FAQ Purity Committee
Purity Testing
| Request | PSD: understanding of the 50% of Pure seed definition |
| ISTA Chapter | 3 |
| Reference | 3.2.1 Pure seed …. 1. The following structures ……… 1. Intact seed units 2. Pieces of seed units larger than one-half their original size. |
| Recommendation for action | The basis is the size of the seeds, disregarding whether an embryo is present or not. The reason is the best possible uniformity in the application of this rule among ISTA labs. It is regarded as easy and clear for everybody to estimate the original size of a seed and then apply the 50% Rule. To decide about pieces of seed containing pieces of embryos and if they will germinate or not, will be less uniform from analyst to analyst. The agricultural value of broken seeds with/without embryo/pieces of embryo is then determined in the germination test. |
| Links |
Purity Testing
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PSD: understanding of the 50% of Pure seed definition
ISTA Chapter 3 Reference 3.2.1 Pure seed
….
1. The following structures ………
1. Intact seed units
2. Pieces of seed units larger than one-half their original size.Recommendation for action The basis is the size of the seeds, disregarding whether an embryo is present or not. The reason is the best possible uniformity in the application of this rule among ISTA labs. It is regarded as easy and clear for everybody to estimate the original size of a seed and then apply the 50% Rule. To decide about pieces of seed containing pieces of embryos and if they will germinate or not, will be less uniform from analyst to analyst. The agricultural value of broken seeds with/without embryo/pieces of embryo is then determined in the germination test. Link List Link 1: Test
Purity Testing
-
PSD: understanding of the 50% of Pure seed definition
ISTA Chapter: 3
Reference:
3.2.1 Pure seed
….
1. The following structures ………
1. Intact seed units
2. Pieces of seed units larger than one-half their original size.Recommendation for action
The basis is the size of the seeds, disregarding whether an embryo is present or not. The reason is the best possible uniformity in the application of this rule among ISTA labs. It is regarded as easy and clear for everybody to estimate the original size of a seed and then apply the 50% Rule. To decide about pieces of seed containing pieces of embryos and if they will germinate or not, will be less uniform from analyst to analyst. The agricultural value of broken seeds with/without embryo/pieces of embryo is then determined in the germination test.
Link List