An environmentally benign oil dispersion/phytoextract system for improved retention upon foliage and control of aphids in spice crops

Abstract

About one-third of agricultural production relies upon chemical pesticides. The major part of applied pesticides is lost due to poor retention characteristics, whereas the retention is related to pesticide utilization efficiency. The drift pesticides create substantial environmental contamination and are a primary concern because of their high persistence and toxicity to humans and non-targets. Coupling bio-pesticide and suitable delivery systems to optimize targeting and uptake will enable the design of suitable agrochemicals that combine optimal safety, sustainability, and functionality profiles. We present a strategy to address the issue by taking advantage of oil dispersion (OD) as a delivery system for loading leaf phyto-extract of an indigenous plant (Dalbergia sissoo). The chemical profiling of phyto-extract performed by GC-MS revealed the presence of hydrocarbons, fatty acid methyl esters, and their derivatives, including majorly Glycidyl oleate, Cinnamyl linoleate, whereas LC-MS analysis briefed the presence of compounds; Ferulic acid and a chalcone flavonoid- Isoliquiritigenin. The OD was developed via a two-step process; dispersion followed by wet grinding, which displayed shear-thinning rheological behavior. Upon spraying on leaves, the OD carrier could achieve enhanced wetting and spreading on the foliage. Driven by the additive-based interactions, OD improved pesticide retention and wash resistance, which was evident by the fluorescent labelling of the formulation. The leaf extract-loaded OD possesses a 9-day residual effect and excellent efficacy in controlling Aphids, comparable to synthetic insecticide. Overall, OD-loaded phyto-extract provides an effective strategy for prolonging pesticide retention and reducing pesticide loss in agro-production, both of which are desirable for a cleaner and pollution-free environment.