Grade 10 - Modern Technology in Increased Food Production
a very useful agricultural machine, with wheels or designed
to move easily on the ground and pulling power enabling
successful agricultural work, even in flooded fields. Its main
function is to cultivate the soil
Operated by handles, can work in strong fields, but is
preferably used in construction of gardens
a powerful engine agricultural machine, comb cutter to cut
the plants mature grain and a long rake that goes before the
machine and rotates about a horizontal axis.
Designed for packaging or packing cereal straw or other
baled forage grasses (also called bales or alpacas)
a manufactured product containing one or more
essential plant nutrients
in amounts without carrying any harmful
substance above permissible limits.
Many prefixes such as synthetic, mineral,
inorganic, artificial or chemical are often used to
describe fertilizers and these are used
Fertilizers have classified into following two
group, depending on the number of nutrients
available in them.
• Straight fertilizers contain one of the three major
nutrients N, P or K.
• that contain and are used for one major nutrient as
opposed to multinutrient fertilizers.
• For secondary nutrients, these include products containing
elemental S, magnesium sulphate, calcium oxide, etc.
• In the case of micronutrients, borax, Zn and Fe and
sulphate salts of micronutrients are straight fertilizers.
• Complex or compound fertilizers contain at least two out of
the three major nutrients.
• These include both two-nutrient (NP) and three nutrient (NPK)
• These are also referred to as maltinutrient fertilizers, but do
not include fertilizer mixture or bulk blends as no chemical
reaction is involved.
PEST = any organism that interferes in
some way with human welfare or activities.
PESTICIDE = toxic chemicals used to
reduce the size of and control the pest
Grouped by their target organism
85% of pesticides worldwide used for
“Ideal Pesticides ”
Narrow-Spectrum = kill only target
Breaks down easily into safe materials
Does not move around in the environment.
“Non-Ideal Pesticides ”
Broad-Spectrum = kill more than just the target.
Persistent or Can degrade into other
CMPDs (Chronic Myeloproliferative
Diseases) that can be more dangerous
Move around in the environment.
Pre-1940s (First-generation pesticides )
Contain lead, mercury, and arsenic
Very persistent & bioaccumulate
Break down readily
Post-1940s (Second-generation pesticides )
Made by altering natural botanicals
Ex: dichlorodiphenyltrichloroethane (DDT)
INSECTICIDES : Classified by chemical structure
Chlorinated Hydrocarbons = organic CMPDs + Cl
Organophosphates = organic CMPDs + P
Most are banned (DDT, endosulfan, etc)
Rachel Carson: Silent Spring
more poisonous than most others
not persistent, so they’ve replaced most
Carbamates = broad-spectrum, derived from
Less toxic to mammals (Carbaryl, Aldicarb)
Are pesticides used to kill unwanted plants
Classified by how they act & what they kill
Selective Herbicides = kill only certain
types of plants
2,4-D & 2,4,5-T common in 1940s
2,4,5-T banned by EPA (Environmental Protection
Agency) in 1979 due to possible harmful side effects
realized after its use in the Vietnam War
Nonselective Herbicides = kill all
VIETNAM WAR & HERBICIDES
US used mixtures of herbicides to kill vegetation in
S.Vietnam to expose hiding places & destroy crops
planted by Vietcong: Agent White, Agent Blue, &
Negative environmental impacts:
Mangrove forests & hardwood forests destroyed
Harmed ecology & economy of S.Vietnam
Negative health impacts:
Agent Orange = 2,4-D & 2,4,5-T combined.
Created highly toxic Dioxins during creation
Birth defects, stillbirths, female reproductive disorders,
Bioaccumulated in fish = very high levels in Vietnamese
Artificial selection is the process by which
heritable traits favored by human actions
become more common in successive
Also called “selective breeding.” Very well known
to farmers and breeders, artificial selection is
how they harness evolution to produce the
varieties of plants and animals that they want.
Artificial selection can be intentional, or
unintentional on our parts.
All of our domesticated species - pets, crops,
farm animals - evolved through artificial
selection. In many cases, it was intentional.
Corn, or maize, is the result of domestic
breeding of teosinte by Mesoamerican famers
~9,000 years ago.
Artificial selection applied to the wild mustard,
There have also been many cases where we’ve
imposed a selective pressure on a population
without even knowing it. These cases can also
be called artificial selection.
Most cereal crops were unintentionally developed
12,000 years ago. There’s no evidence that the first
farmers premeditated and decided to breed certain
plants in order to keep and enhance their desired
traits, they just kept plants because they liked them.