Seed Technology_ Purity Analysis Packet

How many volumes are there in the AOSA Rules for Testing Seeds

4 volumes

Why has seed testing been developed

we want information on seed conditioning, seed merchandising, seed planting, and seed control purposes

What must you do if you deviate from the rules laid out in the books

You must make note of the deviation on the seed lot’s report

What 3 things should the laboratory analysis determine for every seed sample

• the purity composition

• the noxious weed seeds per unit weight

  • the percent germination of pure seed

Definition of Kind

one or more related species or subspecies that singly or collectively is usually known by one common name

Definition of Seed Unit

the structure regarded as a seed in planting practices and in commercial channels

Definition of working samples

1) Bulk Examination: the sub-sample taken from the submitted sample on which a bulk examination is performed

2) Fungal Endophyte: the sub-sample of either seed or tillers taken from the submitted sample on which the fungal endophyte test is performed

3) Germination: the sub-sample taken either from the pure seed portion of the purity analysis or directly from the submitted sample on which the germination test is performed

4) Purity Working Sample: the sub-sample taken from the submitted sample on which the purity test is performed

5) Noxious Weed Seed: the sub-sample taken from the submitted sample on which the noxious weed seed test is performed

6) Seed Moisture Determination: the sub-sample taken from the submitted sample on which the seed moisture test is performed

What are the Seed Formats and their Characteristics

• Coated or Encrusted - weight increase

• Film Coated - minimal weight, no dust, safer to handle

• Inoculated - has a coating of Rhizobium sp.

• Pelleted - improved plantability and singulation, weight increase

• Raw - free of any chemicals

• Treated - has a coating of some sort, used to reduce or control certain diseases, insects, or pests

What are the seed coating ingredients?

Binders: liquid

Fillers: powders

Active Ingredients: protectants, nutrients, adjuvants, colors and tracers, etc.

What machines do you use to coat the following:

• Film

• Encrusting

• Pelleting

Film: Fluidised bed

Encrusting: Rotary Coater

Pelleting: Rotating Pan

Seed Coatings categorized by weight

Film: less than 10% of seed weight

Encrusting: 100-500% seed weight

Pelleting: seed shape becomes impossible to distinguish

How many times should a sample be run through a divider to mix well

At least 3 times

How are Gamet dividers driven

Electicity

How are Boener dividers driven

Gravity Fed

What are Riffle dividers used for

Chaffy seeds and soybeans

the better ones can do many varieties

What is the pie method

Hand splitting a sample due to lack of a machine or a very small sample

example: grasses that won’t go through a divider well