Performance of the double-cross tomato hybrids from a partial diallel

Abstract

Knowledge of the combining ability of genotypes, genetic diversity, and heterosis play the paramount role in obtaining double-cross hybrids with high productivity. This study was aimed at evaluating these parameters in tomato genotypes using partial diallel crosses among the commercial single-cross hybrids, which verified the possibility of using double-cross hybrids for commercial purposes. Tomato genotypes included 15 double-cross hybrids, their genitors, and two commercial genotypes as checks. Of the fifteen double-cross hybrids of tomato, two crosses exhibited superiority, such as Aguamiel × Compack and Dominador × Compack, mainly for the total and commercial fruit yields. The phenotypic expression of the trait is controlled by the genes with non-additive effects, whereas the genes with additive effects account for the genotypes of fruit mass, horizontal diameter, vertical diameter, and bunch insertion height. Regarding the genetic diversity, molecular analyses pointed out polymorphism for 79 percent of the evaluated loci evidencing a high genetic variability among the genitors. The heterosis values were low for most of the crosses, except for Forty × Plutão that represented 107 percent of heterosis for the total fruit yield. As compared with the commercial checks, the diallel cross generated superior quality hybrids, which inferred the possibility of obtaining double-cross hybrids of tomato with significant heterosis.

Half diallel of F1 tomato hybrid and its double cross-compatibility

“…Double crosses can create greater population diversity than single cross F1 (Acquaah 2012;Muthoni and Shimelis 2020;Joshi and Gautam 2021). This concept is crucial in producing adaptive tomato varieties that suit consumer expectations (Campanelli et al 2019;Matos et al 2021). These double-cross from the half-diallel single cross can be combined with diallel mating, and this concept has been reported by Matos et al (2021).…”

“…This concept is crucial in producing adaptive tomato varieties that suit consumer expectations (Campanelli et al 2019;Matos et al 2021). These double-cross from the half-diallel single cross can be combined with diallel mating, and this concept has been reported by Matos et al (2021). Furthermore, the combination from half diallel can form F1 double and unbalanced three-way crosses.…”