Production of groups of tomatoes in substrate at different concentrations of phosphorus

Abstract

The development of production technologies, such as greenhouses, was highlighted in the growth of horticultural crops. However, these products are often offered without basic instructions to farmers who can generate financial losses. One outstanding production technology is substrate cultivation, which would be very useful in the cultivation of protected plants. Like this, in order to evaluate the effects of different doses of phosphorus on the production of tomato groups grown in substrate under greenhouse conditions, a randomized complete block design was used in a 2 x 5 factorial scheme, with two tomato groups: Santa Cruz "Debora Max" and Cherry "Coco" x five rates of P 2 O 5 (0; 33; 66; 99 and 132 g; 10 L of nutrient solution) with four replicates. The results showed that the electrical conductivity inside the Slabs is not homogeneous, being recommended to wet the substrate inside the slabs, before the planting to reduce the electrical conductivity. In relation to phosphorus efficiency, the highest tomato yield was for the 6.6 g L -1 phosphorus dose for the two Santa Cruz and Cherry groups. The main advantage of using slabs in tomatoes is the efficiency of the phosphorus used in the first planting.Key words: Lycopersicon esculentum, substrate, slabs, phosphorus, fertilization. INTRODUCTIONThe tomato Lycopersicon esculentum Mill is one of the main vegetables produced in Brazil, arriving at the market in an in natura or processed way. The tomato production chain reached more than 37 million tons in 2010, for global parameters, consolidating the chain as one of the main agribusiness. By 2016, according to estimates by the World Tomato Processing Council, the amount should reach more than 39.3 million tonnes. Most of the production, near 97%, is concentrated in the 10 largest producers, which accumulate around 34.1 million tons. Brazil is in eighth place with 1.25 million tons produced (Carvalho et al., 2016). In order to improve tomato yield and meet increasing demand, new technologies have been adopted, among which the production in a protected environment stands out (Cararo and Duarte, 2002). The cultivation in a protected environment provides better accommodation of the plants against undesirable climatic factors, reducing the risks of tomato cultivation, besides allowing the production of fruits in times not favorable to the conduction of planting in the open field (Alvarenga, 2004). The technique of cultivation in protected environment using substrate has been generalized to allow better nutrient absorption, higher productivity, better product quality and facilitation of the implementation of cultural practices (Gul et al., 2005). Gualberto et al. (2002) comments that this system has many advantages that include the high quality and yield of the crop, lower fertilizer losses and the better use of water, besides the reduction in environmental pollution and greater control and efficiency in the process productive. Riviere and Caron (2001) report that substrate cultivation is effective in protecting crop path...