Demonstrate knowledge of safety with Agrichemicals 21544 Level 2 : Credits 3

Throughout history, the onslaught of pests, diseases and weeds has caused great destruction to crops and livestock that have been produced by man. These problems have to a large degree been overcome in the last 50 years by the development of agricultural chemicals. Today the range of agrichemicals available to huge. To control a pest, disease or weed an agrichemical must be toxic to some degree, the toxicity will be confined to the pest, disease or weed. Handling agrichemical therefore involves an element of risk to humans, and other animals/plants https://www.youtube.com/watch?v=IoNgT7qO12Y https://www.youtube.com/watch?v=C6Ay2SvfN_w

Types of Agrichemicals Agrichemicals can be divided into the following groups: Fungicides – these are used to control fungi Herbicides – these are used to control unwanted plants Insecticides- these are used to control insects Miticides - these are used to control mits Nematicide - these are used to control nematodes Drenches - these are used to control internal and external parasites of livestock Plant growth regulators- these are used to alter the growth of crop plants Agrichemicals all have different modes of action. A mode of action is the way in which agrichemicals works or is effective.  

Insecticides Contact – these can penetrate the bony surface of an insect either by direct contact with a spray droplet or by the insect walking on a surface where there is an insecticide droplet. Stomach poison – these have to be ingested eaten by the insect for them to be effective. Systemic – these agrichemicals are absorbed into the sap stream of the plant, either through the roots or leaves, and are translocated to other parts of the plant. They affect nsects when the insect bite or chew or suck sap from the plant

Fungicides Protectant- to be affective, these agrichemicals must be in place on the surface before the fungal spore land on the surface. The fungicide then prevents the spore from germinating and penetrating into the plant. Eradicant – the agrichemicals are effective when applied to the plant that already is infected. They are often translocated throughout the plant

Herbicide Residual these interfere with the germination of weed seeds,so they need to be applied before the weeds germinate Contact- these kill plant tissue and only control the aboveground parts of weeds Systemic- these are absorded by the weeds, translocated through the whole plant, killing the whole plant

Agrichemical Names Most agrichemicals have three names:   A chemical name A common name A trade name A chemist would recognise an agrichemical by its chemical name. This is made up of the chemicals that are included in the agrichemical. The chemical name is often too long and too complicated to be used regularly, so common names are given to agrichemicals. Common names( which are approved by national organisations) are used throughout the world. Makers of agrichemicals usually give their product a trade name, such as “Roundup” or “tordon”. This can cause misunderstandings as several makers may manufacture the same agrichemical, but each maker will give it a different trade name.

Formulations The chemical ( or chemicals) in an agrichemical that enable the agrichemical to control a pest, disease or weed is called the active ingredient. Depending on the form that the agrichemical is on, the active ingredient (a.i) present will be shown as either:   Grams per liter; g/l ( for liquids) Grams per kilogram; g’kg (for solids) Agrichemicals commonly come in three forms;

finely divided powders that are not soluble in water Solids Powders Water Soluble finely ground a.i which easily dissolves in water, easy to measure and mix with no settling Water insoluble does not easily dissolve in water, requires constant mixing to prevent settling. Eg Dusts finely divided powders that are not soluble in water Wettable powders finely divided powders that form a stable suspension in water Colloidal powders-very finer than wettable powders and form a non-settling suspension in water. Granules The active ingredient is mixed with clay into a granule, dissolves when ,mixed with water. They are also called pellets or prills. There are two types; Dispersable break down quickly especially on contact with water.  Non-dispersible breaks down relatively slowly. Baits The active ingredient is mixed with a food or other material that will attract pests.

Gases Liquids Aqueous Concentrates These are mixtures of active ingredient and water, and form a true solution when mixed with water.   Non- Aqueous Concentrates These are mixtures of active ingredient and oil or another solvent and are never mixed with water Emulsifiable Concentrate These are mixtures of active ingredient and oil/solvent which are mixed with water to form an emulsion. These are easily mixed and applied. Suspension Concentrates These are a mixture of a finely ground insoluble active (solid particles), a dispersant and a thickener Colloidal Suspensions These are similar to suspension concentrates but the solid particles are much finer. https://www.youtube.com/watch?v=k2-9utkVq4k Gases Fumigant These are mixtures of active ingredient and other substances which, when released, produce a gas Aerosols These contain the active ingredient mixed with a liquefied gas which, when released, forms a fine mist of very finely divided solid and/or liquid particles that can remain suspended in the air for several hours. Smoke These are preparations of active ingredient and a heat producing material which, when it burns, spreads the active ingredient as a vapour

Adjuvants https://www.youtube.com/watch?v=FBBo-sYCmXs

Toxicity https://www.youtube.com/watch?v=T27XIpmEGcI https://www.youtube.com/watch?v=25EPdi_WjZ8

Withholding and Waiting Periods

Codes of Practice

Handling Chemicals

Handling Chemicals