Nicotiana tabacumNicotiana tabacumFalak BhattFalak Bhatt

IB 423IB 423May 4, 2005May 4, 2005

www.plantoftheweek.org

ClassificationClassificationDivision MagnoliophytaDivision Magnoliophyta

Class: MagnoliopsidaClass: MagnoliopsidaOrder: SolanalesOrder: Solanales

Family: SolanaceaeFamily: Solanaceae Genus: Genus: NicotianaNicotiana

DicotDicot

http://www.landlfinecigars.com

HistoryHistory Indigenous to North and South Indigenous to North and South

America America 1 BCE: Experts believe American 1 BCE: Experts believe American

inhabitants have begun finding ways inhabitants have begun finding ways to use tobacco, including smoking and to use tobacco, including smoking and chewing chewing

Native Americans smoked before Native Americans smoked before Europeans arrived in America, gave Europeans arrived in America, gave dried leaved as gift to Columbusdried leaved as gift to Columbus

Settlers brought habit back to EuropeSettlers brought habit back to Europe U.S. early colonies made most of U.S. early colonies made most of

internal revenue from tax of tobacco internal revenue from tax of tobacco exportexport

www.tobacco.org

http://www.research.att.com

RootRoot Dicot-Open Root System, FibrousDicot-Open Root System, Fibrous

Columella

Rhizodermis

Root Hair (w/ trichoblast)

Root Cap

Apical Meristem

Root tip 10x-TOL B

RootRoot•Tetrarch development

Phloem

Xylem

Pericycle

Root xs 20x Phloro.

Root: Secondary GrowthRoot: Secondary Growth

Primary Xylem

Secondary Xylem

Ray

Root xs 4x TOL B

Root xs 10x TOL B

RootRoot

Vascular Tissue

Trichome

Whole root 10x TOL B

StemStem•Bicollateral phloem

•Continuous vascular tissue

External Phloem

Internal Phloem

Xylem

Pith

Cortex- Parenchyma

Vascular Cambium

Stem xs 10x

Crang and Vassilyev

StemStem•Multicellular, uniseriate trichomes

Epidermis

Trichomes

Stem xs 10x

Stem xs 20x

Next up…LeavesNext up…Leaves

•Reticulate (netted) venation-Dicot

•Trichomes

Palisade Mesophyll

Spongy Mesophyll

•Bifacial

http://www.botgard.ucla.edu

Leaf xs 10x

LeavesLeaves

•Amphistomatic

•Simple

•Anomocytic stomatal arrangement

Adaxial Abaxial

Leaf peel 20x Leaf peel 20x

LeavesLeaves•Major Leaf Vein…Bicollateral view

Phloem

Xylem

Vascular Cambium

Phloem

Leaves: Gap and TraceLeaves: Gap and Trace

Leaf gap

Leaf trace

Outer endodermis

Inner endodermis

Stem xs 10x

Reproductive StructuresReproductive Structures

Sepal

Ovule Locule

Locules

Ovary Wall

Ovules

Optional Features

Bud xs

Ovary longitudnal

Reproductive StructuresReproductive Structures

Testa

•The embryo is surrounded by three to five layers of rather thick-walled endosperm cells in the mature seed. The periphery of the endosperm is pressed against the thin seed coat (testa), consisting of cutinized and lignified dead cells

Endosperm

Bud xs 10x

Reproductive StructuresReproductive Structures

Testa (seed coat)

Endosperm

Radicle

CotyledonsEMBRYO

http://www.leubner.ch/anatomy.html#

Secretory Structures & NicotineSecretory Structures & Nicotine•Tobacco leaves have 2 types of Trichomes

•Short stalked

•Nicotine

•Organic alkaloid and powerful neurotoxin

•Biosynthesis in roots, accumulate in leaves

•Long stalked

•Diterpeniods

Glover 2000

ReferencesReferences Crang, R & Vassilyev A. Crang, R & Vassilyev A. Plant AnatomyPlant Anatomy CD. 2003. CD. 2003. http://www.botany.org/ajb/00029122_di001557.htmlhttp://www.botany.org/ajb/00029122_di001557.html http://images.botany.org/set-14/http://images.botany.org/set-14/ http://www.leubner.ch/anatomy.html#http://www.leubner.ch/anatomy.html# www.tobacco.orgwww.tobacco.org www.plantoftheweek.orgwww.plantoftheweek.org http://www.landlfinecigars.com http://www.research.att.com http://www.botgard.ucla.edu Glover, Beverley J. Differentiation in plant epidermal cells.

Journal of Experimental Botany. Vol. 51, No. 344, pg 497-505, March 2000.