 《Russian Agricultural Sciences》2013,39(3):264-267
Features of existential dynamics of a crop of spring wheat of grade Lada within the limits of agro-landscape moraine hills are investigated. Laws of influence of agroclimatic and landscape conditions on efficiency of culture are revealed. Recommendations on adaptation of manufacture of grain to landscape conditions are given. 相似文献
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Ivanov AV Salmakov KM Olsen SC Plumb GE 《Animal health research reviews / Conference of Research Workers in Animal Diseases》2011,12(1):113-121
During the first half of the twentieth century, widespread regulatory efforts to control cattle brucellosis due to Brucella abortus in the Union of Soviet Socialist Republics were essentially non-existent, and control was limited to selective test and slaughter of serologic agglutination reactors. By the 1950s, 2-3 million cattle were being vaccinated annually with the strain 19 vaccine, but because this vaccine induced strong, long-term titers on agglutination tests that interfered with identification of cattle infected with field strains of B. abortus, its use in cattle was discontinued in 1970. Soviet scientists then began a comprehensive program of research to identify vaccines with high immunogenicity, weak responses on agglutination tests and low pathogenicity in humans, as a foundation for widespread control of cattle brucellosis. While several new vaccines that induced weak or no responses on serologic agglutination tests were identified by experiments in guinea pigs and cattle, a large body of experimental and field studies suggested that the smooth-rough strain SR82 vaccine combined the desired weak agglutination test responses with comparatively higher efficacy against brucellosis. In 1974, prior to widespread use of strain SR82 vaccine, over 5300 cattle farms across the Russian Federation were known to be infected with B. abortus. By January 2008, only 68 cattle farms in 18 regions were known to be infected with B. abortus, and strain SR82 continues to be the most widely and successfully used vaccine in many regions of the Russian Federation. 相似文献