Stacking Resistance Genes in Multiparental Interspecific Potato Hybrids to Anticipate Late Blight Outbreaks

Elena V Rogozina,Mariya P Beketova,Oksana A Muratova,Emil E Khavkin,Mariya A Kuznetsova

doi:10.3390/agronomy11010115

Elena V Rogozina, Mariya P Beketova + Show 3 more

Open Access

https://doi.org/10.3390/agronomy11010115

Copy DOI

Abstract

Stacking (pyramiding) several resistance genes of diverse race specificity in one and the same plant by hybridization provides for high and durable resistance to major diseases, such as potato late blight (LB), especially when breeders combine highly efficient genes for broad-spectrum resistance that are novel to the intruding pathogens. Our collection of potato hybrids manifesting long-lasting LB resistance comprises, as a whole, the germplasm of 26 or 22 Solanum species (as treated by Bukasov and Hawkes, respectively), with up to 8–9 species listed in the pedigree of an individual hybrid. This collection was screened with the markers of ten genes for race-specific resistance to Phytophthora infestans (Rpi genes) initially identified in S. demissum (R1, R2, R3a, R3b, and R8), S. bulbocastanum/S. stoloniferum (Rpi-blb1/ Rpi-sto1, Rpi-blb2, Rpi-blb3) and S. venturii (Rpi-vnt1). The hybrids comprised the markers for up to four-six Rpi genes per plant, and the number of markers was significantly related to LB resistance. Nevertheless, a considerable portion of resistance apparently depended on presently insufficiently characterized resistance genes. Bred from these multiparental hybrids, the advanced lines with the stacks of broad-specificity Rpi genes will help anticipate LB outbreaks caused by rapid pathogen evolution and the arrival of new pathogen strains.

Highlights

Persistent and unrelenting, late blight (LB) of potato (Solanum tuberosum L.) caused by the oomycete Phytophthora infestans (Mont.) de Bary levies a permanent tax on potato growers: up to $10 billion is lost annually as direct crop losses and costs of chemical protection; the losses rise dramatically in the years of epidemic disease development [1,2,3].The most economical and environment-friendly way to effectively contest and contain LB is to breed new cultivars with durable resistance
50 hybrids and cultivars were assessed for their LB resistance in the span of seven years (2014–2020)
High and long-lasting LB resistance is a major prerequisite for sustainable potato production

Summary

Introduction

Persistent and unrelenting, late blight (LB) of potato (Solanum tuberosum L.) caused by the oomycete Phytophthora infestans (Mont.) de Bary levies a permanent tax on potato growers: up to $10 billion is lost annually as direct crop losses and costs of chemical protection; the losses rise dramatically in the years of epidemic disease development [1,2,3].The most economical and environment-friendly way to effectively contest and contain LB is to breed new cultivars with durable resistance. Wild potatoes readily supply the necessary germplasm, and multiple Rpi genes have already been introgressed into marketable cultivars by the marker-assisted sexual and somatic hybridization or with the technologies of genetic engineering [3,5,6,7,8,9,10,11] This resistance is gained slowly and with hard labor—and can be disappointedly lost, sometimes within few years, due to the rapid evolution of P. infestans genome and the arrival of new pathogen strains with novel repertoire of (a)virulence genes (Avr genes) [1,2,3,6,10,11]

Methods

Results

Conclusion