The Application of L-valine Derivatives in Pesticide Sustained-release systems

Derivatives of L-valine have various potential applications in pesticide slow-release systems, specifically as follows:

Enhancing pesticide stability: For example, poly(vinyl alcohol)-valine derivatives can be used to prepare nanogel suspensions. This nano-formulation can fully encapsulate pesticides and exhibit good stability in low-temperature, high-temperature, or water with different hardness levels. It can also enhance the retention of pesticide solutions on leaf surfaces. Meanwhile, as water evaporates, the concentrations of poly(vinyl alcohol)-valine and surfactants increase, which promotes the formation of a coacervate layer, providing excellent light resistance for agricultural chemicals and extending the half-life of pesticides under light exposure.

Enabling on-demand pesticide release: The aforementioned nanogels prepared from poly(vinyl alcohol)-valine derivatives respond to laccase in the digestive tract of lepidopteran pests, allowing for on-demand pesticide release. When pests feed on crops sprayed with this formulation, the nanogels come into contact with laccase in the pests' digestive tracts, thereby releasing the pesticide. This improves the pest control effect, reduces unnecessary release of pesticides into the environment, and increases utilization efficiency.

Improving pesticide conductivity: The coupling of phenazine-1-carboxylic acid with L-valine yields a phenazine-1-carboxylic acid-L-valine conjugate with superior phloem transportability. Compared to phenazine-1-carboxylic acid, which lacks phloem transportability, this conjugate can be transported downward in wheat plants and from the main stem to tillers. This facilitates the control of plant root and vascular diseases through foliar spraying, improves pesticide use efficiency, and expands the application range of pesticides.

Inducing plant insect resistance: Menthyl valinate hydrochloride (MV-HCl) can act as a plant defense enhancer to induce insect resistance in crops. Treating the soil or leaves of potted tomatoes and lettuce with MV-HCl solution increases the transcription level of plant defense genes, significantly reducing leaf damage caused by Spodoptera litura and the oviposition amount of Tetranychus urticae. Additionally, when attacked by Tetranychus urticae, the treated plants show enhanced ability to attract their predatory mite Phytoseiulus persimilis, which promotes both direct and indirect defense of plants and is beneficial for organic crop production.