Tomateiro cereja sob disponibilidades hídricas e doses de potássio com irrigação semiautomatizada em ambiente protegido

Abstract

IntroductionThe tomato crop (Lycopersicon esculentum Mill.) stands out among the most produced vegetables in Brazil, among its cultivars stands out as the cherry group. However, available water and soil fertility are among the main factors affecting productivity. Purpose: To evaluate the products characteristics, fruit quality and use of water of cherry tomato crop under water availability and potassium rates, cultivated in a pot with Oxisol in a protected environment. Material and Method:The experiment was conducted in a greenhouse with a randomized block design in a 5x5 factorial scheme, with five soil water availability (4, 14, 24, 34 and 44 kPa) and five potassium doses (0, 125, 250, 375 And 500 mg dm-3), in a fractional factorial arrangement 5² based on the central compound adapted by Littell & Mott (1975), resulting in 13 treatments (4 - 0; 4 - 250; 4 - 500; 14 - 125; 14 - 375; 24 - 0; 24 - 250; 24 - 500; 34 - 125; 34 - 375; 44 - 0; 44 - 250; 44 - 500) (kPa - mg dm-3). The drip irrigation system with semi-automated irrigation control. As analyzed variables were related as vegetative, productive, fruit quality and cherry tomato water use. Results: As leaf and root dry masses and root volume presented increases of 40 to 54% with increase of potassium fertilization up to a potassium dose of 500 mg dm-3. There was a significant relationship between water availability and potassium doses for dry stem and shoot species, which showed increases in production of 74 and 62%, respectively, with a higher production in the combination of 4 kPa and 500 mg dm-3 of potassium when compared to the treatment of 44 kPa and 0 mg dm-3 of potassium. The mean fruit mass, transverse and longitudinal diameter and pulp thickness of fruits showed reductions from 16 to 44% with increasing soil water tension up to 44 kPa. Soluble solids have a higher potassium dose value of 326 mg dm-3. The highest productivity was observed in the soil water availability of 24 kPa and in the potassium dose of 290 mg dm-3. The highest water use efficiency was observed in soil water tension of 44 kPa and potassium dose of 290 mg dm-3. Conclusion: The water availability and the potassium doses influence in an isolated way the vegetative, productive development, quality of the fruits and water use by cherry tomato cv. BRS Iracema.