Danos à cultura do feijoeiro causados por Helicoverpa sp

Abstract

This work aimed to evaluate the damage caused by Helicoverpa Sp. in bean crop qualitatively and quantitatively. The work was conducted on a private property in a commercial plantation under real cultivation conditions. 10 samples with 10 plants were collected per plot and each one was individually evaluated by assessing the damage caused in the pods, the number of damaged grains and the reduction in productivity caused by the attack of the pest. The percentage of productivity reduction between the plots ranged from 5,9% to 23,40% of loss and the mean reduction of productivity was 15,31%. To control these attacks, the estimate of average cost for the application of agricultural pesticide was around R$ 120.00 per hectare in this cultivation year; whereas the control group with 0% damage would need two additional applications what increases the control cost to around R$ 240.00 per ha. The average market value this bean in agricultural year of assessment was R$ 180.00 per bag (60kg) and the damage caused by the larvae in the present study reached 15,31%. The injury caused by the pest was around R$ 684,00/ha which enables the control of the pest in final stage of development of the crop even that it requires two applications of insecticide. More studies need to be conducted for a more precise opinion as the bean is a new target of the caterpillar and there may be variation of the levels of attack and in the market value of the crop.