Potassium silicate on the productivity of Opuntia stricta Haw and the infestation by Diaspis echinocacti

Forage cactus has gradually gained economic importance and is a potential alternative for producers in the semiarid region, as it can be used for various purposes for both humans and animals. However, its cultivation is affected by several types of insect pests that affect its production, especially the scale insect. Thus, this study aimed to test the influence of potassium silicate on forage cactus productivity and scale insect infestation. The experimental design used was randomized blocks in a factorial scheme with repeated measurements over time of 4 x 4 + 1, corresponding to four concentrations of potassium silicate (0, 5, 9, 18, 28 ml L-1) and four application times (0, 90, 180, 270 days) and an additional control treatment (without silicate application) with four blocks, containing five plants as the experimental unit. At 365 days after the start of the experiment, the plants of the experimental plot were used to perform biometric and infestation analyses. Morphoagronomic variables of the palm were considered, and the level of scale mealybug infestation was also evaluated. There was no significant difference between the different times of product application. The applications of potassium silicate benefited the forage palms, especially at a concentration of 28 mL L1, which provided greater dry matter productivity (84.78 t ha1) and lower scale mealybug infestation (55.4%). It is concluded that there is evidence that the application of potassium silicate induces resistance to scale mealybug with a lower level of infestation in the cladodes.