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Plantlets of Limonium estevei Fdez. Casas, an endangered Spanishspecies, were successfully regenerated from nodal segments excisedfrom young seedlings. Initiation of multiple adventitious budswere obtained in MS modified medium plus 1 mg l1 IBAand 0·1 mg l1 BAP. Rooting was achieved by transferof the isolated shoots to fresh MS medium without plant growthregulators. Fully grown plants were established in a pottingmix and are growing well in a greenhouse. Limonium estevei, in vitro multiplication, adventitious regeneration 相似文献
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Susceptibility to Phosphomycin as a Differential Character for Gram Negative Anaerobic Bacilli 总被引:1,自引:1,他引:0
J. A. GARCIA RODRIGUEZ J. PRIETO PRIETO J. E. GARCIA SANCHEZ M. C. SAENZ GONZALEZ F. MARTIN LUENGO 《Journal of applied microbiology》1976,41(2):251-254
On the basis of their sensitivity to phosphomycin, various species of anaerobic Gram negative bacilli examined fell into one of two groups. All strains of Bacteroides were resistant to 500 umg/ml whereas strains of Fusobacterium were uniformly sensitive to 62.5 μg/ml. Disc sensitivity testing to phosphomycin at concentrations of 200–500 μg/ml provides a reliable and rapid means of distinguishing fusobacteria from bacteroides. 相似文献
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KEVIN D. CHASE DAVE KELLY ANDREW M. LIEBHOLD MARTIN K.‐F. BADER ECKEHARD G. BROCKERHOFF 《Ecological Entomology》2017,42(2):173-183
1. Dispersal and host detection are behaviours promoting the spread of invading populations in a landscape matrix. In fragmented landscapes, the spatial arrangement of habitat structure affects the dispersal success of organisms. 2. The aim of the present study was to determine the long distance dispersal capabilities of two non‐native pine bark beetles (Hylurgus ligniperda and Hylastes ater) in a modified and fragmented landscape with non‐native pine trees. The role of pine density in relation to the abundance of dispersing beetles was also investigated. 3. This study took place in the Southern Alps, New Zealand. A network of insect panel traps was installed in remote valleys at known distances from pine resources (plantations or windbreaks). Beetle abundance was compared with spatially weighted estimates of nearby pine plantations and pine windbreaks. 4. Both beetles were found ≥25 km from the nearest host patch, indicating strong dispersal and host detection capabilities. Small pine patches appear to serve as stepping stones, promoting spread through the landscape. Hylurgus ligniperda (F.) abundance had a strong inverse association with pine plantations and windbreaks, whereas H. ater abundance was not correlated with distance to pine plantations but positively correlated with distance to pine windbreaks, probably reflecting differences in biology and niche preferences. Host availability and dispersed beetle abundance are the proposed limiting factors impeding the spread of these beetles. 5. These mechanistic insights into the spread and persistence of H. ater and H. ligniperda in a fragmented landscape provide ecologists and land managers with a better understanding of factors leading to successful invasion events, particularly in relation to the importance of long‐distance dispersal ability and the distribution and size of host patches. 相似文献