ADUBAÇÃO MINERAL E ORGANOMINERAL ASSOCIADA A ÁCIDOS ORGÂNICOS NO CULTIVO DO TOMATEIRO INDUSTRIAL

Abstract

Tomato is one of the most consumed vegetables in the world. Considering tha the objective of this study was to evaluate the fertilization efficiency with mineral fertilizer; organomineral, in the presence of humic and fulvic acid, as an alternative management for the industrial tomato cultivation. The experiment was carried out at the Federal Institute of Education, Science and Technology Goiano - Morrinhos Campus, located at BR-153 Km 633. The geographic coordinates of the place are 17º48'45" South, 49º12'14" West and 910 m altitude. The tomato cultivar studied was the hybrid Heinz 9553. The treatments consisted of three types of fertilizers in the transplant: T1 - formulation of mineral fertilizer containing KCl; T2 – formulation of mineral fertilizer with monoammonium phosphate (MAP); T3 – formulation with organomineral fertilizer containing potassium sulfate (K2SO4); both with and without humic and fulvic acids. The design used was randomized blocks in a factorial scheme of 3 x 2 with five replications, totaling 30 plots. The photosynthetic rate (PR), stomatal conductance (SC), respiratory rate (RR), internal and external CO2 ratio (Ci/Ca), and electron transport (ET) were evaluated as physiological characteristics, production and physical-chemical characteristics of the fruits, and the foliar contents nutrients, such as potassium (K), phosphorus (P), calcium (Ca), magnesium (Mg), copper (Cu), iron (Fe), zinc (Zn) and manganese (Mn). The results demonstrate that the formulation with organomineral+ K2SO4 had the highest means for PR, SC, RR, and Ci/Ca and the lowest for ET. And even greater fruit production and average like KCl and MAP minerals for the physical- chemical characteristics of the fruits. Regarding leaf nutritional contents, Cu obtained 9.17 mg kg-1 in MAP mineral. For Mn, the organic acids addition had the lowest average of 47.12 mg kg-1 . For Mg and Zn, the organomineral stood out in the means obtained, in the absence of humic and fulvic acids, in relation to KCl and MAP. In the absence of humic and fulvic acids, the organomineral-containing K2SO4 formulation is the best alternative for industrial tomato base fertilization.