What are the control methods for the cotton stem borer (Zeuzera coffeae) in cotton?
What diseases occur during the boll stage of cotton? How should they be controlled? How are cotton boll-stage diseases controlled? The occurrence of cotton boll-stage diseases is closely related to climate, variety, insect pests, and cultivation techniques during the growth period. Therefore, the control of cotton boll-stage diseases should adopt comprehensive control measures focused on cultivation management, combined with chemical protection. (...
**How do you control the cotton stem borer (Zeuzera coffeae) in cotton?Scientific name Zeuzera coffeae Nietner, Lepidoptera, family Cossidae.
Aliases: coffee carpenter moth, coffee leopard moth, leopard-print carpenter moth, coffee black-spot carpenter moth.
Distribution: eastern and southern China; in Shanghai and Taiwan, China, it mainly damages cotton and trees.
Hosts: cotton, tea, mulberry, jute, castor, coffee, lychee, longan, citrus, pear, persimmon, loquat, peach, grape, jujube, etc.
Damage characteristics
The larvae bore into and feed on the stems of cotton and jute, causing the upper part or the entire plant to wither and die; when damaging mulberry, tea, and fruit trees, the larvae bore into the xylem of branches and trunks, gnawing outward at intervals to form a row of frass holes, mostly tunneling upward along the pith, causing broken branches or wilting.
Morphological characteristics
Adult body length 11-26mm, wingspan 30-50mm, male smaller than female, body grayish white. Female antennae filiform; male basal half plumose, tip filiform; all black, covered with white scales. Thoracic dorsum with 6 blue-green spots arranged in 2 longitudinal rows; each abdominal segment dorsally with 3 transverse rows of blue-green longitudinal stripes, each side with 1 blue-green spot, venter with 3 spots of the same color. Forewings and hindwings densely covered between veins with blue-green short oblique streaks, outer margin vein ends as spots. Hindwing spots lighter in color. Female hindwing with 1 larger blue-green round spot at the middle. Egg elliptical, length 1mm, cream-yellow to brown. Larva body length 20-35mm, red, head yellowish brown or light reddish brown, pronotal shield yellowish brown to black, near posterior margin center with 4 rows of comb-like tooth rows pointing backward, ventral prolegs with biserial circles of crochets, anal plate dark brown. Pupa length 16-27mm, brown and glossy, abdominal segments 2-7 each with 2 transverse ridges on the dorsum, abdominal tip with 6 pairs of spines.
Life habits
In Shanghai and the Yangtze River basin, 1 generation per year; in Jiangxi, Taiwan, China, and other places, 2 generations per year; all overwinter as larvae in the stems and trunks of cotton, wood molds, peach trees, and various other trees. In Shanghai, pupation occurs in early to mid-June, emergence in mid to late June, and eggs are laid on cotton leaves. Newly hatched larvae bore into cotton petioles or fine branches to damage them; after the larvae grow slightly larger, they move to bore into thick branches or the main stem, disrupting the cotton's water supply; larvae damaging tea trees, mulberry, and fruit trees tunnel upward along the pith. In the 2-generation area of Jiangxi, pupation occurs from mid-April to late June, pupal stage 13-37 days, emergence from mid-May to mid-July. Adults hide by day and come out at night, are phototactic, mate and lay eggs shortly after emergence, eggs laid in masses in bark crevices and holes, oviposition period 1-4 days, eggs per female 224-1132, average adult lifespan 43 days, egg stage 9-15 days. Newly hatched larvae gather on the egg mass and feed on the egg shells; after 2-3 days they crawl to the upper part of branches and trunks, spin silk and drop down to disperse with the wind; the larvae bore in from the bud axil above the branch tip, and the part above it withers; after 5-7 days they move to damage thicker branches; when boring in, they first make a transverse ring girdle under the bark, so the upper part mostly dies, then tunnel upward within the xylem; after maturing, they bore outward to make an emergence hole and then build a pupal chamber in the tunnel to pupate; at emergence the head and thorax protrude from the emergence hole, and the pupal shell remains at the opening. The 1st generation adults occur in August-September, and the 2nd generation larvae overwinter after autumn in the tunnels of damaged branches. Natural enemies include braconid wasps and Fusarium moniliforme.
Control methods
(1) In cotton fields, in conjunction with controlling other pests, collect and treat or burn cotton stalks early to reduce overwintering larvae in the stems.
(2) When sawdust-like frass is found around damaged wood molds, fruit trees, and other host trees, promptly prune out and burn the infested branches to prevent adults from emerging and entering cotton fields to lay eggs.
(3) When cotton plants are damaged, split open the cotton stems and kill the larvae.
(4) When tea trees, mulberry, and fruit trees are damaged, promptly prune out the affected branches and burn them in a centralized manner or bury them deeply; after 1-2 years they can be brought under control.
(5) During the peak emergence period of adults, in conjunction with controlling other pests, spray 50% parathion emulsifiable concentrate 2000-fold dilution, or 10% bromine-malathion emulsifiable concentrate 1000-fold dilution, 20% pyrethroid-malathion emulsifiable concentrate 1500-fold dilution, 20% chlorpyrifos-malathion emulsifiable concentrate 2000-fold dilution, 2.5% Kung Fu emulsifiable concentrate 3000-fold dilution, 21% mie shabi emulsifiable concentrate 3000-4000-fold dilution, 30% Taoxiaoling emulsifiable concentrate 2500-fold dilution, 2.5% Tianwangxing emulsifiable concentrate 1500-fold dilution.
Click to get massive cotton cultivation techniques
Click to get massive grain and oil crop cultivation techniques