Weed Biology and Identification-206
Target students: M.Sc. Students in Weed Science
Lecture:
Dr. Majid AghaAlikhani (Ph.D.)
Academic position :
Associate Prof. of Tarbiat Modares [email protected]
1
Classification of Plants
Plant Kingdom
Flowering Plants
Non-flowering Plants
. 3 groups
FernsMosses Gymnosperms
Non - flowering Plants
Do NOT produce flowers
A plant can be divided into 3 parts
Land Plants - Embryophytes
Liverworts, Hornworts, Mosses
Examples of Mosses
spores
Spore-producing capsule
.No true roots, No vascular tissues (no transport)
Characteristics of Mosses
.Simple stems & leaves
.Have rhizoids for anchorage
.Spores from capsules (wind-dispersal)
.Damp terrestrial land
.Simplest plants
Vascular Plants - Tracheophytes
Lycophytes (Lycopods)
Isoetes orcuttii
Selaginella apoda Selaginella bigelovii
Vascular Plants
Equisetophytes (Equisetales): Equisetum
Equisetum arvense
Common HorsetailEquisetum spp.
Scouring-Rush
Vascular Plants
Ophioglossoid Ferns (Ophioglossales)
Ophioglossum californicum
Calif. Adder’s Tongue
Vascular Plants - Tracheophytes
Psilotophytes (incl. Psilotum, Tmesipteris)
Vascular Plants - Tracheophytes
Marratiophytes
Vascular Plants
Leptosporangiate Ferns
(Polypodiales)
Polypodium californicum
California PolypodyDryopteris arguta
Coastal Wood Fern
underground stem
root
A leaf (finely divided into small parts)
.roots, feathery leaves & underground stems
Characteristics of Ferns
.have vascular tissues (transport & support)
.Damp & shady places
.Spore-producing organ on the underside of leaves (reproduction)
Seed Plants: Gymnosperms
Cycads Ginkgo
Cycas circinalis Ginkgo biloba
Abies concolor
White Fir
Pinus torreyana
Torrey Pine
Cupressus forbesii
Tecate Cypress
Conifers
needle-shaped leaves
Male cones (in clusters)
Female cones (scattered)
.roots, woody stems
Characteristics of Gymnosperms
.needle-shaped leaves
.tall evergreen trees
.cones with reproductive structures
.dry places
.vascular tissues (transport)
.naked seeds in female cones
Ephedra spp. Mormon Tea
Gnetales
Welwitschia mirabilis
Seed Plants: Angiosperms - Flowering Plants
. 2 groups
Monocotyledons Dicotyledons
Flowering Plants
. roots, stems, leaves
. vascular tissues (transport)
. flowers, fruits (contain seeds)
parallel venation
Monocots
1 cotyledon
floral parts in 3’s(often)
radicle
epicotyl
hypocotyl
1 cotyledon
embryo
coleorhiza
coleoptile
radicle
epicotyl
1 cotyledon
MONOCOTS
Monocotyledons
Parallel veins
. one seed-leaf
Characteristics of Monocotyledons
leaves have parallel veins
. herbaceous plants
. e.g. grass, maize
Dicotyledons
Veins in network
net venation
Eudicots
2 cotyledons
floral parts in 4’s or 5’s(often)
embryo
seed coat
radicle
epicotyl
hypocotyl
2 cotyledons
endosperm
NON-MONOCOT
{
. two seed-leaves
Characteristics of Dicotyledons
. leaves have veins in network
. e.g. trees, sunflower, rose
Plant ClassificationNon-flowering
Plants
Flowering
Spore-bearing
Naked seeds
No roots
with roots
Mosses Ferns
Gymnosperms
1 seed-leaf
2 seed-leaves
Monocots Dicots
