What does currant look like when affected by a bud mite? - briefly
Infested currant buds appear deformed, swollen, and often turn pale or brown, with emerging shoots stunted and sometimes covered in fine webbing. Leaves may show stippled discoloration and drop early.
What does currant look like when affected by a bud mite? - in detail
Currant vines attacked by the bud mite display a series of distinctive visual changes that can be recognized early in the growing season.
The most evident symptom is the formation of abnormal buds. Affected buds are often swollen, misshapen, and may appear hollow or cracked at the surface. The tissue inside the bud turns a pale green or yellowish hue, contrasting with the surrounding healthy green tissue. In some cases, the bud tip becomes necrotic, showing brown or black discoloration that spreads inward.
Leaves emerging from infested buds are typically smaller than normal and display a mottled pattern. The margins may be irregular, and the leaf surface can develop a silvery or dusty coating caused by the presence of numerous mite exuviae. Stipules are often reduced or absent.
Shoot growth is stunted; new shoots are short, thin, and may exhibit a twisted or corkscrew shape. The internodes are compressed, giving the shoot a crowded appearance. In severe infestations, shoots may die back entirely, leaving only a few healthy shoots on the plant.
Fruit set is reduced because damaged buds fail to develop properly. When fruits do form, they are often misshapen, with a rough surface and uneven ripening. The skin may show patches of discoloration ranging from light green to brown.
Diagnostic clues include the presence of tiny, translucent mites (approximately 0.2 mm) on the bud surface, often visible under a hand lens. The mites congregate near the bud axis and leave fine webbing that can be seen as a faint, silky film.
Management relies on early detection and timely application of miticides or horticultural oil, combined with cultural practices such as removing and destroying heavily infested buds and maintaining good air circulation to discourage mite proliferation.