Tuesday Lecture – Ornamental Plants Reading: Textbook, Chapter 17
Mar 31, 2015
Tuesday Lecture – Ornamental Plants
Reading: Textbook, Chapter 17
Quiz
Quiz
1.Describe a factor that could result in a plant having a leaf that has a coloration other than solid green.
2.Describe a feature of the UTIA Gardens that you particularly liked.
Naming OrnamentalsDifficulties introduced by the nature of ornamentals:
often hybrids
- many are sterile, propagated vegetatively
- mutants with striking features – propagated vegetatively to retain features
- marketing
International Code of Horticultural Nomenclature – sets of rules governing assignment of cultivar names
Some widely grown plants may have a registry of cultivar names
Naming OrnamentalsDifficulties introduced by the nature of ornamentals:
- often hybrids
- many are sterile, propagated vegetatively
- mutants with striking features – propagated vegetatively to retain features
- marketing
International Code of Horticultural Nomenclature – sets of rules governing assignment of cultivar names
Some widely grown plants may have a registry of cultivar names
Naming OrnamentalsDifficulties introduced by the nature of ornamentals:
- often hybrids
- many are sterile, propagated vegetatively
- mutants with striking features – propagated vegetatively to retain features
- marketing
International Code of Horticultural Nomenclature – sets of rules governing assignment of cultivar names
Some widely grown plants may have a registry of cultivar names
Naming OrnamentalsDifficulties introduced by the nature of ornamentals:
- often hybrids
- many are sterile, propagated vegetatively
- mutants with striking features – propagated vegetatively to retain features
-marketing
International Code of Horticultural Nomenclature – sets of rules governing assignment of cultivar names
Some widely grown plants may have a registry of cultivar names
Naming OrnamentalsDifficulties introduced by the nature of ornamentals:
- often hybrids
- many are sterile, propagated vegetatively
- mutants with striking features – propagated vegetatively to retain features
- marketing
International Code of Horticultural Nomenclature – sets of rules governing assignment of cultivar names
Some widely grown plants may have a registry of cultivar names
Naming OrnamentalsDifficulties introduced by the nature of ornamentals:
- often hybrids
- many are sterile, propagated vegetatively
- mutants with striking features – propagated vegetatively to retain features
- marketing
International Code of Horticultural Nomenclature – sets of rules governing assignment of cultivar names
Some widely grown plants may have a registry of cultivar names
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
Types of Ornamentals
1. Nursery Crops – planted outside
- trees/shrubs; turf; ground covers; bedding plants
Types of Ornamentals
1. Nursery Crops – planted outside
- trees/shrubs; turf; ground covers; bedding plants
2. Florist Crops – grown for cut flowers or foliage
- increased worldwide: $12.5 billion (1985) $25 billion (2009)
Types of Ornamentals
1. Nursery Crops – planted outside
- trees/shrubs; turf; ground covers; bedding plants
2. Florist Crops – grown for cut flowers or foliage
- increased worldwide: $12.5 billion (1985) $25 billion (2009)
US – dipped from 4.2 billion (2007) to 3.8 billion (2009)
Types of Ornamentals
1. Nursery Crops – planted outside
- trees/shrubs; turf; ground covers; bedding plants
2. Florist Crops – grown for cut flowers or foliage
- increased worldwide: $12.5 billion (1985) $25 billion (2009)
3. Houseplants – sold for growing indoors
- plants must survive in harsh environment
Asteraceae – The Ornamental Family
- Ageratum
- Aster
- Black-eyed Susan
- Cornflower
- Dahlia
- Daisy
- Marigold
- Chrysanthemum (Dendranthemum)
- Sunflower
- Zinnia
Topped by a Head
Topped by a Head
Variations on a ThemeDandelion – all rays
Variations on a ThemeDandelion – all rays
Pussytoes – all disk
Variations on a ThemeDandelion – all rays Cornflower – All
Disk/outer ones larger Pussytoes – all disk
“Doubled” Heads
Single (“Old-Fashioned”) Zinnia
“Doubled” Heads
Single (“Old-Fashioned”) Zinnia Double Zinnia
Another Double
Single Marigold Double Marigold
Marigold – Tagetes - native to Mexico
Daisy – Inspiration for “Big Orange”
Daisy – Inspiration for “Big Orange”
UT Uniform Color – traces origin to center of daisy heads
Daisy – Inspiration for “Big Orange”
Shasta Daisy – tetraploid selection of Luther Burbank
UT Uniform Color – traces origin to center of daisy heads
Polyploidy – Breeding Tool
Daylilies – Hemerocallis fulva
Diploid Tetraploid
Polyploidy: >2 sets of
chromosomes
1. Determinate organs will be larger
2. Stabilizes (and sometimes makes fertile) hybrids
3. Odd polyploids often sterile:
- no messy seeds
- no need to “deadhead”
Flowers - Variations
Showy structure is not part of flower
bract
dogwood
poinsettia
More Flower Variations
More Flower Variations“doubled” flowers – stamen primordia petals
Pink Carnation
Araceae – the Houseplant FamilyMany Aroids – tropical epiphytes – habitat similar to house/apartment
Spathiphyllum – the Mall PlantNote: inflorescence is spathe + spadix
Amorphophallus – a Giant Aroid
1.37 m tall
Amorphophallus titanum
Geneticist Huge de Vries, one of the rediscoverers of Mendel’s Laws, provides scale for an inflorescence of the “Voodoo Plant”
Amorphophallus – a Giant Aroid
1.37 m tall
An Aroid Gallery
How Dumb Cane Got Its Name
How Dumb Cane Got Its Name
Calcium oxalate – characteristic crystalline inclusions (raphides) in Araceae extreme irritation of mucous membranes
Can lead to fatal swelling of passages to lungs
Commonly Ingested AroidsFrom List of “Top 20 Ingested Plants” Reported to Poison Control
Centers in U.S.:
2. Philodendron
4. Spathiphyllum
6. Dieffenbachia
10. Epipremnum (Pothos)
Treatment: Symptomatic and Supportive – remove residue from mouth; provide liquids; monitor breathing (major danger is suffocation is swelling is severe)
Invasive Plants – The Dark Side of Ornamentals
Invasive Plants = “Biological Pollution”
“Rule of 10’s”:
Invasive Plants – The Dark Side of Ornamentals
Invasive Plants = “Biological Pollution”
“Rule of 10’s”:
For every 10 plants introduced, 1 will become established
Invasive Plants – The Dark Side of Ornamentals
Invasive Plants = “Biological Pollution”
“Rule of 10’s”:
For every 10 plants introduced, 1 will become established
For every 10 established, 1 will become invasive
1 in 100 introductions becomes invasive
Invasive Plants – The Dark Side of Ornamentals
Invasive Plants = “Biological Pollution”
“Rule of 10’s”:
For every 10 plants introduced, 1 will become established
For every 10 established, 1 will become invasive
1 in 100 introductions becomes invasive
Often a long lag time, introduction problematic invader
“First it sleeps, then it creeps, then it leaps …”
Invasive Plants – The Dark Side of Ornamentals
Invasive Plants = “Biological Pollution”
“Rule of 10’s”:
For every 10 plants introduced, 1 will become established
For every 10 established, 1 will become invasive
1 in 100 introductions becomes invasive
Often a long lag time, introduction problematic invader
How to Predict Invasiveness?
- only clear guide, if invasive in other areas
Dandelion - Invader
Taraxacum officinale (“of the shops”)
Dandelion - Invader
Taraxacum officinale (“of the shops”)
Dandelion (“dents du lion” = lion’s tooth, from leaves)
Dandelion - Invader
Taraxacum officinale (“of the shops”)
Dandelion (“dents du lion” = lion’s tooth, from leaves)
Asteraceae – all ray flowers
Introduced by Pilgrims – used as spring potherb
Dandelion - Invader
Taraxacum officinale (“of the shops”)
Dandelion (“dents du lion” = lion’s tooth, from leaves)
Asteraceae – all ray flowers
Introduced by Pilgrims – used as spring potherb
Flowers – produce abundant nectar sugar source to produce wine
Dandelion - Invader
Taraxacum officinale (“of the shops”)
Dandelion (“dents du lion” = lion’s tooth, from leaves)
Asteraceae – all ray flowers
Introduced by Pilgrims – used as spring potherb
Flowers – produce abundant nectar sugar source to produce wine
Apomictic – seeds produced without fertilization clones of parent
Will mature its seed even if uprooted
Tennessee Invaders
TN-EPPC (Tennessee Exotic Pest Plant Council) – List
Trees: Mimosa (Albizzia); Princess Tree (Paulownia); Tree-of-Heaven (Ailanthus)
Shrubs: Autumn Olive (Eleagnus); Bush Honeysuckles (Lonicera); Japanese Barberry (Berberis); Multiflora Rose (Rosa); Privet (Ligustrum)
Herbs: Purple loosestrife (Lythrum); others
Vines: Euonymus; Japanese honeysuckle (Lonicera); Japanese wisteria; Kudzu (Peuraria); Oriental Bittersweet (Celastrus)
Native Plants – A Great Resource
Answer to Invaders = use native plants
See Box 17.2, p. 429 Wildscaping
Opportunity: provide plants for revegetation, environmental restoration projects
Thursday, Genetically Modified (GM) Plants