AGRONOMIC PERFORMANCE OF SUNFLOWER CULTIVARS IN TWO PLANTING DATES IN THE NORTH PLATEAU OF SANTA CATARINA STATE

Abstract

In several Brazilian regions, the sunflower crop (Helianthus annuus) has been cultivated as a new economic alternative. The growth in the area planted with this crop is due to incentive of the National Program of Biodiesel. Thus, the objective of this work was to evaluate the grain yield and some agronomic characters in sunflower cultivars in two planting dates in “safrinha”. Two experiments were carried out in Papanduva, North Plateau of Santa Catarina State, Brazil. The experimental design used was the randomized blocks with three replicates. Were evaluated twelve sunflower genotypes in the first planting date (January) and 13 genotypes in the second planting date (February). Development cycle observed was between 93 to 107 days in function to the cultivar and planting date. In the second planting date, some cultivars showed high levels of lodging (until 29%) and plant breakage (until 42%). In the first planting date, 10,8% of the bagged flowers were infected by Sclerotinia sclerotiorum. In the second planting date, this level increased to 45%, affecting directly the grain yield, 1861 and 618 kg ha^{-1, in the first and the second planting date, respectively.}