Silicon and boron on cauliflower induce attractiveness and mortality in Plutella xylostella

Abstract

Background: Boron (B) and silicon (Si) are fundamental for brassica nutrition, and in some cases, they have potential as an insecticide. Plutella xylostella (L.) (Lepidoptera: Plutellidae), one of the most economically important agricultural pests, is difficult to control due to the resistance to insecticides and the absence of alternative control methods. Results: Cauliflower leaves sprayed with Si and B showed a higher concentration of the beneficial element and micronutrient, respectively. When evaluating the firmness of the cauliflower leaves, it was found that the plants with leaf sprayings of Si and B did not differ statistically from each other. However, they showed an increase in firmness, in relation to the plants of the control treatment. Leaf spraying of Si and B on cauliflower did not influence the number of eggs/female. The attractiveness index showed that both Si and B applications stimulated the presence of second instar larvae, being more stimulating in relation to the control treatment. However, the use of Si and B in isolation showed a positive result, since it caused high mortality in diamondback moth larvae compared to the control treatment. Conclusion: The application of both foliar fertilizers positively affects the attractiveness index of the larvae, being attractive; however, both Si and B caused high mortality (similar to 80%). The results showed that Si and B have the potential to control P. xylostella and serve as a basis for alternative pest management in brassica crops. (C) 2022 Society of Chemical Industry.