The behavior of sunflower cultivars was evaluated in relation to the attack of Chlosyne lacinia saundersii, under field conditions. The following parameters were evaluated: number of larvae per plant, number of larvae per linear meter of plants, percentage of attacked plants and percentage of defoliation. The results were as follows: the most suitable methods for evaluating the insect infestation were the percentage of attacked plants and the number of larvae per linear meter of plants; the less infested sunflower cultivare were 'Cargill-33', 'Contissol', 'Issanka-F', 'PIGB', 'Uruguai' and 'Contissol-621', while 'Contissol-711', 'Contissol-112', and 'Ruinano-P/ were the most infested ones. The occurrence of C. lacinia saundersii was higher in the second period of cultivation (February to June) than in the first (October to February).
crop resistance to insects; Chlosyne lacinia saundersii; Helianthus annuus; sunflower