Genotypic and environmental effects on morphoagronomic performance in tomato hybrids derived from dwarf male parental lines

Abstract

The search for more productive and resilient tomato hybrids in the face of adverse growing conditions has intensified in the current climate scenario. The development of hybrids from dwarf tomato lines has become an efficient strategy to increase productivity through changes in plant architecture. Despite the advances achieved, the understanding of the use of dwarf lineages as male parents for obtaining Santa Cruz-type hybrids is still limited. Thus, the objective of this work is to obtain a germplasm bank of Santa Cruz-type dwarf tomato plants through successive backcrosses, and to develop compact, productive, and resilient hybrids from the crosses between normal lineages and dwarf lineages. The work was developed in two stages. The first stage consisted of characterizing dwarf tomato populations obtained after three backcrosses, aiming to observe the improvements achieved in each generation. In the second stage, Santa Cruz-type tomato hybrids derived from crosses between normal-sized lineages and dwarf lines were developed and evaluated under field and protected cultivation conditions regarding genotypic and environmental effects. Both experiments were conducted at the Vegetable Experimental Station of the Federal University of Uberlândia (UFU), Monte Carmelo, Minas Gerais, Brazil. In the first experiment, the dwarf tomato populations showed significant improvements in agronomic traits after three backcrosses. The dwarf plants showed high levels of acylsugars in the leaves and a significant increase in amino acids, especially L serine and glycine. In the second experiment, the Santa Cruz-type hybrids showed marked structural changes, such as reduction internode length and a greater number of bunches per linear meter, both in the field and under protected cultivation. In addition, the hybrids produced biofortified fruits and found high levels of acylsugars.