Plant cell piercing by a predatory mite: evidence and implications

Area of Science:

• Agricultural Entomology
• Plant-Mite Interactions
• Beneficial Arthropods

Background:

• Omnivorous arthropods provide natural pest control by feeding on plants when prey is scarce.
• The feeding mechanisms of phytoseiid mites on plant cell-sap and their impact on plants are not well understood.

Purpose of the Study:

• To investigate the feeding mechanism of the omnivorous predatory mite Euseius scutalis on pepper plants.
• To determine the influence of Euseius scutalis feeding on plant tissues and growth.

Main Methods:

• Scanning electron microscopy (SEM) was used to examine penetration holes in pepper foliage and wax membranes.
• Controlled growth chamber experiments were conducted to assess the impact of Euseius scutalis on pepper plant growth.

Main Results:

• Euseius scutalis penetrates plant epidermal cells and wax membranes, creating teardrop to oval holes (2-5 µm).
• The mite utilizes a similar penetration mechanism for feeding on pollen and plant cell-sap.
• High populations of Euseius scutalis negatively impacted the growth of young pepper plants.

Conclusions:

• Euseius scutalis employs a cell-piercing feeding strategy on plants, similar to its pollen-feeding mechanism.
• While beneficial for pest control, high densities of this mite can harm young plants.
• Further research is needed to optimize the use of plant cell-sap feeding predators in agriculture.