Fungicides of the strobilurin chemical group gained new perspective, because the benefits obtained by the action of positive physiological effects in plants. The study aimed to verify the effect of pyraclostrobin in the content of photosynthetic pigments, nitrogen and activity of the enzyme nitrate reductase in tomato plants cv. Micro-Tom cultured with different nitrogen rates. At 21 days after transplanting (DAT) the plants were subjected to treatments: complete nutrient solution without pyraclostrobin; complete nutrient solution with pyraclostrobin; nutrient solution 1/2 ionic strength of the nitrogen without pyraclostrobin and nutrient solution 1/2 ionic strength of the nitrogen with pyraclostrobin. The application of pyraclostrobin was repeated at 35 DAT. At 28 and 42 DAT was determined content of photosynthetic pigments and total nitrogen and nitrate reductase activity. The application of pyraclostrobin promoted an increase in pigment only at 28 DAT, plants with low nitrogen supply. Two applications of pyraclostrobin did not influence the nitrogen content and nitrate reductase activity in tomato plants cv. Micro-Tom grown in nutrient solution Hoagland and Arnon.
fungicides; strobilurin; photosynthetic pigments; nitrate reductase