This study carried out agronomic evaluation and estimated the combining ability of tomato lines for the industrial segment, aiming to elect promising genotypes for breeding and to find simple hybrids with superior traits. Randomized-blocks design was used with 57 treatments (45 experimental hybrids, 10 lines and 2 checks treatments) with 3 replications. A complete diallel among 10 tomato lines for processing was used. Evaluated traits were: fruit total (YT) and commercial production (YC), pulp yield (YP), fruit average mass (MM) and total soluble solids content (TSS). Diallel crosses allowed synthesizing experimental hybrids with superior traits when compared to commercial hybrids. Non-additive effects prevailed over the expression of YT, YC, YP and TSS, whereas additive effects prevailed for MM. Lines RVT-08, RVT-05 and RVT-10 are most appropriate for intrapopulational breeding. Experimental hybrids RVT-08 x RVT-09, RVT-07 x RVT-10 and RVT-08 x RVT-10 were pointed as the experimental genotypes with the best performance, surpassing the commercial genotypes for the traits evaluated.

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In this study, we aimed to estimate general and specific combining abilities (GCA and SCA, respectively) and to verify genetic divergence (Rogers distance, Unweighted Pair-Group Method Using Arithmetic Average - UPGMA) using microsatellite markers in maize inbred lines. Using a partial diallel scheme, a total of 19 inbred lines were crossed as (9 x 10), which were derived from the single hybrids SG6015 and P30F53, respectively. The 90 hybrids were evaluated in an incomplete randomized block design with common checks and three replications during the 2017-2018 growing season. Flowering time, average plant height, ear height insertion, average ear diameter, ear length, number of lodged and broken plants, mass of 100 grains and grain yield were measured. According to the analysis of variance, GCA, and SCA were significant (p < 0.05) in all the measured traits; inbred line B as well as 1 and 8, derived from the single hybrids SG6015 and P30F53, respectively, were selected due to their higher GCA values in grain yield to be used in crosses as testers, while the single cross hybrid (B x 1) was selected due to their higher SCA value in grain yield to be used in future breeding programs. The molecular marker analysis divided the inbred lines into two groups, where the highest dissimilarity (0.74) was observed between lines A and 9; however, these did not result in a high SCA value, therefore the hybrids obtained by such crossings were not selected for grain yield.

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ResumoO objetivo do trabalho foi avaliar o comportamento relativo de 74 linhagens parcialmente endogâmicas (S 4 ) provenientes do cruzamento entre os híbridos comerciais P30P70 e Dow8460 em topcrosses com o híbrido simples comercial P30F53 (testador), mais as testemunhas (híbridos Dow8460, P30F53 e Status). A produtividade de grãos (PG) foi avaliada em dois ambientes em Guarapuava-PR. Houve efeito significativo de genótipos, ambientes e da interação genótipos x ambientes quanto à produtividade de grãos (PG AbstractThe objective of this study was to evaluate the relative performance of 74 partially inbred lines (S 4 ) from crosses between the commercial hybrids P30P70 and Dow8460 in topcrosses with the commercial single cross hybrid P30F53 (tester), and checks (hybrids Dow8460, P30F53 and Status). The grain yield (GY) was evaluated in two environments in Guarapuava-PR. The effects of genotypes, environments