Silicon and acibenzolar-s-methyl to induce resistance against Bemisia tabaci biotype B and the effects on common bean plants

Present study is aimed to evaluate the effects of silicon and acibenzolar-s-methyl (ASM) application on the oviposition/feeding preference of the whitefly, Bemisia tabaci biotype B during development of bean plants. A completely randomized blocks design was used with three treatments and 10 replications. The following treatments were applied: T1 - application of 500 mL of 1% silicic acid solution in the soil around the plants (drench) (2 ton SiO2 ha-1); T2 - spraying (foliar) of ASM (Bion®) at the rate of 0.125 g L-1 of water (25 g of the commercial product ha-1); and T3 - application of 500 mL of water in the soil around the plants (control). Plants were infested with 100 adults per pot in a greenhouse. The diameter and the dry weight of the aerial part of the plants were determined in one plant per pot. At the fourth day after infestation, the number of eggs was recorded in the third and fourth completely developed apical leaves. Thirteen days after the removal of the adults, the evaluation of the number of third/fourth instar nymphs was performed. There was no significant reduction of the feeding/oviposition preference and on the development of bean plants following application of silicon or ASM. However, the number of nymphs was reduced on plants treated with both resistance inductors, constituting a promising alternative tactic for the management of the whitefly.