Screening for Gpa5 gene resistance to the potato cyst nematode Globodera pallida

TISSUE TYPE: Leaf material, tubers or sprouts

Additional information:

This marker allows us to detect G. pallida resistance coming from the Gpa5 gene originating from Solanum vernei (clone AM78.3778).

The marker is very useful for screening lines that have Innovator in its pedigree.  This also includes any resistant progeny of Innovator e.g. Eurostar, Performer, Panther, Ambassador, Amanda etc. that may have been used as a parent.

The HC marker has been screened against several hundred varieties and clones and phenotypic data and genotypic compared. 

We find very good correlations between the presence of the HC marker and very low cysts numbers (~0-5 cysts) from phenotypic tests.

We are aware of a few false positives with a handful of varieties/lines that have S. vernei parentage coming from UK germplasm.  However, with having this knowledge and if we understand the pedigree of the clone being tested, we find the marker to be very beneficial.

If you want material screened with the HC marker and Gpa5 resistance is expected in the pedigree, please check with us to see if the parents have already been screened and if not, if you can provide parental material, we can screen them as well to improve accuracy of the results. We will be happy to test any parents that haven’t already been tested and that are “NL named varieties” at no charge (within reason) with the HC marker as it is of benefit to continue to add to the James Hutton Limited data set. 

If you do a combined canister/HC test this is also useful when working with clones that potentially have Gpa 5 gene resistance (Innovator type) or H3 gene resistance (Vales Everest type) as the HC marker will be able to tell you which source of resistance you have and should correlate well with the cyst counts from the canister test, with H3 gene resistance counts generally being higher (~5 -15 cysts) than Gpa5 resistance counts (~0-5 cysts).