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K. L. McLean † J. Swaminathan ‡ C. M. Frampton J. S. Hunt H. J. Ridgway A. Stewart 《Plant pathology》2005,54(2):212-218
The rhizosphere competence of the biological control agent Trichoderma atroviride isolate C52 was studied on onion roots both in the glasshouse and in the field when introduced into soil in a range of formulations. Proliferation of T. atroviride in the rhizosphere was formulation-dependent. A pellet formulation maintained the fungal concentration at 105 cfu per g soil, whereas solid-substrate and seed-coating formulations gave concentrations of 104 and 101 cfu per g soil, respectively. To facilitate rhizosphere-competence studies, a UP-PCR band profile generated with primer L45 for isolate C52 was used to enable conclusive identification of T. atroviride C52 when recovered from soil. When isolate C52 was introduced into Sclerotium cepivorum -infested soil as both pellet and solid-substrate formulations, there was no statistically significant difference in the disease control between these treatments, but the pellet treatment doubled the percentage of healthy plants compared with the control treatment. 相似文献
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Monnier JD Zhao M Pedretti E Thureau N Ireland M Muirhead P Berger JP Millan-Gabet R Van Belle G Ten Brummelaar T McAlister H Ridgway S Turner N Sturmann L Sturmann J Berger D 《Science (New York, N.Y.)》2007,317(5836):342-345
Spatially resolving the surfaces of nearby stars promises to advance our knowledge of stellar physics. Using optical long-baseline interferometry, we constructed a near-infrared image of the rapidly rotating hot star Altair with a resolution of <1 milliarcsecond. The image clearly reveals the strong effect of gravity darkening on the highly distorted stellar photosphere. Standard models for a uniformly rotating star cannot explain our findings, which appear to result from differential rotation, alternative gravity-darkening laws, or both. 相似文献
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Water frost absorptions have been detected in the infrared reflectivities of Jupiter's Galilean satellites JII (Europa) and JIII (Ganymede). We have determined the percentage of frost-covered surface area to be 50 to 100 percent for JII, 20 to 65 percent for JIII, and possibly 5 to 25 percent for JIV (Callisto). The leading side of JIII has 20 percent more frost cover than the trailing side, which explains the visible geometric albedo differences between the two sides. The reflectivity of the material underlying the frost on JII, JIII, and JIV resembles that of silicates. The surface of JI (Io) may be covered by frost particles much smaller than those on JII and JIII. 相似文献