MARKER ASSISTED BACKCROSS BREEDING FOR FUSARIUM WILT (Fusarium Oxysporum Schlecht. F. Sp. Melongenae) IN EGGPLANT

Abstract

Eggplants are produced in both greenhouses and open fields. Plant diseases and pests, and disease causes significant yield, thus economic losses loss. Fusarium wilt (Fusarium oxysporum Schlecht.f. sp. melongenae, FOM) is a major soil-borne pathogen, causing vascular wilt disease in eggplant. A molecular marker tightly linked to single dominant gene (FOM) was developed for use in marker assisted selection (MAS). The aim of the study is to develop eggplant lines resistant against Fusarium wilt using a marker assisted backcross breeding approach. Donor parents were carrying the Fusarium wilt resistance gene that six commercial hybrids claimed to have fusarium wilt resistance. The eggplant breeding materials (F1 to F8) was first screened with molecular markers linked to the FOM gene. Then, the 533 young seedlings were root-dip inoculated with FOM isolate. The seedlings identified to be resistant using the markers all survived in the inoculation. Although, the six hybrids that did not possess the marker locus for resistance against FOM were all resistant according to classical test. BC1F1, BC2F1 and BC3F1 population were developed from sensitive female and resistance male(commercial hybrids) crossing and all populations tested as classical and molecular. From resistance BC3F1 progenies 25 DH plants were obtained from each combination and resistance status of these plants was determined through initially molecular then classical testings. Results indicate that the marker was reliable to develop eggplant lines resistant against fusarium wilt, and there may can be another source of resistance that is independent from the known resistance gene originating from LS2436.