Introduction to Field Crops

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What is Vernalization

The need for cold for a period of time before germination

What is Field Capacity

How much water the soil can hold without getting anaerobic conditions

What is a crop

Parts harvested for human uses

Involves cultivation in the field and domestication

What do we look for in domestication

Trait of interest

Lack of shattering

Lack of seed dormancy

What is a Field Crop

Not ornamental

Not a fruit or vegetable, forages and hay

What are the steps of Crop Production

1. Destroy plants already on site

2. Stir soil (sometimes)- destroy seedbed

3. Plant

4. Destroy weeds

5. Protect against pests

6. Gather product and sell

What is Agronomy

The science and practice of crop production to produce feed, fibre, and fuel

What do agronomists need to understand

Plants, soils, insects, microorganisms, climate and how they interacts with each other within agroecosystems

They work everyday to improve crop production practices, breed improved crop varieties, develop improved pest management practices, and minimize the impact of agriculture on the environment

What are Biotic factors/Stress

From living organisms

Examples: weed competition, soil microbes, insects, and diseases

What are Abiotic factors/Stress

From non-living factors

Example: light, temperature, rainfall, soil characteristics

What is a Agronomist

General term for someone who works in agronomy

What is a Agrologist

Certification by the Saskatchewan Institute of Agrology

What are the Current Challenges in Agriculture

Global warming

Cost of inputs

Herbicide resistance

Population growth

Public mistrust

What is Sustainable Development

Economic development that meets the need of the present without compromising the ability of future generations to meet their own needs

What is Sustainable Agricultural Development

The management and conservation of the natural resource base, and the orientation of technological change in such a manner as to ensure the attainment of continued satisfaction of human needs for present and future generations

What are the 3 dimensions of sustainability

Environmental

Social

Economic

The conservation of the environment is necessary but not sufficient for real agricultural sustainability

What are some challenges identified by Hamel and Saindon

Food and water security

Air quality

Climate change and the environment

Rising population

Public trust and transparency

What are the 3 perspectives of Sustainable Agriculture

Production efficiency- supply of food with increased efficiencies to feed increasing global population while minimizing negative environmental impacts

Demand restraint- unsustainable consumption patterns and food waste

Food system transformation- inequities amongst actors in the food system (rich and poor)

What are the sustainable development goals

No poverty

Zero hunger

Good health and well-being

Quality education

Gender equality

Clean water and sanitation

Affordable and clean energy

Decent work and economic growth

Industry, Innovation, and Infrastructure

Reduced Inequalities

Sustainable cities and communities

Responsible consumption and production

Climate action

Life below water

Life on land

Peace, justice, and strong institutions

Partnerships for the goals

Which UN development goals could agricultural professionals contribute to

Zero hunger- produce enough food for growing population

Climate action- greenhouse emissions

Clean water and sanitation- prevent runoff

Decent work and economic growth- provide jobs

What is global circulation

The climate system as a whole

Consists of 3 large cells: Hadley, ferrel, and polar

What are the cells in global circulation

Largest are Hadley, then ferrel and smallest are polar

The ferrel cells are not effected by heat and the cells rotate like gears

They explain how major environmental zones (wet or dry) tend to occur in the same latitudes globally

What is the movement caused by the cells cause by

Hot air rising at the equator and at the boundary of the polar cell which forces the Ferrel cell to rotate in the opposite direction

Coriolis effect creates a lateral movement from the rotation of the earth

How do winds effect the ferrel cells in the prairies

Prevalent winds in the ferrel cell cause eastward winds in the prairies

Blow east to west

How is precipitation effected by the rockies

The mountains interrupt that air so there is less moisture as you move inward

Warm moist air and lots of moisture as you come up the mountain

Dry air and less moisture coming down the mountain because of the evaporation which is caused by the compression and warming as it comes down

Called the rain shadow effect

What are chinook winds

Winds coming down the mountains

How would you describe the environment in the Canadian Prairies

Semi-arid

Long cold winters and short hot summers

Grass land environment

What is rainfall anomaly index

Precipitation only

What is palmer drought index

Drought and heat- worse then just drought

Precipitation, temperature, and evapotranspiration, soil water capacity, weighted towards moisture state of previous month

What are deciles

Statistical distribution of precipitation totals

What is aridity

Long term climate phenomenon

What is drought

Temporary phenomenon

Impact of climate change

Increase in temperature at winter or at night

What are some of the abiotic factors that limit production in the Canadian Prairies

Short growing season- 100-135 days frost free

High winds

Limited moisture- due to the rockies called the rain shadow effect

What are the 2 factors that limit the characterization of climate zones

Temperature and precipitation

What does too much and too little light do to a plant

Too much light causes oxidative stress and bleaching of leaves

Too little light causes shorter growth

What kind of light do plants absorb

Absorb blue and red spectrum

Reflect green light

What is photoperiodism

A biological response to a change in the proportions of light and dark in a 24 hour daily cycle

What are the 3 types of plants

Short day- light period shorter then critical period

Long day- light period longer then critical period

Day neutral- will flower regardless of day length

What it C4 Photosynthesis

PEP carboxylase activity is not inhibited by O2

Kranz anatomy

More efficient they use 5 ATP but C3 uses 3 ATP

Better adapted to high heat and dryness because they have a smaller stomata which means less water loss

What is C3 Photosynthesis

CO2 is added to a phosphorylated 5-C sugar to form ribulose bisphosphate (RuBP)

Reaction is catalyzed by the enzyme ribulose bisphosphate carboxylase oxgenase (RUBISCO)

Forms a 6C compound that breaks into 2 molecules of 3-phosphoglyceric acid (PGA)

What is Photorespiration

This process uses O2 and releases CO2

Increases with light intensity and temperature above 25°C

Decreases with increasing atmospheric CO2 concentrations

C3 Vs C4 Photosynthesis

Leaf anatomy- in C3 there are no distinct bundle sheath of photosynthetic cells and in C4 they have kranz anatomy which is a well organized sheath rich in chloroplasts

Carboxylating enzyme- in C3 is rubisco and in C4 is PEP carboxylase followed by rubisco

Transpiration ratio- in C3 is 450-950 and in C4 is 250-350

C3 has photorespiration (25% loss of fixed C) but C4 does not

Optimum temperature for photosynthesis- C3 is 15-25°C and in C4 is 30°C

Minimum ppm CO2 required for photosynthesis- C3 is 30-70 and C4 is 0-10

Examples- C3 is soybean, alfalfa, wheat and in C4 is corn, millet, sorghum, sugarcane, amaranth

What is CAM photosynthesis

Plants employ both Calvin and C4 pathway

Temporal separation of both pathways occur in the same cell

Need a large vacuole where magic acid is stored and abundant chloroplasts where CO2 can be used to make CH2O

At night CO2 is fixed by PEP carboxylase and oxaloacetate is reduced to manic acid and stored in the vacuoles

During the magic acid is decarboxylated and CO2 is transferred to RuPB in Calvin cycle

When does enzyme activity occur

Between 5°C and 25-30°C

Linear relationship between temperature and growth

Below 5 and above 30 this relationship breaks down

How do you calculate heat accumulation

Cumulative growing degree days= cumulative sum over time period

CHU= Sum of GDD= Tmax+Tmin/2- Tbase

What is heat stress

Can speed up development and cause early senescence

It reduces the energy the plant can invest in growth and reproductive structures which can lead to abnormal pollen development and ovary sterility which causes abortion of grains

How does water effect plants

Essential for life

Used in photosynthesis and a solvent for nutrients

Helps with structure

Plants are 65-90% water except for the seeds

What happens if there’s too much water and how can you fix it

Too much removes the oxygen out of the root systems and toxins may form in the soil if flooding is prolonged

Drainage or good plant structures so they can store more

What is field capacity

The water remaining in the soil after it has been throughly saturated and allowed to drain freely

What is permanent wilting point

The point where the moisture content at which plants wilt and fail to recover

What is available water capacity

The difference between field capacity and permanent wilting point

What factors affect the available water capacity

Soil texture- clay holds more water

Rock fragments- more rocks cause more damage

Organic matter content- more organic matter causes a higher holding capacity

Compaction- if all pour space is compacted there’s no water

Salinity

Restrictive layers- compaction at certain levels

What nutrients make a plant

Obtained by air through photosynthesis- carbon, hydrogen, and oxygen

Macronutrients- nitrogen, phosphorous, potassium, and sulphur

Secondary elements- calcium and magnesium

Micronutrients- iron, copper, manganese, zinc, boron, molybdenum, chlorine, cobalt, lead

Use fertilizers for most of these nutrients

What is wheat

One of the first domesticated crops in the Fertile Crescent

20% calories and protein in our diet

Can be grown in vast different climates and conditions

#1 for production and acreage in Canada and generally top 5 for exporting

What is the green revolution

When deaf genes were discovered in wheat to reduce lodging, and create a better harvest index

Used this knowledge in wheat breeding programs

What is acclimation

A process of physical and physiological changes to prepare the plant for winter

What is winter hardiness

A measure of the plant to survive the winter without injury

Spring wheat Vs Winter wheat

Spring wheat- planted in may, no vernalization needed, day length sensitive or day neutral

Winter wheat- planted in September, vernalization needed, day length sensitive, acclimation and winter hardiness

Benefits of Winter crops

Early spring time is prime growing season which leads to faster growth and canopy closure

The soil moisture is adequate, daytime temperatures can get near optimum, less weeds to compete against in early spring

Mature early and escape the heat and terminal drought in August

What is the Canadian Grain Commission

Established in 1922 to establish quality standards

It is a grain company licensing

All bulk grain to be exported by ship is inspected by the CGC

Involved in the allocation of railway cars for grain

Grading factors are based on visual assessments

What is Dockage

Any material intermixed with a parcel of grain other then kernels of grain of a standard quality fixed by or under this Act for a grade of that grain that must and can be separated from the parcel of grain before that grade can be assigned to the grain

What is falling number

Measure of the activity of the alpha amylase enzyme (splits starch into smaller carbohydrate compounds)

Points out to early stages of sprouting in the absence of visual symptoms

Important for baking quality

What products are made with wheat

Flour for breads, pasta, cookies, noodles, etc

What are the wheat market classes

Are 11 western wheat classes some have minimum protein levels

7 eastern wheat classes

Variety designation list which they need to meet protein levels and be on list for this specific class- if its not on the list its animal feed

What is bread wheat

A hexaploid (6N) from the interspecific hybridization of Tritium species (AA genome) with Aegilops species (BB and DD genome)

Durum and emmer wheats are a tetraploid (4N) intermediaries (AABB)

What is corn

Originated in central and South America

Most important crop worldwide in terms of production and most traded crop in the world market

C4 cereal

In Canada it is grown in Ontario and Quebec for grain and the rest of Canada for silage

Produced by the hybridization of genetically dissimilar parents which leads to a hybrid vigor

Corn types

Dent (yellow/white)

Flint

Sweet

Popcorn

Flour

Uses of corn

Popcorn, sweet corn which is eaten directly, tortillas, corn chips, livestock feed, ethanol, plastic, other industrial products

What is hybridization

Crossing of inbred lines of crop plants

Hybrids are offspring of genetically dissimilar parents which results in a hybrid vigor

Monoecious plants

Crossing field= 4:1 ratio of female to male

Degassed female

May need to stagger planting to synchronize male pollen release with silk emergence

What is barley

Domesticated in the Fertile Crescent

Ranked 5 for worldwide acreage

4 in Canadian production after wheat, canola, and corn

A C3 crop

2 row and 6 row barley cultivars

Grows mostly in dark brown or black soil zones

Uses of barley

Malting (beer and whiskey)

Feed/forage

Speciality hulls cultivars are used for food products- gluten free and beta-glucans

Breeding efforts of barley

Focused on malting for craft breweries

Expanded efforts on DNDF and leaf diseases

Reduced efforts on high amylose type

What is Oat

6th or 7th depends on the year in terms of most important based on production

C3 crop

Grows mostly in dark brown or black soil zones and can be found in the most Northern agricultural locations

Uses of oats

Food- breakfast cereals and baking

Animal feed

Dairy substitute- oat milk

Plant-based protein products

What are the types of cereal inflorescences

Spike- wheat, barley, rye, triticale

Tassel (male only)- corn

Spike-like panicle- canary seed

Panicle- oat, rice sorghum

What is Canary seed

C3 crop

Speciality crop used for bird seed mixtures

Some efforts to get crops classified safe for human consumption and introduced into various food products

A minor crop

Production mostly in Sask because Professor Pierre Hucl from the CDC developed it

What is Rye

C3 crop

Both fall and spring types

Varieties can be diploid (2N) or tetraploid (4N)

Uses of rye

Livestock feed

Brewing and malting (Canadian rye whiskey)

Food- bread, breakfast foods

Good fall cover crop that’s terminated pre-planing pr early spring

What is Triticale

Man-made interspecific cross between wheat and rye

There are tetraploid (4N), hexaploidy (6N), or octaploidy (8N)

Has a higher biomass then wheat and grains with higher protein- gluten quality is not the same

Used as forages

Key identifying features of cereal seedlings

Wheat- auricles are blunt and hairy, leaf sheath and blade are always hairy, and ligual is medium length

Rye- auricles are short and hairless, ligule is short

Barley- long, slender, and hairless auricles

Oat- no auricles, leaf blades twist counter clockwise

Triticale is similar to wheat but is blueish

What is Rice

Origin of Southeast Asia

C3 crop

Cultivated in Asia and drylands cultivated in the southern USA and California

Indica and japonica types

Aromatic rice include basmati and jasmine

90-180 days to mature

What is sorghum

Originates from sub-Saharan Africa

Used for feed for livestock and fodder as corn substitute, sweet sorghum cultivars for human consumption

C4 crop that is well adapted for dry areas with high temperatures

USA are 1 for proaction and Sudan and Nigeria are top acreage

What is Millet

Origin in East Asia and West Africa

Very tolerant to drought and high temperatures

Less productive then other cereals

What is wild rice

North American origin

Aquatic (90cm ideal water depth) snd annual plant

Shatter easily

Different lakes have different wild rice phenotypes because of the isolation of the populations

How does wild rice reproduce

With a triploid endosperm

Apomixis which is asexual seed production

Low germination rate

3N has 2 genomes from the mother and 1 genome from the father

How is wild rice production impacted

Can be impacted on insect damage, ergot, and heavy metal contamination

What are pseudo cereals

Buckwheat, quinoa, amaranth

Used as a cereal for human consumption

Botanically are not monocots which means they are not real cereals

What is Canola

45% oil and 20-25% protein

Doesn’t yield as much as wheat- 2nd most important crop in Canada in terms of production

The production is concentrated in Western Canada

Concentrated in the dark brown and black soil zones

Uses of Canola

Cooking oil, processed foods, livestock meal, industrial uses like inks and paints, cargil: omega-3 fish food, plant-based protein, and biodiesel

History of Canola

Production started during WWII when supply chain disruptions led to shortages

1978 Was the first trademark for canola to distinguish from rapeseed

Genetic Improvement Vs Genetic Modification

Genetic improvement= breeding. It uses conventional crosses, biotechnology like marker assisted selection and mutagenesis

Genetic modification is the insertion of genetic materials foreign to species traditionally with constitutive promoter (always on). Uses Crispr-Cas 9 technology which is a gene editing and allows it to be more precise

Brassica genetics and genetic relationships

Canola is not a botanical species which is a trademark for Brassica naps, B rapa, and B juncea species or hybrids

The trademarks need <2% eurcic acid and < 30mmol per g glucosinolates

Brassica napus aka Argentine canola is a tetraploid which is a cross between diploid brassica oleracea and brassica rapa

Comparison of Dietary Fats

Less saturated fats is better

Canola oil is 7% saturated fats, 28% polyunsaturated fats, and 62% monounsaturated fats

Flaxseed oil is 9% saturated fast, 67% polyunsaturated fats, and 18 monounsaturated fats. This is the most healthy because of the polyunsaturated but it can go bad quickly

Coconut oil is 87% saturated fats, 2% polyunsaturated fats, and 6% monounsaturated fats which is the most unhealthy

What is Biodiesel Stability

The replacement of diesel

The oxidation of biodiesel fuel depends on several factors:

• Length of fatty acids

• Proportion of unsaturated fatty acids

• Relative antioxidant content

• Metal contaminants

What are important diseases in canola

Clubroot which is a protist so fungicide seed treatment does not help

Blackleg

Sclerotinia stem rot

Verticillium stripe

Why are GMOs safe and not safe

Safe: assessed before approval and there are no signs on the market that they are dangerous to human health compared to non GMO foods

Not safe: too complicated to fully understand

What is Soybean

Important oilseed crop

Grows mostly in Quebec and Ontario in rotation with corn. There is some additional production in Manitoba

In Sask its a minor crop

Originates from Asia

20% oil and 36% protein

It is a leguminous crop that forms a symbiosis with Bradyrhizobia to fix nitrogen from the atmosphere

Well developed international trade- 3

1 source of edible oil in the USA

End uses of soybean

Edible oil, livestock meal, soy milk, tofu, tempeh, soya sauce, miso, plant-based protein, biodiesel

What is flax

Minor crop with production concentrated in Saskatchewan

Used for edible oil (flaxseed oil that is high in linolic acid), livestock feed, industrial oil (linseed oil for paints, solvents, and linoleum flooring), and fiber (linen)