Molecular mapping of a gene conferring resistance to Phytophthora capsici Leonian race 2 in pepper line PI201234 (Capsicum annuum L.)

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

“…The results of the two studies suggest that gene suppression renders the plants unable to activate the resistance response increasing susceptibility. In 2016, genomic studies allowed to identify over a thousand genes differentially expressed in the resistant line PI201234 among them, 211 were involved in defense responses based on the gene annotations [75]. Validation tests in the resistant Qiemen line, allowed to identify seven genes responsible for many functions related to the prevention of infection (cell wall modification, symptom development, and phytohormone signaling pathways and phytoalexin biosynthesis).…”

“…Validation tests in the resistant Qiemen line, allowed to identify seven genes responsible for many functions related to the prevention of infection (cell wall modification, symptom development, and phytohormone signaling pathways and phytoalexin biosynthesis). The accession PI201234 was used to develop a population of 794 F 2 individuals by crossing to the susceptible Shanghaiyuan variety [75]. A single dominant gene, CaPhyto, on Chr 5 and two candidate genes, Capana05g000764 and Capana05g000769, were found to underly the resistance to race 2.…”

“…A microsatellite marker (ZL6726) positioned at a distance of 1.5 cM from CaPhyto, was validated to be reliable for selecting phenotypes of resistance to the same P. capsici race. Several other molecular markers associated with resistance to P. capsici have been reported in chile pepper for more rapid selection [51,64,66,68,72,75].…”

Development of Clustered Resistance Gene Analogs-Based Markers of Resistance toPhytophthora capsiciin Chili Pepper

“…To date, several markers linked to the major resistance QTL in pepper have been developed including restriction fragment length polymorphisms (RFLPs), randomly amplified polymorphic DNA (RAPD), amplified fragment length polymorphisms (AFLPs), and SNPs, which could lead to marker-assisted selection for breeding P. capsici-resistant lines [55,56]. Wang and associates [57] also developed SSR markers that tightly linked to the resistance gene in pepper line 'PI201234' . However, the previously developed markers from the different genetic maps could be insufficient to determine whether the QTL region includes a QTL that is conserved among different progenies.…”

“…However, the previously developed markers from the different genetic maps could be insufficient to determine whether the QTL region includes a QTL that is conserved among different progenies. P. capsici isolates with different virulence factors and/or inoculation concentrations also have variable disease phenotypes, which cause variation in cosegregation rates of molecular markers [43,57]. Rehrig and associates [44] reported cosegregated CaDMR1 with QTL Pc5.1 as a candidate for resistance to P. capsici in pepper, but its function was not determined yet.…”