Where do spider mites on greenhouse cucumbers originate? - briefly
Spider mites usually reach greenhouse cucumber crops from external reservoirs such as nearby infested fields, wild host plants, or contaminated transplants. Favorable conditions—high temperature and low humidity—enable rapid population growth within the greenhouse.
Where do spider mites on greenhouse cucumbers originate? - in detail
Spider mites (Tetranychidae) frequently appear on cucumber crops cultivated in protected environments. Their presence results from several distinct entry routes and resident populations that develop under favorable greenhouse conditions.
Primary entry routes include:
- Introduction with infected seedling trays or transplants sourced from external nurseries.
- Transfer via contaminated tools, carts, and ventilation ducts that have contacted infested foliage elsewhere.
- Arrival on workers’ clothing or footwear after contact with infested plants in adjacent fields or greenhouses.
- Dispersal by wind currents that carry mobile adult females into the greenhouse through open vents or gaps.
- Migration from neighboring host plants such as ornamental gourds, wild cucurbits, or weedy species growing in perimeter areas.
Once inside, spider mites exploit the microclimate typical of cucumber production: temperatures above 25 °C, low relative humidity, and steady airflow. These conditions accelerate development cycles, allowing multiple generations per month and rapid population buildup on leaf undersides.
Secondary sources arise from resident colonies that survive between cropping cycles. Overwintering eggs or adult females persist on plant debris, pruning residues, or in cracks of greenhouse structures. Inadequate sanitation and lack of crop rotation facilitate their continuity.
Effective identification of origin points relies on systematic scouting, sticky traps positioned near entry zones, and regular inspection of incoming plant material. Quarantine of new stock, sterilization of equipment, and exclusion of weeds in surrounding areas reduce the likelihood of initial infestation.