Crop Genebank Knowledge Base

Crops

Forage grasses

Conservation

Seed bank

Health diagnosis

Health diagnosis of forage grass genetic resources

Contributors to this page: ILRI, Addis Ababa, Ethiopia (Jean Hanson, Juvy B. Cantrell, Janice Proud); CIAT, Cali, Colombia (Maritza Cuervo); Bioversity International/ILRI, Addis Ababa, Ethiopia (Alexandra Jorge).

List of pests and diseases of quarantine importance

Click here for more detailed outputs from the page of the safe movement of germplasm, on this website.

Fungi

Ustilago kamurensis (Kenya).

Virus

Elephant grass mosaic virus (EGMV).
Johnson grass mosaic virus (JGMV).

Phytoplasma

Napier stunt (East Africa).

Click the forage grasses health table for specific species information about health diagnosis methods to detect some of these diseases.

The text for this flip book was extracted from: Rao NK, Hanson J, Dulloo ME, Ghosh K, Nowel D and Larinde M. 2006. Manual of seed handling in genebanks. Handbooks for Genebanks No. 8. Bioversity International, Rome, Italy. 147pp.

Options for testing procedures

Recommended methods to detect the presence of each pest or disease:

Virus (ELISA, TBIA).
Fungi (Blotter test, grow on media and isolation and identification).
Phytoplasma (NASH, PCR methods).

Testing intervals/seasons

Testing before material goes into the genebank or to the field is important to reduce transfer of diseases or pests.

Virus

Test seedlings before transfer to the field for regeneration or during regeneration, and rogue out infected material.

Fungi

Test seed lots on entry to genebank.

Phytoplasma

Test young and tender leaves and rogue out infected material.

Recording information during health diagnosis

The following information should be recorded for each health diagnosis step:

Accession number (an ID number).
Lot number (an ID number).
Genus (genus name of the plant, entered in full).
Species (species name of the plant, entered in full).
Date of test (the date that the test was commenced).
Number of replications (the number of replicates in the test).
Number of seeds per replication (the number of seeds in each replicate of the test).
Pre-treatments (pre treatments used for the test).
Media (the media for the test) (e.g. for fungi).
Material (plant part used, if not seeds).
Pathogen tested (name of pathogen tested).
Test method (method used).
Percentage infection (% of seeds or plants infected).

References and further reading

Albrechtsen SE. 2006. Testing Methods for Seed-Transmitted Viruses: Principles and Protocols. CABI Publishing, Cambridge, USA. pp. 268.

Plant Biosecurity, Biosecurity Australia 2000. Viruses, Phytoplasmas and Spiroplasmas of Clonal Grasses and Their Diagnosis. Consultancy report. Available from: http://www.daff.gov.au/__data/assets/word_doc/0020/24761/consul_rpt_clonal.doc. Date accessed: 16 Jan 2011.