Eradication of Soil Pests and Pathogens by Cultivation of Non-Hosts
Vegetable and Forage Crops Production Research
2012 Annual Report
1a.Objectives (from AD-416):
Identify cultivable plant species that are non-hosts for certain pests and pathogens common in the Pacific Northwest and achieve a measure of control or eradication without use of chemicals.
1b.Approach (from AD-416):
Test different plant species for host range against a panel of pests and diseases of the Pacific Northwest. Hosts should demonstrate egg hatching induction, but lack of successful parasitism and reproductions for nematodes, lack of successful initial inoculation events and propagation in the case of fungi. Successful candidates will be examined for ease of cultivation, flowering, seed production, root mass and rooting depth.
We evaluated the possibility that Solanum sisymbriifolium (Ss) would be able to clean up a field infected with tobacco rattle virus (TRV), as identified in sub-objective 1.B. of the related in-house project, "Develop germplasm with resistance to pests and diseases, establishing effective and efficient screening protocols, determining range of expression, inheritance, heritability, and discover molecular markers, while mapping genetic factors where possible and useful". Our first findings indicated that stubby root nematode is able to transmit TRV to the roots of Ss in 100 % percent of the cases. We will follow up on this and determine whether stubby root nematode can acquire TRV from the roots of Ss. The breeding line PA99N82-4 has introgressed genetic materials from Solanum bulbocastanum. It is resistant to root multiplication of race 1 of Columbia root-knot nematode (CRKN). Race of CRKN P1-1, a resistance breaking pathotype should be able to multiply on the roots. We obtained unexpected findings. Comparing to Russet Burbank, N82-4 produced a pronounced reduction of live nematodes by the end of the season. Hence the resistance in this breeding line not only protects it from nematode damage but also lowers the nematode population to a level lower than the initial populations. In other words, it cleans up of the field of CRKN.