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11.
The parasitoid complex of Paraphytomyza populi (Kltb.) (Diptera: Agromyzidae) was studied in Sofia, Bulgaria in 1997. Poplar leaves with P. populi larvae and pupae were collected from poplar stump shoots and examined in a laboratory. As a result, eleven parasitoid species were established: Chorebus albipes (Haliday) (Hymenoptera, Braconidae), Pediobius metallicus (Nees), Danuviella subplana Erdos, Chrysocharis nephereus (Walker), Chrysocharis pubicornis (Zetterstedt), Diglyphus crassinervis Erdos, Diglyphus isaea (Walker), Diglyphus albiscapus Erdos, Cirrospilus diallus Walker, Cirrospilus pictus (Nees) (Hymenoptera, Eulophidae) and Elasmus sp. (Hymenoptera, Elasmidae). Six species (D. crassinervis, D. isaea, D. albiscapus, C. diallus, C. pictus and Elasmus sp.) have been recorded as new parasitoids of P. populi. The genus Danuviella was found for the first time in Bulgaria. Five species (C. albipes, P. metallicus, D. subplana, D. crassinervis and D. albiscapus) are new records for the fauna of the country. The total mortality of P. populi caused by parasitoids was 19.1% and 49.0% for the overwintering and the summer generations, respectively. P. metallicus was the most important in reducing the pest number.  相似文献   
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Potato wart is one of the most important quarantine diseases of potato in the world. In Georgia, symptoms of wart were first seen in 2009–2013 during observations on potato in home gardens in Khulo district, although they may have been present since 2006. However, potato wart presence was only confirmed by PCR in 2013. Isolates pw13N and pw13 of Synchytrium endobioticum collected from the infested area of the village Didadjara, Khulo municipality were tested using laboratories in Georgia and the Netherlands in the framework of collaboration between scientists of Batumi State University and the National Plant Protection organization of the Netherlands. Additionally, pot tests were carried out in Georgia. Based on the results obtained, the pathotype found in Georgia is not known from Europe, and based on its reactions this pathotype resembles pathotype 38 (Nev?ehir) detected in (the non‐European part of) Turkey.  相似文献   
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引言 改变植物基因的表达能诱导新型蛋白的形成,或者至少使某些正常蛋白的表达受到抑制,一般都被认为这是植物对各种非生物的、或生物影响因子的典型反应(Mladeno等,1998).至今为止,象组织割裂、渗透逆境、低温、紫外光和γ射线辐照等机械的、或物理的、或生物的诱变方法都有过利用(Edreva,1991),而在某些重要的经济作物上采用辐照诱变,来获得品质改良,如提早成熟,或对某些流行广泛的病害增强的抗性品种则更为普遍.  相似文献   
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本文研究后贝加尔湖春小麦栽培的最适播种期和施用无机肥的配方。研究结果表明:该地区春小麦中熟品种最适宜的播种期是4月末到5月上旬;最佳施肥量及配方为N_(60)P_(60)K_(40)。  相似文献   
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The soil cover patterns in the Kabansk district (the Baikal region of the Buryat Republic), including the Selenga River delta, are analyzed. A soil map of this area has been developed on a scale of 1 : 500000. Stony organic soils are widespread in the tundra zone. Mountain-meadow soddy soils and tundra podburs (under dwarf pine) are formed at lower heights around lakes and in glacial valleys. Kabansk district includes taiga landscapes on the northern slopes of the Khamar-Daban Ridge with the predominance of podburs, podzols, soddy-taiga soils, and burozems. Agrolandscapes occur in the Nizhneselenginsk meadow-bog and forest-steppe natural region with a predominance of soddy forest, soddy gray forest, meadow, alluvial, meadow-bog, and bog soils. Data on the land evaluation in the agricultural part of the studied region are given.  相似文献   
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A previous study indicated decreased DNA content of chromosome 4A in the wheat (Triticum aestivum L. cv. Tähti) compared to cvs. Chinese Spring and Rennan. Here we show that the lower 4A DNA content is associated with a specific haplotype in the distal part of 4AL. In 41 cultivars of bread wheat (T. aestivum L.), including cv. Tähti, a common haplotype was identified in the linkage disequilibrium region on the long arm of chromosome 4A (4AL). The haplotype (haplotype A) is characterized by 7 SSR and 5 EST marker alleles, including five zero-alleles. Haplotype A was found in 46 % of the Swedish/Finnish/Estonian spring wheat genotypes, while only one of the modern wheat accessions from Germany carried the same haplotype. Fluorescent cytometry analysis linked haplotype A to diminished DNA content of chromosome 4A. The haplotype was introduced into the Canadian and US breeding programs at the beginning of the twentieth century (cvs. Marquis, Thatcher, Ruby) from the common progenitor, the Polish landrace Fife, and it is still found in modern wheat germplasm in these countries. Zero-alleles characteristic for haplotype A were also detected in several accessions of European spelt (Triticum spelta L.), and in two accessions of tetraploid Triticum timopheevii Zhuk. The presence of haplotype A in European spelt indicates the considerable antiquity of the haplotype, as it must have been inherited from the hexaploid or tetraploid parent of spelt in at least one hybridization event.  相似文献   
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A map of soil cover patterns in the Tugnuisk Depression of the Transbaikal region has been compiled on a scale of 1:500 000. This map contains information on the distribution of soil complexes and soil combinations and on the genetic and geometric characteristics of soil areas. It is derived from the original large-scale soil maps. The theory of soil cover patterns was used as the basis for cartographic generalization. This made it possible to preserve information on soil types and subtypes identified on the original maps and to show the real distribution pattern for all the components of the soil cover.  相似文献   
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