Preparation of chitosan/sodium tripolyphosphate@nano‐silica sol microcapsule suspensions and their application in soybean cyst nematode control

Abstract

AbstractFosthiazate is a common insecticide for root‐knot nematode control, but it has a short shelf life and is prone to decomposition. In order to improve the stability and prolong the release time, this experiment used the ionic gel method to cross‐link chitosan with sodium tripolyphosphate and added nano‐silica sol to prepare microcapsules suspensions. The optimal preparation parameters for the preparation of chitosan/sodium tripolyphosphate@nano‐silica sol microcapsulated suspensions were optimized by single factor experiments and response surface analysis, and the encapsulation efficiency reached 61.3%. The highest control effect in greenhouse pots can reach 84.1%, and the optimal concentration was 2 g/m2 mixed with soil, which increased stem length, root length and fresh weight by 81.1%, 47.7% and 62.5%. The study showed that the microcapsules of chitosan cross‐linked with sodium tripolyphosphate and added with nano‐silica sol could significantly prolong the release of Fosthiazate, which also provided a positive effect on soybean cyst nematode control.