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ROBIN A. MARRS RUTH A. HUFBAUER STEVEN M. BOGDANOWICZ REN SFORZA 《Molecular ecology resources》2006,6(3):897-899
Centaurea stoebe (subspecies C. s. stoebe and C. s. micranthos[S. G. Gmelin ex Gugler) Hayek] and Centaurea diffusa are Eurasian plant species that have invaded much of North America. We isolated seven microsatellite loci from C. stoebe and two loci from C. diffusa. All loci described here amplify in both species and have between six and 25 alleles each. These markers will be useful in examining population structure and addressing questions regarding these invasions. 相似文献
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WALTER MAJAK RUTH E. McDIARMID THOMAS W. POWELL ALBERT L. VAN RYSWYK DARRYL G. STOUT RICHARD J. WILLIAMS RICHARD E. TUCKER 《Plant, cell & environment》1979,2(4):335-340
Abstract. The alkaloids of reed canarygrass respond to changes in soil moisture and nitrogen fertility. Gramine and hordenine levels increased under field conditions of moisture deprivation and this effect was enchanced when nitrogen fertilizer was applied. The level of 5-methoxy-N-methyltryptamine was affected mainly by the nitrogen amendment. Exceptional alkaloid levels in reed canarygrass are interpreted in relation to climatic and plant osmotic parameters. Improved TLC fluorescence scanning procedures are presented for quantifying reed canarygrass alkaloids. 相似文献
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I. S. BEN-ZE'EV M. BAR-JOSEPH Y. NITZAN RUTH MARCUS 《The Annals of applied biology》1989,114(2):293-300
A rapidly spreading decline of ‘Minneola’ tangelos, ‘Shamouti’ and ‘Valencia’ sweet oranges grafted on sour orange rootstock in the Morasha area, in the coastal plain of Israel, was found to be caused by a severe ‘seedling yellows’ strain of the citrus tristeza virus (CTV). Repeated ELISA tests revealed great variation in distribution of CTV throughout the canopies, even in declining trees. In a substantial number of the declining trees, samples of up to 10 twigs per tree were not always sufficient for CTV detection. The ELISA values (O.D. 405 nm) in the parts found infected were high, whereas in most of the twigs showing negative ELISA results the virus was absent as indicated by biological indexing. The Morasha strain of CTV was also characterised by rapid annual spread rates. The ratio D/E (the proportion of Declining trees found among ELISA-positive ones) is proposed as a simple index of strain severity. The epidemiological consequences of the uneven distribution of CTV and rapid decline are discussed. 相似文献