EEB 304 Lecture 3 – Plant Manipulation and Naming

Optional Assignment

List the continents that would be included under the designations “Old World” and “New World”

Return as hard copy or send by e-mail to receive credit

Due Thursday 1/20/11

“What’s in a name? That which we call a rose

By any other name would smell so sweet.”

“What’s in a name? That which we call a rose

By any other name would smell so sweet.”

Shakespeare, “Romeo and Juliet”

Mystery Plant - This plant is a native of the Old World that has multiple uses

Mystery Plant - This plant is a native of the Old World that has multiple uses

- It is used for its fibers to make rope, fishnets, clothing, etc.

Mystery Plant - This plant is a native of the Old World that has multiple uses

- It is used for its fibers to make rope, fishnets, clothing, etc.

- Because its importance as a source of fibers, it was widely planted in the U.S. midwest during World War II

Mystery Plant - This plant is a native of the Old World that has multiple uses

- It is used for its fibers to make rope, fishnets, clothing, etc.

- Because its importance as a source of fibers, it was widely planted in the U.S. midwest during World War II

- It is also the source of a psychoactive drug, which has led to its possession and using being considered a criminal offense in the U.S.

Mystery Plant - This plant is a native of the Old World that has multiple uses

- It is used for its fibers to make rope, fishnets, clothing, etc.

- Because its importance as a source of fibers, it was widely planted in the U.S. midwest during World War II

- It is also the source of a psychoactive drug, which has led to its possession and using being considered a criminal offense in the U.S.

- In the 1960s and 1970s, court battles ranged that centered on the name for the plant, with both prosecution and defense enlisting the services of expert botanists.

Mystery Plant - This plant is a native of the Old World that has multiple uses

- It is used for its fibers to make rope, fishnets, clothing, etc.

- Because its importance as a source of fibers, it was widely planted in the U.S. midwest during World War II

- It is also the source of a psychoactive drug, which has led to its possession and using being considered a criminal offense in the U.S.

- In the 1960s and 1970s, court battles ranged that centered on the name for the plant, with both prosecution and defense enlisting the services of expert botanists.

1. What is the plant?

2. Why was there a dispute about its name?

3. What was the legal resolution of the issue about its name?

Quiz

1. A scientific name for an organism consists of how many words? In what language is it written?

2. What is polyploidy? How common is it in plants? Give an example of a crop species that is polyploid.

Plant Manipulation – the Raw Material

Flowering Plants – ca 300,000 species

Plant Manipulation – the Raw Material

Flowering Plants – ca 300,000 species

Plants eaten regularly by people – ca 2,500 species

Plant Manipulation – the Raw Material

Flowering Plants – ca 300,000 species

Plants eaten regularly by people – ca 2,500 species

Plants in World Commerce – ca 150 species

Plant Manipulation – the Raw Material

Flowering Plants – ca 300,000 species

Plants eaten regularly by people – ca 2,500 species

Plants in World Commerce – ca 150 species

Major Economic Importance – ca 20 species

Plant Manipulation – the Raw Material

Flowering Plants – ca 300,000 species

Plants eaten regularly by people – ca 2,500 species

Plants in World Commerce – ca 150 species

Major Economic Importance – ca 20 species

Crops recently domesticated – 0 species

Plant Manipulation – the Raw Material

Flowering Plants – ca 300,000 species

Plants eaten regularly by people – ca 2,500 species

Plants in World Commerce – ca 150 species

Major Economic Importance – ca 20 species

Crops recently domesticated – 0 species

Crops of Major Economic Importance

Crops of Major Economic Importance

Wheat, Rice, Maize (Corn), and Potatoes – the Big 4

Traditional Methods of Plant Manipulation

- Selection

- Polyploidy

- Asexual Reproduction (=cloning)

- Inbreeding

Variation and Selection

Keystone of Evolutionary Theory – “Selection of the Fittest”

Natural Selection – wild populations

Variation and Selection

Keystone of Evolutionary Theory – “Selection of the Fittest”

Natural Selection – wild populations

Artificial Selection – when done by people

Variation and Selection

Keystone of Evolutionary Theory – “Selection of the Fittest”

Natural Selection – wild populations

Artificial Selection – when done by people

Note: For selection to work, there must be variation, and it must be heritable

- mutations (natural and induced)

Variation and Selection

Keystone of Evolutionary Theory – “Selection of the Fittest”

Natural Selection – wild populations

Artificial Selection – when done by people

Note: For selection to work, there must be variation, and it must be heritable

- mutations (natural and induced)

- geographic variation

Artificial Selection in Cole Crops

Polyploidy

Eukaryotic organisms, typically 2 sets of chromosomes/nucleus

= diploid

Polyploidy

Eukaryotic organisms, typically 2 sets of chromosomes/nucleus

= diploid

Gametes – have one set of chromosomes/nucleus (result of meiosis)

= haploid

Polyploidy

Eukaryotic organisms, typically 2 sets of chromosomes/nucleus

= diploid

Gametes – have one set of chromosomes/nucleus (result of meiosis)

= haploid

Some plants – cells have >2 sets of chromosomes = polyploid

triploid = 3 sets

Polyploidy

Eukaryotic organisms, typically 2 sets of chromosomes/nucleus

= diploid

Gametes – have one set of chromosomes/nucleus (result of meiosis)

= haploid

Some plants – cells have >2 sets of chromosomes = polyploid

triploid = 3 sets

tetraploid = 4 sets

Polyploidy

Eukaryotic organisms, typically 2 sets of chromosomes/nucleus

= diploid

Gametes – have one set of chromosomes/nucleus (result of meiosis)

= haploid

Some plants – cells have >2 sets of chromosomes = polyploid

triploid = 3 sets

tetraploid = 4 sets

pentaploid = 5 sets

hexaploid = 6 sets

etc.

Polyploidy continued

“Odd” polyploids (3x, 5x, 7x) – usually sterile

- advantage for seedless fruit

Polyploidy continued

“Odd” polyploids (3x, 5x, 7x) – usually sterile

- advantage for seedless fruit

“Even” polyploids (4x, 6x, 8x) – often fertile

- organs can be larger, including fruits, seeds

Polyploidy continued

“Odd” polyploids (3x, 5x, 7x) – usually sterile

- advantage for seedless fruit

“Even” polyploids (4x, 6x, 8x) – often fertile

- organs can be larger, including fruits, seeds

- heterosis fixed

Polyploidy continued

“Odd” polyploids (3x, 5x, 7x) – usually sterile

- advantage for seedless fruit

“Even” polyploids (4x, 6x, 8x) – often fertile

- organs can be larger, including fruits, seeds

- heterosis fixed

Many crop plants are polyploid – see text, Table 1.1

Coffee, Cotton, Potato, Strawberry, Sugar cane, Tobacco, Wheat

Polyploidy continued

“Odd” polyploids (3x, 5x, 7x) – usually sterile

- advantage for seedless fruit

“Even” polyploids (4x, 6x, 8x) – often fertile

- organs can be larger, including fruits, seeds

- heterosis fixed

Many crop plants are polyploid – see text, Table 1.1

Coffee, Cotton, Potato, Strawberry, Sugar cane, Tobacco, Wheat

Even some crops that appear to be diploid are ancient polyploids:

Corn, sunflower

Polyploidy continued

“Odd” polyploids (3x, 5x, 7x) – usually sterile

- advantage for seedless fruit

“Even” polyploids (4x, 6x, 8x) – often fertile

- organs can be larger, including fruits, seeds

- heterosis fixed

Many crop plants are polyploid – see text, Table 1.1

Coffee, Cotton, Potato, Strawberry, Sugar cane, Tobacco, Wheat

Even some crops that appear to be diploid are ancient polyploids:

Corn, sunflower “Whole Genome Duplication” - WGD

Hybrid sterility

Polyploidy can overcome hybrid sterility

Inbreeding

Most Plants are Outcrossing – gametes from different individuals

Inbreeding

Most Plants are Outcrossing – gametes from different individuals

Some plants, particularly weeds and crop plants, are inbreeding

- self-fertilization

- self-compatibility

Inbreeding

Most Plants are Outcrossing – gametes from different individuals

Some plants, particularly weeds and crop plants, are inbreeding

- self-fertilization

- self-compatibility

Forced Inbreeding:

- increased homozygosity

- inbreeding depression

Inbreeding

Most Plants are Outcrossing – gametes from different individuals

Some plants, particularly weeds and crop plants, are inbreeding

- self-fertilization

- self-compatibility

Forced Inbreeding:

- increased homozygosity

- inbreeding depression

Crossing between homozygous lines Heterosis (hybrid vigor)

- uniformity

Inbreeding

Most Plants are Outcrossing – gametes from different individuals

Some plants, particularly weeds and crop plants, are inbreeding

- self-fertilization

- self-compatibility

Forced Inbreeding:

- increased homozygosity

- inbreeding depression

Crossing between homozygous lines Heterosis (hybrid vigor)

- uniformity

- need to produce new seed each year

Asexual Reproduction

Asexual Reproduction new plants identical to parent (clones)

Asexual Reproduction

Asexual Reproduction new plants identical to parent (clones)

Applications of Asexual Reproduction:

- vegetative propagation (cuttings, rhizome pieces etc.)

- grafting

Naming of Plants

Scientific Hierarchy of Classification (See Table 1.5, page 35)

Kingdom Phyta “plants”

Division Anthophyta “flowering plants”

Class Magnoliopsida “dicots”

Order Fabales “bean order”

Family Fabaceae “bean family”

Genus Phaseolus* “beans”

Species P. vulgaris* “common bean”

*Name written in Latin

Species Names – Binomial Nomenclature

Prior to Linnaeus – use of Phrase Names

Species Names – Binomial Nomenclature

Prior to Linnaeus – use of Phrase Names

Linnaeus – each species called by genus name + species epithet = binomial

Species Names – Binomial Nomenclature

Prior to Linnaeus – use of Phrase Names

Linnaeus – each species called by genus name + species epithet = binomial

Species – only category that is thought to be discrete, objective

Species Names – Binomial Nomenclature

Prior to Linnaeus – use of Phrase Names

Linnaeus – each species called by genus name + species epithet = binomial

Species – only category that is thought to be discrete, objective

Species name – consists of genus + species epithet, written in Latin

Principles of Botanical Names1. Publication – name must be properly published according to

rules of International Code of Botanical Nomenclature

Principles of Botanical Names1. Publication – name must be properly published according to

rules of International Code of Botanical Nomenclature

2. Type method – each name is associated with a physical plant specimen (= type specimen)

Principles of Botanical Names1. Publication – name must be properly published according to

rules of International Code of Botanical Nomenclature

2. Type method – each name is associated with a physical plant specimen (= type specimen)

3. Priority – Oldest properly published name is correct one

Example – Rule of Priority leads to Change in Plant Name

Wyethia trilobata

Example – Rule of Priority leads to Change in Plant Name

Wyethia trilobata

Complaya trilobata

Complaya – published in 1991

Example – Rule of Priority leads to Change in Plant Name

Wyethia trilobata

Complaya trilobata

Thelechitonia trilobata

Complaya – published in 1991

Thelechitonia – published in 1954

Example – Rule of Priority leads to Change in Plant Name

Wyethia trilobata

Complaya trilobata

Thelechitonia trilobata

Sphagneticola trilobata

Complaya – published in 1991

Thelechitonia – published in 1954

Sphagneticola – published in 1900

Chrysanthemum s.l. (ca 100 species)

“Ox-eye Daisy”

“Mums”

Example – Change in Circumscription of Genus leads to changes in plant names

Chrysanthemum s.s. (3 species)

Leucanthemum

Dendranthemum

Example – Change in Circumscription of Genus leads to changes in plant names

Categories within SpeciesVariation also occurs within species, in some cases it is significant

enough to be recognized by scientists:

1. Wild species – varieties or subspecies. Both names are written in Latin and follow similar rules as for species names

Used to designate geographic races or morphologically distinct populations adapted to particular local ecological conditions

Cultivar Names2. Variation within cultivated plants

- “variety” – widely (and still) used

- cultivar (cultivated variety)

Used to denote an assemblage of cultivated plants that is clearly distinguished by some character(s) and that following reproduction retains its distinguishing character(s)

Cultivar name is written in any language except for Latin

Cultivar name can be combined with a generic, specific, or common name:

Citrullus cv. Crimson Sweet;

watermelon cv. Crimson Sweet;

Citrullus lanatus cv. Crimson Sweet

A Rose by Any Other Name …?Cannabis sativa and the law

Most Botanists:

Cannabis has 1 species, C. sativa

A Rose by Any Other Name …?Cannabis sativa and the law

Most Botanists:

Cannabis has 1 species, C. sativa

Some botanists recognize 3 species:

C. sativa (hemp, cultivated for rope)

C. ruderalis (wild form, weed)

C. indica (high THC-form)

A Rose by Any Other Name …?Cannabis sativa and the law

Most Botanists:

Cannabis has 1 species, C. sativa

Some botanists recognize 3 species:

C. sativa (hemp, cultivated for rope)

C. ruderalis (wild form, weed)

C. indica (high THC-form)

Laws: originally proscribe marijuana (C. sativa) argument that defendant not literally breaking law

A Rose by Any Other Name …?Cannabis sativa and the law

Most Botanists:

Cannabis has 1 species, C. sativa

Some botanists recognize 3 species:

C. sativa (hemp, cultivated for rope)

C. ruderalis (wild form, weed)

C. indica (high THC-form)

Laws: originally proscribe marijuana (C. sativa) argument that defendant not literally breaking law

Eventual resolution: looked past botanical “semantics” – illegal regardless of what it is called by scientists

Tuesday Lecture – Origins of Agriculture

Read: Chapter 2