EPPO Global Database

EPPO Reporting Service no. 01 - 1974 Num. article: 1974/06

Potato Spindle Tuber in the Commonwealth Potato Collection

Potato Spindle Tuber the Commonwealth Potato Collection1)

Potato spindle tuber virus (PSTV) has recently been found in some lines of the Commonwealth Potato Collection (CPC). This discovery is important both for the United Kingdom, since the disease is not known to occur in commercial potato stocks there, and generally, because occurrence in other gene banks is possible.

The CPC, previously maintained at the John Innes Institute, at Hertford, England, was transferred to the Scottish Plant Breeding Station, Pentlandfield, Roslin, Midlothian, Scotland, in 1967. The collection now consists of approximately 1,200 lines maintained as seed and grown as required under glass. New accessions received as tubers are kept in quarantine until seed can be obtained.

When the collection was transferred to Scotland testing of tuber lines was intensified to determine virus content. PSTV was detected in two accessions, Solanum commersonii Dun. and S. speganii Bitt. The identity of the original isolate was confirmed by Dr W.B. Raymer, USDA2), as a severe strain of PSTV. This coincided with the conclusive findings of SINGH (1970)3) that PSTV can be transmitted in the true seed of Solanum. Testing of the CPC was then extended to the maintenance collection of seed lines and PSTV was consequently found in some others. Isolates are grouped according to severity of reaction on test plants but recent experimental work suggests that some isolates, particularly in the "intermediate" reaction group, may consist of more than one strain.

A large proportion of the CPC has now been tested and found to be apparently free from PSTV, but results are inconclusive in some instances because of the difficulties in detecting mild strains. Testing of the remainder will be completed shortly. In the meantime, when seed is requested by breeders in other countries, particularly in respect of lines which have not yet been tested, the phytosanitary authorities of the importing countries are informed of the risks. All further accessions to the CPC will be subjected to exhaustive quarantine zests.

It seems unlikely that the discovery will prove peculiar to the CPC. Curators of other potato gene banks are therefore warned that infection may exist in the collections they maintain, and the need for careful testing is indicated. The risk of spread is great in view of the world-wide distribution and exchange of genetic material, and the seed and tuber transmissibility of this disease.

Information on the detection of PSTV in the Commonwealth Potato Collection will be published shortly. In the meantime a bibliography containing all relevant references to the disease is available on request.
1) R.H. CAMMACK & P.S. HARRIS, Department of Agriculture and Fisheries for Scotland, Edinburgh (United Kingdom).
2) USDA : United States Department of Agriculture.
3) SINGH, R.P. (1970). Seed transmission of potato spindle tuber virus in tomato and potato. Amer. Potato J. 47 : 225-227.


Dept. of Agriculture & Fisheries for Scotland, Edinburgh (1974-03-06)