Backcrosses in a segregating population of Passiflora mediated by morphoagronomic and resistance traits

Abstract

The present study aims to characterize the genetic diversity of Passiflora setacea, P. edulis, their hybrids, and first-backcross progenies, and to indicate promising recombinants for generation advancement in a breeding program for transferring resistance to cowpea aphid-borne mosaic virus (CABMV). Ninety-one genotypes were evaluated for 37 morphoagronomic descriptors. The traits were analyzed to obtain a distance matrix, based on the Gower algorithm, using the Ward-Modified Location Model (MLM) procedure for the composition of genetic groups. The adopted strategy led to the formation of five homogeneous groups, where groups I, III, and V comprised the parents P. setacea, P. edulis and interspecific hybrids, respectively, while groups II and IV consisted of 69 genotypes of BC1. Broad variability was observed among the tested genotypes, and the hi ghest was shown by group IV. Genotypes 17, 293, 355, and 501, from group IV, were the most promising for the second backcross cycle as they showed good resistance to the disease and desirable morphoagronomic traits.