PB 200 Exam 3

A plant would not be considered transgenic if it were engineered with a DNA fragment from a virus. Select one: True False

False

Best test for eligibility for a mushroom?

know the mushroom well

Metabolism

many are aerobic (require oxgen) or facultative anaerobic (can exist with or without oxygen) - with oxygen: anaerobic respiration - without oxygen: alcoholic fermentation (ex: yeasts) will grow on various substrates, but grow on very specific substrates (ex: some fungi will only grow on particular species of insects); very specific Human disease: ringworm, athletes foot, aspergillosis, candidiassis extreme environments: hot spring, arctic and antarctic

a mycelium is composed of

mats of hyphae

Myxomycota= slime molds

not true fungi - prostista plasmodial slime molds (this is what "the blob" is) - body mass of protoplasm -multinucleate - form sporangia and spores -engulf food like an amoeba (can be as larger than dinner plate) ; seen often on wood chips Cellular slime molds: - spores form small single celled amoebae; - amoebae coalesce into sporangium- spores get released to form single amoebae (form slug looking thing) highly understudied

Overview Plant Propagation

Asexual - Vegetative propagation - Cloning Sexual - Plant Breeding Genetic engineering Selection for desirable traits Traditional techniques millenia old

Recombinant DNA Genetic Engineering

Isolate desirable genes Insert these genes into bacteria Bacterial clone the gene Insert gene into recipient plant - Electroporation: Electrical pulses cause cell to take up DNA - Cell bombardment : Shoot gene-coated pellets into the cell - Agrobacterium tumefaciens: Bacterium that can insert DNA into host plant Recipient cell incorporates transferred DNA

Division of Perennials

Perrenials that grow by roots and rhizomes Break apart the clump of plant material Leave roots, stem and leaves attached in each clump

Layering

Stem in contact with soil Tip layering -Flexible stem Bend stem tip to ground and cover with dirt Air Layering - Score or girdle a section of woody stem Cover with damp peat moss Cover with plastic Leads to rooting

Micropropagation

Tissue culture Grow plants from single cells Advantages: Vegetative/clonal Endangered species - Single leaf - Various plants Desirable mutation Pest free Small space

Plant Breeding

Traditional technique; ancient Ancestral and wild stock Controlled breeding -Pollen transfer Selection for desirable traits - Darwin's "artificial selection" "Green Revolution" 1970's High-yield wheat and rice Norman Borlaug Hybridization Crossing varieties with desirable traits Hybrid vigor: grows more robustly Often only in first generation, keep producing hybrids Beefsteak tomatoes Repeated crosses lead to new variety Polyploidy - Doubling of chromosome number Natural or induced -Treatment with colchicine -Disrupts mitosis -Resulting tetraploid bigger, more vigorous Hybridization then polyploidy Wheat Mutations -Natural -Induced ( Radiation Chemicals ) New traits Select for desirable trait Higher yield in Penecillium Radiation induced mutants in African Violet Tissue culture Callus tissue from plant cells Artificial medium Callus differentiates into shoots and roots Sterile conditions - Disease-free plants Many plants cloned from one plant Agriculture Plant conservation Horticulture Venus' Flytrap Artificial seeds Induce embryos and package with stored food and coating Protoplast fusion Separate cells Remove wall Protoplasts fuse, combining nuclei Nuclear transfer Allows only nucleus to be transferred and desirable organelles form one protoplast remain alone

Partial list of plants that have been transformed

* Corn, Potato, Rice, Sweet Potato, and Wheat are some of the top crop foods worldwide. Cassava has also been transformed.

True Fungi

-Chytridiomycota, Glomeromycota, Zygomycota, Ascomycota, Basidiomycota

Then, on to tissue culture & breeding!

-Take the successfully transformed cells and re-grow them into whole plants using tissue culture (the power of parenchyma!). • •Breeding: the new transgenic plants are bred with each other and existing crop plants that are vigorous (hardy and high quality) •Multiple rounds of breeding ensure that plants stably & consistently express the genes of interest

Characteristics of fungi

-eukaryotic organisms filamentous (unicellular) structure -simple organization -little differentiation in cells (unlike plants and animals) produce sexual and asexual spores heterotrophic - saprobes (feed on dead material) -symbionts (grow on or with other organisms) cell wall contains chitin (cellulose with amino cross links and nitrogen) - found in arthropod exoskeleton (indicates fungi are more closely related to animals than they are to plant even though they have cell wall like plants) Storage form is glycogen-similar to animals (vs plants which store starch) - in muscle and liver animals store glycogen

The number of copies of DNA in the sporophyte generation of plants is

2

Adoption of Herbicide Tolerant and Insect Resistant Crops Has Significantly Increased Since Their Introduction in 1996

2010 Totals: 93% of all cotton, 93% of soy, 86% of corn

Which of the following are characteristics of algal blooms? (Choose all that apply.) Select one or more: a. Are generally considered safe to swim in. b. Caused by increases in growth-limiting nutrients such as N and P. c. A dramatic rise in the numbers of organisms per unit area d. Water that is more beneficial to drink because of increased nutrient content due to an abundance of organisms e. Increase in oxygen available to other organisms in the water such as fish and aquatic plants.

A dramatic rise in the numbers of organisms per unit area, Caused by increases in growth-limiting nutrients such as N and P.

Which of the following would be considered transgenic? (Choose all that apply.) Select one or more: a. A petunia plant that is expressing one of its own genes for enhanced flower pigment with a piece of a virus gene to enhance its expression. b. A cotton plant expressing an extra copy of a gene that is also from cotton. c. Golden rice d. An apple variety produced through breeding of two genetically different parent lines of apple. e. A strawberry variety that expresses cold-tolerance genes from salmon.

A strawberry variety that expresses cold-tolerance genes from salmon., Golden rice, A petunia plant that is expressing one of its own genes for enhanced flower pigment with a piece of a virus gene to enhance its expression.

Agrobacterium tumefaciens is a soil bacterium that naturally causes (A) ________________ to form on plants by inserting pieces of its own DNA into plant cells and inducing cell division. The ability of Agrobacterium to insert DNA into cells was recognized, and the organism was developed into a vector to transform plants with novel genes. However, Agrobacterium was not initially successful at transforming what group of plants? (B) _____________________ Thus, another transformation method was developed, called (C) ______________________. This technology uses compressed gas to physically force DNA into cells that has been coated onto gold or tungsten particles. D. Name one advantage of using the method in "C" compared to Agrobacterium.

A) tumor-like growths B) monocots C) Microprojectile Bombardment ("Gene Gun Technology") D) Gene gun technology works much faster than Agrobacterium

Tests for Edibility of Mushrooms

ALL OF THESE ARE INCORRECT!!!!! • Poisonous mushrooms tarnish a silver spoon during cooking. • Edible mushrooms'cap will peel. • If animals eat the mushroom, it is not poisonous. • Poisonous mushrooms have a foul odor.

Natural Transformation Process

Agrobacterium tumefaciens (a soil bacterium) inserts a fragment of its own DNA into plant cells -induces those cells to produce the plant hormones auxin & cytokinin and divide -cells form a tumor-like growth called a crown gall Mary Dell Chilton and colleagues recognized the ability of the bacterium to do this, late 1970's.

Vegetative Progagation

Asexual Maintains favorable genetic combinations Mutation Desirable flower or fruit Disease resistance Dwarf form Variety of Methods Apply plant hormone - Auxin to stimulate rooting Many commercially available products Cover with plastic bag Reduce water loss Dipping plant part in rooting hormone powder. Specialized stems and roots Tubers Rhizomes Corms Bulbs Storage roots Often produced by plants as mechanisms of natural vegetative reproduction Tulips, daffodils May be divided with one node or bud Grafting -Insertion of a short portion of stem or a bud - Scion Onto a stem with roots - Stock Cambia must be in contact Must be related plants Attached in place

Tissue culture stages

Callus formation Shoot induction Change in media to induce root growth Maturation & transplantation

Determine whether each of the following is a characteristic of Agrobacterium tumefaciens-mediated transformation or of microprojectile bombardment

DNA is coated onto inert metal particles → Microprojectile bombardment Faster → Microprojectile bombardment Developed to transform monocots, but can also transform dicots → Microprojectile bombardment More precise with respect to the incorporation of DNA into cells → Agrobacterium Developed first → Agrobacterium Cheaper, overall → Agrobacterium

Traditional plant breeding results in the combination of multiple genes in offspring, some of which may not be desirable.

Deriving plants using molecular tools has been carried out since ~1983

Which of the following likely occurred as photosynthetic organisms made the transition from aquatic environments to land? (Choose all that apply.) Select one or more: a. A transition from multicellular body types to simpler unicellular forms. b. A cuticle developed to retain water in a drier aerial environment c. Organisms developed distinct organs with specific functions for transport and photosynthesis d. Proliferation of exposed gamete-producing structures to spread gametes more easily e. Development of relationships with fungi to help obtain phosphorous

Development of relationships with fungi to help obtain phosphorous, Organisms developed distinct organs with specific functions for transport and photosynthesis, A cuticle developed to retain water in a drier aerial environment

What is the correct oder of moss life cycle?

Gametophyte to zygote to sporophyte to spores

GFP Green Fluorescent Protein

Gene(s) from jellyfish taken and inserted directly

Fungi that form arbuscular mycorrhizae are classified in the

Glomeromycota

Moss gametophyte structure/composition

Have water storage and photosynthetic cells that compose their "leaves" Absorb water on their leaf surfaces through pores Their gametophytes are often packed together for structural support.

Basidiomycetes: Cell division

How does this perpetuate with 2 nuclei? • Secondary hypha is binucleate-mitosis occurs through clamp connections - one nucleus develops thumblike structure, other divides back into length of cell • Insure both nuclei in both cells - thumblike cell grows backwards, fuses with original cell, walls occurs between old and new cell, nucleus from each in each of the 2 cells - now have mechanism for maintaining nucleus from both primary hyphae and each of the cells • Clamp connections is not found in any other group

The two most widely adopted transgenic technologies in U.S. agriculture are: Select one or more: a. Increased nutritional value (e.g. Golden Rice) b. Virus resistance c. Insect resistance d. Herbicide tolerance e. Drought tolerance Feedback

Insect resistance, Herbicide tolerance

Basidiomycete Diversity

Lycoperdon puffball Phallus Stinkhorn Nidularia Bird's nest fungi Geaster Earth Stars Calocera viscosa

Asexual Spores

Penecillium asexual spores -conidium; conidiospores Aspergillus asexual spores (bulbus structure) -produced at the base and dispersed at maturity - breathing in spores causes aspergillosis (common in people who are immune compromised); we breathe these spores regularly but body can usually destroy these

Oomycetes

Phytophthora infestans - terrestrial form not aquatic form of oomycetes late blight of potato - cause of irish potato famine of 1846-1847 - 800K people died - 1million many immigrated out of ireland - still serious disease - reason why idaho is good for growing potatoes; this fungi doesn't grow well there Lumpar potato (widely grow in ireland during 1840's.)

Firefly luciferase

Plants engineered with the enzyme. When the substrate is applied, the tissues with the enzyme will glow.

Amanita muscaria Fly Agaric - the "generic" mushroom

Smurf House Super Mario

Match the following characteristics or examples of algae with the appropriate algal group

Some used for sushi wrapping (Nori) → Red algae (Rhodophyta) Some species may assist with nitrogen fixation → Cyanobacteria Toxins produced by these organisms, including the organism Pfiesteria, have resulted in massive fish kills on the NC coast and can have significant health impacts → Dinoflagellates (Dinophyta) Produce algin, which is used as a chemical thickener in multiple commercial products → Brown algae (Chromophyta) Have phycobilin, a pigment enables them to live in deep water with limited light availability for photosynthesis → Red algae (Rhodophyta) Bases of many aquatic food chains → Cyanobacteria Prokaryotic → Cyanobacteria Blooms can contributed to diminished water quality; toxins can be fatal if ingested in sufficient quantities → Cyanobacteria Used in road and road sign paint → Diatoms (Chromophyta) Have cellulose-based "armor plating" under their plasma membranes; flagella → Dinoflagellates (Dinophyta) Have members that are the largest of all algae, measuring up to 900ft long → Brown algae (Chromophyta) Have a nodal organization, very similar to land plants → Charophyta Carageenan, a thickener and emulsifier for dairy and other food products, is isolated from members of this group → Red algae (Rhodophyta) Cell walls composed of silicon and are grooved, making them very light-reflective → Diatoms (Chromophyta) Many are referred to as kelps → Brown algae (Chromophyta) Have chlorophylls a and b, similar to land plants → Green algae (Chlorophyta) Desmids (elaborate unicellular freshwater species), are members of this group → Green algae (Chlorophyta) Examples include Spirogyra, Chlamydomonas, and Ulva (sea lettuce) → Green algae (Chlorophyta)

A large percentage of the acreage of what four crops is now planted with genetically engineered plants?

Soybean, Canola, Corn, Cotton

Which of the following are true regarding Agrobacterium and how it was modified to serve as a transformation tool? (Choose all that apply.) Select one or more: a. Agrobacterium naturally infects a wide range of plants, including monocots and dicots b. Virulence genes responsible for causing plant cell infections were maintained c. Parts of the bacteria's chromosomal DNA were manipulated d. Agrobacterium, in its wild type (natural) state, causes crown gall tumors to form on plants e. T-DNA from the Ti plasmid was removed

T-DNA from the Ti plasmid was removed, Virulence genes responsible for causing plant cell infections were maintained, Agrobacterium, in its wild type (natural) state, causes crown gall tumors to form on plants

Name two of the types of layering techniques used to vegetatively propagate plants.

The main types are air layering, tip layering, simple layering, trench layering, serpentine layering and mound/stool layering.

Which of the following is the best definition for plant transformation? Select one: a. The insertion of T-DNA (transformation DNA) into cells via Agrobacterium tumefaciens b. The physical delivery and incorporation of DNA into a cell c. Introducing genes from one species into another d. A directed change in the physical appearance of cells as a result of changes in gene expression

The physical delivery and incorporation of DNA into a cell

Why is a plant hormone powder applied to cuttings in vegetative propagation? What is the plant hormone that is applied?

The plant hormone powder stimulates the formation of adventitious root and contains the plant hormone auxin.

In plants, spores are produced in:

sporangia

in all plants, meiosis results in the production of

spores

You're walking in the woods and see a fern plant. Immediately you recognize that the fern plant is the __ phase of the fern life cycle

sporophyte

name any structural adaptation that photosynthetic organisms developed as they transitioned from aquatic habitats to land?

adaptation of stomata, cuticle, rooting structures, *protection around reproductive structures.

nutrition

all do extracellular digestion - secrete digestive enzymes into matrix - absorb digestion products - resulting in decay Types: - parasites =pathogens (disease causing organisms) b/c attacks healthy tissue -mutualist: live in mutualistic symbiotic relationship with other organism; very common in plants - saprobes: feed on dead organisms and waste; important for being "natures clean-up group" - leaves broken down in autumn is due to fungi ex: mushrooms breaking down old stem and recycling its nutrients

Which of the following are usually necessary after plant tissues have been transformed? Select one: a. All of the above b. Verify transformation using one of any number of screening methods c. Grow up plants using tissue culture d. Breed the transgenic plant lines together to get a plant line that stably expresses the transformed genes of interest Feedback

all of the above

The largest of the algae; some are kelps

brown algae

structurally the most similar to land plants with their nodal arrangement

charophytes

Name one of the four crop plants in the U.S. for which the large percentage of acres planted is transgenic.

corn

prokaryotes that can produce potent toxins causing animal sickness and deaths

cyanobacteria

have flagella and armor plating composed of cellulose under their plasma membranes. Pfiesteria is an example

dinoflagellates

what do archegonia produce in the fern life cycle

egg (antheridia produce swimming sperm cells)

The salem witch trials in Massachusetts in the 1620 may have been a result of

ergot of rye poisoning

Match the way in which sporangia are borne with the group of seedless vascular plants

ferns: on the lower surface of the leaf equisetophytes: hanging under umbrella like structures lycopods: on the upper surface of the leaves (have vascular parts but no seeds) whisk ferns: fused together on the sides of the axes

determine the dominant life cycle generation for each major plant group

ferns: sporophyte bryophytes: gametophyte angiosperms: sporophyte gymnosperms: sporophyte

Delayed ripening in fruits

flavor saver

the dominant generation of moss life cycle is the

gametophyte

have chlorophylls a and b, similar to land plants, and can be unicellular, filamentous, thalloid etc,

green algae

Growth conditions for most mosses?

grow in/on saline, low pH, high calcium substrates, good colonizing organisms, require an environment with good water availability.

Farmers' Reasons for Adopting GE Crops

increase yields,save management time and make other practices easiers, decrease pesticide input cost, other

Colchicine is a chemical that can induce ___ in plant cells.

polyploidy

List 2 ways secondary hyphae are different from primary hyphae in the life cycle of basidiomycetes

primary hyphae develop from the germination of basidiospores. Primary hyphal cells are uninucleate primary hyphae don't form clamp connections, don't produce fruiting bodies while secondary hyphae can produce fruiting bodies. secondary hyphae form from the fusion of 2 compatible primary hyphal cells secondary hyphal cells are binucleate, form clamp connections,

why was Equisetum called scouring rush by pioneers?

would gather them, and silica was useful for scouring their pots and pans.

Live in low light conditions and have a pigment called phycobillin that helps them harvest any available light

red algae

cells walls are extremely reflective due to silicon composition and ornate grooving. used in road paints

red algae

produce carageenan, a thickener, and are used as Nori for sushi

red algae

Spores

single cells for reproduction and dispersal -asexual and sexual -sexual structures distinctive in each major group -easily carried on wind so travel great distances (even world wide, can be collected from planes)

features of mosses?

sporophyte generation of mosses is completely dependent on the gametophyte generation for support and nutrition mosses have distinct male and female gametophytes mosses absorb water on the surface of their leaves.

In a graft, the part of the graft that has the roots is called the

stock

Green fluorescent protein (GFP) is a good example of of a reporter gene.

true

Modern algal classification is such that there is a movement to split them among both Kingdoms Plantae and Protista, depending on body type.

true

With respect to their body type, cyanobacteria appear remarkably similar to some unpigmented bacteria. t/f?

true

cells of the sporophyte generation in plants have 2 copies of DNA per cell

true

despite the shared features of organisms within certain algal groups (red algae, green algae,) algal taxonomy and classification is complex and constantly changing. T/F?

true

Vegetative structure fungi

unicellular- in particular yeasy filaments= hyphae (singular= hypha) - coenocytic cells with multiple nuclei (no cross walls); keep growing -septate- have cross walls; grow new cells at the tip - have branches mycelia: cluster/mat of hyphae (singular: mycelium) - mat of hyphae - fruiting body (same as mycelia)

Oomycetes

water molds formerly considered fungi but now considered heterotrophic algae -reclassified due to new info from DNA work Coenocytic- cellulose cell walls which was unusual for fungi group range in metabolism from saprophytes to parasites ex: saprolegnia (italics) oosporangium (hypha releases sperm that fertilizes eggs, and eggs are released to form into new hypha) or Saprolegnia (italics) infection - attacks fish scales

Amanita phalloides Death Cap

• Cap 2-6 in. • Greenish cap • Stalk, gills whitish • Basal cup • Collar under cap • DEADLY POISONOUS - More deaths than other mushrooms - amatoxins - Squirrels are not affected by this mushroom

Eumycota = True Fungi

• Chytridiomycota • Glomeromycota • Zygomycota • Ascomycota • Basidiomycota

eumycota= true fungi

• Chytridiomycota • Glomeromycota • Zygomycota • Ascomycota • Basidiomycota

Diseases

• Dutch Elm disease - 1920's: shipment of wood carrying fungus that came in US, grows in zylem, clogs xylem which killed leaves, killed the trees • powdery mildews • ergot of rye - replaces rye flower - black, extends out from rye head, replaces the seeds - dyes bread red when baked (contains regotome which is LSD precursor ) - believed to have caused to symptoms Salem witch trials; was probably caused due to people tripping on LSD, not actual witchcraft

Treatment for Amanita poisoning

• Induce vomiting • Activated charcoal • No totally effective antidote, some promising

Look-alikes

• Morels • Morchella spp. - Edible and delicious • False Morels • Gyromitra esculenta - Potentially fatal - Induce vomiting

Mushrooms

• Mushroom hunting - Great hobby! - Know what you are doing! • Mushroom poisoning - Seek medical care immediately - Take a sample of the mushroom

Glomeromycota

• Mutualistic with plants • Form arbuscular mycorrhizal associations - Absorbs water and phosphorous for plant - Plant source of carbohydrates from photosynthesis (root, fungal spores, arbuscle inside a root cell) - grow tree like structure of branch hyphae - extend out of the soil that (fungi will absorb water and phosphorus to transfer to plant, plant returns carbohydrates to fungus)

Amatoxin

• RNA polymerase inhibitor - Stops protein synthesis • Mainly affects liver - First organ encountered - 7 mg fatal

Amanita Poisoning

• Reaction delayed • 3 stages - 6-24 hrs - Dry mouth, nausea, vomiting abdominal pain, diarrhea, shock - After 24 hrs • False recovery - Recurrence • Abdominal pain • Liver failure Amanita phalloides

Fly Agaric Amanita muscaria

• Red or orange cap with white flecks; white stalk with collar • Hallucinatory - Poisoning rare; intoxicant - Ibotenic acid • Widespread • Cap used to kill flies • Often used as "generic" mushroom (solar lights)

Edibility Tests

• There is NO (repeat - NO) general test for edibility of mushrooms. The only way to tell edibility is to know the mushroom!!!!! • Keep in mind that some edible mushrooms resemble some poisonous mushrooms. • Some mushrooms may cause gastric distress to some people and not others. • Collect wild mushrooms only with a trained collector; then become a trained collector.

Chytridiomycota

• Unicellular to coenocytic • Saprobes to parasites • Flagellate spores (interesting characteristic) •Important: - Saprobes in aquatic environments - act as decay elements - Amphibian diseases Chytridiomycosis - Batrachochytrium spp. • Decline of frogs and other amphibians

Ascomycota

• ascocarp - contains asci (sing. = ascus) • Contain asexual spores = ascospores - sexual cycle : formation of asci in ascocarp (many forms - cup - truffles - Morchella = morels (covering lined with asci) - will usually be 8 - because meiosis produces 4 cells, and then 4 cells with undergo mitosis to produce 8 cells.

Zygomycota

• asexual - sporangiospores • sexual - form zygosporangium - and +/- hyphae fuse, wall off (coenocytic) - swell in size - +/- nuclear fusion and meiosis occurs (produces sexual spores) - zygosporangium forms next • thick-walled • ornamented • produces sexual sporangiophore (looks identical to asexual sporangium but produces sexual spores instead.)

Zygomycota zygomycetes

• coenocytic hyphae • mutualists, saprobes, some parasites Rhizopus stolonifer (most common-black dots are the asexual sporangia) - black bread mold - Pilobilus - phototropic - grows on dung - lens points toward sun, triggers liquid to reach boiling point, expels sporagnium with string on it, wrapped grass with sporangia are eaten by horse, fungi deposited into dung of horse

Products

• edible mushrooms - Agaricus bisporus • grown in dark on sterilized horse manure - Portabella, Shiitake, others - Grow-your-own-kits

Ascomycota ascomycetes, cup fungi

• hyphae septate • uni-or binucleate, some unicellular forms (ex: yeast) • spores germinate to form hyphae with single nucleus • produce asexual spores in abundance - Aspergillus, Penecillium (from drug penecillin) • budding - yeasts - asexual means of reproduction

Basidiocarp

• mushroom (most common of these) - cap on a stalk - gills or pores under cap • site of basidia - as mushroom grows, terminal cell expands = basidium • nuclei fuse (only time they fuse), undergo meiosis • four points on basidium (looks like udder on a cow) • sexual spores form at points -basidiospores pores act as openings for tubes volva may or may not be present or may or may not have scales development of mushroom comes from the "button" - the covering between cap and stem bursts open and becomes the "ring"

Basidiomycota or Club Fungi

• mushrooms, puffballs, bracket fungi, rusts, others • uni - or binucleate (unusual that most of lifecycle is spent in binucleate stage- very unusual for organisms) • cells septate - septum with ring around pore (unusual that there is a pore around it) • vegetative growth: - spores germinate to form short haploid primary hypha - primary hypha fuses with a comptaible hypha, forming binucleate cell to form secondary hypha - mycelium is composed of secondary hyphae so all cells have 2 nuclei

Lichens

• mutualistic relationship - Fungus: most are ascomycetes • gains photosynthate - Photobiont: alga or bacterium • gains protection, water, nutrients • reproduce asexually - fragments - packets of algal and fungal cells • slow growing • important in cycling nutrients • pioneer species - rock and soil colonization • sensitive to pollution - air-quality bioindicators - nitrogen oxides and sulfur dioxide

Dangers and Diseases

• poisonous mushrooms - Amanita virosa = death angel • white, with a collar • piece the size of a pea will kill • toxin blocks protein synthesis • hallucinogenic mushrooms - Amanita muscaria = fly agaric • red cap with white flecks • Siberian eskimoes - Psilocybe • plant diseases - wheat rust - corn smut

Products from ascomycetes:

• yeast products - bread, alcoholic beverages • cheeses (ex: Roquefort- smelly because of fungi growing) • Penecillin (penicillium is released to kill surrounding bacteria) • Morels (mushroom) lined with asci, edible

Insect Resistance

•Genes from the Cry gene family of the bacteria Bacillus thuringiensis (Bt), which encode for insecticidal toxin • •Insects ingest protein and eventually starve •Implementing BT crops during 1996-2005, reduced insecticide use on cotton and corn by 35.6 million kg of active ingredient European corn borer has caused significant damage to corn crops in the U.S.

Applications of Transgenic Plants

•Insect resistance -Bacillus thuringiensis toxin production •Herbicide tolerance •Pathogen resistance (viral, fungal, etc.) •Improved nutritional content •Increased biomass •Drought, cold, and salt tolerance •Phytoremediation •Production of novel compounds •Regulate metabolic pathways and plant gene expression and physiology

When Pathogens Attack: Engineering Virus Resistance

•Papaya plants are impacted by a virus called Papaya Ring Spot Virus (PRSV), shown at left •Papayas have been engineered to be resistant • •Potatoes have also been engineered against Potato Virus X Rainbow line of papayas grown in Hawaii

Producing Genetically Engineered Plants

•Process using Agrobacterium was effective in dicots, but not effective for monocots when first developed -Led to the development of an alternative method •Biolisitcs or microprojectile bombardment: uses a particle gun or "gene gun" • DNA of interest is coated on non-reactive metal particles (Gold or Tungsten) and physically forced inside of plant cells using gas pressure

What are Genetically Engineered Plants?

•Sometimes referred to as "genetically modified" • •Transgenic Plants: plants in which DNA from another species has been integrated into the genome • •Transgenic plants are created through transformation- the genetic manipulation of a cell resulting from delivery and incorporation of DNA from another source -Transformation is often referred to as an "event"

Biofuels (Cellulosic sources)

•Switchgrass produces five times more energy than it required to be grown, harvested and processed into ethanol •Hybrid poplar trees have been bred as fast-growing biofuel sources •Miscanthus (right) grows rapidly, has low nutrient requirement, and produces a large yield per acre -It's also a C4 plant, so it can withstand high light and some heat stress sugar fermented by yeast to produce ethanol

Concerns about transgenic crops

•Unknown long term effects on human and animal health •Development of insect resistance to Bt toxin • •Unintended effects on non-target organisms •Modified plants grown within the field will outcross with wild types • •Foods are unsafe, toxic, or allergy-causing ex. Nut allergies if specific genes from nuts are cloned into other plants •Concern that crops have reduced yield •Natural varieties work better (landraces) •The industry of genetically modified foods is profit-driven, not need-driven •Inequitable distribution of resources •Farmers required to buy seeds from companies each year

Genetic Engineering Using Agrobacterium

•Use recombinant DNA technology to remove most of the genes that induce tumor formation (called T-DNA), but maintain genes (called virulence genes) that are responsible for inserting DNA into plant chromosomes. • •Insert DNA that encodes for desirable traits: genes of interest -For example: resistance to insects • •Result is a bacterium that will insert the DNA that you want but no crown gall formation • •Start with fragment of DNA from source organism(s) • •Insert fragment into Agrobacterium plasmid • •Grow up the bacteria and "infect" plant cells • •End-result is a plant cell that will potentially express the gene(s) of interest

Gene Gun" Technology

•Used to transform several crop plants - useful in monocots (and dicots) • •Most challenging aspects of transgenic plant production is transformation and gene expression • •Allowed advancements toward the development of blue carnations even though cut flowers do not produce blue hues • •Much faster, but more expensive and not as precise!

After Transformation, Then What?

•Verify that transformation was successful.....but how? -Amplify the transgene DNA using PCR -Select for the trait you are engineering •If you are engineering for resistance against an herbicide, then apply the herbicide! -Physical indicators -Reporter genes

Another Trait: Added Nutritional Value Example: Golden Rice

•Vitamin A deficiency is a severe problem in developing nations, leading to poor growth, bone under-formation, and blindness • •Beta-carotene (a carotenoid) is a vitamin A precursor, and is chemically converted in the small intestine • •Rice engineered with two enzymes in beta-carotene production pathway from daffodil

Herbicide Tolerance

•Weeds are a significant problem in crop fields • •Tilling is expensive and time-consuming •Engineer crop plants with an enzyme that will make them resistant to herbicides -Crops live -Weeds DIE