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The selection of superior strawberry genotypes is a complex process due to the high variability after hybridization that is caused by the octoploid nature and the heterozygosis, making the selection of multiple traits difficult. This study aimed to select strawberry hybrids with the potential for fresh consumption and/or processing by applying multivariate analysis to obtain traits of interest simultaneously. Hybrids were obtained from the crossing among seven commercial cultivars, defining a selection of 10% of them. The experimental design consisted of an augmented block design, with two commercial cultivars, Camarosa and Camino Real, as the controls. Different variables, including the number and average mass of commercial fruits, total fruit mass, pH, soluble solids (SS), titratable acidity (TA), SS/TA ratio, reducing sugars, pectin, ascorbic acid, phenolic compounds, and anthocyanin’s, were assessed. The selection of hybrids was based on the Mulamba and Mock rank-summation index, principal component analysis, and Ward’s hierarchical cluster analysis. The selection index was based on different weights being adopted for fresh market and processing. The assessed traits had high variability between hybrids. The highest selection gains were obtained for production traits, but the different weight assignment resulted in different classifications of hybrids for both fresh consumption and processing. Most of the hybrids selected by the index remained in the same group in the principal component and hierarchical cluster analyses, which indicates that multivariate analysis is a valuable tool for assisting in the selection of superior hybrids in the strawberry crop.

Anthracnose, caused by Colletotrichum spp., is one of the most common diseases affecting sweet pepper and chilli pepper production worldwide, especially in tropical and subtropical zones. This disease results in severe fruit damage both pre‐ and postharvest. The development of resistant cultivars is the most effective strategy for disease control, which requires knowing the genetic basis of resistance. In this study, we analysed the inheritance of resistance of Capsicum annuum to Colletotrichum scovillei at two fruit development stages. The ripe and unripe fruits were inoculated by conidia suspension, and anthracnose severity was evaluated for 8 days using a score scale. It was found that the inheritance of resistance has independent expression in ripe and unripe fruits. In both cases, two main genes are responsible for resistance with polygenic effects. Genetic control, with a quantitative aspect, is more affected by dominance than the additive effects, in both fruit development stages of C. annuum.

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This study was performed to evaluate the effect of exogenous application of salicylic acid as a resistance inducer to two-spotted spider mite and tomato pinworm on tomato genotypes. Bioassays were carried out in three commercial genotypes (‘Redenção’, ‘Giuliana’, and ‘Alambra’) and one wild genotype (Solanum habrochaites var. hirsutum, accession PI-127826). Average distance travelled by the two-spotted spider mite and number of eggs deposited over the leaflets of the genotypes were investigated. Concerning pinworm bioassay, number of eggs, leafminers on leaflet surface and percentage of leaf area consumed by leafminers were evaluated using a scanner. Furthermore, severity of attack to plants was evaluated by score scale for damages, types of lesions and attacked leaflets. Salicylic acid application induced resistance in the commercial genotypes against both pests, reducing the two-spotted spider mite and pinworm oviposition. The spider mites travelled shorter distance on leaflets of genotypes treated with salicylic acid at intermediate concentrations, indicating a positive effect of substance as inducing resistance. Attack severity by pinworm was also reduced when intermediate doses of salicylic acid were applied. Also, higher resistance was observed on accession PI-127826 as compared to other genotypes. The obtained results indicate that the resistance of PI-127826 was due to constitutive defense, whereas on commercial genotypes defense was dependent on responses mediated by salicylic acid. Hence, salicylic acid treatment, as resistance inducer, seems to be efficient against two-spotted spider mite and pinworm, being a promising tool within an integrated pest management on tomato plants.