Silicon doses, through soil, in the induction of resistance to Spodoptera frugiperda in the bean plant.
This study aimed to verify the effects of different doses of silicon in bean induction of resistance to S. frugiperda. It was adopted a completely randomized design with four treatments and five repetitions. The treatments were represented by silicon levels: 0 kg ha-1; 50 kg ha-1; 100 kg ha-1 and 200 kg ha-1. The potassium silicate was applied to the soil with the planting fertilization. The parameters evaluated were: survival of larvae after 48 hours, the larval survival, biomass of larvae at 14 days of age, larval development period, biomass pupae viability of larval and pupal stages and feeding non-preference of the first instar larvae. The greatest accumulation of foliar silicon in bean (01.04%) was observed for the dose of 111.1 kg ha-1 silicon. It follows that larval survival not affected by fertilizer bean plants with silicon (p = 0.7045). However, the larval development period was increased as the increase of silicon doses. The non-preference of S. frugiperda larvae increased proportionally to the silicon doses. A fertilizer with potassium silicate succeeded in control of S. frugiperda in dosages of 100 and 200 kg ha-1, for even it not being an accumulator culture of silicon, it obtained a satisfactory response to fertilization, decreasing the preference of caterpillars and increasing their larval development period.