Strawberry pests and diseases generally occur to a lesser extent in new production areas, and there are fewer types of diseases and insect pests, which do not pose a greater harm to production. However, in old production areas, the occurrence of pests and diseases is more complex and often poses a great threat to production. In some areas, there are years that can even cause devastating disasters to production. Therefore, strawberry growers should pay attention to and master the basic knowledge of strawberry pest control.
<h1 class="pgc-h-arrow-right">1． Agricultural control</h1>
The incidence of diseases and insects is mainly reduced through comprehensive measures such as the selection of disease-resistant varieties, the selection of detoxification seedlings, the selection of planting sites, reasonable rotation, intercropping, the use of high furrow (ridge) planting, the control of transmission and diffusion routes, the strengthening of plant management, the control of temperature and humidity, the cleaning of gardens and soil disinfection.
<h1 class="pgc-h-arrow-right">2． Physical control</h1>
(1) Booby traps
That is, the use of pests to avoid light, food, etc. to booby trap or drive away. If yellow paint is applied to 100 cm × 20 cm cardboard, coated with a layer of motor oil, and hung between the rows, it can trap aphids and whitefly. When the yellow plate is full of pests, it is coated with a layer of motor oil. This method can effectively control these two types of pests in the greenhouse, and hang 30 to 40 pieces of cardboard per 667 square meters. Pests such as twill moths and dancing poison moths can be booby-trapped by insecticidal lamps.
(2) Barrier
Insect-proof nets or silver-gray film strips are set up at the vents of the greenhouse, which have a blocking or repellent effect on aphids. Strawberry planting rows covered with milky white or silver-gray mulch film can repel aphids.
(3) A combination of hunting and booby-trapping
When pests first occur, manual hunting is an economical and effective control method, especially for individually large larvae in sheds. Digging a ditch in the planting area, putting horse manure and poisonous bait in the ditch can trap the scorpion, and can also use sweet and sour to trap pests such as nocturnal moths and ground tigers, and then manually concentrate on elimination. According to the ratio of wine, water, sugar and vinegar to 1:2:3:4, the formula is added to the appropriate amount of enemy insects, put in the basin, and replaced once a week.
(4) High temperature treatment
The strawberry seedlings were preheated in 35 °C water for 10 minutes, and then soaked in hot water at 45 °C for 10 minutes, cooled and planted, which can control strawberry bud nematodes.
<h1 class="pgc-h-arrow-right">3． Biocontrol</h1>
At present, it is mostly used for pest control. Its characteristics are not to pollute the environment, not easy to destroy the ecological balance, safe for people, livestock and cultivated crops, pests will not produce resistance, and the control effect is good. The protection and use of natural enemies to control pests has become the focus of biocontrol research at home and abroad. Natural enemies of pests are divided into predatory natural enemies and parasitic natural enemies, and the former are many types and widely distributed. The common insect predators in China are: ladybirds, grass maggots, spiders, aphid-eating flies, red-eyed bees, melanoma bees, aphid cocoon bees, aphid bees, aphid hunting insects, predatory mites, praying mantises and insectivore birds. They must be protected and used in the process of production and life.
<h1 class="pgc-h-arrow-right">4． chemical control</h1>
The use of pharmaceutical control technology to recover the losses caused by diseases and insect pests in crops has the characteristics of fast speed and high efficiency, and is the most commonly used method for fruit growers. With the continuous research and development of new pesticide products, pharmaceutical prevention and control technology is constantly developing and improving. The use of highly toxic and high residue pesticides is prohibited in the prevention and control of pharmaceutical agents, and all pesticides used should be registered with the Ministry of Agriculture.
The smoking method is preferred in the protected areas. Advocate the use of biologically derived pesticides, which come from naturally occurring organisms and their metabolites, and have the advantages of strong selectivity, non-pollution of the environment, safety to people, animals and crops, no harm to natural enemies, and not easy to produce resistance. There are many varieties of such pesticides, such as antibiotic pesticides avermectin, Thuringiensis and so on. Low toxicity, low residue chemical pesticides can also be used, such as imidacloprid, dimethod, gram mite, daisen manganese zinc, methyltobuzin, carbendazim, nova, perchlorvine, bacitracine, thiamethione and so on. Mineral-derived pesticides such as stone sulfur compounds, Bordeaux liquids, etc. can also be used. There should be limited use of moderately toxic pesticides, such as dichlorvos, aphid resistance, chlorpyrifos, high-efficiency cypermethrin, etc.
<h1 class="pgc-h-arrow-right">5． Strawberry common disease control</h1>
(1) Strawberry gray mold
Strawberry gray mold is one of the main diseases that occur in Strawberry producing areas in China, and it is also one of the most dangerous diseases. Rotten fruit caused by gray mold can generally reduce production by 1 to 30%, and the weight can reach more than 50%. Gray mold disease generally infects small fruits after flowering and fruit setting, on the side close to the ground, and then spreads to the entire tidbit, making the whole tidal dry and decaying. After the petiole and fruit stalk are infected, they first turn brown, and finally wither and dry up. Fruit susceptibility mostly starts from the sepals of the fruit base stem, and at the beginning of the disease, there are small water-stained brown spots, and then the spots expand, so that the whole fruit tissue becomes soft and rotten, and a layer of gray mold grows on the surface of the fruit, and finally the mold layer is covered with the surface of the fruit into rat gray. The pathogen of the disease overwinters in the tissues of the victim plants, forming spores in a high humidity environment with a temperature of about 20 °C, and the spores spread freely. However, at high temperatures above 31 °C and low temperatures below 2 °C and dryness, spores are not formed and no disease occurs. In particular, when baojiao early growth, Dana and other disease-susceptible varieties, when cultivated in the open field, nitrogen fertilizer is more, and the humidity after flowering is large, and the harm is heavy; when the semi-promotion cultivation is concentrated, when the fertilizer, dense planting, and the lower leaves are too luxuriant, if there is even rain, the onset of the disease is fast.
Control methods: (1) Control the amount of fertilization, planting density and field humidity. (2) Mulching after treating diseased leaf remnants before overwintering is the key to suppressing the source of overwintering bacteria and reducing the occurrence of diseases. Mulching has a barrier effect, preventing fruit from coming into contact with the soil, removing old, residual leaves and disease-inducing inflorescences in time to remove diseased fruits. (3) Pay attention to the selection of stubble and implement crop rotation. (4) Deep ploughing before colonization, and advocating the cultivation of high furrows and high ridges. (5) Medicament treatment of soil. Sprinkle 5% carbendazim wettable powder 75 to 90 kg per hectare before colonization, and then rake into the soil, which has a good disease prevention effect. Protected cultivation with 45% bacterium smoke excipient 200 ~ 250 g / 667 m2 sterilization; gray mold disease at the beginning of the onset of 50% parahexine wettable powder 1000 ~ 1500 times liquid spray, and then according to the incidence of the drug, the interval of 7 to 10 days, the agent should be rotated. It can also be used with Shigao 1000 to 1500 times liquid, or 40% gray mold gram 1000 times liquid, or 65% Daisen zinc wettable powder 500 times liquid. Note: Chlorphenoxyphenirone should not be mixed with other agents, nor should it be used alternately with sokyline and nongriline; spray an equal amount of Bordeaux liquid 200 times liquid, or polyoxychloride wettable powder 500 times liquid, dinoflorimide wettable powder 700 to 1000 times liquid, bacteriostatic ligability powder 500 to 800 times liquid, dichlorinolin wettable powder 600 times liquid, etc., once every 10 days, until the end of a large number of fruit harvest.
(2) Strawberry powdery mildew
Strawberry powdery mildew is a serious disease in cold and cool areas, mountain cultivation and protected area cultivation. In some years in the strawberry-producing areas in northern China, the incidence is more serious, and even the flood is a disaster, and the loss is serious. Strawberry powdery mildew is mainly harmful to leaves and young tips, and flowers, fruits, stems and petioles can also be affected. Pathogenic mycelium grows on both sides of the leaf, petiole, tender tip and fruit, and the ascomycetes are brown and scattered or slightly clustered on the leaves. At the beginning of the onset of the leaf disease, a thin layer of white hyphae grows on the leaf surface, and as the disease worsens, the leaf margin gradually rolls up to form a spoon,The dark stains and white powders of different sizes occur on the leaves, and in the later stage, it shows reddish-brown spots, the leaf margins shrink and scorch, and the young fruits cannot expand normally after the buds are affected. If the fruit is affected at a later stage, the fruit surface is covered with a layer of white powder, which loses luster and hardens, and the coloring is slow and loses the value of the commodity. In the northern region, the pathogen remains on the ground with the disease residue or overwinters on the old leaves of strawberries, while in the south, it winters or overwinters on the host, becoming the source of infection early the following year. Strawberry powdery mildew is a specialized parasitic bacterium that mainly relies on propagating materials such as diseased strawberry seedlings for medium- and long-distance transmission. Hyphae epiphysis on the leaf surface, from germination to invasion generally takes more than 20 hours, can grow 3 to 5 hyphae per day, 5 days later in the infestation of the formation of white filamentous plexus lesions. After 7 days of maturation, conidia are formed and spread loosely, and re-infect. The conidia produced are at a temperature of about 20 °C, and spread rapidly in the range of 15 to 25 °C.
Prevention and control methods: (1) Clean up the garden in winter and spring and burn rotten leaves. Remove diseased old leaves in time during the growing season. Strengthen the management of fertilizer and water, planting should not be too dense, so that the plant ventilation and light, growth is robust. (2) Spray 2% agricultural resistance 120 or 2% Wuyi mushroom water agent 200 times liquid, and spray it again every 6 to 7 days. Or use 27% high-fat film emulsion 80 to 100 times liquid, start spraying at the beginning of the disease, 5 to 6 days once, spray 3 to 4 times. Or sprayed with 25% triazolone wettable powder 2000 times liquid, or polyoxymycin wettable powder 1000 times liquid, ammonium copper emulsion 500 to 1000 times liquid, or 30% Tefrin wettable powder 2000 times liquid, or 40% polysulfide suspension 500 to 600 times liquid, or methyl tolbuzin 1000 times liquid. (3) Greenhouse cultivation can be sterilized with 45% bacterium smoke fumigation 200 to 250 grams or soxkeling smoker per 667 square meters.
(3) Strawberry snake eye disease
Also known as leukoplakia, it occurs everywhere. It is mainly harmful to the old leaves of strawberries, but also affects petioles, creeping stems, fruit stems, fruits and seeds. Small purple-red spots begin to form on the diseased leaves, which then expand into a round spot of 2.5 mm in size, with purple-red edges and gray-white centers that resemble snake eyes. Too many spots can cause leaf browning. When the germ invades the seeds on the berries, the edges of the affected seeds and the surrounding flesh turn black and lose their commodity value. The pathogen overwinters with hyphae or conidia on the plaque, and after overwintering, conidia or ascospores are produced in the following spring for transmission and initial infection. Sclerotia on the seedlings and topsoil are the main vectors of transmission. The suitable temperature for the propagation of pathogens is 8 to 22 °C, and if it is lower than 7 °C or higher than 23 °C, it is stunted. Lack of light in autumn and spring, heavy onset in wet weather, and severe on stubble fields, extensively managed and poorly drained plots.
Prevention and control methods: (1) susceptible varieties should control the use of nitrogen fertilizer to prevent the growth of the seed; (2) pay attention to cleaning the garden in winter and spring, remove the residue of rotten and diseased leaves in time, burn or bury deeply, and remove the diseased seedlings during colonization; (3) spray 500 times the wettable powder of copper (DT) with succyl fertilizer at the beginning of the disease, or 400 times the liquid of 30% green preservation suspension, or 300 times the liquid of 14% copper ammonia, or 77% of the wettable powder that can be killed 500 times liquid, or 75% of the wettable powder of 75% bacillus qing wettable powder, or 70% Daisen manganese zinc wettable powder 350 times liquid, once in 10 days, a total of 2 to 3 times.
(4) Strawberry Phytophthycosis fruit rot
It mainly infects strawberry fruits, but can also occur on roots, flowers and leaves. After the strawberry fruit is diseased, some of the seeds first turn black, the fruit surface loses luster, and gray-brown water-stained spots appear. In severe cases, a layer of white mold grows on the lesions, and the flesh of the fruit becomes gray-brown and rotten, and has an unpleasant fishy odor, and when it is dry, the diseased fruit shrinks into a brown zombie fruit. Once phytophthora occurs, it is difficult to control with agents. The pathogen is a disease of soil fax bacteria, and the oospores overwinter in the residues and soils such as diseased fruits and roots, and the pathogens have strong cold resistance. Pathogenic spores are transmitted by wind and rain, running water, agricultural tools, etc. The optimal temperature for spore generation is 21 °C, the optimal temperature for spore infestation is 17 to 25 °C, the temperature for spore growth is 10 to 30 °C, and the optimal temperature is 25 °C. After each rain, there will be a peak of incidence, which shows that high humidity and strong light are important conditions for the onset of the disease, with more rainfall and high incidence. Soil is heavy, low-lying, partial nitrogen fertilizer and continuous cropping are heavily affected.
Prevention and control methods: (1) pay attention to prevention, because phytophthora is mainly spread with water, irrigation in the ripening period of strawberries, it is necessary to strictly prohibit flood irrigation with large water to prevent water from entering the fruit; conditional areas, such as in the production of protected areas, take measures of high furrow and low irrigation, which can basically eliminate the occurrence of the disease; (2) pharmaceutical prevention and control, can be sprayed with 60% disinfectant alum wettable powder 500 times liquid. Or spray 500 times of manganese zinc, bacillus or chlorpyrifos before the onset of the disease and remove the zombie fruit in the field. At the beginning of the disease, 25% carbendazim 300 times liquid, or 25% methocerin wettable powder 1000 to 1500 times liquid can be sprayed.
(5) Strawberry anthrax
Anthrax is mainly harmful to leaves, petioles and creeping stems, but also to petals, sepals and berries. The symptoms of victimization can be roughly divided into two types: local spots and whole plant wilting. The symptom is the production of 3 to 7 mm long spots on the creeping stem and petiole, initially reddish-brown, then black ulcerated, slightly concave, spindle-shaped or oval-shaped. When the spots surround the creeping stem or petiole in a full circle, the area above the spots dies. When wilted plants first emerge, brownish-red spots appear on the edges of the diseased leaves, or turn brown or black. When the onset is mild, the leaves wilt during the day and recover in the evening. When the disease is severe, it dies within a few days. After the berry is damaged, it produces nearly round brown spots, soft rot and depression, and can also grow fleshy red sticky spore mass in the later stage. Pathogenic bacteria overwinter in the remnants of diseased tissue, and the following year the bud stage begins to infect the young parts near the ground. Strawberry anthrax grows at a moderate temperature of about 30 °C, which is a typical high-temperature pathogen. The disease occurs in the rainy season when the temperature is 25 to 30 °C, and the onset of the disease is generally from mid-July to the end of September, and the onset time of the year with high incidence can be extended to October. In the field, conidia are transmitted by wind and rain, and excessive nitrogen fertilizer, plant closure and continuous cropping are severely diseased.
Control methods: (1) planting should not be too dense, nitrogen fertilizer should not be excessive, apply sufficient organic fertilizer and phosphorus and potassium fertilizer to improve plant disease resistance; (2) timely removal of disease residues; (3) with chlorpyridoxine, dinomycin or 50% carbendazim 600 times liquid, or 2% agricultural resistance 120 water agent 200 times liquid, or 40% 1000 times liquid, or 25% Amicida suspension spray control.
(6) Strawberry red middle pillar root rot
Also known as red heart disease or brown heart disease, it is the main disease of strawberries in cold and moist areas, and the incidence of disease is more severe in water and drought rotation fields and old production areas. In China's Liaoning, Hebei and other places where strawberries are old, it has become a devastating disease in production. It is mainly harmful to the roots, and when the disease begins, it decays at the tip of the young root. When there is a crack in the root, the central pillar of the root is red and decayed, and can be extended to the rhizome, and the diseased plant is easily uprooted. The disease can be divided into acute atrophy type and chronic atrophy type. The acute type mostly invades the roots in spring and summer, from after colonization to the growth of early spring plants, there is no abnormality in appearance, but from mid-March to May, especially after a long rain and early sunshine, the leaf tip suddenly withers, and soon appears green, causing the whole plant to die rapidly; the chronic type mainly occurs during the colonization to the early winter, the old leaf edge or the whole leaf becomes purple-red, the leaves gradually wither, the plant shrinks, gradually withers and even withers, and the central column of the root becomes reddish-brown rot. Pathogens are a fungus that infects only strawberries and survives in the soil as oospores, which are transmitted by diseased strains, soil, water and farm tools. When the conditions are right, conidia are produced for infestation and re-infection, invading the epidermis at the tip of the root, and the hyphae grow along the middle column, and then the middle column turns red and decays. When the soil temperature is low and the humidity is high, it is easy to get sick, the ground temperature is 6 ~ 10 °C is the appropriate temperature, and the ground temperature is higher than 25 °C. In general, spring and autumn are prone to disease in rainy years, and the incidence of low-lying wet soils is more serious.
Prevention and control methods: (1) Regardless of the disease area or the disease-free area is not suitable for a single continuous planting of strawberries, should be implemented rotation of stubble; the use of high furrow or ridge cultivation, covering the mulch film, is conducive to improving the ground temperature to reduce the incidence of disease; timely drainage after rain, it is strictly forbidden to flood irrigation; (2) the use of lime nitrogen soil fumigation, burrowing or drip irrigation for soil disinfection; also after strawberry harvesting, the strawberry plants in the field are all dug up, a large amount of organic fertilizer is applied, the soil is turned deeply, and the ground is covered with transparent plastic film for 20 to 30 days in the hot and high temperature season after irrigation. The use of solar energy to raise the ground temperature and play a role in soil disinfection; (3) soak the seedlings with 50% manganese zinc ethyl aluminum wettable powder before colonization; (4) dig up the diseased plant in time, and water 58% methammer linganese zinc wettable powder, or 60% antiseptic alum wettable powder 500 times liquid, or 72% frost urea manganese zinc wettable powder 800 times liquid, etc., continuous prevention and control 2 to 3 times.
(7) Strawberry blight
Strawberry blight is mainly onset during the flowering and fruiting stage, and the petiole appears black-brown striped spots at the beginning of the disease, and in severe cases, the leaves droop, the plant dwarfs, and finally wilts and dies. The developmental temperature of the pathogen is 28 °C, the lowest is 8 ~ 12 ° C, and the highest is 36 ° C, which is a high-temperature resistant pathogen. At the beginning of the disease, only the heart leaves turn yellow-green or yellow, some curl or wave shape to produce deformed leaves, the leaves of the infected plant lose luster, the growth is weak, and there are often 1 to 2 deformed or narrow sclerosis in 3 leaflets, mostly on one side. The old leaves are purple-red and wilted, the later leaves are yellowish, and finally the whole plant wilts. The symptoms of the diseased plants that are lightly affected sometimes disappear, and the root crown, petiole, and peduncle vascular bundles of the affected plants turn brown to black brown, and the results are reduced, and the fruit cannot expand normally and the quality becomes inferior. Wilt is similar to Verticillium wilt, but the wilted heart leaf is yellowed and curled into deformities, mainly occurring in high temperature periods, unlike Verticillium wilt. The disease is transmitted through diseased strains and soils, mainly by overwintering in the soil where mycelium is left with the disease residue or on unripe fungal fertilizers and seeds. Spores can survive in the soil for 5 to 10 years, and generally have the highest density in the 20 cm soil layer. Pathogens that survive in the soil and fertilizer become the main source of initial infection the following year. Pathogens spread when the diseased plant is divided, when the strawberries are transplanted, the spores sprout, the pathogen invades from the root from the fissure or wound, multiplies, grows and develops in the rhizome vascular bundle, moves and multiplies in the catheter, and destroys the normal transport function of the plant by blocking the vascular bundle and secreting toxins, causing wilting. The onset of the disease begins at 15 to 18 °C, and is most appropriate at 28 to 32 °C. Continuous cropping or clayous soil and poor drainage can aggravate the disease.
Control methods: (1) quarantine seedlings, establish virus-free nurseries, branch seedlings from disease-free fields, plant disease-free seedlings; find that diseased plants are pulled out in time and burned centrally; (2) rotate crops, with rice and other aquatic crops, the effect is better; (3) heavy stubble fields are disinfected with chlorinated bitter eye fumigation before colonization, covered with plastic film after application, and planted after 7 days; seedlings are soaked with 50% methyl tolbuzin wettable powder for 5 minutes before colonization, advocating composting of enzyme fungus; (4) 50% during the growth period Carbendazim wettable powder 600 times liquid, or 50% daisen manganese zinc 500 times liquid, or 50% benomylin wettable powder 500 times liquid spray the base of the stem, about 15 days once a time.
(8) Strawberry virus disease
Viral diseases are important diseases in strawberry production. Due to the harm of viral diseases, the production is generally reduced by 20% to 30%, and the serious one can reach 50%. There are four main types of strawberry virus diseases in China: strawberry mottled virus (SmoV), strawberry mild yellow-edged virus (SMYEV), strawberry veined virus (SVBV) and strawberry wrinkle virus (SCrV). Strawberry virus disease is not only diverse, but other plant viruses such as raspberry ring spot virus, tobacco necrosis virus, tomato black ring spot virus and chrysanthemum yellow-edged bacterioplast can also infect strawberries. The longer the strawberry is cultivated, the more types of viruses it infects, and the more serious the incidence of disease.
Strawberries are infected with a single virus, and plants without obvious symptoms are called latent viruses, such as the above 4 viruses. Its symptoms are only weak growth potential, dwarfing of the population, few results, small fruit types, low yields, reduced sugar content, and poor reproductive ability. However, there are also obvious symptoms of viral diseases, such as green petal virus disease in strawberry-producing areas abroad, the main symptom is that the petals turn green, and several petals are often planted together, the green petals turn red in the later stage, the berries are thin and pointed, the leaf edges become yellow, and the plant is severely dwarfed and clustered. The virus can be transmitted through soybean silkworms and is harmful to plants such as clover. When the virus disease is compounded, due to different sources of viruses, the symptoms are different, generally manifested as severe dwarfing of the plant, green loss of leaves, distortion and deformation, disease spots on the leaves or petioles, dull color of berries, and a large number of dead seedlings at the initial fruit stage. Strawberry virus disease is generally more pronounced in spring and autumn and more insidious in summer.
The four common viruses in China mainly overwinter on strawberry seedlings, and can be transmitted by mediators such as seedlings, aphids, leafhoppers, Tsubaki elephants and mites. Tomato black ringworm virus and raspberry yellow dwarf virus can infect strawberry plants through soil, and tobacco necrosis virus can be transmitted by The presence of Poty brassica rotis in the soil. Strawberries are quickly spread throughout the plant after being infected by the virus and are transmitted to the sub-plant through creeping stems.
Prevention and control methods: The most fundamental measure to prevent and control strawberry virus disease is to plant virus-free seedlings, which can be propagated by the stem tip tissue culture method described in chapter 1, establish a virus-free seedling breeding system, and implement a strict isolation and quarantine system. Other effective control methods include: strengthening field inspections, burning the diseased plants immediately, and timely control of aphids, mites and various vectors that can transmit viral diseases. Regularly renew strawberries, once a year in areas with high virus infestation rates, renew virus-free seedlings once a year; avoid intercropping or rotation of strawberries and solanaceous crops that are susceptible to viruses; and select virus-resistant varieties.
<h1 class="pgc-h-arrow-right">6． Strawberry common pest control</h1>
(1) Small land tiger
On strawberries, the young hearts, young petioles, young leaves and young inflorescences and mature berries are mainly infested with larvae. Mature larvae have a head width of 3 to 3.5 mm, a body length of 41 to 52 mm, and a body width of 5 to 6 mm, nearly cylindrical. The body is greenish brown, dark brown to dark brown, and the body surface is rough and covered with black granular spots. Small land tigers occur in 2 to 7 generations a year, and the first generation is generally seriously harmful. Adults (nocturnal moths) are long-distance migratory, prefer diurnal nocturnal emergence, have a strong tendency towards sweet and sour liquid and black light, and lay eggs on the soil blocks on the roots of the leaf dorsals of weeds and crop seedlings.
Control methods: (1) combine hoeing grass for artificial hunting; (2) protect and use natural enemies such as toads, frogs, spiders; (3) use 80% dichlorvos or 50% to kill ticks per hectare, 4500 to 8750 grams of fine sand soil 22.5 to 33.75 kg to make poisonous soil and sprinkle it between plants in the evening; or use 90% crystal enemy insects 50 grams to water 1 to 1.5 liters, stir-fried wheat bran or cake grits 2.5 to 3 kg, you can also mix chopped fresh grass 10 kg to spread, pay attention not to touch the fruit. During growth, 50% chlorpyrifos or 90% crystalline dichlorvos can also be used to irrigate ridges and roots with 800 to 1000 times liquid.
(2) Caddisflies
It is a multi-feeding pest that prefers to eat a variety of plants. Both adults and nymphs often bite the rhizome or bite the roots in the soil, causing the plant to wither and lose water and die. Sometimes the fruit is also eaten, causing the fruit to lose its commodity value. As the slugs travel through the surface to form many tunnels, the roots of the seedlings are separated from the soil and die of water loss and dryness. In Shaanxi, Shandong, Liaoning, Hebei and other places, 1 generation occurs in 2 years. It overwinters underground as adults or nymphs at depths below the permafrost and above the water table. From late March to early April of the following year, it moves upwards as the temperature rises, and in early to mid-April, it enters the topsoil layer and forms many tunnels for activities and feeding, and May to June is the peak period. Late June to early August is the spawning period for the moths to cross the summer, and after early September, a large number of nymphs and newly feathered adults rise from 14 cm underground to the surface, forming an autumn peak. After mid-October, as the temperature turns cold, it will gradually enter the soil for wintering. It has phototropism and tendency towards wheat bran, and is mostly harmful to low wetland activities.
Prevention and control methods: 30 ml of 30 ml of 30% dimethoate can be used, mixed with 1 kg of stir-fried wheat bran or bean cake, sprinkled on the surface in the evening, generally every 667 square meters with poisonous bait 1.2 to 2 kg can effectively kill the caddisflies. Or treat with methamidophos and parathion with water.
(3) Grubs
Grub is a general term for the larvae of the coleoptera golden turtle beetle family. They occur universally, are widely distributed, are harmful, and have a very mixed diet. The larvae tend to gather in the soil in winter, and prefer to eat root seedlings, resulting in a lack of seedlings and ridge breakage. Grub grubs are hypertrophied, curved like a "C", 3 to 4 cm long, white or milky white, soft and wrinkled body walls, and sparse hairs on the surface of the body. The head is large and round, yellowish brown or reddish brown, with left and right symmetrical bristles, 3 pairs of pectoral feet, long hind feet, 10 segments on the abdomen, and spiny hairs on the buttocks. Grubs generally have 1 generation per year, or 1 generation in 2 to 3 years, and 1 generation in 5 to 6 years for the elderly. Grubs inhabit the soil all their lives, and their activities are mainly related to the physical and chemical characteristics of the soil and the temperature and humidity. The most suitable soil temperature in a year is on average 13 to 18 °C, higher than 23 °C, gradually shifting downwards, and then transferring to the upper layer when the soil temperature drops in autumn, so in the spring and autumn, grubs are the most harmful. Adults like to lay eggs in manure, which occurs severely with manure, especially when using unripe chicken manure.
Control methods: (1) ploughing the land in spring and autumn, people pick birds to kill the grubs; (2) avoid the application of uncorried manure to reduce adult spawning; (3) before planting, use chlorpyrifos soil treatment agent 4 kg /667 m2, applied to the soil. During the growth period, 100 times the liquid of 50% poison tick can be used, and it is slowly poured into it with watering, and the control effect is remarkable, and it can also treat both slugs and golden needle worms.
(4) Whitefly
It is an important pest cultivated in greenhouses and greenhouses. Adults are 1 to 1.5 mm long, have two pairs of wings, and are covered with white wax powder. The insect occurs for more than 10 generations a year, and cannot survive outdoors in winter, and overwinters in greenhouses in various insect states. Adults can lay eggs 1 to 3 days after feathering. The suitable temperature for breeding is 18 ~ 21 °C.
Whitefly hosts a wide range of plants, including alfalfa, phaseolus beans, cucumbers, eggplants, blackberries, grapes, peas, peppers, tomatoes and many ornamental plants. Its adults and nymphs cluster on the back of the leaves, sucking up sap, so that the leaf growth is blocked, and the plant cannot grow and develop normally. The worm can secrete a large amount of honeydew, which accumulates on the leaf surface and fruit, resulting in a large number of mold growth, seriously affecting leaf photosynthesis and respiration, causing leaf wilting, and even the death of the whole plant, and the loss of commodity value of the product. Adults prefer to lay eggs on the back of the top young leaves, and females can also reproduce as parthenogenes, but their offspring are all males and reproduce quickly. Whitefly have a strong tendency towards yellow.
Control methods: (1) use yellow plates to trap adult insects; (2) remove the residues and weeds of the former stubble crops, and use dimethoprim smoke fumigation control for greenhouses and greenhouses; (3) spray 25% thiazide ketamine (chlorpyrifolidine) wettable powder 1500 to 2500 times liquid spray at the beginning of the occurrence, with a safe interval of 11 days; in the whitefly bloom period, use 20% antiscametic emulsion 2000 times liquid or 2.5% high-efficiency cypermethrin 4000 times liquid spray.
(5) Aphids
Aphids occur in many forms of strawberry cultivation, especially in protected areas. With early summer and early autumn the density is greatest after snapping the shed. Aphids mostly feed on the petiole, leaf back, petiole base, seedling heart and other parts. There are many kinds of aphids, the most important of which are cotton aphids and peach aphids. Cotton aphids are transfer host types, eggs overwinter on peppercorns, summer dry grass, plantain and hibiscus and other plants, the following spring after the weather warms up after breeding as a pest, the peak period of harm mostly occurs in the summer and autumn of drought and little rain. Peach aphids are the main pest of cruciferous vegetables and have a very heterogeneous diet, with more than 350 species of host plants. Wintering in the rhizosphere soil of strawberries, vegetables, rapeseed and other crops. Aphids are similar in morphology , with a body length of 1 to 2 mm , light green , black thorax , and russet brown compound eyes. When harming strawberries, they mostly live in groups such as the heart leaf, petiole, and leaf back. The sap of strawberry plants is aspirated by the suction mouthpiece, and faded green spots are formed at the suction site, the leaves are curled, twisted and deformed, and the plant growth is weak, but the greater harm is the spread of strawberry virus disease. Aphids have strong fecundity, which can occur for more than 10 to 30 generations a year, and can multiply and pest plants all year round in South China. Wintering eggs produce winged aphids in the spring of the following year, migrate to various hosts, and then breed individuals in the way of viviparity, expand their harm, and after the autumn cool, some winged aphids migrate to the winter host to lay eggs for overwintering. Aphids can occur all year round on strawberry plants, with the highest density in early summer and early autumn, producing honeydew when sucking sap, and ants feed on honeydew, so when there are many ants near the plant, it indicates that there are aphids. Aphids tend to yellow and silver-gray, and this property is often used in production as a method of control of aphids.
Control methods: (1) the use of yellow plate traps to kill adult insects, hanging silver-gray strips at the entrance of the shed can repel aphids; (2) after flowering, it can be fumigated with 22% dichlorvos, 500 grams per 667 square meters, scattered in 7 to 8 places, lit at night, closed shed; also can be lit and fumigated at night. However, during the strawberry flowering period, in order to prevent and control the harm, the amount of aphid tobacco control agent used is reduced by 1/3 compared with the recommended dosage of vegetables. For example, after stocking bees fumigation, they should be maintained for more than 10 days before the bees can be put back into the greenhouse; (3) before the insulation of the shed is overwintered and covered with mulch film, the semi-scalloped strawberries should be sprayed once on the basis of removing old leaves, 1% matrine alcohol 800 to 1000 times liquid, or 10% imidacloprid 3000 times liquid, or 50% anti-aphid wettable powder 2000 times liquid.
(6) Leaf mites
Commonly known as the red spider. The main mites that harm strawberries are dimaculated leaf mites, cinnabar leaf mites and lateral multi-eating tarsal mites. Mites are small, less than 1 mm long, and only a small red dot can be seen with the naked eye. Mites are sucking mouthparts that like to suck sap from unexplored young leaves or on the back of leaves. Mites can breed for 10 to 20 generations a year, and can reproduce annually under the conditions of greenhouses and plastic greenhouses, which is very harmful to strawberries. The infested parts of the leaf mites initially appeared small white dots, and in severe cases, the leaves were rust-colored, like fire roasting, the leaves were wrinkled and curled and yellow, the plants shrank, and the new leaves stopped growing, which seriously affected the yield. Leaf mites can overwinter in various insect forms in weeds or in bark crevices. In early spring, when the temperature is above 10 °C, spawning and reproduction begin. In high temperature and dry weather, the reproduction is extremely fast, and the damage is more severe from June to September. Adult mites have no wings and spread by wind, rain, seedlings, tools and humans. Red spiders on various host plants can be transferred to each other.
Control methods: (1) eliminate the source of overwintering insects and remove overwintering host weeds; (2) spray 20% trichlorocarboxidol emulsion 1000 to 1500 times liquid, or 5% Nissolum emulsion, or 73% g mite emulsion 2000 times liquid, or 10% Uranus 2000 to 2500 times liquid, or 15% pyridium emulsion 2000 times liquid, or colloidal sulfur 200 times liquid, or 0.2 to 0.3 baumedo stone sulfur compound and other sprays. Stop taking the drug half a month before harvesting, and pay attention to changing the pesticide variety frequently to prevent resistance.
(7) Snails
Snails are molluscs that grind the stems, leaves, or roots of plants by means of small teeth on the filed tissues on the tongue and the bands on both sides of the tongue. Adult snail shells are 30 to 36 mm long, and the feet are on the ventral surface of the body, which is suitable for crawling. The juvenile shellfish layer is mostly below 4 layers. The ovoid is spherical, about 2 mm in diameter, initially white, and turns grayish-yellow and shiny before hatching. In late November, adult and young shells overwinter under objects in fields, earth crevices, dead branches and leaves, and behind houses, and begin in early to mid-March of the following year. Activities in the greenhouse and plastic shed begin in mid-to-late February. Snails lurk during the day, feed in the evening and early morning, and roost on the plant all day in the rainy day, in addition to favoring strawberry leaves, they can also harm near-ripe fruits. From late April to early to mid-May, the eggs are laid in piles in wet soil at the roots of the plant, and the eggs stick together into lumps. Hatching young beetles are clustered and dispersed as they grow up. Snails occur early in the strawberry field of the shed, prefer to inhabit dense plants and low-lying wet places, warm and humid weather and wet plots in the field are heavily damaged; under high temperature and dry conditions, snails often seal the shell mouth, lurk in the wet soil cracks, and when the conditions are suitable, they come out after rain or irrigation, and prefer to go out to eat in the evening or morning. Wintering begins again in mid-to-late November.
Prevention and control methods: (1) artificial capture and concentrated killing in the early morning or rainy day; (2) sprinkle with tea cake powder or tea cake powder 1 to 1.5 kg with water and 100 kg after soaking for 24 hours, its filtrate spray can also be used 50% chlorpyrifos emulsion 1000 times liquid spray; (3) use snail enemies to mix soybean cake powder or corn flour containing 2.5% to 6% active ingredients, or use 8% snail spirit granules 1.5 to 2 kg, crush and mix fine soil or cake crumbs 5 to 7.5 kg, when the weather is warm and the soil surface is dry. In the evening, it is sprinkled between the rows near the roots of the affected plant, and after 2 to 3 days, snails exposed to the drug will secrete a large amount of mucus and die. The appropriate period for prevention and treatment is before the snails lay eggs in March to mid-April, and it is better to prevent small snails from June to July.
(8) Small house ants
After the strawberry is ripe, the ants can nibble on the flesh, first 1 to 2 bites, and then pass the information to other ants, the ant colony moves, the reincarnation of feeding, gradually from a small pit to a large pit, and finally eat the fruit, leaving only the calyx. Ripe fruit is sometimes affected by 30% and the loss is severe. In Yangling, Shaanxi and other places, it was also found that the ants in the greenhouse still ate pollen during the flowering period, and the body turned yellow after eating. Small domestic ants mostly fly in marriage in the summer, and the male ants die soon after. Female ants nest in the soil, prefer to gather in whole groups, in the evening or on cloudy days out of the hole to breed, the first breeding of sub-ants are worker ants, each year to complete 4 to 5 generations.
Prevention and control methods: (1) Ants in seriously harmed areas should try to rotate with aquatic vegetables or rice, and irrigate water in a timely manner to inhibit ant infestation; (2) Booby trap worker ants: use 0.13% to 0.15% of the ant-killing powder and corn cob powder or cooking oil to mix well, put it in a matchbox, 2 to 3 grams per box, put 1 box per square meter, and then catch a few live domestic ants in the box to eat, they will come to the nest to eat after they return to report the news; (3) for serious harm, use 1 to 3 tubes, 2 grams per tube, Divide into 10 to 30 piles. In places with high humidity, the medicine can be placed in a glass bottle placed on the side, which can be booby-trapped for a long time; or the ant nest can be watered with 90% crystalline dimethods plus lime 1:1 pair of water 4000 times liquid.
(9) Nematodes
Nematodes are parasitic pests that are often less noticeable and usually manifest only as weak plant growth. However, after strawberries are infected with nematode disease, they will hinder the normal growth and development of strawberries, make them less resistant, and be susceptible to pathogenic bacteria such as bacteria and fungi; some nematodes also spread viruses, which can lead to low fecundity of creeping stems, dwarfing of plants, deformation, few flower buds, and significantly reduced yields. At present, there are more than 40 species of nematodes known to damage strawberries in the world, among which the more common ones are strawberry nematode, strawberry bud nematode, strawberry root knot nematode, strawberry root rot nematode. In China, strawberry bud nematode is the most serious pest, and the rate of diseased plants in individual production areas is as high as 40%, and production suffers great losses. Strawberry nematodes are 0.6 to 1 mm long, mainly harmful to buds and leaves, parasitic and feeding on strawberry leaf axils and buds, so that the leaves appear wrinkled, twisted, and smaller than normal leaves, and the flower buds are destroyed. When nematodes interact with pathogenic bacteria, the plant is often dwarfed, and the short stem shrinks to 1 cm tall and expands and divides a large number of new shoots, so that the buds are gathered together, resembling "kale". There are also petioles that are purple-red, or the leaves in the center of the leaf clusters are cone-shaped due to poor development. Strawberry nematodes develop in strawberry buds for 4 ages, completing a cycle in about 2 weeks. Nematodes overwinter in soil and plant debris for 2 to 3 months.
Control methods: (1) remove weeds in the field, strawberry nematode wild hosts such as ferns, mint, rhododendrons, begonias, peonies, etc. should be completely removed; (2) before planting with hot water treatment of dormant mother plants, that is, seedlings are preheated in 35 °C water for 10 minutes, and then soaked in hot water at 45 ~ 46 °C for 10 minutes, taken out and cooled and planted; (3) the soil is treated with kathrendan and lime nitrogen.
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