New melon introgression lines in a Piel de Sapo genetic background with desirable agronomical traits from dudaim melons

Abstract

A new collection of introgression lines (ILs) have been developed using the Spanish cultivar ‘Piel de Sapo’ (PS, subsp. melo, group ibericus) as the recurrent parent, and ‘Queen’s pocket melon’ (DUD, subsp. melo, group dudaim PI 273438) as donor. Genome-wide markers assisted selection has been proceed in several backcross generations to obtain a set of 16 ILs. An average of 1.4 introgressions/plant representing altogether about 62% of the DUD genome, and with an average of recovery per IL of 93.9% of the PS genetic background, has been accomplished in the selected ILs after several backcrosses and selfings. QTLs for abscission layer, external aroma, rind and flesh firmness, rind netting, fruit weight and shape, and sugar content have been identified on this set of ILs some of them corresponding to genomic regions previously described or with interesting candidate genes, but, also, new allelic diversity has been identified. Thus, this set of ILs may be useful to exploit new underexploited genetic variability from DUD. Based on GBS results for five of this ILs, further steps of backcrossing will be necessary to clean up the small introgressions detected in some of them. Novel phenotypes like small PS melons or aromatic and medium-climacteric PS melons were obtained, which might become pre-breeding lines with potential commercial interest.