SOURCES AND DOSES OF NITROGEN EN THE DESENVELOPMENT OF CULTURE ENDPRODUCTIVITY OF SWEET CORN (Zea mays convar. saccharata var. rugosa)

This work aimed to assess the effects of different sources and dosages of nitrogen (N) in the development and productivity of sweet corn (Zea mays convar. saccharata var. rugosa). The experiment was carried out at Sao Domingo Farm, in Palmeiras de Goias, state of Goias, during the agricultural season of 2010-11. It was used the experimental design of random blocks with parcels subdivided in three replications, which required 36 treatments, the area of each parcel being of 25.6 square meters (3.2 m/8 m). Each N source (Novatec T, urea, ammonia sulfate) corresponded to a parcel. The sub-parcels were formed by the following N dosages: 0, 50, 100, and 150 kilos per hectare. During the flowerage period, the following morphological elements were assessed: plant and ear height and stalk diameter. The harvest took place in March 3, 2011, between the milk grain and dough grain stages. Ears were cropped and then identified through treatment. After that, the following variables were assessed: ear and cob diameter, number of grain per row, grain and ear length, plants final population per hectare, number of ears per hectare, and corn straw green mass per hectare. The growing of sweet corn in the soil and climate characteristics of Palmeiras de Goias responded positively to the increase of nitrogen fertilizer no matter what the N source may be.