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10/2/2014
1
Introduction to Botany
Jan Zientek
Senior Program Coordinator
Cooperative Extension of Essex County
Caveat
• All misrepresentations of the plant world are my fault
Basic Botany
• The study of the growth, structure and function of plants
BOTANY
• Evolution• Taxonomy• Plant morphology• Plant physiology and cell biology• Plant reproduction• Plant hormones and growth regulators
Bamboo Orchid Arundina graminifolia
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Poor Man’s Umbrella
Gunnera insignis
Common Name vs Scientific Name
• Maybe local name
• General• Universally recognized
• Specific
Foxglove Digitalis purpurea
Common Name vs Scientific Name
Fire bush
Hamelia patens
Scarlet bush
Texas firecracker
Corail (or is it Koray?)
Ix-canan
Hummingbird bush
Polly red head
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Rules for Writing Scientific Names
• The genus and species are written in italics or underlined.
• The first letter of the genus name is always capitalized.
• The word designating the species is always written lower case
letters.
Rules for Writing Scientific Names
• Cultivar names are not italicized or underlined
• Cultivar names are surrounded by ‘single quotation marks’
• Species may be abbreviated spp.
Plant Functions
PLANTAE
• Eukaryotic (with a nucleus)
• Cell walls with cellulose
• Food stored as carbohydrate
• Multi-cellular autotrophs
• Chloroplasts (green)
• Non-motile• Several phlyum• Development of
pollen
DOMAINKINGDOM
PHYLUMCLASS
ORDER FAMILY (impress your gardener friends)
must know Genus species
cultivar(impress your gardener friends)
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Cultivar
• The term cultivar is the contraction of two words – cultivated
and variety.
• Cultivars are the product of plant breeding. Species of plants
may have many named cultivars that have distinguishing
characteristics.
Plant phylums (types)
Mosses
Liverworts
Hornworts
Club mosses
Horsetails
Ferns
Cycads
Ginkgoes*
Gnetophytes
Conifers
Until sometime in the 90’s
Ginkgoes were thought to be
related to conifers. Why?
Because botantists
(taxonimists) were ready for a
phylum with one member!
Mosses are non-vascular plants --they cannot transport fluids through their bodies. Instead, they must rely on surrounding moisture to do this job for them.
Plant TypesFerns and allies have a vascular system to transport fluids through their bodies but like the mosses, they reproduce from spores rather than seeds. The main phylum, theFerns (Filicinophyta = Pteridophyta) includes around 12,000 species.
• Monocots: have a single cotyledon (seed leaf), flower parts in multiples of three, parallel venation of leaves, scattered vascular bundles in stems. Around 30,000 plants are classified as monocots including many of the prettiest members of kingdomPlantae: orchids, lilies, irises, palms and even the Bird-of-Paradise plant. The grasses which carpet our lawns and meadows are also monocots.
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Dioscorea sp. (Wild Yam)
A monocot with netted veinationDicots: The vast majority of plants are Dicots. Most trees, shrubs, vines, and flowers belong to this group of around 200,000 species. Most fruits, vegetables and legumes come from this class. They have two cotyledons, flower parts in multiples of 4 or 5, netted veins, and stems which are organized in a ring pattern.
Plants can be classified by the type of their seed structure
–Gymnosperm: “naked seed”
–Angiosperm: seed within a fruiting body
The gymnosperms add the next level of complexity to plant evolution: they reproduce from seeds instead of spores. The seeds, however, are "naked" - not covered by an ovary. Usually, the seed is produced inside a cone-like structure such as a pine cone hence the name "conifer." Some conifers, such as the Yew and Fir, produce their seeds inside a berry-like structure. GinkgoConifers are fairly easy to identify: In addition to the aforementioned cones, these trees and shrubs typically have needle-like, scale-like or awl-like leaves. And they never have flowers.
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•Lifecycles help gardeners distinguish between plants:
•Annuals•Biennials•Perennials
Annuals complete life cycles in one season
Biennials live for 2 years,
flower,
then die
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Perennials live for 3 or more years,flower each year and usually do not die after flowering.
Structures of Plants
RootsStemsLeavesFlowersSeeds
Roots
• Anchor plants
• Absorb
– Oxygen
– Water
– Nutrients
A Brief Note on Nutrition…
• Plants feed through their roots …almost exclusively
• Macronutrients –
• Micronutrients –
Mineral Nutrients
Macronutrient Symbol
• Carbon C
• Oxygen O
• Nitrogen N
Available as
• CO2(carbon dioxide) from
air
• O2 (oxygen gas) and CO2
from the air and in some
of the combined forms
listed below
• NO3 (nitrate salts such as
calcium nitrate or NH4
(ammonium salts, such
as ammonium sulfate
Mineral Nutrients
Macronutrient Symbol
• Phosphorus P
• Potassium K
• Sulfur S
• Calcium Ca
Available as
• PO4 (phosphate salts
such as potassium
phosphate)
• Potassium salts such as
potassium phosphate
• SO4 (sulfate salts such as
magnesium sulfate)
• Calcium salts such as
calcium nitrate
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Mineral Nutrients
Micronutrients Symbol
• Magnesium Mg
• Iron Fe
• Copper Cu
• Zinc Zn
Available as
• Magnesium salts such as
magnesium sulfate
• Iron (ferrous) salts such as
ferrous chloride
• Copper salts such as copper
sulfate
• Zinc salts such as zinc
sulfate
Mineral Nutrients
Micronutrients Symbol
• Manganese Mn
• Molybdenum Mo
• Boron B
Available as
• Manganese salts such as
manganous cholride
• Molybdenum salts such
as potassium molybdate
• Borates such as
potassium borate
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Root cross-section
Examples of Stem Structure Herbaceous monocot and dicot stem
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Leaves
• Are the center of food production in the plant– Photosynthesis and respiration occur there– Leaves are either simple (one blade) or
compound (multiple blades)
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Stomata
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One Plant – Two Distinct Shapes FLOWERS
Flowers
• Are sexual organs• Inflorescence• Perfect flower• Imperfect flower• Monoecious• Dioecious
The Flower
Seeds
• Allows for survival of a species into the next growing season
• Adapted to “recognize” ideal growing conditions• Source of energy for young, emerging plant
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Apical meristem: point of vigorous cell division and growth
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Photosynthesis
• Is the chemical process that creates complex sugars from water, carbon dioxide and sunlight.
• Photosynthesis occurs in the chloroplast• Chlorophyll is the green pigment that allows
photosynthesis to occur.
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RESPIRATIONThe transformation of stored chemical energy to usable
energy for growth and development
C6H12O6 plus O2 6CO2 + 6H2O + energy
TRANSPIRATIONThe uptake and release of liquids and gases,
especially water and CO2, by plants.
Important in the regulation of water within the plant
(wilt, turgor, stomatal activity, etc.)
Hormones
Chemical substances that control patterns of growth and development, and responses to environmental conditions
Influencing Plant Growth
Auxin – phototropism, gravitropism, apical dominance
Gibberellins – increased plant and fruit size
Cytokinins – cell division, sprouting
Dormin – accelerates abscission, promotes dormancy
Ethylene – fruit ripening, senescence
• Gardeners use hormones to induce flowering, fruiting, root cuttings, induce or break dormancy, ripen fruit or seeds, chemically “prune” plants, and control growth.
http://www.5min.com/Video/Plant-
Physiology-Phototropic-Response-
1354341
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References
Biology, by Miller and Levine, Prentice Hall, Upper Saddle River, NJ, 2002
Botany: A Golden Guide, by Alexander, Burnett and Zim,
Golden Press, NY, 1970
Botany for Gardeners, by Capon, Timber Press, Portland, OR, 2005
Horticultural Science, by Jannick, Freeman and Co., San Francisco, CA, 1972
Plant Physiology, by Bidwell, MacMillan Publishing Co., NY, 1979