Septempunctata cotton insect, also called the boll budworm, Latin name: Helicoverpa armigera Hubner, the English name Cotton bollworm, noctuidae.
Adults: Taupe medium-sized moth, body length 15-20mm, the wing exhibition 31-40mm, compound eye ball, green ( relatives of tobacco budworm compound eye black ). Female moths of red brown to grayish brown, grey of cotton bollworm moths, wing, can be used as Noctuidae adults mode, the forewings, outside the lines with dark grey band, with 7 small white spots, renal veins, annular dark brown. Hind wing pale, along the outer edge of a dark brown broadband, broadband Central has 2 connected white. Hind wing leading edge 1 crescent brown spots.
Egg: hemispherical, high 0.52mm, 0.46mm, the top surface is slightly raised; vertical and horizontal lines, vertical lines is seen from the top of 12, central 2 vertical lines which are clamped between 1-2 short lines and 2-3 fork, so viewed from the middle have 26-29 vertical lines.
The larvae: a total of 6 age, 5 age ( sometimes feeding peas, sunflower disk ), aging 6 instar is about 40-50mm long, Brown is not obvious head markings, colour of larva and changeable, is divided into 4 types: 1) color is reddish, dorsal line, subpopulations of dorsal line valve line brown, white, Mao Tuhei color. 2) color of yellow and white, the back line, subpopulations of dorsal line green line white hair, valve, with the same color. 3) color is light green, the back line, subpopulations of dorsal line is not obvious, the valve line white, hairy processes with the same color. 4) color is dark green, the back line, subpopulations of dorsal line is not too obvious, valve yellow. The valve at the top of a brown vertical belt, is a sharp spinules arranged ( tobacco budworm spinules blunt circle, not arranged in a line ). Larval abdominal first, 2, 5 Section 2 each a process especially apparent.
Pupa: long 17-20mm, fusiform, reddish brown to dark brown, ventral terminal has a pair of buttocks thorn, thorn separated from the base. The valve is large, round hole plate is in a cylindrical protuberance is higher, abdominal section 5-7 stippled semicircular, thick and thin ( tobacco budworm pores small, spiny base closure, round hole plate is not high, section 5-7 stippled fine, a semicircle, there are round ). Embedded 5-15cm pupation, covering soil cocoon.
The cotton bollworm in Southern China region has 6 generations every year, with the pupa in rhizosphere soil in vicinity of parasitic. In the next year after eclosion and oviposition of. The first generation of the tomato, pea crop damage. Second generations later in the field with overlapped generations. Adult day perched on the back of the leaves and the shade, the twilight began activities, learn from plant nectar as nutritional supplements, flying ability, have phototaxis, spawning when there are strong twigs. Egg powder production in the host leaves, fruit stalk etc., each female generally lay eggs more than 900 tablets, up to more than 5000 tablets. The newly hatched larvae that inhabit leaf does not eat does not move, second days to growth point, but the damage was not obvious, third days into the 2 age, beginning eats, shoots, flower buds, fruits, can turn plant damage, each larva can be 3~5 fruit borer. After 4 years of binge eating stage. Mature larvae. 5~15 cm deep soil chamber pupation.
Recommended prevention methods: when the cotton bollworm 100 strain rate is 5～ 10 generation, two generation is 15 ～20, three generations of 25 heads, each with 10000000000 /ml 667m2 spores Empedobacter brevis suspending agent from 80 to 100 ml versus 45 kg water spray mist. The eggs hatch into larvae season before the two th, application effect is best. The two generation of eggs on top of leaves, should adopt the heart of pricking or only spray cotton top, three or four generation eggs were scattered around, can be sprayed cotton. |
