Construction of a pH/pectinase dual-responsive pesticide microcapsule and adhesive gel patch for sustainable plant disease management

Abstract

Nano-enabled agriculture has greatly improved the yield and quality of agricultural products, and reduced pesticide usage and environmental pollution. However, the building of intelligent nano-pesticides and devices for sustainable disease management still poses severe challenges in modern agriculture. Herein, a smart pH and pectinase dual-responsive pesticide microcapsule was constructed and used to create an adhesive gel patch for disease management. Employing prochloraz (PRO) ionic liquid as a soft template, a metal–phenolic network and pectin were coated to respond to oxalic acid and pectinase secreted by Sclerotinia sclerotiorum during its infection of plants. The preparation of microcapsules was accomplished rapidly, economically, and in an eco-friendly manner in an aqueous environment. The microcapsules exhibited pH and pectinase-dual-responsive traits. The photostability of the microcapsules is 1.33 times that of PRO EW. Fungicidal testing indicated that the control effect of the microcapsules is 1.47 times that of PRO EW. Pot experiments revealed that the control effect of the microcapsules is 2.98 times that of PRO EW. To further enhance the long-term autonomous management and minimize the drug leakage of traditional spraying methods, an adhesive gel patch containing the microcapsules was developed. Using agar hydrogel to stabilize the microcapsules and silicone rubber as a protective layer, the patch can adhere to the leaves under the action of a magnet. With the same dosage of PRO, the management period of the adhesive gel patch was twice as long as that of the spraying method. This study offers a novel strategy for achieving the sustainable management of plant diseases and precision agriculture.