Response of Selected Potato Genotypes to Natural Virus Infection in the Field

Abstract

Potato viruses are one of the major biotic factors causing high yield losses in potato production fields. In contrast to other disease causing pathogens, potato viruses’ lack well documented chemical control strategy and hence difficult to control once established in the field. The aim of the study was to assess the reaction of different potato genotypes to natural virus infection in the field. The present study was carried out on 12 potato genotypes (7 CIP clones and 5 commercial varieties) at the Field Station of the University of Nairobi, Upper Kabete campus Kenya in two potato growth seasons. A Randomized Complete Block Design (RCBD) of 4 replications was adopted with 12 treatments. Data was collected on percent crop emergence, disease incidence, growth and yield performance. At the end of season 2, tubers were sampled randomly per genotype and tested for presence of viruses using CIP DAS-ELISA kit. Analysis of variance on different parameters revealed varied response of each genotype to virus infection in the field in both seasons. Four potato viruses: PVS (67%), PVY (20%), PLRV (12%) and PVM (7%), were detected infecting tested potato tubers either as single or as multiple infections. The results revealed that four clones: 392797.22, 393371.157, 398190.200 and 397073.7 had high levels of tolerance to virus infection. Therefore further studies should be done to understand whether they possess quantitative or qualitative resistant traits to specific potato viruses and other biotic factors.