Productivity, acylsugar concentrations and resistance to the two-spotted spider mite in genotypes of salad tomatoes

Abstract

The objective of this study was to characterize genotypes of the salad-type tomato with a determinate growth habit and select genotypes resistant to the two-spotted spider mite for higher productivity and fruit quality. The experiment was conducted at the Horticultural Experimental Station (18°42’43.19” S and 47°29’55.8” W, 873 m altitude) of the Universidade Federal de Uberlândia (UFU), Monte Carmelo campus, from January to June 2018. The experimental design was in randomized blocks containing 16 treatments [12 populations of the F3RC2 generation and four controls: two commercial cultivars (Santa Clara and Rio Grande), the recurrent parent (UFU-057) and the wild species Solanum pennellii (LA-716)] with three repetitions. The accessions UFU-057F3RC210#3.6.1 and UFU-057F3RC213#2.1.2 have high potential for genetic improvement regarding resistance to the two-spotted spider mite. The genotypes UFU-13#4.4.1, UFU-7#4.7.1, UFU-7#4.3.2, UFU-13#2.5.2 and UFU-13#2.1.3 present higher acylsugar concentrations than S. pennellii, in addition to higher productivity and number of fruits per plant. It is suggested to explore combinations between those genotypes previously described with UFU-8#2.4.1 to obtain hybrids with high acylsugar concentrations, two-spotted spider mite resistance, high productivity and increased fruit mass.

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

“…In the present study, achieving higher lycopene and soluble solids content was made possible by the genetic variation of the genotypes, without requiring more complex biotechnological techniques that involve gene manipulation. Lucini et al, 2015;Rakha et al, 2017;Maciel et al, 2018a;Peixoto et al, 2019;Peixoto et al, 2020). In this study, the wild tomato S.pennellii had high contents of the acylsugar allelochemical (mean of 36.66 nmol cm -2 of leaf area), as was expected (Figure 3).…”

“…This can be achieved through introgression of genes belonging to wild species rich in allelochemicals, such as acylsugars. Acylsugar is mainly found in the glandular trichomes and promotes resistance to various pests by the mechanism of antixenosis (Maciel et al, 2018a, b;Peixoto et al, 2020). Combining broad resistance to pests and diseases, greater nutritional quality, and high yield in the same genetic material is the main challenge of breeders.…”

Artificial neural networks and genetic dissimilarity among saladette type dwarf tomato plant populations

“…Several studies have sought to increase genetic variability and gene introgression by using interspecific crosses of wild species ( Peixoto et al, 2020 , Zanin et al, 2021 ). However, the biggest challenge has been in recovering the agronomic potential and nutritional quality of the fruits after each crossing with wild species ( Peixoto et al, 2020 , Dariva et al, 2021 ).…”

“…Through this method, genetic dissimilarity was found between the BC 1 F 3 populations, parents, and the commercial cultivar by the formation of five groups. This methodology is traditionally used to represent genetic dissimilarity among tomato plant populations in various segments ( Maciel et al, 2018 , Finzi et al, 2020 , Peixoto et al, 2020 ).…”

“…Characterizing and analyzing the genetic dissimilarity of populations are essential for distinguishing divergent and promising genotypes ( Maciel et al, 2018 ). Traditionally, multivariate techniques have been used, such as dendrograms, the Tocher grouping method, canonical variables, and principal components to characterize the germplasms of normal tomato plants ( Maciel et al, 2018 , Alsamir et al, 2019 , Peixoto et al, 2020 ) and dwarf tomato varieties ( Finzi et al, 2020 ).…”