Identification and Control Methods of the Wheat Ear Moth

Scientific name Apamea sordens (Hufnagel), belonging to Lepidoptera, Noctuidae. Also known as the wheat ear worm. Distributed in Inner Mongolia, Gansu, Qinghai and other provinces.

Hosts @#@245@#@, barley, highland barley, wheatgrass, Iris lactea, etc.

Damage characteristics: newly hatched larvae first feed on the floral organs and ovary of the ear, and a few feed on the tender inner surface of the glumes; after consuming these they move to cause damage elsewhere. After the 2nd-3rd instar they feed and hide inside the grains; after the 4th instar the larvae move to the flag leaf, spin silk to bind the leaf margins into a tube shape, and after sunset seek out wheat ears to feed.

Morphological characteristics: adult body length 16mm, wingspan about 42mm, whole body grayish brown. Forewings have a distinct black basal streak, shaped like a flying swallow below the midrib; the orbicular and reniform stigmas are silver-gray with black edges; the basal line is a pale gray double line; the subbasal and terminal lines are light gray double lines, jagged; the subterminal line is wavy light gray; the outer margin of the forewing has 7 black dots, with dense fringe hairs; hindwings are light yellowish brown. Eggs are spherical, diameter 0.61-0.68mm, with patterns on the surface. Mature larvae body length about 33mm, head with a light brownish-yellow "eight" (figure-eight) marking; the lateral cranial area has light brown reticulate markings. The pronotal shield and anal plate bear dorsal and subdorsal lines, dividing them into 4 light brown stripe patches; the body is grayish yellow, the dorsal side grayish brown, and the ventral side grayish white. Pupa length 18-21.5mm, yellowish brown or reddish brown.

Life habits: one generation per year, overwintering as mature larvae in the field or under the surface soil of field ridges and under Achnatherum splendens clumps. The following April the overwintering larvae emerge and become active; from late April to mid-May the larvae pupate, with a prepupal period of 6-11 days and a pupal period of 44-55 days. Adults emerge in June-July, with the peak emergence period from mid-June to early July; during the day they hide under wheat plants or grass clumps, and fly out at dusk to feed on wheat pollen or rapeseed. 5-6 days after mating they lay eggs on the inner side of the glume of the first spikelet of wheat or on the ovary, generally in clusters, each cluster ranging from several eggs to 38 eggs; a female moth can lay up to 740 eggs, the egg period is about 13 days, and the larvae molt 6 times, for a total of 7 instars, with a duration of 8, 9 months. The larval damage period is 66, 5 days; newly hatched larvae first feed on the floral organs and ovary of the ear, and after eating them up they move elsewhere; mature larvae have the habit of feeding every other day; 6th and 7th instar larvae, as their bodies grow larger, move during the day from wheat leaves to weeds, spin silk to bind leaves together and hide, and some lurk in the surface soil or soil crevices; in mid-September the larvae begin to overwinter in the loose soil around the roots of wheat stubble.

Control methods: (1) Taking advantage of the adult's phototaxis, install black light traps from early June to late July to trap and kill adults. (2) Before the 4th instar, promptly spray 80% dichlorvos emulsifiable concentrate at 1000-1500 times dilution or 90% crystallized trichlorfon at 900-1000 times dilution. (3) After the 4th instar they hide during the day, so when control is needed the above insecticides should be sprayed after sunset. (4) At wheat harvest, pay attention to killing the larvae under the wheat bundles to reduce the overwintering population base. (5) Set up trap strips. After adult emergence and before mating, this insect mainly feeds on rapeseed nectar, and its peak period coincides with the local large-scale rapeseed full-bloom period; it also likes to lay eggs on the ears of early-maturing highland barley, wheat and other crops. In the same wheat field, the most eggs are laid on mixed highland barley and early-maturing wheat, which suffer the most severe damage. Based on this habit, planting highland barley and early-maturing wheat around the wheat field and in the middle of the field according to specifications can attract adults to lay eggs. At the same time, because the wheat ear moth larvae have the habit of damaging the ear grains inside the glumes before the 3rd instar and moving to feed after the 4th instar, after the trap strips have received eggs and before the larvae move, promptly uprooting or spraying the trap strips will greatly reduce the insect source, achieving the purpose of protecting the main field wheat from damage.