Bulb mite

Systematic position. The bulb mite, genus Sancassania, belongs to the order Acariformes and the family Acaridae. These are microscopic soil-dwelling mites that thrive in organic-rich environments and are notorious pests of underground plant organs, often found in both agricultural fields and storage facilities.

Affected crops. Sancassania mites primarily target bulbous and cormous plants. Economically significant damage is observed in onions, garlic, and various ornamental bulbs including tulips, lilies, hyacinths, and gladioli. They can also feed on seedlings and plant debris, facilitating the spread of various plant pathogens.

Biology and life cycle. These mites are highly sensitive to humidity and temperature. They reproduce rapidly in warm, damp conditions. A critical phase in their development is the 'hypopus' stage—a resistant, non-feeding nymphal stage that can attach itself to other insects or tools, facilitating the spread of the infestation to new fields or storage units.

Damage and pest status. The damage usually starts at the basal plate (the bottom) of the bulb. The mites pierce the tissues to feed, which leaves them vulnerable to secondary fungal and bacterial invasions.

• Stunted growth of the plant.
• Yellowing and wilting of the foliage.
• Rotting of the basal plate and root loss.
• Total destruction of stored bulbs within a few months.

Protection measures. Integrated Pest Management (IPM) is essential for controlling Sancassania. Key practices include strictly avoiding the planting of infested bulbs, rotating crops with non-host species, and maintaining low humidity in storage areas. Chemical control involves soaking planting material in acaricidal solutions before planting, combined with appropriate soil preparation to reduce the initial pest population.