In sustainable cropping systems, the management of herbivorous arthropods is a challenge for the high performance of the tomato crop. One way to reduce the damage caused by these pests is the use of resistant cultivars within a sustainable integrated management system. The host selection of Tetranychus urticae, Bemisia tabaci, and Tuta absoluta was evaluated, characterizing their preference among the tomato genotypes RVTZ2011-79-503-143, RVTZ2011-79-335-164, RVTZ2011-79-185-250 (high zingiberene content—HZC), and RVTZ2011-79-117-273 (low zingiberene content—LZC). Such genotypes were selected in the F2BC2 generation (the F2 generation of the 2th backcross towards Solanum lycopersicum after the inicial interspecific cross S. lycopersicum × S. habrochaites var. hirsutum), resulting from crossing Solanum habrochaites var. hirsutum PI-127826 (HZC and resistant to mites) and the commercial cv. Redenção (S. lycopersicum) (LZC and susceptible to mites). In choice and no-choice bioassays by T. urticae, and in choice bioassays by B. tabaci and T. absoluta, arthropods preferred to stay and oviposit in an LZC genotype. In contrast, genotypes with HZC showed repellency to pests and induced a non-preference for oviposition. The F2BC2 genotypes selected for HZC are considered sources of resistance genes to these pests for tomato breeding programs, and therefore have excellent potential for sustainable cropping systems. These results represent an advance in obtaining tomato genetic materials which can be used in sustainable production systems with less loss from pests.

The marketable value of potato tubers is affected by damage caused by Diabrotica speciosa, whose larvae create holes on the tubers’ skin and internal feeding tunnels. The estimation of potato tuber damage is usually performed by assessing the external damage to the detriment of feeding tunnels caused by larvae. Thus, we propose a method to estimate the damage caused by D. speciosa larvae, considering the external and internal aspects of the tubers separately. For that, potato plants cv. Agata were grown under different infestations of larvae, measuring the area occupied by the holes and the volume of internal feeding tunnels, relating these data to the total area and volume of the tuber. The methodology used allowed us to characterize an increase in damage in tubers with the highest infestation of larvae. The correlation between internal and external damage caused by D. speciosa larvae was not significant, indicating that external damage alone is not an adequate parameter for the diagnosis of overall tuber quality. However, the method proposed here provides information regarding the volume of pulp consumed by the larvae, the extent of the galleries formed, and the relative volume of damage concerning the total tuber. Moreover, the method proposed here contemplates a more precise analysis of the external area damaged by herbivory relative to the total area of the tuber, which is not commonly considered in studies of underground plant structures.

This study reports for the first time the plant bug Microtechnites bractatus (Say) in Crotalaria juncea and Crotalaria spectabilis, in the state of Paraná, Brazil. We characterized the injuries caused by M. bractatus and Collaria scenica Stal in cultivated plants and in Crotalaria spp. Considering that M. bractatus damage has been incorrectly attributed to C. scenica, we present here a contribution to the correct characterization of these insect pests and their damage over some agricultural crops.

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Tomato plants are highly susceptible to pests. Among the control methods, genetic improvement with introgression of resistance genes from wild accessions into commercial tomato lines is the best alternative for an integrated pest management (IPM). Thus, the objective of this study was to select tomato genotypes in advanced populations (F2BC3), with higher levels of acylsugar content, greater recurrent parent genome recovery, and resistance to Tetranychus urticae and Bemisia tabaci inherited from Solanum pennellii. For pest resistance, bioassays were assessed: nine high-acylsugar genotypes, four low-acylsugar genotypes, and the parents, Solanum lycopersicum or ‘Redenção’, and Solanum pennellii LA-716. Glandular and non-glandular trichomes were quantified. A negative correlation was measured between acylsugar content in the leaflets and pest behavior. Pest resistance was found in the selected F2BC3 genotypes with high-acylsugar content, indicating that this allelochemical was efficient in controlling the arthropod pests.

In this study we evaluated the performance of potato cultivars in the organic production system, aiming to identify those more productive and less damaged by Phytophthora infestans and Diabrotica speciosa. The experiment was conducted during the 2013/2014 and 2014/2015 crop seasons. Cultivars Ágata, Aracy Ruiva, Vitória, Clara, Eliza, Catucha and Cris were assessed for severity and area under disease progress curve (AUDPC) of P. infestans, external holes and internal galleries caused by D. speciosa, and tuber yield. Most cultivars reacted positively to P. infestans and D. speciosa. ‘Ágata’ was the most susceptible cultivar, with P. infestans severity close to 100% and AUDPC significantly higher than the other cultivars. D. speciosa larvae external damages were more intense in ‘Eliza’ than in ‘Clara’ and ‘Catucha’. ‘Eliza’ was also among the most internally damaged cultivars in both years, while ‘Catucha’ and ‘Vitória’ were among the least internally damaged. The results indicate ‘Catucha’ and ‘Clara’ as the most suitable for organic cultivation among the studied materials.