1. wheat aphid wheat aphid can harm a variety of gramineous crops and weeds. From the seedling stage to the milk maturity stage, wheat juice is sucked, resulting in serious yield reduction. Wheat aphids can also spread wheat yellow dwarf virus disease.
Wheat aphids can parthenogenesis all year round in warm regions. There are many kinds of aphids that harm wheat, but there are mainly three kinds: wheat binary aphid, wheat long pipe aphid and corn aphid. All three kinds of aphids suck the juice of leaves, stems and young ears as adults or nymphs, which affects the normal development of wheat. Aphis longituba and Aphis tritici overwinter in wheat fields or gramineous weeds all year round; Corn aphid overwinters on apple trees in winter, and breeds in early spring to harm wheat fields or gramineous weeds. In wheat seedling stage, wheat aphid is the most common, and it migrates to weeds immediately after filling. Because wheat aphids are afraid of light, they are generally distributed on the back of leaves. Aphids longituba is not afraid of light, generally distributed on the front of leaves, and often clustered on the ear after heading and filling. Corn aphid is also afraid of light and likes humidity, which is mostly concentrated in the lower part of the plant and the middle of the leaf sheath, endangering the stem.
Control methods: proper irrigation in winter and weeding in early spring to reduce the breeding base of wheat aphids in winter and spring; Protect and utilize natural enemies, implement intercropping planting of wheat rape and wheat green manure, increase the number of natural enemies, and induce natural enemies to transfer to wheat plants; In the green period, the fertilizer water should avoid the peak period of ladybug spawning and protect the eggs and larvae of ladybug; Strictly master pest control indicators and natural enemy utilization indicators to reduce the killing of natural enemies.
The key period to control wheat aphid is heading to filling stage. 2.5% deltamethrin EC 1500 times solution and 3% acetamiprid EC 1000 times solution can be used as plant spray, and the control effect can reach over 95%. 50% aphid fog wettable powder, the dosage per mu 10 ~ 12g, spraying 15 ~ 30kg of water, the control effect is over 90%, and it is basically harmless to natural enemies. Spraying urine washing mixture (the ratio of urea washing powder to water is 1: 1: 300 ~ 500) has a good effect on killing aphids. Pirimicarb has a special effect on aphids, has a good effect on preventing and controlling pesticide-resistant organophosphorus aphids, and also has a good effect on preventing and controlling leaf-backed wheat aphids. The application method is as follows: 4-8g of 50% wettable powder is used per mu, and 20-50kg of water is added to spray evenly, and the effective period is 7- 10 day. Safe and harmless to main natural enemies such as ladybugs and lacewings.
2. The main underground pests that do great harm to wheat are the golden needle worm, grub, mole cricket, cutworm and so on.
Prevention and control methods:
(1) Seed dressing control at sowing date: 0.4 kg of 48% chlorpyrifos-Tianda long-acting slow-release emulsifiable concentrate, or 0.5 kg of 20% toxin-phoxim emulsifiable concentrate, or 0.5 kg of 50% phoxim, and 250-500 kg of wheat seeds are mixed, buried for 3-4 hours for sowing, which can effectively control rodents and white grubs.
& ltimg class = " scroll loading " src = " http://47 . 94 . 224 . 236/Baidu/datianzowukonghaizengshoujishuwenda/ 109 1233730 1 0002 _ 38 _ 1② root irrigation: when pests are rampant at seedling stage, 2% avermectin is 3,000 times, 90% avermectin is irrigated 8 ~ 10 day/0 time, and it is irrigated for 2 ~ 3 times continuously, and the effect of killing ground tigers is over 90%, and white grubs can also be treated.
③ Poisoning soil: 0. 1 kg of 50% phoxim emulsifiable concentrate per mu, mixed with 25 ~ 30 kg of fine sand or fine soil and applied to the soil, can control various underground pests.
(4) Trapping and killing adults: setting black light to trap and kill adults in peak period; Mix 1 kg of 40% dimethoate EC or 90% trichlorfon with 100 kg of fried wheat bran or bean cake, each mu 1 ~ 1.5 kg.
3. Occurrence and control of wheat red spider, also known as wheat spider, fire dragon, red drought, wheat lice, etc. There are mainly two kinds of spiders: the long-legged wheat spider and the round wheat spider.
(1) Spiders in MaiQuan mostly occur in provinces south of 37 degrees north latitude, such as Shandong, Shanxi, Jiangsu, Anhui, Henan, Sichuan and Shaanxi. The long-legged spider of wheat mainly occurs in areas from the north of the Yellow River to the south of the Great Wall, such as Hebei, Shandong, Shanxi and Inner Mongolia.
(2) The morphological characteristics of spiders:
① Adult: Female adult eggs are round, with a body length of 0.6 ~ 0.98 mm and a body width of 0.43 ~ 0.65 mm, with a dark brown body, 8 cross sections on the back and a protruding anus. There are 4 pairs of feet, and 1 pair of feet is the longest.
② Eggs: Wheat-shaped, about 0.2 mm long and 0. 1 ~ 0. 14 mm wide, with dark red at first, then light red, and pentagonal net pattern on it.
(3) Larvae and nymph: There are 3 pairs of newly hatched young mites with the same length. The body, mouth and feet are reddish brown, and gradually turn dark green after feeding. After molting, the larvae enter the nymph stage, with four pairs of feet, and their body shape is roughly similar to that of adults.
Wheat long-legged spider:
① Adult: The female adult is gourd-shaped, dark brown, with a body length of 0.6 mm and a width of about 0.45 mm. There are no obvious fingerprint spots on the back of her body. The back hair is short, 13 pairs, spindle-shaped, with 4 pairs of feet, red or orange, all slender. 1 feet are particularly developed. The middle pad is claw-shaped with 2 rows of sticky hairs.
② Eggs: In summer, eggs are cylindrical, orange-red, with a diameter of 0. 18 mm. The surface of eggshells is covered with white wax, and the top is covered with white wax, which looks like a straw hat. There are radial stripes on the top of eggs. Non-overwintering ovoid, red, about 0. 15mm in diameter. It was bright red when it was hatched and turned dark brown after feeding. The nymph stage is 4 pairs long.
(3) Harm crops such as wheat, barley, peas, alfalfa and weeds.
(4) Harmful symptoms Wheat spiders harm wheat seedlings in spring and autumn, and both adults and nymphs can be harmed. The damaged wheat leaves appear yellow and white spots, the plants are short and stunted, and in severe cases, they dry up and die.
(5) Occurrence characteristics: The long-legged spider of wheat has 3-4 generations a year, and overwinters as adults and eggs. In March of the following year, overwintering adults began to move, eggs hatched one after another, and reached the peak of reproductive damage in April-May. In the middle and late May, adults lay eggs in large numbers for summer. 65438+ 10 In the first half of June, eggs hatched one after another, endangering wheat seedlings, and it took 24 to 26 days to complete the first generation. In 1, spiders in MaiQuan have 2 ~ 3 generations, overwintering with adults, nymphs and eggs on wheat plants and weeds. From mid-late March to early April, the insect population was large and harmful, and it subsided in late April. Over-summer eggs began to hatch in 10, endangering autumn seedlings. Each female can lay more than 20 eggs on average, and it takes 46 ~ 80 days to complete 1 generation. Both wheat spiders are mainly parthenogenetic.
Long-legged spiders like drought, and the optimum temperature for survival is 15 ~ 20℃, and the optimum relative humidity is below 50%. Spiders in MaiQuan are mostly active before eight or nine in the morning and after four or five in the afternoon. Not drought-tolerant, living temperature 8 ~ 15℃, humidity above 80%. In case of strong wind, it is mostly hidden in the lower part of wheat.
(6) Prevention and control methods ① Agricultural prevention and control: Take measures such as crop rotation, reasonable irrigation, shallow tillage and stubble removal after wheat harvest to reduce insect sources.
② Chemical control: 20ml/ mu of 2.0% Tiandamycin or 15% pyridaben EC; 15% saozumim EC 15 ~ 20ml/ mu, and 30 ~ 45kg water is sprayed randomly.
4. Occurrence and control of wheat midge, also known as wheat maggot, including wheat red midge and wheat yellow midge, is widely distributed in almost the whole wheat producing area. Their occurrence is related to wheat varieties, climatic conditions, farming systems, natural enemies and other factors, among which wheat varieties, climatic conditions and suitable control periods are the most closely related.
Morphological characteristics of (1) red midge;
① Adult: 2 ~ 2.5 mm in length, 5 mm in wingspan and orange-yellow. The male antenna has 14 knots, because each knot has 2 knots with the same length, and each knot has 1 loop length, which looks like 26 knots; The female holding device has teeth at the base, thin end, narrow abdominal flap, longer than dorsal flap, and shallow carving at the front end. Each node of the mother antenna has only 1 node, and the loop hair is very short. The ovipositor is not long, not more than half the length of the abdomen when stretched, and there are 2 petals at the end.
② Eggs: about 0.32 mm× 0.08 mm in size, ovoid, with no appendages at the end.
③ Larvae: 3 ~ 3.5 mm long, orange-yellow, with scaly protrusions on the body surface, Y-shaped xiphoid plate on the chest and abdomen surface, acute front end, and four protrusions at the end of the last segment.
④ Pupa: orange-red, with short 1 opposite hairs in front of the head.
Yellow midge:
① Adult: Similar to the red midge, the main difference is that the body color is bright yellow, and the male has no teeth at the base of the female organ; The female ovipositor is very long, extending as long as her body.
② Egg: The size is 0.25mm× 0.068mm, and there is a transparent band-shaped appendage at the end, which is about the same length as the egg.
(3) Larvae: 2 ~ 2.5 mm long, yellow-green, bright yellow after burial, smooth body surface, arc-shaped shallow crack at the front end of flag leaf, and two protrusions at the end of the last segment.
④ Pupa: the body is bright yellow, and the hair is long before the head 1 pair.
(2) Harm crops such as wheat, barley, rye and Pteris multifida.
(3) Harmful symptoms Both midges lurk in the glume as larvae, sucking the juice of the filling wheat grains, and producing shells and empty shells. A big year can cause the destruction of the whole field. No harvest of particles.
(4) Occurrence characteristics: The two midges basically produced 65,438+0 generations in 65,438+0 years, and the developing larvae cocooned in the soil for the winter. Before and after wheat jointing in the following spring, when there was enough rain, the overwintering larvae began to move to the surface. At the booting stage of wheat, larvae gradually pupate, while adults flourish at the booting stage of wheat and lay eggs on the ears of wheat.
(5) Control methods ① Agricultural control:
A. select insect-resistant varieties. Wheat varieties with compact panicle type, long and dense internal and external glumes, thick grain skin and difficult pulping should be selected.
B. crop rotation and stubble rotation. Rotation of wheat with rape, beans, cotton, garlic, onion and rice can reduce the harm.
② chemical control a. soil treatment:
Time: the first and last shallow tillage before wheat sowing; The second time was at the jointing stage of wheat; The third time was at the booting stage of wheat.
Pesticide: Use 48% Tianda chlorpyrifos slow-release emulsifiable concentrate or 20% toxin emulsifiable concentrate 150ml, add 5kg of water, spray it on 20-25kg of fine soil, mix well to make toxic soil for application, plow it while spreading, and turn it into the soil.
B. Chemical control in the adult stage: before wheat heading and flowering, 2.5% DAP is used to reach 2000 times of high-efficiency cypermethrin emulsifiable concentrate, or 2% DAP is used to reach 2000-3000 times of abamectin, or 48% DAP slow-release emulsifiable concentrate 1 000 times, or 40% DAP wettable powder/kloc-0.
5. Wheat sawflies, also known as Syngnathus, Myxomycetes and Myxomycetes, mainly include wheat sawflies and barley sawflies. Mainly distributed in the wheat area north of the Yangtze River.
(1) Morphological characteristics ① Adult: 8 ~ 9.8 mm in length, slightly smaller in male, black and bluish, with 1 white spots on both sides of the back chest. Wings are transparent and membranous.
② Eggs: kidney-shaped, flat, yellowish and smooth.
(3) Larvae: 5 instars in total, the mature larva is 8 mm, cylindrical, with thick chest and thin abdomen, with transverse folds in each section of the chest and abdomen.
④ Pupa: 9.8 mm long, slightly smaller in male, yellowish to brownish black. The abdomen is small and the end is forked.
Barley sawfly, basically similar to wheat sawfly, has only one adult, the middle chest is black, and the sides of the shield are reddish brown.
(2) Harm crops barley and wheat.
(3) Harmful symptoms Wheat sawflies harm wheat leaves with larvae, bite into notches inward from the edge of leaves, and eat all the leaves in severe cases.
(4) Occurrence regularity: The wheat sawfly occurs in the northern wheat area 1 year/generation, overwinters as a pupa in the soil at a depth of 20 cm, and begins to emerge after the temperature rises in March of the following year. Adults lay eggs in the tissues near the main veins of leaves with saw ovipositor, and lay eggs in strings. A protrusion with a length of 2 cm and a width of 1 cm appeared on the leaf surface. Each leaf lays eggs 1 ~ 2 or 6. The egg period is 10 day. Larvae suspended animation harms 1 ~ 2-year-old leaves. After 3 years of age, I am afraid of light, lying in wheat bushes during the day and doing harm after the evening. When the 4th instar larvae eat a lot and have a high population density, they can eat up all the wheat leaves, and generally enter the peak of damage in mid-April. In the first half of May, the mature larvae lay dormant in the ground until September and June, and molted and pupated in 65438+ 10 to overwinter. Wheat sawfly has high temperature in winter, sufficient soil moisture and high temperature and soil moisture in spring, which is suitable for its occurrence and serious harm. Sandy wheat fields are more seriously damaged than cohesive soil.
(5) Prevention and control methods ① Agricultural prevention and control: Deep ploughing before planting wheat can turn out the dormant larvae in the soil, so that they cannot pupate normally and die. In areas where conditions permit, paddy-upland rotation and rice-wheat stubble rotation can eliminate the harm.
② Chemical control: Use 2.5% Tianda beta-cypermethrin EC (20ml/mu) and add 30kg of water to spray it evenly above the ground, or spray 2% Tianda abamectin 3000 times in the morning and evening.
(3) Artificial capture and flapping: capture and flapping at night by using the suspended animation habit of wheat sawfly larvae.
6. Prevention and control of wheat armyworm, also known as oriental armyworm, commonly known as shaving worm, marching worm and five-color worm. It is distributed all over the country. There are more than 60 species of armyworm pests in China, and the common ones are armyworm Lloyd and white vein armyworm, which are mixed with armyworm in the south, but the number and harm are generally less than armyworm. Although it is distributed all over the north, it is rare.
(1) There are 89 species of plants in 34 families. The southern rice areas mainly harm late autumn rice and winter and spring wheat; In the north, it mainly harms wheat, corn, millet, sorghum and highland barley. It also harms gramineous weeds.
(2) Hazard characteristics: bite mesophyll when young, making the leaves form transparent strip stripes. After the age of 3, you bite the wheat leaf along the leaf edge and form a notch. In severe cases, if you eat wheat as a polished rod, it will break the ear or bite the twigs at the ear stage, resulting in a large number of grains falling. When it happens, the crops can be eaten up within 1 ~ 2 days, causing serious losses.
(3) Morphological characteristics: Adult body length 17 ~ 20mm, yellowish brown or grayish brown. There are two pale yellow circular spots on the central front edge of the front wing, 1 small white spots behind the outer circular spots, 1 small black spots on both sides of the small white spots, and 1 black twill at the top corner. Eggs are steamed bread-shaped, arranged in single rows into egg pieces. The larva is 6 years old, and its body color changes greatly, with 4 pairs of ventral feet. The head of the advanced larva has brown and black splashes along the molting line, and the back has various longitudinal stripes. The back center line is white and thin, with thin black lines on both sides, reddish-brown secondary back line, upper and lower gray-white stripes, yellow valve line and upper and lower white stripes. Pupa length 19 ~ 23mm, reddish brown.
(4) Occurrence regularity of armyworm, which is a typical migratory pest, migrates from south to north along the airflow from March to mid-August every year, and moves south with the northerly airflow from late August to September. In China, from south to north, 8 ~ 2 generations occur in turn every year. In the eastern half of China, 6-8 generations occur in the south of 27 degrees north latitude 1 year, with late rice generation in autumn and wheat generation in winter occurring more frequently; In the area of 27 ~ 33 degrees north latitude, 1 year occurs for 5 ~ 6 generations, and the late rice generation suffers more in autumn. In the area of 33 ~ 36 degrees north latitude, 1 year has 4 ~ 5 generations, especially in spring. In the area of 36 ~ 39 degrees north latitude,/kloc-0 has 3 ~ 4 generations per year, especially in autumn, which is harmful to wheat, corn, millet and rice. 2 ~ 3 generations occur in the north of 39 degrees north latitude 1 year, especially in summer, which harms wheat, millet, corn, sorghum and pasture. The monthly isotherm of 65438+ 10 is 0℃ (north of 33℃ north latitude), so it can't overwinter and moves in from the south every year. 65438+1October isotherm 0 ~ 8℃ (the northern half of 33 ~ 27 degrees north latitude) mostly overwinters as larvae or pupae in rice stubble, rice field ridge, straw pile, water chestnut, lotus root and weeds, while in the southern half, larvae overwinters in wheat weeds, but the number is small; The isothermal line of 65438+ 10 is 8℃ (south of about 27℃ north latitude), which can be propagated all year round, mainly endangering the winter in wheat fields.
(5) Prevention and control methods ① Agricultural prevention and control: select 8- 10 stalks with complete leaves and no mildew before the adult spawning peak, tie them into a small handful, 30-50 stalks per mu, and replace them every 5-7 days (if the stalks are soaked with chemicals, the number of stalk changing can be reduced), which can significantly reduce the density of insect population in the field. In the larval stage, ducks are allowed to peck.
② Physical control: It is very effective to trap and kill adults with frequency vibration insecticidal lamp.
③ Drug control: In the wheat field, in the larval stage (peak period of 2nd and 3rd instars), 25% triadimefon No.3 suspending agent is added for 2000 times, or 90% trichlorfon crystal, or 2.5% deltamethrin EC for 2000 times, or 25% dimehypo for 200-400 times, and water is added for 30-400 times.