79 research outputs found
A revision of chestnut-leaved oak (Quercus castaneifolia C. A. Mey.; Fagaceae) in Hyrcanian Forests of Iran
Chestnut-leaved oak (Quercus castaneifolia C. A. Mey) is one of the most important native oaks of Iran
distributed in the Hyrcanian Forests. The pure and mixed stands of it cover about 6.5% of these forests.
The species represents morphological variations which have resulted in the description of several
infraspecific taxa by different authors. Eight taxa were recognized as subspecies and varieties of Q.
castaneifolia. In this survey, a set of quantitative and qualitative micro-morphological characteristics such
as type of trichome, number and length of trichome rays, type of epicuticular waxes, type and shape of
stomata, shape and sculptural features of pollen exine were studied using light microscopy and scanning
electron microscopy. These characters were analyzed by the discriminant analysis method and combined
with the macromorphological characters to designate the variation within the species and to evaluate the
existing infraspecific taxa. Based on our results, the studied taxa are defined into four infraspecific taxa as
follows: Q. castaneifolia subsp. castaneifolia var. castaneifolia, Q. castaneifolia subsp. castaneifolia var. minuta, Q.
castaneifolia subsp. aitchisoniana, Q. castaneifolia subsp. undulate. The studied characteristics showed to be
diagnostic for identification of the infraspecific taxa
Shift of the western boundary of the distribution area of Micromeria cristata (Hampe) Griseb. and Steptorhamphus tuberosus (Jacq.) Grossh.
During field investigations of Mt Rumija, two new taxa for the flora of Montenegro were recorded: Micromeria cristata (Hampe) Griseb. and Steptorhamphus tuberosus (Jacq.) Grossh. From the phytogeographic point of view these data indicate a change in the distribution area of both taxa, which have shifted to the west. Ashort overview of the taxonomic treatment of both genera is given
Phytochemistry and bioactivity of aromatic and medicinal plants from the genus Agastache (Lamiaceae)
Chemical Composition and Antibacterial Activity of Essential Oils of Various Plant Organs of Wild Growing Nepeta cataria
Taxonomic revision of the Quercus brantii complex (fagaceae) in Iran with emphasis on leaf and pollen micromorphology
Micromorphological characters of leaves and pollen grains of the Quercus brantii complex (including seven species and five varieties), as the main species in the Zagros Forests of Iran, were studied by scanning electron microscopy. In order to define the diagnostic value of leaves and pollen grains for species delimitation, multivariate discriminant analysis was applied to micromorphological quantitative features. The results were combined with qualitative characters of pollen grains to separate the examined taxa. Five taxa were confirmed within this complex: Q. brantii var. brantii, Q. brantii var. belangeri, Q. persica, Q. saii and Q. ungeri. The macro- and micromorphological characters of the accepted taxa and their geographical distribution were described. Based on the present results, leaf epidermal characteristics and pollen features are useful taxonomic characters that can help to delimit different taxa within the Q. brantii complex in Iran
Analysis of flat terrain for the Atlas robot
This paper gives a description of an approach to analyze the sensor information of the surroundings to select places where the foot of a humanoid can be placed. This will allow apply such robot in a rescue scenario, as foreseen in the DARPA Robotics Challenge, where a robot is forced to traverse difficult terrain
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