TABLE 1

Comparison of morphological traits among wild H. annuus ssp. annuus, H. annuus ssp. texanus, and H. debilis ssp. cucumerifolius

H. annuus ssp.
annuus
H. annuus ssp.
texanus
H. debilis ssp.
cucumerifolius
Stem specklingNoneIntermediateHeavy
Leaf serrationSerrateDeeply irregularJagged
Head no.FewIntermediateMany
Ray flower no.21-3519-2513-18
Ligule length (l)3.0-5.0 cm2.4-3.2 cm1.2-2.3 cm
Ligule width (w)1.0-1.5 cm0.8-1.2 cm0.5-1.2 cm
Ligule shape (l/w)3.0-3.82.7-3.11.9-2.1
Disk diameter3.0-5.0 cm2.1-3.0 cm1.0-2.2 cm
Phyllary length (l)1.0-1.5 cm1.0-1.5 cm1.0-1.1 cm
Phyllary width (w)0.4-0.7 cm0.35-0.6 cm0.15-0.3 cm
Phyllary shape (l/w)2.0-3.02.5-4.05.0-8.3
Phyllary pubescenceHirsuteSparingly hispidGlabrous or sparingly hispid
Achene length (l)0.4-0.7 cm0.33-0.5 cm0.32-0.4 cm
Achene width (w)0.25-0.3 cm0.2-0.25 cm0.12-0.18 cm
Achene shape (l/w)1.7-2.41.6-2.31.7-3.0
  • Data were obtained from Heiser (1951, 1954), Heiser et al. (1969), and from personal observations of greenhouse-grown plants.