Fertirrigação por gotejamento com doses de K na fase reprodutiva do tomateiro tipo italiano

Tomato is one of the most commercialized vegetables worldwide and its production is limited during some seasons of the year. Studying fertilization management of potassium (K), which is the most extracted nutrient by the tomato crop, could improve its growing conditions as well as its nutritional aspect. We evaluated the effect of K doses, applied by drip fertigation in the early reproductive stage, on productivity and content of K, Ca and Mg for Italian-type tomato under greenhouse conditions. Randomized blocks with ten replications was the experimental design the treatments consistingof five K doses (60, 120, 180, 240 and 300 mg/dm3) applied on the beginning of the reproductive phase. Until flower opening, all plots received the standard nutrient solution. The K doses up to 300 mg/dm3 did not influence the productivity of ripe and wealthy fruits, and the contents of K, Ca and Mg in the diagnostic leaves were not influenced by treatments. On some plants we observed a deficiency of Ca on the second to third bunch. Considering the results in this study, doses of K between 60 and 300 mg/dm3 applied in the phase of highest demand (fruit formation), did not influence the productivity of the Italian-type tomato.