====== Pepper (//Capsicum annuum//) ======
Author: [[https://www.researchgate.net/profile/Dorota_Tekielska|Dorota Tekielska]]\\
Internal reviewer: [[https://www.genetik.uni-hannover.de/boch.html|Jens Boch]]\\
Expert reviewer: FIXME
===== Pathogen: //Xanthomonas euvesicatoria// =====
==== Resistance gene: //Bs1// ====
=== Synonyms ===
//NA//
=== Source ===
//Capsicum annuum// PI163192 (Cook & Guevara, 1984).
=== Status (identified, mapped, cloned, sequenced) ===
Identified. //Bs1// was backcrossed over 7 generations into the commercial pepper cultivar Early Calwonder (ECW) to produce a near-isogenic pepper cultigen (ECW10R) for identification of race 1 and race 2 pathogenic strains (Stall //et al//., 2009). The three resistance genes //Bs1//, //Bs2//, and //Bs3// were transferred to a single plant of ECW and designated ECW123.
=== Molecular markers ===
//NA//
=== Brief description ===
//Bs1// is a dominant resistance which results in a fast hypersensitive response reaction upon recognition of the type III effector AvrBs1 from //Xanthomonas euvesicatoria //pv. //euvesicatoria// (aka //Xanthomonas campestris //pv. //vesicatoria//). The resistance is rapidly overcome in the field by mutation of //avrBs1// in the bacteria making this resistance unsuitable for commercial breeding.
----
==== Resistance gene: //Bs2// ====
=== Synonyms ===
//NA//
=== Source ===
//Capsicum chacoense// (Cook & Stall, 1963).
=== Status (identified, mapped, cloned, sequenced) ===
//Bs2// was the first cloned resistance gene in pepper (Tai //et al.//, 1999). //Bs2// was backcrossed over 7 generations into the commercial pepper cultivar Early Calwonder (ECW) to produce a near-isogenic pepper cultigen (ECW20R) (Stall //et al//., 2009). The three resistance genes //Bs1//, //Bs2//, and //Bs3// were transferred to a single plant of ECW and designated ECW123.
=== Molecular markers ===
Markers for breeding of //Bs2// in pepper have been established (Truong //et al//., 2011). An overview of markers for different disease resistances in pepper has been published (Barka & Lee, 2020).
=== Brief description ===
The dominant //Bs2// resistance gene encodes an NB-LRR protein which interacts with the AvrBs2 protein from //Xanthomonas euvesicatoria //pv. //euvesicatoria// (aka //Xanthomonas campestris //pv. //vesicatoria//)and causes a hypersensitive response (Tai //et al//., 1999). Expression of //Bs2// in other solanaceous plants, but not nonsolanaceous plants, also triggers hypersensitive response to AvrBs2. //Bs2// was broadly used in resistance breeding and in 2000 nearly 100% commercial bell peppers contained the //Bs2// resistance. Because pathogen strains with mutations in //avrBs2// emerged, //Bs2// was only effective for commercial control of bacterial spot disease for 5-6 years.
----
==== Resistance gene: //Bs3// ====
=== Synonyms ===
//NA//
=== Source ===
//Capsicum annuum// PI271322 (Kim & Hartmann, 1985).
=== Status (identified, mapped, cloned, sequenced) ===
Cloned and sequenced (Roemer //et al//., 2007). A near-isogenic line containing the //Bs3// (ECW30R) (Stall //et al//., 2009). The three resistance genes //Bs1//, //Bs2//, and //Bs3// were transferred to a single plant of ECW and designated ECW123.
=== Molecular markers ===
//NA//
=== Brief description ===
//Bs3// is a dominant resistance gene and not expressed during normal life of the plant. The TAL effector AvrBs3 from //Xanthomonas euvesicatoria //pv. //euvesicatoria// (aka //Xanthomonas campestris //pv. //vesicatoria//) binds to the promoter of //Bs3// and causes expression which results in programmed cell death (Römer //et al//., 2007). //Bs3// encodes an unusual flavin monooxygenase, but it is unknown whether the Bs3 protein has any enzymatic activity. The //bs3// variant has a deletion in the promoter which prohibits binding of AvrBs3 (Römer //et al//., 2007). Instead, //bs3// is triggered by binding of a variant of AvrBs3 with deletions of several repeats that cause it to recognize the modified sequence in the promoter of //bs3 // (Römer //et al//., 2007). The TALE AvrHah1 from //Xanthomonas gardneri// also elicits the //Bs3// resistance. Commercial pepper lines containing //Bs2// and //Bs3// were used.
----
==== Resistance gene: //Bs4// ====
=== Synonyms ===
//NA//
=== Source ===
//Capsicum pubescens// PI235047 (Stall //et al//., 2009).
=== Status (identified, mapped, cloned, sequenced) ===
Identified in pepper, cloned from tomato (Schornack //et al//., 2004).
=== Molecular markers ===
//NA//
=== Brief description ===
//Bs4// is a dominant resistance gene. It has not been introgressed into pepper, because //C. annuum// can not be crossed with //C. pubescens.//
----
==== Resistance gene: //bs5// ====
=== Synonyms ===
//NA//
=== Source ===
//Capsicum annuum// ECW12346 (Jones //et al//., 2002; Vallejos //et al//., 2010).
=== Status (identified, mapped, cloned, sequenced) ===
Identified, mapped. //bs5// has been transferred to the pepper cultivar ECW, backcrossed, and designated ECW50R.
=== Molecular markers ===
AFLP markers are available (Vallejos //et al//., 2010).
=== Brief description ===
//bs5// is a recessive resistance which has been mapped. It is a stronger resistance than the other recessive resistance, //bs6//, but both resistances together have an additive effect (Vallejos //et al//., 2010).
----
==== Resistance gene: //bs6// ====
=== Synonyms ===
//NA//
=== Source ===
//Capsicum annuum// ECW12346 (Jones //et al//., 2002; Vallejos //et al//., 2010).
=== Status (identified, mapped, cloned, sequenced) ===
Identified. //bs6// has been transferred to the pepper cultivar ECW, backcrossed, and designated ECW60R.
=== Molecular markers ===
not available
=== Brief description ===
//bs6// is a recessive resistance which has not been mapped, so far. It is a weaker resistance than the other recessive resistance, //bs5//, but both resistances together have an additive effect (Vallejos //et al//., 2010).
----
==== Resistance gene: //BsT// ====
=== Synonyms ===
//NA//
=== Source ===
//Capsicum pubescens// PI235047A.
=== Status (identified, mapped, cloned, sequenced) ===
Identified.
=== Molecular markers ===
N/A
=== Brief description ===
The dominant //BsT// resistance gene from //C. pubescens// causes a hypersensitive response upon recognition of the type III effector AvrBsT from //Xanthomonas euvesicatoria //pv. //euvesicatoria// (aka //Xanthomonas campestris //pv. //vesicatoria//)//.// Expression of //avrBsT// in //C. annuum// using //Agrobacterium// causes an HR and infection of papper with //Xcv// strains containing //avrBsT// on a high-copy plasmid causes a spotty hypersensitive reaction (Escolar //et al//., 2001) indicating that //BsT// is also present in //C. annuum//.
----
===== Pathogen: //Xanthomonas hortorum// pv. //gardneri// =====
==== Resistance gene: //Bs7// ====
=== Synonyms ===
//NA//
=== Source ===
//Capsicum baccatum// var. //pendulum// (Potnis //et al//., 2012).
=== Status (identified, mapped, cloned, sequenced) ===
Identified.
=== Molecular markers ===
//NA//
=== Brief description ===
//Bs7// is a dominant resistance gene.
----
==== Resistance gene: //bs8// ====
=== Synonyms ===
//NA//
=== Source ===
//Capsicum annuum// accession PI 163192 (Sharma //et al//., 2022).
=== Status (identified, mapped, cloned, sequenced) ===
Mapped to a 2.3 Mb interval on the sub-telomeric region of chromosome 11 (Sharma //et al//., 2022). //bs8// has been transferred to the pepper cultivar ECW, backcrossed, and designated ECW80R.
=== Molecular markers ===
Markers from mapping population (Sharma //et al//., 2022)
=== Brief description ===
//bs8// is a recessive resistance which has been mapped. This resistance in ECW80R was determined to be quantitative, recessively inherited, and non-HR causing, and inhibits lesion expansion and chlorosis. Presence of the resistance in NILs decreased the //in planta// bacterial population by 9-fold compared to ECW (Sharma //et al//., 2022).
----
===== References =====
Barka GD, Lee J (2020). Molecular marker development and gene cloning for diverse disease resistance in pepper (//Capsicum annuum// L.): current status and prospects. Plant Breed. Biotech. 8: 89-113. DOI: [[https://doi.org/10.9787/PBB.2020.8.2.89|10.9787/PBB.2020.8.2.89]]
Cook AA, Stall RE (1963). Inheritance of resistance in pepper to bacterial spot. Phytopathology 53: 1060-1062.
Escolar L, van den Ackerveken G, Pieplow S, Rossier O, Bonas U (2001). Type III secretion and in planta recognition of the //Xanthomonas// avirulence proteins AvrBs1 and AvrBsT. Mol. Plant Pathol. 2: 287-296. DOI: [[https://doi.org/10.1046/j.1464-6722.2001.00077.x|10.1046/j.1464-6722.2001.00077.x]]
Jones JB, Minsavage GV, Roberts PD, Johnson RR, Kousik CS, Subramanian S, Stall RE (2002). A non-hypersensitive resistance in pepper to the bacterial spot pathogen is associated with two recessive genes. Phytopathology 92: 273-277. DOI: [[https://doi.org/10.1094/PHYTO.2002.92.3.273|10.1094/PHYTO.2002.92.3.273]]
Kim BS, Hartmann RW (1985). Inheritance of a gene (//Bs3//) conferring hypersensitive resistance to //Xanthomonas campestris// pv. //vesicatoria// in pepper (//Capsicum annuum//). Plant Dis. 69: 233-235.
Potnis N, Minsavage G, Smith JK, Hurlbert JC, Norman D, Rodrigues R, Stall RE, Jones JB (2012). Avirulence proteins AvrBs7 from //Xanthomonas gardneri// and AvrBs1. 1 from //Xanthomonas euvesicatoria// contribute to a novel gene-for-gene interaction in pepper. Mol. Plant Microbe Interact. 25: 307-320. DOI: [[https://doi.org/10.1094/MPMI-08-11-0205|10.1094/MPMI-08-11-0205]]
Römer P, Hahn S, Jordan T, Strauss T, Bonas U, Lahaye T (2007). Plant pathogen recognition mediated by promoter activation of the pepper //Bs3// resistance gene. Science 318: 645-648. DOI: [[https://doi.org/10.1126/science.1144958|10.1126/science.1144958]]
Sharma A, Minsavage GV, Gill U, Hutton S, Jones JB (2022). Identification and mapping of //bs8//, a novel locus conferring resistance to bacterial spot caused by //Xanthomonas gardneri//. Phytopathology, in press. DOI: [[https://doi.org/10.1094/PHYTO-08-21-0339-R|10.1094/PHYTO-08-21-0339-R]]
Stall RE, Jones JB, Minsavage GV (2009). Durability of resistance in tomato and pepper to xanthomonads causing bacterial spot. Ann. Rev. Phytopathol. 47: 265-284. DOI: [[https://doi.org/10.1146/annurev-phyto-080508-081752|10.1146/annurev-phyto-080508-081752]]
Tai TH, Dahlbeck D, Clark ET, Gajiwala P, Pasion R, Whalen MC, Stall RE, Staskawicz BJ (1999). Expression of the //Bs2// pepper gene confers resistance to bacterial spot disease in tomato. Proc. Natl. Acad. Sci. USA 96: 14153-14158. DOI: [[https://doi.org/10.1073/pnas.96.24.14153|10.1073/pnas.96.24.14153]]
Truong HTH, Kim KT, Kim S, Cho MC, Kim HR, Woo JG (2011). Development of gene-based markers for the //Bs2// bacterial spot resistance gene for marker-assisted selection in pepper (//Capsicum// spp.). Hort. Environ. Biotechnol. 52: 65-73. DOI: [[https://doi.org/10.1007/s13580-011-0142-4|10.1007/s13580-011-0142-4]]
Vallejos CE, Jones V, Stall RE, Jones JB, Minsavage GV, Schultz DC, Rodrigues R, Olsen LE, Mazourek M (2010). Characterization of two recessive genes controlling resistance to all races of bacterial spot in peppers. Theor. Appl. Genet. 121: 37-46. DOI: [[https://doi.org/10.1007/s00122-010-1289-6|10.1007/s00122-010-1289-6]]
----
===== Further reading =====
Choi HW, Hwang BK (2015). Molecular and cellular control of cell death and defense signaling in pepper. Planta 241: 1-27. DOI: [[https://doi.org/10.1007/s00425-014-2171-6|10.1007/s00425-014-2171-6]]
Hibberd AM, Gillespie D (1982). Heritability of field resistance to bacterial leaf spot disease in pepper (//Capsicum annuum// L.). Scientia Hortic. 17: 301-309. DOI: [[https://10.1016/0304-4238(82)90110-8|https://doi.org/10.1016/0304-4238(82)90110-8]]
Hong JK, Hwang IS, Hwang BK (2017). Functional roles of the pepper leucine-rich repeat protein and its interactions with pathogenesis-related and hypersensitive-induced proteins in plant cell death and immunity. Planta 246: 351-364. DOI: [[https://doi.org/10.1007/s00425-017-2709-5|10.1007/s00425-017-2709-5]]
Leister RT, Dahlbeck D, Day B, Li Y, Chesnokova O, Staskawicz BJ (2005). Molecular genetic evidence for the role of SGT1 in the intramolecular complementation of Bs2 protein activity in //Nicotiana benthamiana//. Plant Cell 17: 1268-1278. DOI: [[https://doi.org/10.1105/tpc.104.029637|10.1105/tpc.104.029637]]
Park CJ, Shin R, Park JM, Lee GJ, You JS, Paek KH (2002). Induction of pepper cDNA encoding a lipid transfer protein during the resistance response to tobacco mosaic virus. Plant Mol. Biol. 48: 243-254. DOI: [[https://doi.org/10.1023/a:1013383329361|10.1023/a:1013383329361]]
Riva EM, Rodrigues R, Pereira MG, Sudré CP, Karasawa M (2004). Inheritance of bacterial spot disease in //Capsicum annuum// L. Crop Breed. Appl. Biotechnol. 4: 490-494. DOI: [[https://doi.org/10.12702/1984-7033.v04n04a18|10.12702/1984-7033.v04n04a18]]
Riva-Souza EM, Rodrigues R, Sudré CP, Pereira MG, Bento CS, de Pina Matta F (2009). Genetic parameters and selection for resistance to bacterial spot in recombinant F6 lines of //Capsicum annuum//. Crop Breed. Appl. Biotechnol. 9: 108-115. PDF: [[http://www.sbmp.org.br/cbab/siscbab/uploads/c8129491-83fe-7669.pdf|www.sbmp.org.br/cbab/siscbab/uploads/c8129491-83fe-7669.pdf]]
Riva-Souza EM, Rodrigues R, Sudré CP, Pereira MG, Viana AP, do Amaral jr. AT (2007). Obtaining pepper F2:3 lines with resistance to the bacterial spot using the pedigree method. Horticultura Brasileira 25: 567-571. PDF: [[https://www.scielo.br/pdf/hb/v25n4/a14v25n4.pdf|www.scielo.br/pdf/hb/v25n4/a14v25n4.pdf]]
Romero AM, Kousik CS, Ritchie DF (2002). Temperature sensitivity of the hypersensitive response of bell pepper to //Xanthomonas axonopodis// pv. //vesicatoria//. Phytopathology 92: 197-203. DOI: [[https://doi.org/10.1094/PHYTO.2002.92.2.197|10.1094/PHYTO.2002.92.2.197]]
Silva LRA, Rodrigues R, Pimenta S, Correa JWS, Araújo MSB, Bento CS, Sudré CP (2017). Inheritance of bacterial spot resistance in //Capsicum annuum// var. //annuum//. Genet. Mol. Res. 16: gmr16029631. DOI: [[https://doi.org/10.4238/gmr16029631|10.4238/gmr16029631]]
Stall RE, Jones JB, Minsavage GV (2009). Durability of resistance in tomato and pepper to xanthomonads causing bacterial spot. Ann. Rev. Phytopathol. 47: 265-284. DOI: [[https://doi.org/10.1146/annurev-phyto-080508-081752|10.1146/annurev-phyto-080508-081752]]