Arctoseius semiscissus

Arctoseius semiscissus is a species of predatory mite belonging to the family Ascidae, order Mesostigmata. While many species in this group are considered beneficial, under specific greenhouse conditions, Arctoseius semiscissus can behave as a pest, causing significant damage to the roots and stems of young seedlings and ornamental plants.

The biology of this mite is highly dependent on environmental conditions, particularly soil moisture and the presence of organic matter. It thrives in high-humidity habitats, where it can rapidly complete its life cycle from egg to larva, nymph stages, and adult. Its ability to colonize soil and substrates makes it a difficult pest to detect until visible damage occurs.

The primary damage caused by Arctoseius semiscissus includes feeding on root tissues and the root collar of seedlings. By compromising the root system, the mite stunts plant growth and makes the plant susceptible to secondary pathogens, such as soil-borne fungi and bacteria, which cause further decay and wilting.

Key impacts on crops include:

• Root system destruction in young vegetable seedlings;
• Stunting of ornamental plant development;
• Increased incidence of root rot due to feeding wounds;
• High mortality rates in greenhouse-propagated cultures.

Effective management requires strict adherence to agricultural hygiene. Sterilizing growing media and greenhouse soil before planting is critical. Implementing proper irrigation management to avoid excessive substrate moisture helps in creating a less favorable environment for the mites. If infestation levels exceed economic thresholds, the application of targeted soil-active acaricides is recommended to minimize crop loss.