Produção e qualidade de tomate de mesa em telado fotosseletivo em diferentes manejos

• Autor(a) principal: Santos, Thayná Mendanha dos
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/8814
• topic: Solanum lycopersicum; Cultivo protegido; Radiação fotossinteticamente ativa; Telados fotosseletivos; Regulador de crescimento; Solanum lycopersicum; Protected cultivation; Photosynthetically active radiation; Photoselective nets; Plant growth regulators; AGRONOMIA::CIENCIA DO SOLO

Photoselective screens are a recent approach in protected cultivation, which can promote benefits in addition of the protective functions of nettings. These nets not only scatter but spectrally-modify the transmitted light, in order to promote desired physiological responses and improve the penetration of the light into the inner plant canopy. Tomato is the second most important horticulture crop in the world. Traditionally, tomato is cultivated in the open field, but recently there has been an increase of the protect cultivation area aiming to protect plants from climate adversities. This study aimed to investigate whether a combination of growth regulator, increased plant density and the effect of red screen-shade net could improve tomato yield, quality and promote desired vegetative development. The experiment was conducted from May 21st to November 1st, 2014, in Goiânia, Brazil (16º35´47´´S, 49°16´47´´W, 730 m). The hybrid Ivete from Sakata Seeds® were cultivated in 16x12x 2.2 m3, 40% red shading screenhouse and field plots as control. Leaf area index, trusses height, and total height were measured. The total number, total weight, diameter and number of lost fruits were totaled. Nutritional analyses were also performed: physical (Fresh mass, total solid soluble - TSS, titritable acidity - TA, SST/AT ratio and pH) and nutritional parameters (vitamin C and lycopene) in two moments of collecting of fruits (98 and 129 days after transplantation). All the measures were carried by official methods. Results showed that highest yields were obtained using 3 plants per m2 in both environments. The highest total fruit production occurred in open field conditions. However, the total fruit lost in the open field conditions was greater. Fruits produced in an open field were more acidic and had greater titratable acidity (0.37% citric acid) compared to fruits from screenhouse (0.33 % citric acid) at 3 plant per square meter. In addition, fruits grown in the field had greater TSS content (6.6 °Brix) than tomatoes grown in a protected environment (5.4 °Brix). Fruits produced in the open field had greater TSS:TA ratios than those produced in a protected environment. Significantly higher lycopene content was observed in plastic-house tomatoes integrated with red shade netting technologies (47.0 μg g−1) using 2.3 plants per m² than in open field-grown tomatoes (29.6 μg g−1). The results provide useful data for detecting differences among environment variation in tomato composition and red colour shade nets. In addition, the photoselective red screen combined with the density of 3 plants per m² promoted higher yield of commercial fruits.