Department of Plant Sciences

This work aimed to evaluate the efficiency of boron and calcium rates, via leaf application, on sunflower grain yield and morphologic plant parameters. The experiment was carried at Federal University of Technology – Paraná, Campus Dois Vizinhos, PR, Brazil, during the period of September, 2008 to Abril, 2009. The soil of experimental area is an Oxisol. The experimental design was as completely randomized blocks, with four replicates. Plots were composed of six meters long and five seed lines of 0.9 meters spaced. The genotype used was Agrobel - La Tijereta. Treatments were: (i) Witness; (ii) 2000 g of B ha-1 via soil; (iii) 250 g of Ca ha-1 in leaves; (iv) 500 g of Ca ha-1 in leaves; (v) 750 g of Ca ha-1 in leaves; (vi) 1000 g of Ca ha-1 in leaves; (vii) 250 g of B ha-1 in leaves; (viii) 500 g of B ha-1 in leaves; (ix) 750 g of B ha-1 in leaves; and (x) 1000 g of B ha-1 in leaves. Soil and leaves treatment with boron were made with Sodium Octaborate. Calcium treatments were made with Calcium Chloride. It was analyzed: number of achenes per plot, plant stature, number of green leaves, achene’s diameter, mass of one hundred grains and grain yield. No answer to calcium and boron leaf application was observed on the present study, probably as consequence of low soil water availability during sunflower growth season, what resulted on low mean sunflower grain yield and compromised plant morphological parameters.