Seed Health Testing

SGS can help you diagnose plant pathogens affecting your crops so you can make informed decisions on how to treat them.

SGS MWSS is an accredited by the National Seed Health System (NSHS) and also by the International Seed Testing Association (ISTA).  SGS MWSS offers NSHS approved test for the following pathogens:

SGS MWSS is also approved for seed sampling for phytosanitary laboratory testing and visual inspections.   

Below are examples of the test available, but many other pathogens are available.

Types of Tests
Blotter – Fusarium, Alternaria, Phomopsis, Cercospora (Frogeye)

Seeds are typically surface sterilized with a dilute hypochlorite solution and planted on 6x9in blotters. These are incubated and observed for 7-10 days. Fungal growth is recorded and confirmed with microscopic examination.  

Culture Plate – Ascochyta, Cercospora (purple blotch), Botryis cineria, Alternaria
Seeds are typically surface sterilized with a dilute hypochlorite solution and placed in 10mm culture plates with growth media. These are incubated and observed for 7-10 days. Fungal and/or bacterial growth is recorded and confirmed with microscopic examination.

ELISA – Soybean mosaic virus, bean pod mottle, other viruses
Seeds are typically ground then extracted with a standard extraction buffer. The solution is then collected and analyzed using 96well plated coated with specific antibodies. The plate is read on a an ELISA plate reader alongside positive and negative controls.   

Wash test – Ustilago maydis (Loose Smut), Soybean Cyst Nematode
Seeds are washed for an extended period and resulting solution is observed under a microscope and any present pathogens are recorded.

PCR – Acidovorax avenae pv citrulli (Bacterial Fruit Blotch)
Seeds are extracted for contaminating pathogen DNA. Solution is examined by PCR alongside positive and negative controls.

Soybean blotter test for Phomopsis species.		Sunflower seeds with Aspergillus infection on culture plates.		Ustilago nunda (Loose Smut in wheat)