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Vast numbers of studies on tomato breeding have been performed for resistance to environmental stresses and pests. In genetic investigation and breeding of tomato, it is tried to use tomato lines with the most variance on morphological and agronomical traits to obtain better results, like maximum heterosis on F1 hybrids. In this survey combining ability and heterosis of 7 inbred lines (ME, KaLN3, Fla, CT6, LA3770, R2-05, and DB) of tomato and their F1 hybrids were investigated for salinity tolerance during the seedling stage using the diallel-cross. Therefore, seed germination percentage, seedling emergence percent and rate under salt-stress, tested in a complete randomized design with four replications. Results show that the reciprocal effects and SCA were significant for all traits on the probability of 1 %. Analysis of Wr-Vr regression also shown that seed germination percentage and seedling emergence percentage and rate under salt stress controlled by over-dominance effects. The best line for resistance to salt stress in juvenility was R205, which has the most GCA for all three traits connected to salt resistance. It may be beneficial to combine this line as a parental line in breeding programs for increasing salinity tolerance of tomato during the seedling stage.

Although the Torbiscal line of Iberian pigs has been largely studied, some aspects of its history are not well known. In this paper, we used pedigree-based methods on a complete genealogy of 4,077 entries in order to get a comprehensive analysis of its four founder strains and to evaluate the expected genetic contribution of each ancestral strain to the successive generations of the composite Torbiscal line. Between-strain differences and specific heterotic effects on piglet weight at 50 days of age were estimated from records of 9,052 piglets born in 1,571 litters of a complete diallel cross among the four strains. Moreover, we assessed the genetic singularity of the current Torbiscal pigs by other three studies, based on whole genome SNP genotypes, focused on the measure of its genetic diversity and differentiation with respect to other domestic and wild pig populations. The STRUCTURE algorithm detected two uppermost levels of the whole population structure, corresponding to European and Asian ancestries. These results confirmed the exclusive European origin of the Torbiscal and other Iberian pigs and the admixed origin of the Duroc breed. Finally, the comparison of Torbiscal with a representative pool of Iberian pigs showed a maximum genetic differentiation in regions of chromosomes three and seven, including some genes related to the regulation of muscle development.