Agronomic potential, pest resistance, and fruit quality in BC1F3 dwarf round tomato populations

Abstract

Combining broad pest resistance, high yield, and nutritional quality of fruit in the same hybrid is a challenge for round tomato breeders. Thus, development of a dwarf round tomato line for obtaining hybrids may be an excellent alternative for achieving such objectives. The aim of this study was to evaluate the agronomic potential, fruit quality, and pest resistance of BC1F3 dwarf round tomato populations. We evaluated 13 treatments and 4 replications. Treatments consisted of 10 BC1F3 dwarf populations originating from self-fertilization of dwarf populations selected in BC1F2, plus both parents (recurrent and donor) and a commercial hybrid. The traits evaluated were yield, number of fruit, mean weight, number of locules, shape, pulp thickness, longitudinal and transverse diameter of the fruit, precocity index, and soluble solids, β-carotene, lycopene, and acylsugar content. The data were analyzed through the means test. In general, there was an increase of up to 1035% in average fruit weight of the dwarf populations in relation to the donor parent. In addition, some dwarf populations had fruit with 49% more lycopene compared to the commercial hybrid, as well as greater acylsugar content in the leaves (273%). The UFU-DW22 dwarf population stood out with good agronomic potential, higher lycopene content in the fruit, and high acylsugar content, which provides pest resistance. To continue this research, a second backcross is suggested in order to obtain lines and, posteriorly, hybrids with round fruits and compact plants, pest resistance and nutritional quality of fruit.

Introgression of the Self-Pruning Gene into Dwarf Tomatoes to Obtain Salad-Type Determinate Growth Lines

“…Different types of acylsugars can be produced by tomato plants, especially in type IV glandular trichomes [ 44 ]. The production of these secondary metabolites can promote resistance against important tomato pests [ 39 , 45 ]. Due to the high concentrations of these metabolites in dwarf plants, breeding them to produce hybrids is a promising approach that also offers benefits like better fruit quality [ 37 , 39 , 41 ].…”

“…The identification of materials with high ACIL contents confers a greater spectrum of resistance against pests and is of great relevance in genetic improvement programs [ 39 , 41 ]. The use of dwarf plants to obtain hybrids with high ACIL contents could constitute a time-reducing strategy in breeding programs.…”

“…Another advantage provided by dwarf plants is their acylsugar content. This secondary metabolite is associated with greater pest resistance [ 39 , 41 ]. Both male parents stood out in terms of this trait, showing the potential for use in tomato breeding programs to generate resistant genotypes.…”

“…There are research reports that demonstrate the potential of using dwarf plants but with indeterminate growth habits [ 38 , 39 , 40 , 41 , 42 ] limiting obtaining determinate hybrids. However, to date, there are no studies on obtaining and selecting dwarf plants with a determinate growth habit of the Salad-type.…”