Unit 3 /10-31-22 Flashcards
CMS
Cytoplasmic male sterility
If you collected the seeds from your hybrid they would
not be great, hybrid benefits only come from first gen seeds from non hybrid parents
Benefits from hybrids
High yields
vigor and uniformity
Expensive
Cannot save seeds
Open pollinated
Self pollinate or cross-pollinate with other plants
How to store seeds
Keep in cool, dry place
Paper packets are best kept in
tightly closed jars or containers
and maintained around 40°F with
low humidity.
What is required for seeds to germinate?
Water, temp, oxygen
light is not required for all seeds
Those interested in saving seeds should
stick with open-pollinated varieties,
because seed saved from hybrids does not
“breed true”; the next generation won’t
look exactly like the original variety.
Water
- Water is the critical first step
- Without water, seeds will remain dormant
- Too much water causes seeds to rot
- Too little water causes the embryos to die
- Try not to displace seeds by excessive flooding. Germination
Oxygen
- All viable seeds need oxygen.
- Seed respiration rate increases
dramatically during germination. - Growing medium must be loose
and well-aerated. - Too much water can inhibit
germination!
Light
- Some seeds require light to germinate.
- Dill, - Some seeds require darkness to germinate.
- Kale and cauliflower - Some light is not a factor in germination.
How to plant seeds that require light?
- When sowing light-requiring seeds, do not bury them.
- Cover them lightly with fine peat moss or fine vermiculite.
- Provide supplemental light for 6-12” above the seeds for 18 h per day.
Temperature
- Each plant has a specific optimum and range within which germination will occur.
- Cool-season Crop
- Peas = Hypogeal - Warm-season crops
barley, oats, canola = 40-68
Cool-season vegetables
- Asparagus, beets, broccoli,
Brussels sprouts, chives, cabbage,
carrots, cauliflower, Swiss chard,
kale, leek, lettuce, onion,
parsnips, peas, radishes, spinach,
and turnips.
Less susceptible to frost damage
Warm-season vegetables
- Beans, corn, cucumbers,
eggplant, melons, peppers,
zucchini and summer squash,
pumpkin and winter squash,
sweet potato, tomato,
watermelon.
Establishing Seedlings
- After germination, seedlings must receive bright light.
- Insufficient light causes seedlings to “stretch”
Seedlings
- Ideally, seedlings should be dark green and sturdy.
- Symptoms of nutrient deficiencies include pale yellow
foliage, purpling of leaves (older plants).
Very sensitive to water
Transplanting and Handling
- If plants have not been seeded in
individual containers, they must
be transplanted. - What happens if you leave the
seedlings too long? - Ideal time is when the first true
leaves appear between the
cotyledons (called “seed” leaves).
Types of ways to mess up seedling
light, pot too long, water, fertilizer
Transplanting
- Carefully dig up the small plants with a knife or wooden pot ladle.
- Gently ease them apart in small groups to make separating individuals easier (do not tear roots).
- Handle small seedling by their leaves, not their delicate stem
- After transplants, seedlings need nutrients.
- Some commercial soil mixes have fertilizer already added.
- If you are using media without fertilizers, you will need to add supplemental nutrients.
- Young seedlings are easily damaged by too much fertilizer, especially if they are under moisture stress.
How do you know if you should add fertilizer to your plant
Containers
- Garden containers come in many different types and materials.
- Examples wooden or plastic flats, trays, cell-packs, and pots for starting seeds.
- Drainage at the bottom of the container is critical for plants.
- Drainage allows water in the soil to drain freely so adequate air is available for the roots.
- Few plants can survive in stagnant water!
examples that can grow in low oxygen tensions
rice
What is the most prominent gas in out atmosphere
approx. 80%
All plants use _________ in the form of ammonia?
Nitrogen
What is Biological Nitrogen Fixation
The process that changes N2 into biologically useful NH3
This process is mediated in nature only by N-fixing rhizobia bacteria
How to know a legume plant is fixing nitrogen
the nodes are pink or red
The nitrogen fixation (N2 fixation) process between
legume plants and rhizobia
bacteria is referred to as a _________________
symbiotic relationship
Each organism receives
something from the other and
gives back something in return
What is the trade off for the legume plants and bacteria?
- Bacteria – provides nitrogen
- Plant – provides
- carbohydrates
- Protection
What influences nitrogen fixation
- Directly related to plant
growth rate (drought,
temperature, plant
nutrients, disease, etc.)
*sufficient leaf area to
intercept sunlight is
essential
What is the quantity of nitrogen fixed by legumes
The quantity of nitrogen fixed by legumes can range from almost none to over 200 lb/acre
How can we use legume plants to reduce our use of synthetic fertilizers?
What are some factors that influence the quantity of nitrogen
fixed?
*Nitrogen in soil
* Rhizobia strain
* Amount of legume plant growth
*How the legume is managed
* Length of growing season
Will legume plants take nitrogen from air or soil first?
If given the choice, legume plant will remove nitrogen from the
soil before obtaining nitrogen from the air
it elucidates soil fertility
White clover, alfalfa, vetch, annual medics, cowpea, etc. all require different strains of Rhizobium bacteria
* Why?
What are the limitations of Rhizobia bacteria
expensive
It can be difficult to introduce a
new legume species into a
pasture that had different
legume species growing for
several years
Which do you think would take more nitrogen from soil (legume or
grass)
Generally, fibrous root
system is more efficient at
extracting nutrients and
moisture as compared with
a taproot
Therefore in a legume/grass
mixture, the grass will utilize
more of the soil nitrogen
The primary pathway for nitrogen
transfer from legume plants to soil
are through _________ and
______________
grazing livestock
lant decomposition
Where Other
consideration
s with
pasture
grazing and
nitrogen?
- Distribution of feces and urine on the pasture
- Much of the animal feces stay near shaded trees and
water source
the more you can depose th material, the
how to plants decompose
Symbiotic relationship between
fungi and plant roots
Mycorrhizal
Fungi
* Mycorrhiza means “fungus root
enhance nutrience and eeater =
what is
PH lowers
Do you think rhizobium forms symbiotic relationships with many different species of plants.
NO!
They are host specific
Will legume plants take nitrogen from the air or the soil first?
Soil - it is easier
Are monocots more efficient in extracting nitrogen from the soil?
yes, true!
root system is dense and spreads around covering more area.
What % of nitrogen passes through an animal
80-90%
50% of nitrogen in
urine is lost through volatilization
what are 4 ways mycorrhiza benefit plants?
help with intake of nutrience
Is there an evolutionalry advantage to this symbiotic relationship
PH, Water, Nutrient uptatke
Are Lichens plants
NO
What are lichens?
- Symbiotic association involving a fungus and green algae
- The fungus obtains carbohydrates produced by
photosynthesis from the algae - Green algae receives protection from desiccation and UV
light - Wide range of lichens found on every continent
- Rocks, sidewalks, graves stones, cars, etc.
Do lichens kill trees?
NO
Why are there more lichens on a dead tree
More are visible on dead tree, just hanging out on the bark
Do lichens produce oxygen
Yes they use photosynthisis
What is plant pathology
Plant pathology is a science that studies plant pathogens and diseases.
wanting to Improve the chance of survival of plants or limit yield loss
Economic importance of plant pathology
world wide 20% lost in yield due to pathogens
about 42% yield lost combined
Disease definition
Any physiological or morphological change in a living
organism due to a continuous irritant (abiotic and biotic)
Parasite
An organism living on or in another organism from which it
obtains food
are all parasites are pathogens?
YES
Of all of the disease in plants ________ are caused by fungi
80%
Biotic
living organisms that cause disease
Abiotic
noninfectious factors that may affect many plants in an area
Humans iron deficiency is an ______disease
abiotic disease
Athletes’ foot is an example of a _____ disease
Biotic disease
What are 3 things you need for disease
Host
Pathogen
Environment
What are 3 things you need for disease (amp)
Susceptible host
Virulent pathogen
Favorable (conductive) environment
Who is Robigalia
The Robigalia was a festival in ancient Roman religion held April 25, named for the god Robigus. Its main ritual was a dog sacrifice to protect grain fields from disease
What is monoculture
Lack of genetic variation
What is The Great Bengal Famine
- Rice is one of Asia’s main food
staples and in 1942 it had almost
disappeared. - The area of Bengal in West India had
experienced a disease that reduced
rice yield to 40-90% - 3 million people died from
starvation - Brown Spot (Cochliobolus
miyabeanus)
Southern corn leaf blight (bipolaris maydis)
- In 1970, almost 85% of US corn fields were planted with one type of corn (Tcms)
- Devastating epidemic
- The economic losses totaled
about 1 billion dollars in USA
Plant diseases as the wrath of gods – Theophrastus
- People continued to suffer from
hunger and malnutrition due
partially at least to diseases
destroying their crop. - Spontaneous generation
(production of living organisms
from nonliving matter)
What was the First management practice of a plant pathogen
- In the mid-1600s, a group of French farmers noted that wheat rust was always more severe on wheat near barberry bushes than away from them.
- The French government passed the first plant disease laws that forced towns to remove barberry trees.
What the issue in the Irish famine
The lumper potatoes were susceptible
phytopthora infestance
What started the scientific discipline of plant pathology
Potato blight
CMD
caused by virus
How do plant pathologist differ from medical pathologist
plat pathology is based on yield
Plant pathology options
IPM
Fungicides
genetic resistance
Why manage plant disease IPM?
What are some of the consciences if diseases are not manages (5)?
Which example would be a loss of a natural rescores
Dutch elm disease
What is the first step in determining a disease is for a plant
Identify the host plant
Fungi Indicators
Mycelia and/or spores
Bacteria indicators
Ooze
Nematode indicators
Cysts
poor would eat
Rye
Rich would eat
Wheat
Rye is susceptible to Ergot
Fusarium Head Blight (scab)
Disease on cereal crops (wheat, barley)
Mycotoxin - DON
What is the toxic in ergot
elcoloides
sclerotia
the pathogens names are always italicized, the ———- is not+
Livestock and SCAB
Consuming grain at the levels greater than 1 ppm health risk in humans
livestock - vomiting, feed refusal and aborted calves
Durum wheat for pasta
What foods are often staple foods
Carbohydrates
What is considered a crop
- A crop is a plant that can be grown
and harvested for food or profit
What are the 6 categories of crop
- Six categories of crops
1. Food crops
2. Feed crops
3. Fiber crops
4. Oil crops
5. Ornamental crops
6. Industrial crops
800 million people rely on cassava
Feed Crops
- Are harvest for livestock consumption
(example oats and alfalfa) and barley - Forage crops are important for livestock
farming. Animals feed directly on forages
crops such as grasses, alfalfa, etc. - FAO – 33% of arable land on Earth is used
to produce food for livestock
What are the world leading staple foods?
- Cassava, maize, plantains, potatoes, rice, sorghum, soybeans, sweet potatoes, wheat, and yams
- Note – crops do not always feed people near where they are grown. Crops grown in one place might be exported to another.
What is FAO?
Food in agricultural
What is a food staple?
- Food that makes up the dominant part of a population’s diet
- Food staples are eaten regularly – even daily – and supply a major proportion of a person’s energy and nutritional needs
What influences popularity of a food crop?
- Climate
- Accessibility
- Trade
- Culture
What is GDD?
Growing degree days
How many days of this temperature are required for a plant to flower.
Fiber Crops
- Fiber crops are harvested for textile and paper products. Examples include cotton and hemp.
- Cotton is the most popular fiber crop in the world!
Oil Crops
- Oil crops are harvested for consumption or industrial uses. Examples include canola, corn, and sunflower.
- Fuel made from oil crops is called biofuel.
Ornamental Crops
- Are harvested for landscape gardening. Examples include azalea, tulip, etc.
- Ornamental crops can play an important role in economic
activity in developing countries. Kenya is a major exporter of
roses and carnations.
Industrial Crops
Tobacco and rubber
- Industrial crops are harvested for there products in factories or machines. Examples include rubber and tobacco.
- Rubber is produced naturally from a wide variety of plants but predominantly from the Hevea tree.
Which crop plants are the most important in terms of
production (worldwide)?
Corn!
Which crop plants are important in terms of calories
and protein?
protein - Soybeans Potato
calories - sugarcane and potato
Which crop plants are important in terms of calories
and protein?
- In 2020, the top 10 agriculture-producing States in terms of cash receipts were (in descending order): California, Iowa, Nebraska, Texas, Kansas, Minnesota, Illinois, Wisconsin, Indiana, and North Carolina.
What are the leading farm commodities, in terms of
cash receipts, in the United States?
- In 2020, the 10 largest sources of cash receipts from the sale of U.S.-produced farm commodities were (in descending order): cattle/calves, corn, soybeans, dairy products/milk,
miscellaneous crops, broilers, hogs, wheat, chicken eggs, and hay.
What is a weed?
- Any plant that interferes or has a negative impact on the activities of people
- “unwanted”
Is corn open pollinated or a hybrid?
Hybrid
can a diseased plant be a weed
YES
What 4 things do weeds take away from crops
Nutrience
Space
Light
Water
Why is weed control important
- Livestock producer
- Home
- Medical
- Recreational
- Aesthetic
- Hort/turf/agronomic
- Preserving native species
Where to go to check what plants are toxic to livestock
Wisconsin Extension
WSSA
Livestock Producer concerns
- Nuisance
- Poisonous
Homeowner
landscaping
pets
children
Medical
Jimsonweed
- Near Jamestown many of the governor’s
ill-equipped, famished soldiers devoured
the thorny fruits of a plant growing in
profusion thereabouts and promptly
died. Shortly thereafter, Bacon himself,
aged 29, died suddenly “of a mysterious
fever called the ‘Bloodie Flux.’” - Thereafter, the plant was known as
“Jamestown weed” — a designation that
in time became “jimson weed.” By any
name, it has a long and lethal history.
Aquatic settings
Lawn
Crop loss
What are the 3 weed distributions
Regular
Random
Patchy
Would you see more annuals or perennials in a patchy weed setting
Perennials
rysomes and stolons
Would you see more annuals or perennials in a Random weed setting
Annuals
