Grade 10 - Modern Technology in Increased Food Production

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Grade 10 - Modern Technology in Increased Food Production Let's have fun

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sir awan

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 to open furrows in the earth.

designed to break up the parts and parcels of land that have been removed by the plough.

Designed to spray, where the liquid to spray out insecticide, fungicide or herbicide

is a machine to place the seeds on the seedbed

Designed to distribute fertilizer

Designed for packaging or packing cereal straw or other baled forage grasses (also called bales or alpacas)

Introduction

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 interchangeably.

Fertilizers have classified into following two group, depending on the number of nutrients available in them.

Complex/ compound fertilizers

Straight fertilizers

Introduction

Straight fertilizers

• 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/compound 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) fertilizers.

• 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 population. Grouped by their target organism

Insecticide, Herbicide, Fungicide, Rodenticide

85% of pesticides worldwide used for Agriculture.

“Ideal Pesticides” Narrow-Spectrum = kill only target

organism. 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) Inorganics (Minerals)

Contain lead, mercury, and arsenic Very persistent & bioaccumulate

Organics (Botanicals) Plant-derived Break down readily

Post-1940s (Second-generation pesticides) Synthetic Botanicals

Made by altering natural botanicals Ex: dichlorodiphenyltrichloroethane (DDT)

INSECTICIDES : Classified by chemical structure

Chlorinated Hydrocarbons = organic CMPDs + Cl Broad-spectrum, persistent Most are banned (DDT, endosulfan, etc) Rachel Carson: Silent Spring

Organophosphates = organic CMPDs + P more poisonous than most others not persistent, so they’ve replaced most

chlorinated hydrocarbons

Carbamates = broad-spectrum, derived from carbamic acid Less toxic to mammals (Carbaryl, Aldicarb)

HERBICIDES Are pesticides used to kill unwanted plants Classified by how they act & what they kill Selective Herbicides = kill only certain

types of plants Broad-leaf Herbicides

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

Grass Herbicides Nonselective Herbicides = kill all

vegetation

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, & Agent Orange

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, soft-tissue cancers Bioaccumulated in fish = very high levels in

Vietnamese people

Artificial selection is the process by which heritable traits favored by human actions become more common in successive generations.

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, Brassica oleracea

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.