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One of the major problems in cultivation of tomato is the occurrence of pests and diseases. The objective of the research was to select genotypes from the second generation of the first backcross (F2BC1) between the tomato cultivar for processing S. lycopersicum (cv. Redenção) and the wild access S. habrochaites var. hirsutum (PI-127826), with high levels of zingiberene (ZGB), resistant to the twospotted spider mite Tetranychus urticae (Acari: Tetranychidae). From the F2BC1 population. The ZGB content was quantified and five plants with high zingiberene selected (RVTZ 2011-079-117, RVTZ 2011-079-185, RVTZ 2011-079-335, RVTZ 2011-079-345 and RVTZ 2011-079-503) and four with low zingiberene content (RVTZ 2011-079-417, RVTZ 2011-331-460, RVTZ 2011-079-538 and RVTZ 2011-079-548) were selected. Genotypes selected for high and low ZGB content and the parentals S. habrochaites var. hirsutum access PI-127826 and ‘Redenção’ were evaluated for repellency to the twospotted spider mite. There was a significant and inverse correlation between ZGB content and average distances travelled by mites on tomato leaflets. The genotypes of the F2BC1 generation with high zingiberene levels RVTZ 2011-079-117, RVTZ 2011-079-185, RVTZ 2011-079-335, RVTZ 2011-079-345 and RVTZ 2011-079-503 are promising for progress in achieving resistant lines to arthropod pests. Among them RVTZ 2011-079-117 stands out for resistance to twospotted spider mite.

Strawberry is a crop of great economic and social importance. Its fruits are appreciated both for their flavor and nutraceutical potential. Some studies confirm that light quality influences plant physiology. Thus, the aim of this study was to investigate if changes in light spectrum, provided by low tunnels, can improve vegetative traits, as well as, production and fruit quality of strawberry. The authors used six tunnel covers (red, yellow, blue, green, transparent and opaque and one control, without cover), and two cultivars: a short photoperiod cultivar (Camarosa) and a neutral photoperiod cultivar (Albion). Experiment was evaluated in two seasons: production and plant development first; and then, post-harvest quality. Overall, Camarosa showed higher vegetative growth, lower production, and better fruit quality than Albion. Due to the complexity of physiological and biochemical responses, each trait evaluated showed a specific response to light changes. The red, blue, yellow and green covers did not show any significant improvement comparing with transparent and opaque covers. Thus, the authors suggest the use of the latter ones which have already been used commercially.

Several strawberry growers have cultivated the same plants for two consecutive cycles aiming a greater economic return after seedling transplant. However, the phenological development and the agronomic potential of second-cycle strawberry have to be estimated. This research was installed to estimate the thermal need, leaf appearance rate, phyllochron and yield of strawberry cultivars in two consecutive crop cycles in the region of the Third Planalto Paranaense. Cultivars Camarosa, Camino Real, Albion, Aromas, Monterrey and San Andreas were evaluated in the first and second growing cycles using completely randomized blocks and four replications. Leaf appearance rate was estimated by linear regression coefficient between the number of leaves and the accumulated thermal sum. Phyllochron was estimated by the inverse of regression coefficient. Aromas was the only cultivar with an increased fruit production in the second cycle. On the contrary, there was a considerable reduction of production for ‘Camino Real’, ‘Albion’, ‘Monterrey’ and ‘San Andreas’ in that same cycle. The highest number and mass of marketable fruits of the second and first cycles were observed for ‘Camarosa’ and ‘Camino Real’, respectively. In the second crop cycle, strawberry cultivars required a lower thermal sum to begin flowering and fruit harvest. The plants presented a higher leaf appearance rate and low phyllochron values.

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