Bulb Mites – Rhizoglyphus echinopus – Rhizoplyphus robini – Rhizoplyphus hyacinthi – Rhizoplyphus engeli

Bulb Mites (Rhizoglyphusechinopus, Rhizoplyphusrobini, Rhizoplyphushyacinthi, Rhizoplyphusengeli  Common Name: Bulb Mites Latin Name: Rhizoglyphusechinopus, Rhizoplyphusrobini, Rhizoplyphushyacinthi, Rhizoplyphusengeli Appearance: Adult: Bulb mites have four pairs of legs and reach a mature length of 0.5 to 0.9 mm. Their bodies are shiny, white, and somewhat transparent, with reddish-brown appendages. Egg: The egg is white and transparent, measuring 0.12 mm in length and ellipsoidal. Larva:  The larva is 0.15 to 0.2 mm long when it hatches and 0.25 mm long when fully mature. Larvae are white and oblong, with just three pairs of legs and no genital suckers. Territory: Since their discovery in Europe, bulb mites have spread across the United States, Canada, Japan, and the Bermuda Islands. These mites are easily transferred in contaminated bulb shipments. Host plants: Bulb mites have been seen eating the iris, lily, narcissus, Gloriosa, Hippeastrum, Eucharis, orchid, hyacinth, and tulip bulbs as dahlia tubers and freesia and gladiolus corms. These mites also infest vegetable bulbs. Damages caused by Bulb Mites: Bulb mites access the bulb and feed in protected cavities, where fungus and bacteria can cause the bulb to decompose. They are linked to the spread of the Fusarium, Stromatinia, and Pseudomonas bulb diseases. Freesia, hyacinth, lilies, narcissus, onions, and subterranean peony rhizomes are among the bulb species affected. Freesias are particularly vulnerable because they require high temperatures to overcome dormancy, allowing bulb mite populations to increase rapidly. Lilies are attacked from below, stunting their development. The plants will tumble if they are fed at ground level. Life history and habits: The female can live for up to a month after mating, whereas the male dies soon after. The white eggs are small and deposited singly on the bulbs. It takes 2 to 7 days for them to hatch. At a rate of six to eight eggs each day, a female can lay 50 to 100 eggs. A whole life cycle can be completed in 2 to 4 weeks under ideal conditions. Due to overpopulation, the bulb mite develops an extra nymphal stage termed the hypopus stage in addition to the larval and two nymphal phases. This mite stage is small, round, and has eight legs. It does not eat. Its thick brown cuticle protects it from the elements and allows it to thrive in harsh situations. By attaching itself to items and insects such as adult whitefly, thrips, fungus gnat, or beach fly, visiting the rotten bulbs, the mite can travel and be transported great distances. The hypopus stage can last up to two weeks before molting into the deutonymph, which then molts into the adult stage when it finds a suitable host plant.