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141.
The first Australian record of the lily thrips, Liothrips vaneeckei Priesner, is reported from a bulb farm in Warragul South, Victoria. It is an occasional pest of Lilium bulbs, both in the field and in storage, particularly in the USA and several European countries, and is also infrequently found in considerable numbers on the corms of orchids. 相似文献
142.
Ground beetles were captured in a mixed southern taiga forest near the city of Vologda, Russia, from March to September 2014 using different collection techniques. Of the 250 specimens of ground beetles belonging to 22 species, 109 beetles representing 11 species yielded 326 specimens of mites of the cohorts Gamasina (4 species), Astigmatina (5), and Heterostigmatina (1). Two mite species, Antennoseius pseudospinosus Eidelberg, 1990, a common species in the steppes of southeastern Europe, and Halodarcia incideta Karg, 1969, a polyzonal European hydrophile, are recorded in the taiga zone for the first time. Dorsipes dorsipes Regenfuss, 1968, a specialized parasite of beetles of the genus Carabus Linnaeus, 1758, is new to the fauna of Eastern Europe. An adult mite of the genus Stylochirus G. Canestrini et R. Canestrini, 1882 was found for the first time in a natural hibernating chamber in close contact with an overwintering ground beetle, in particular, a male of S. fimetarius (Müller, 1859) on Carabus granulatus Linnaeus, 1785. The most common mite to occur on ground beetles was Antennoseius bullitus Karg, 1969, which was found on 7 carabid species with the mean occurrence of 41% and comprised 68% of the total mite sample. Joint phoresy of 2–3 mite species was recorded on 12 specimens of ground beetles; in 5 cases the co-occurring mites were Antennoseius bullitus and Stylochirus fimetarius. Three dominant mite species (85% of the total mite sample) were mainly collected off three dominant carabid species (70% of the beetle sample), but individual mite species preferred different hosts. 相似文献
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Bulbs were obtained on onion plants cultured in vitro. No bulbinghappened under long days with fluorescent light and 3040g l1 sucrose. Bulb formation was mainly dependent eitheron sucrose concentration in the culture medium, or on lightspectral composition. Raising the sucrose concentration from40 to 120 g l1 increased plant basal swelling and stoppedfurther vegetative development. These plants were not dormant.When fluorescent light was enriched in incandescence duringa long day period, bulbs were obtained in two months and underwenta consecutive dormancy. Bulb, dormancy, light spectral quality, photoperiod, R: FR ratio, sugar, tissue culture 相似文献
148.
HAO WANG LA QIONG KUN SUN FAN LU YUGUO WANG ZHIPING SONG QIANHONG WU JIAKUAN CHEN WENJU ZHANG 《Molecular ecology》2010,19(14):2964-2979
The uplift of the Qinghai‐Tibetan Plateau (QTP) dramatically changed the topography and climate of Asia and affected the biodiversity of the plateau and its adjacent areas. However, the effects of the uplift on the dispersal, differentiation and adaptation of plants remain a puzzle when the date and processes of the uplift cannot be determined with certainty and the impacts of the Quaternary glaciations on plants on the QTP are unknown. To clarify the relationships among plants on the QTP with the plateau uplift and the Quaternary glaciations, the cpDNA trnT‐trnF regions of 891 individuals from 37 populations of Hippophae tibetana, endemic to the QTP, were sequenced in the present study. A total of 50 haplotypes were found and a strong phylogeographic structure was revealed (NST = 0.854, GST = 0.611, NST > GST, P < 0.01). The results show that three main lineages of the present populations of H. tibetana occupy the western, the middle, and the eastern geographical range, respectively, and their divergence time dates back to 3.15 Ma before present. Of 50 haplotypes, 33 (66%) are private haplotypes, which are restricted to single populations. These private haplotypes are scattered throughout the present geographical range of H. tibetana and originated from multiple differentiations in many lineages during more than 1.0 Ma period, strongly suggesting that multiple microrefugia of H. tibetana existed throughout the present geographical range during the last glacial maximum (LGM) and even earlier glaciations. Additionally, the average elevation of present populations is over 4500 m in the west and the equilibrium‐line of glaciers in the LGM was 500–300 m lower than present in the major interior part of the plateau suggesting that at most sites in the west, LGM microrefugia of H. tibetana may have been above 4000 m above sea level, the highest of all known refugia. Moreover, the divergence times among and within the three lineages and their distinct distributions as well as dispersal barriers support the theory of the recent and rapid uplift of the QTP. The rapid uplift of the plateau within the last 3.4 Ma and the associated environmental changes may have affected the dispersal and differentiation of H .tibetana and shaped its phylogeographic structure. 相似文献
149.
Primary production dynamics and climate variability: ecological consequences in semiarid Chile 总被引:1,自引:0,他引:1
MARIANO DE LA MAZA MAURICIO LIMA PETER L. MESERVE† JULIO R. GUTIÉRREZ‡§ FABIAN M. JAKSIC 《Global Change Biology》2009,15(5):1116-1126
Increase in rainfall variability has important consequences for organisms in arid and semiarid regions around the world. In South American and Australian deserts, the El Niño/Southern Oscillation (ENSO) phenomenon greatly influences rainfall patterns, and therefore the dynamics of plant communities. However, the field data needed to assess the effect of climate change on vegetational patterns is difficult to obtain because of the large spatial scale required for such studies. Normalized Difference Vegetation Index (NDVI) characteristics allow the use of several indexes related to vegetational structure. Due to its direct relationship with primary productivity, it is possible to obtain several measures of annual productivity. These include annual plant yield, annual maximum yield, onset of 'greening-up' and senescence phases, length of the 'green' season, vegetation peak, and therefore, the periods when more or less food is available for herbivores. After verification with ground-truth measures, we used NDVI data from two semiarid localities in north-central Chile (Fray Jorge and Aucó) to determine the relationship between rainfall patterns and vegetation cover and productivity related to El Niño phenomenon. With this information we gauge the influence of climatic processes on primary productivity in western South America, an area subject to strong climate variability. We predict significant variation in Chilean semiarid regions due to climate change, affecting mainly the extent and timing of annual growth season of vegetation, and also including a shorter and delayed greening-up season. Also, we predict that important decreases in rainfall levels will not have strong effects on primary production in these semiarid ecosystems. 相似文献
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