Reduced phloem uptake of Myzus persicae on an aphid resistant pepper accession

Abstract

BackgroundThe green peach aphid (GPA), Myzus persicae, is economically one of the most threatening pests in pepper cultivation, which not only causes direct damage but also transmits many viruses. Breeding aphid resistant pepper varieties is a promising and environmentally friendly method to control aphid populations in the field and in the greenhouse. Until now, no strong sources of resistance against the GPA have been identified. Therefore the main aims of this study were to identify pepper materials with a good level of resistance to GPA and to elucidate possible resistance mechanisms.ResultsWe screened 74 pepper accessions from different geographical areas for resistance to M. persicae. After four rounds of evaluation we identified one Capsicum baccatum accession (PB2013071) as highly resistant to M. persicae, while the accessions PB2013062 and PB2012022 showed intermediate resistance. The resistance of PB2013071 resulted in a severely reduced uptake of phloem compared to the susceptible accession, as determined by Electrical Penetration Graph (EPG) studies. Feeding of M. persicae induced the expression of callose synthase genes and resulted in callose deposition in the sieve elements in resistant, but not in susceptible plants.ConclusionsThree aphid resistant pepper accessions were identified, which will be important for breeding aphid resistant pepper varieties in the future. The most resistant accession PB2013071 showed phloem-based resistance against aphid infestation.Electronic supplementary materialThe online version of this article (10.1186/s12870-018-1340-3) contains supplementary material, which is available to authorized users.

Overview of Biotic Stresses in Pepper (Capsicum spp.): Sources of Genetic Resistance, Molecular Breeding and Genomics

“…Sun and colleagues [247], screened 74 pepper accessions, belonging to C. annuum, C. frutescens, C. chinense and C. baccatum, for resistance to GPA. The authors identified three C. baccatum accessions with high (PB2013071) or intermediate resistance (PB2013062 and PB2012022) and elucidated possible mechanisms of aphid resistance.…”

“…The authors identified three C. baccatum accessions with high (PB2013071) or intermediate resistance (PB2013062 and PB2012022) and elucidated possible mechanisms of aphid resistance. The highly resistant genotype resulted in a severely reduced uptake of phloem, a significant callose deposition due to feeding of GPA, and in the accumulation of ROS (reactive oxygen species) [247].…”

Resistance to greenbugs in the sorghum nested association mapping population

“…2). Several previous studies have shown that the reduced phloem sap ingestion from the host plants correlates with the enhanced resistance to daraju et al 2007;Koch et al 2015;George et al 2017;George and Lapointe 2018;Sun et al 2018). Besides the chemical substances present in the phloem sap of resistant plants, it is possible that the presence of morphological/physical barriers on host plants can also contribute to difficulties in stylet penetration and sustainment for sapsucking insect feeding (Baldin et al 2017;George et al 2017).…”

Aphid resistance in Capsicum maps to a locus containing LRR-RLK gene analogues

“…1 3 promising alternative. Resistance to aphids not only reduces the size of the aphid population on pepper (Frantz et al 2004;Sun et al 2018), but may also decrease the percentage of plants infected with viruses (Radcliffe and Ragsdale 2002). In several plant species, quantitative trait loci (QTLs) for resistance against aphids have been detected.…”

“…In a previous paper, we have described the screening and characterization of several sources of GPA resistance in Capsicum species (Sun et al 2018). Three accessions of Capsicum baccatum were shown to be resistant or intermediately resistant to GPA by negatively affecting aphid survival and reproduction.…”