Tecido-não-tecido (TNT) para ensacamento de cachos visando controle de broqueadores de frutos do tomateiro (Solanum lycopersicum L.)

Abstract

The tomato plants are attacked by pest insects throughout its cycle, among which the arthropods fruit borers stand out. The objective of this experiment was to evaluate the efficiency of nonwoven („TNT‟) using in bagging flowers and/or fruits of 'Valerin' tomato as a mechanical control to fruit borers and evaluating thus the agronomic indicators of crop, post-harvest fruit quality, cost/benefit as well as the best period to perform bagging. The experiment was conducted in a commercial planting of staked tomato plants, located in the municipality of Ubajara, Ceará, Brazil, in randomized blocks in factorial 2 x 4 with five repetitions. The following factors were considered: two ways of using insecticides to control borers [1-plants treated with insecticides; 2-Plants not treated with insecticides] and the four periods of bagging the bunches with nonwoven [T1-Flower bagging; T2-Bagging the bunches with fruits of 1.5 cm in diameter; T3 Bagging the bunches with fruits of 3.0 cm in diameter); and Bunches not bagged (control)]. The parameters evaluated were: number of fruits/bunch, number of bunches/plant, fruit weight (Kg), longitudinal diameter (cm), transverse diameter (cm), incidence of borers insects (%), productivity (Kg/ha), loss caused by the attack of pests (Kg/ha), real gain obtained (Kg/ha), cost benefit of implementation, titratable acidity, total soluble solids, fuit color (brightness, chromaticity, hue angle), fruit firmness, total carotenoids, lycopene and ß-carotene. Postharvest analysis were performed in the Laboratory of Postharvest of Embrapa Agroindústria Tropical. The use of nonwoven in the bagging of 'Valerin' clusters/tomato fruits did not affected the productive performance neither the quality postharvest of the ruits. The average cost for bagging the fruits with nonwoven ags was about 40.7% lower than that required for chemical control. It was not observed the presence of Tuta absoluta (Lepidoptera: Gelechiidae), Helicoverpa zea and Helicoverpa armigera (Lepidoptera: Noctuidae) during evaluations, however the bagging of 'Valerin' tomato clusters with nonwoven when the fruits was 1.5 cm in diameter was effective to control Neoleucinodes elegantalis (Lepidoptera: Crambidae), promoted increase of 21.5% in the final productivity if compared to those not bagged and did not compromise the post-harvest quality of the fruits and thus it is considered the best period to perform bagging.