Influence of a Native Solanum tuberosum ssp. andigenum Potato Variety on Management of the Guatemalan Potato Moth in the Venezuelan Andes

Abstract

Smallholder farmers in the Venezuelan Andes have observed that native Solanum tuberosum ssp. Andigenum (Andigena) potato varieties are less susceptible to damage from the invasive pest, Tecia solanivora P. (Lepidoptera: Gelechiidae) than improved varieties. Surprisingly, the value of using Andigena varieties in the management of T. solanivora remains unexplored. Field trials were established in Misinta, Venezuela, to assess T. solanivora damage on potatoes from an Andigena variety, ‘Imilla negra’, and two improved varieties, ‘Andinita’ and ‘Unica’. The influence of intercropped Imilla negra varieties on T. solanivora damage and marketable yield in neighboring improved potato varieties was also assessed. While Imilla negra had significantly less T. solanivora damage per plant (percentage of damaged tubers) and per tuber (number of larval exit perforations) than Andinita and Unica in monoculture trials, intercropped Imilla negra did not reduce T. solanivora damage or increase undamaged tuber yield of improved varieties in polycultures. The results support Andean farmer knowledge on Andigena potato varieties and suggest that the proper incorporation of these varieties into potato cropping systems might be a promising strategy in managing T. solanivora. Nevertheless, further evaluation extending beyond a single growing season is needed to validate the findings of this study over time, as year to year variability in environmental conditions can alter host plant preference in herbivorous insects.