TITLE:
Macro and Micromorphological Studies on Seven Species of Heliotropium L. (Boraginaceae Juss.) in South West of Saudi Arabia
AUTHORS:
Wael Taha Kasem
KEYWORDS:
Heliotropium L., Leaf Venation, Stomata, Trichomes, Pollen Grains, Stem Anatomy
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.6 No.9,
June
9,
2015
ABSTRACT: Genus Heliotropium L. (Heliotropiaceae) in
south west of Saudi Arabia has been studied; seven species of H. arbainense Fresen, H. longiflorum (D.C.) Jauber & Spach, H. petrocarpum Hockst & Steud, H. strigosium Willd, H. zeylanicum Lam., H. jizanense Al-Turki and H.
lasiocarpum Fisch were collected, recognized, typed and nomenclatured. The
most valuable characters were those of macro and distinct micromorphological
data such as stomata, hairs, pollen grains and stem anatomy. Light microscopy
has been used in these studies. From the obtained results, trichomes and pollen
grains data in addition to stem anatomy indicated good taxonomic tools to
differentiate between species of this genus. Different traditional measurements
were strikingly also helpful for the discrimination of species. H. longiflorum was characterized by
distinctive data such as prominent anatomical information, P/E (1.8 μm) in
addition to presence of spindle hair which in turn can
be separated as a taxonomic level. Also, the results revealed
a complete affinity between the two species of H. jizanense and H.
lasiocarpum. An artificial key is provided for the differentiation between
the studied species.