Resistance of pepper to bacterial leaf spot: A significant breeding task

Abstract

Bacterial spot of pepper (BS) caused by Xanthomonas euvesicatoria is one of the most important pepper diseases in Serbia. Growing of resistant pepper genotypes is the most efficient method for BS control. The study was initiated in 2013, when three sweet pepper lines from the Institute of Field and Vegetable Crops, Novi Sad, Serbia, were crossed with ECW-20R which is a donor of Bs2 gene. After crossing, three hybrids were sown in a greenhouse in October 2013 to obtain F2 generation. Those F2 transplants with ECW-20R, Cal. Wonder and line 30 were planted in 2014 in the open field and inoculated with X. euvesicatoria strain P8. Intensity of infection was evaluated according to the Horsfall-Barratt (HB) scale. Nonparametric Kruskal-Wallis test was used for statistical analysis. Plants from the F2 generation showed higher variability in resistance to bacterial leaf spot compared to parental lines. Based on the results obtained in F2 generation, plants from combinations B x ECW-20R and K x ECW-20R will be used in the further breeding activities. At this time ECW-20R (Bs2 gene) is a good donor for resistance to bacterial leaf spot under conditions prevailing in Serbia. Plants without symptoms will be used for further selection in order to develop resistant varieties to bacterial spot.

Bakteriozna pegavost paprike (prouzrokovač Xanthomonas euvesicatoria) je jedna od najznačajnijih bolesti paprike u Srbiji. Gajenje otpornih sorti paprike je najefikasniji način kontrole bakteriozne pegavosti. Istraživanje je počelo 2013. godine u Institutu za ratarstvo i povrtarstvo, Novi Sad, kada su tri linije slatke paprike ukrštene sa linijom ECW-20R koja nosi gen otpornosti na bakterioznu pegavost (Bs2). Nakon ukrštanja, seme tri dobijena hibrida je posejano u stakleniku u oktobru 2013. godine kako bi se dobila F2 generacija. Biljke F2 generacije su u 2014. godini u poljskim uslovima inokulisane bakterijom X. euvesicatoria. Intenzitet zaraze je ocenjen prema Horsfal-Barat (HB) skali. Neparametrijski Kruskal-Valis test je korišćen za statističku analizu. Biljke iz F2 generacije su pokazale znatno veću varijabilnost u otpornosti na bakterioznu pegavost u poređenju sa roditeljskim linijama. Biljke bez simptoma bakteriozne pegavosti će biti korišćene u daljem procesu selekcije radi dobijanja otpornih sorti.