Lesion nematode suppression with the butte potato and relationships to verticillium wilt

Abstract

Field studies conducted over a 5 yr period to compare the effect of continuous cropping of several potato clones (Butte, Russet Burbank, Targhee, A66107-51, and A68113-4) showed Butte to be highly resistant to Pratylenchus neglectus while being highly susceptible to Verticillium dahliae. This was further evidenced during the 6th yr when Russet Burbank was cropped over all plot-locations. Populations of P. neglectus were shown to be significantly less (0.05 P) in both soil and roots when Russet Burbank was grown over sites previously cropped with the Butte potato than over site-locations cropped by either Russet Burbank, Targhee, A66107-51, or A68113-4. Additional field and greenhouse studies corroborated the high degree of resistance of Butte to Pratylenchus spp. In addition to P. neglectus resistance, a greenhouse investigation also showed resistance to P. penetrans. A field study designed to compare the effects of Butte with nematicides showed that Butte reduced P. neglectus populations in both soil and roots when compared with Russet Burbank. This degree of reduction was equivalent to the effects of either of two systemic nematicides (aldicarb and isofenphos) at 3.4 to 4.0 kg a.i./ha, respectively. Results demonstrate biological control with the Butte potato clone for P. neglectus suppression. Although populations of P. neglectus were reduced by either nematicides or Butte, wilt severity was higher with Butte than Russet Burbank. Results showed wilt suppression and P. neglectus reduction with treatments of either nematicide, while having no significant effect on the colonization of potato stems by V. dahliae. © 1992 Springer.