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排序方式: 共有199条查询结果,搜索用时 171 毫秒
191.
PATRICK K. DEVERS DEAN F. STAUFFER GARY W. NORMAN DAVE E. STEFFEN DARROCH M. WHITAKER JEFFREY D. SOLE TOM J. ALLEN STEVE L. BITTNER DAVID A. BUEHLER JOHN W. EDWARDS DANIEL E. FIGERT SCOTT T. FRIEDHOFF WILLIAM W. GIULIANO CRAIG A. HARPER WILLIAM K. IGO ROY L. KIRKPATRICK MICHAEL H. SEAMSTER HARRY A. SPIKER Jr. DAVID A. SWANSON BRIAN C. TEFFT 《野生动植物专论》2007,168(1):1-36
192.
CHRISTINA EBEY HONEYCUTT ROY PLOTNICK 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2005,38(4):345-350
The graphoglyptid ichnogenus Paleodictyon has been alternatively interpreted as a foraging or farming trace; as a subsurface burrow for the habitation of one or more unknown organisms; the remains of a xenophyophore; and as the result of modular growth of an unknown organism. Graph theory and analysis of the geometry of the regular ichnospecies suggests that if the elements of Paleodictyon are interpreted as tunnels, then they are of extraordinary length relative to the size of any likely solitary tracemaker. In addition, because each vertex of the mesh is of degree three, any possible path through mesh requires revisiting in order to travel through the entire network; this makes the minimum path length even longer. These results suggest that it is unlikely that Paleodictyon is the result of subsurface burrowing. 相似文献
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SEXTON ROY; PALMER JANE M.; WHYTE NICHOLA A.; LITTLEJOHNS SUSAN 《Annals of botany》1997,80(3):371-376
The ripening of raspberry fruit (Rubus ideausL. cv Glen Clova)is associated with a climacteric rise in ethylene production.As the fruit pigments change from green to red there is a progressivesoftening, loss of skin strength and a breakdown of cell wallsin the mesocarp. An increase in cellulase (endo-1,4-ß-D-glucanase)in both drupelets and receptacles accompanies these changes.The localization of cellulase in the regions of the fruit associatedwith abscission zones suggest the enzyme may be involved infruit separation as well as softening. Rubus idaeusL; raspberry; fruit ripening; ethylene; abscission; cell wall breakdown; cellulase; endo-1,4-ß-D-glucanase 相似文献
197.
The ability of wheat cultivars (Triticum aestivum) to retard the development of stem rust, Puccinia graminis f.sp. tritici, was evaluated in hill plots for 3 yr at several locations in Minnesota, against single races and mixtures of races. The area under the disease progress curve was a convenient and reliable method for data summation, but the rate of disease development was not. When inoculated with single races (15B2, 32, 113 or 31) or with mixtures of races (11, 15, 15B2, 17, 32, 151), the cvs Exchange, Thatcher, McMurachy, Redman, Kenya 58, Frontana and Idaed retarded stem rust development more than Baart, Prelude and Marquis; Lee was intermediate. The methods and techniques reported should permit selection of cultivars capable of retarding the development of stem rust. 相似文献
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Chimpanzee and Human Mitochondrial DNA 总被引:1,自引:0,他引:1