Identification and Control Methods for the Fungus Gnat Pest of Lingzhi Mushroom

The fungus gnat (MycophilafungicolaFelt), also known as the mushroom-loving gall midge, or mushroom gnat. It belongs to the order Diptera, family Cecidomyiidae.

1. Morphology and habits: The adult is small, about 1 mm long. The head, thorax and back are dark brown, while the rest is grayish-brown or orange-red. The head is small, the compound eyes are large and connected left and right, and the antennae are slender and bead-like, with 11 segments, each segment bearing whorls of radial fine hairs; the male's antennae are longer than the female's, and the wings are broad and hairy. The female's abdomen tapers to a pointed tip, while the male's abdomen has a pair of pincer-like claspers. The egg is kidney-shaped, about 0.3 mm long, milky white to light brown. The larva is maggot-like, with 13 body segments, legless, orange-yellow, pale yellow or white. The pupa is a naked pupa, averaging 1.07 mm long and 0.27 mm wide, orange-red, with 2 hairs at the top that serve as breathing tubes.

Both adults and larvae are phototactic, and population density is high in brighter places. The larvae prefer moisture, move freely in damp places, and can survive in water for many days. Under conditions of high temperature and high humidity, they reproduce one generation per week. Therefore, they can proliferate in large numbers within a short time.

2. Damage: The larvae damage the mycelium and fruiting bodies of lingzhi. During the spawn-running period they damage the substrate, and after casing soil is applied they move into the soil layer, damaging the downy mycelium and fruiting body primordia; after being damaged, the mushroom buds turn yellow, wilt and die.

3. Control methods

(1) Install gauze screens on the doors and windows of the growing room to prevent adults from entering.

(2) Clear away discarded dirt and waste materials, maintain hygiene, and spread lime to keep the environment dry.

(3) When fungus gnats are found, spray with 1% permethrin or 1000-fold 50% phoxim to kill them.

(4) When sterilizing the casing soil heap, spray the surface with 500-fold dichlorvos solution, then cover with plastic film to kill eggs, pupae and larvae.

(5) Taking advantage of the adults' phototaxis, install a "edible mushroom high-voltage electrostatic insect-killing lamp" to trap and kill them. Recently, the Yuyao City Edible Mushroom Research Institute in Zhejiang designed and produced a novel high-voltage electrostatic insect-killing lamp based on edible mushroom small flying insects. This product has the characteristics of good insect-killing effect, convenient installation, safe use, low power consumption, long service life and small size.