J. Johnston et al., IRIDOID GLYCOSIDE AND ALLOZYME VARIATION WITHIN AND AMONG POPULATIONSOF PLANTAGO-RHODOSPERMA DECNE. (PLANTAGINACEAE), Biochemical systematics and ecology, 25(7), 1997, pp. 581-590
To compare and contrast the inter-and intra-population variation in Pl
antago rhodosperma, individuals from four populations in Kansas (Russe
ll, Woodston, Stockton A and Stockton B) were sampled. The following f
ive characteristics were compared: (1) size of the plants, using area
of the largest leaf as an index, (2) number of trichomes on the upper
and lower leaf surfaces, (3) iridoid glycoside concentration of leaves
and scapes, (4) leaf nitrogen concentration, and (5) allozyme variabi
lity. The Russell and Woodston populations were significantly smaller
than those from Stockton A and B, and had greater trichome densities o
n the upper leaf surface. The Stockton B population had significantly
more aucubin in the leaves than the other populations sampled. However
, the aucubin concentration in the scapes did not differ among populat
ions. The Stockton A and B populations had significantly higher leaf n
itrogen concentrations than Russell, but Woodston was not significantl
y different from either of the other two. There was little inter-popul
ational allozyme variation, although the Russell population showed all
ozyme variability among individuals for the enzyme PGI. The allozyme d
ata suggest that P. rhodosperma is an allopolyploid. (C) 1997 Elsevier
Science Ltd.