Occurrence characteristics and control measures of main diseases and insect pests of cloves

What are the common diseases and insect pests of cloves? How to prevent and cure it? Today, the editor of Huinong Network is going to introduce a fund project that mainly discusses the occurrence characteristics and control management of clove diseases and insect pests. Interested farmers come and learn as soon as possible!

1 diseases of cloves

1.1 Black spot

In the early stage of the disease, there are chlorotic spots on the leaves, which gradually expand to form round or near-round spots, with a diameter of 3 ~ 10 mm, brown or dark brown, with rims but not obvious. The disease spot becomes grayish brown in the later stage, with dense black mildew spots, which are the conidia and conidiophores of the pathogen. The disease spots are connected to each other, so that a large part of the leaves are brown and withered, and wrinkled or even broken. The pathogen of clove black spot is Alternaria. Conidiophores scattered or several roots collected, brown; conidia brown.

1.2 Brown spot

Brown spot mainly harms leaves and can occur in both seedlings and adult trees. In the early stage of the disease, there were small disease spots on the leaves, waterlogged, nearly round, grayish green, with a diameter of 3 ~ 12 mm. When it is wet, there are small mildew spots scattered on it, and when it is serious, the disease spot synthesizes large withered spots, showing grayish brown, full of leaves, such as burning from afar, which will lead to the drying of clove leaves and eventually early defoliation, leaving only a small number of leaves in the whole plant. The pathogen is Cercospora, which also infects camellia, pomegranate, big-leaf yellow poplar, crape myrtle, rhododendron and cockscomb and so on.

1.3 powdery mildew

The disease can occur on both sides of the leaves, mainly in the positive side. In the early stage of the disease, sporadic small powder spots were produced on the diseased leaves, which gradually expanded, and the powder spots were connected to cover the leaf surface. In the later stage of the disease, the white powder layer became sparse and dusty, and small white particles appeared on it, and finally turned into black powder-closed capsule shell. It is the sexual age of the disease, and the white powder layer is asexual. The disease of clove powdery mildew is caused by clove fork powdery mildew. The closed cysts are spherical or oblate, with several bifurcations at the tip of the accessory filaments; there are several ascomycetes in the closed cysts, oval to broadly elliptic; ascospores 4 ~ 6, elliptic or ovate.

1.4 Alternaria leaf spot

The disease spot is a small round spot of 1 ~ 5 mm, the middle white edge is dark brown, accompanied by purple halo, the disease spot grows a large number of small black spots when wet, and the disease spot penetrates both sides of the leaf. The pathogen is Alternaria alternata. The black spot on the leaf spot is conidia disc, conidia spindle-shaped, with 4 septum divided into 5 cells, 3 light brown in the middle, colorless at both ends and long at the top.

3 flagella.

1.5 Alternaria oryzae leaf spot

The lesion is nearly round or irregular in shape, with a diameter of 10 ~ 30 mm. When the lesion is largest, it can occupy more than 1 inch 2 of the leaf area. The disease spot is grayish brown, and there is a wavy purple-black band at the junction of the disease and health, on which a large number of small black spots are scattered, and the diseased leaves are deformed in the later stage. The pathogen mainly invades from the leaf tip. The pathogen is Alternaria alternata. Conidiophores small, unbranched. The conidia are oval, unicellular and colorless, with a size of 15.5 ~ 17.5 μ m × 3.84.2 um. The small black spot on the leaf spot is the conidium of the pathogen, oblate, with a diameter of 100 ~ 120 μ m.

1.6 nematode leaf spot

It is reported that the disease occurred in India. At the initial stage, the young water-stained disease spots appeared on the leaves, the diameter was up to 1 ~ 3 mm, the edge was yellow, the center was obviously white, in most cases, the disease spots were United, and the typical symptoms of leaf rot appeared, and the leaf tip withered up to half of the leaves. The pathogen is a fungus of the genus Cladosporium. The conidiophores are erect and septate and grow in bundles on the back of the leaves. There are branches, each branch can produce bottle peduncle, and finally produce conidia, rod-shaped multi-septate.

1.7 return to blight

The disease is mainly common in Sumatra and other places, but it has not been seen in China at present. The bark and xylem of the infected branches turn reddish brown, which can produce small black spots, grow yellow mucus above, and make the surface of the diseased part rough, individual branches wither back, and in serious cases, the whole plant dies. The pathogen is caused by Cryptosporium fungi. This is a kind of wound parasite with sporadic conidia with long neck, linear conidia and yellow single spore. The ascus is long-shaped without accessory filaments and contains 8 spores, which are filamentous and unicellular.

1.8 bacterial blight

Clove bacterial blight, also known as bacterial leaf spot, mainly infects leaves [8]. There are four main types of symptoms on the leaves: one is the spot, which begins to occur in the lower leaf, becomes a chlorotic spot, soon turns brown, and then the center of the spot is grayish white; the other is the star spot, in which one or more brown lines are connected with other small spots to form a star shape. Third, flower spots, spots continue to expand outward, forming concentric wheel patterns, the center gray-white, and finally give birth to corrugated lines around the round spots, making the round spots look like flowers; fourth, scorched, the whole leaves turn brown, dry curl up on the branches, from a distance, it looks like a fire, and when serious, the whole bush dies. The pathogen of the disease is bacteria, Pseudomonas clove, which belongs to Pseudomonas. The cell is solitary, rod-shaped, with 1 ~ 2 flagella at one end, and can swim in water without capsule. Gram staining was negative.

1.9 algal spot

The lesion was nearly round or irregular in shape, with a diameter of 5 ~ 12 mm, initially purplish red, then purplish black in the center, and still purplish red at the edge. A large number of golden felts grow on the back of the lesion. The pathogen is a parasitic algal plant. The vegetative bodies of pathogenic algae spread on the disease spot to form dense near-round felt, and sporangium and zoosporangium grew in the later stage. The tip of the cyst pedicel is enlarged with 8 ~ 12 small peduncles, each pedicel terminal with an oval, yellowish-brown zoosporangium, which releases double flagella and oval zoospores after maturation.

1.10 Root knot nematode disease and root rot disease

It belongs to root disease. Nematodes can cause weakening of plant growth, yellowing of branches and leaves and root knot, while root rot can cause root rot. If it is light, it will stop growing, and if it is heavy, it will wither and die.

2 lilac pests

2.1 scale insects

There are many species of scale insects that damage cloves, such as cotton scale, Euonymus, etc., the insect pests mainly damage the branches of cloves, and in serious cases, the leaves wither and the branches produce black mildew spots.

2.2 submerged leaf beetle

Ligustrum lucidum, also known as Ligustrum lucidum, belongs to the family Coleoptera, mainly harming cloves. For three generations a year in North China, adults mainly feed on flakes of leaf meat, resulting in round or irregular spots on the leaves, while the larvae sneak into the leaf epidermis and form curved latent tracks in the epidermis, resulting in damage to leaves and scorching of a large number of leaves.

In addition, pests that harm cloves also include aphids, leaf moths and so on.

3 Control and management of clove diseases and insect pests

3.1 Chemical control

In early spring, protective agents such as Bordeaux solution, Dyson zinc and stone-sulfur mixture were sprayed in advance. After the onset of the disease, fungicides such as chlorothalonil and carbendazim were sprayed in time, or 800 times of 50% carbendazim was sprayed every 15 days after cloves were spread, or 1000 times of 50% carbendazim wettable powder was sprayed for 2-3 times. Bordeaux solution of 1 ∶ 1 ∶ can also be sprayed before or at the early stage of the disease to maintain new leaves and increase disease resistance.

600 ~ 800 times of 3% Zhongshengmycin wettable powder, 300 ~ 500 times of 2% Chunramycin wettable powder, 500 ~ 700 times of 60% ethyl phosphine aluminum wettable powder, or 600 ~ 800 times of 20% clozole wettable powder, or 400 ~ 600 times of 30% copper succinate wettable powder were sprayed to control bacterial diseases. When the disease is common, 72% agricultural streptomycin sulfate soluble powder 2000 ~ 4000 times, or 88% streptomycin hydrate soluble powder 3000 ~ 4000 times, or 20% thiazole zinc suspension 600 ~ 800 times, or 25% complex ammonia copper solution 400 ~ 600 times, etc., shall be sprayed once in 5 ~ 10 days according to the incidence of the disease.

To control scale insects, the tree trunk can be sprayed with stone-sulfur mixture during the dormant period. Spraying should also be applied in early spring, once every 14 days in June, and other fungal diseases can be prevented and controlled at the same time. When the larval activity was investigated, 80% dichlorvos 1 000 ~ 1 500 times or pyrethroid pesticides were sprayed immediately, once at an interval of 14 days, and repeated twice. When the female is fixed to damage the branches, she can also use a knife to carve the epidermis of the stem, and then apply medicine, so that the plant will suck the drug and kill the worm. The leaves of red spiders were sprayed with 0.2 ~ 0.3 Baomedo stone sulfur mixture and 20% triclofenac sulfone diluted 500 times. The effect of mixed use of the two liquids is better, spraying once in 5 ~ 7 days and using 2 ~ 3 times continuously.

In the case of weak growth, cloves are occasionally damaged by cotton aphids, jumping beetles, wasps and other pests, causing juices to flow out of the wound. For careful investigation and timely discovery and timely treatment, you can choose 10% imidacloprid wettable powder 2000 times, or 4.5% cypermethrin EC 1 500 times + good wettability 3 000 times, or 40% chlorpyrifos EC 1 500 times. Or 20% dimethoate EC 3000 times, 40% omethoate 800 ~ 1000 times or avermectin spray control. Attention should be paid to the rotational use of chemicals in prevention and control.

3.2 Field management

3.2.1 selection of excellent varieties

The selection of excellent disease-resistant varieties during planting is also very important for disease control.

3.2.2 reduce bacterial sources

To strengthen the management after planting, we should clean the countryside in autumn and winter, remove the dead branches and fallen leaves and burn them in time, and reduce the source of pathogen infection.

3.2.3 pruning branches

Clove cultivation is not easy to be too dense, need a large number of pruning, if there are several bifurcated trunk, should be weak to stay strong, oblique to stay straight, retain 1. During the growing period, pruning and shaping should be done in time to control the density of branches and leaves, which is conducive to ventilation and light transmission.

3.2.4 strengthen drainage and irrigation

Young lilac root system is weak, not resistant to drought, young trees under 3 years old need irrigation in dry season; flowering and fruiting period is easy to cause falling flowers and fruit in dry season, and irrigation should also be done; in rainy season, attention should be paid to timely discharge of stagnant water to reduce humidity and prevent stagnant water.

3.2.5 fertilization

Timely and appropriate amount of phosphorus, potassium fertilizer, less nitrogen fertilizer, application of barnyard manure or compost and other organic fertilizer, mixed with appropriate amount of calcium superphosphate and plant ash.

3.2.6 weeding and soil cultivation

Weeding and soil cultivation is carried out from July to October every year. Clove trees have shallow roots and cover the plants with grass. Be careful not to hurt the roots and prevent the occurrence of nematode disease and root rot. Fine roots should not be exposed on the soil surface. If exposed, fertile loose soil should be used to cultivate soil for 2 ~ 5 cm.

These are all the contents that the editor has sorted out for you today. Welcome every farmer friend who needs to come to HuiNong Network to learn!

The main diseases and insect pests of flowers and trees in autumn and their control

After entering autumn, the temperature and humidity are moderate and the light is good, which creates favorable conditions for the breeding, reproduction and infection of some bacteria, and often causes serious harm to some flowers and trees. The symptoms and control methods of several common diseases and insect pests are introduced as follows:

Brown spot disease

The main damage to leaves. Brown spots appeared on the leaf surface at the initial stage of the disease, and then with the continuous development of the disease, the disease spot gradually expanded and connected into large spots, which were mostly irregular due to the limitation of leaf veins. There is a faded halo on the periphery. The edge is reddish brown, the center is grayish white, and black dots (conidia) are produced in the disease spot in the later stage. when the disease is serious, the disease spot occupies all the leaves. The leaves of the injured plants were easy to fall off, and if they were seriously damaged, the whole plant did not exist, forming a smooth rod, and finally the whole plant gradually withered from bottom to top. Among them, rhododendron, daffodil, jasmine, clove, sweet-scented osmanthus, pedicel begonia, lotus, water lily, heather and other flowers suffered seriously.

Prevention and treatment: cut off diseased branches and leaves in time and burn them centrally to reduce pathogens. Before the onset of the disease, spray 1-1-200 Bordeaux every 10 days, which can play a preventive role. At the initial stage of the disease, 65% of Dysen zinc wettable powder or 1000 times of methyl topiramate can be sprayed. The root can also be irrigated with 50% carbendazim 200 times solution.

Powdery mildew

Powdery mildew is mostly distributed in the front of the leaves of Euonymus tomentosa, but also on the back of the leaves. A single lesion is round, white, enlarged and irregular after healing with each other. When the superficial white powdery hyphae and spore layer were wiped off, the primary disease showed yellow round spots. In severe cases, the disease of new shoots can reach 100%. Sometimes the diseased leaves are shrunk and the diseased tips are twisted and atrophied.

Prevention and control methods: ① properly thinning branches to enhance plant permeability, cutting seedlings do not have much density, etc., are the problems that should be paid attention to in the prevention and treatment of this disease. ② chemical control, can spray 20% trimethoprim 2000 times, or 50% topiramine, 50% carbendazim 500x solution, as soon as the disease begins to appear, repeat once in 10 days or so, spray 4 Mel 5 times.

Anthrax

The disease mainly occurs in leaves and can also damage petioles, twigs, stems, buds and petals. After the damage to the leaves, the initial stage showed a small round pale water-immersed dot, and then gradually expanded, showing a grayish brown, surrounded by a brown edge, slightly raised. Finally, the central part of the lesion faded from gray to white, and the disease was extremely thin, translucent and easy to perforate. There are also some disease first from the tip of the leaf, and then spread to the leaf. The disease spot can often reach the whole leaf surface, and the leaf will die at last. Some plants are constantly falling off and seriously damaged, often without a single leaf in the whole plant. When the petiole was damaged, the diseased part became brown, slightly sunken, spread to the main vein, branch vein and even the whole leaf browned, and the disease spot continued to spread downward, from petiolule to total petiole, branchlet, and even stem browned and withered. In moist conditions, reddish slime is often produced on the disease spot, which is the spore disk produced by bacteria. The damaged plants, the light ones affect the normal growth and development, lose the ornamental value, and the severe ones lead to the death of the whole plant. Camellia, rose, Milan, white orchid, lily, magnolia, southern bamboo, evergreen, gentleman orchid, cactus, plum blossom, orchid and other flowers are prone to this disease.

Control methods: strengthen cultivation management, properly increase phosphorus and potassium fertilizer, avoid partial application of nitrogen fertilizer, watering should not be too much, basin soil should not be too wet, at the same time, ventilation and light transmission should be enhanced and humidity should be reduced. Diseased leaves and petioles should be cut off and burned immediately, and dead plants should be removed in time. During the onset of the disease, 50% anthrax Fumei wettable powder can be sprayed 500 times, 70% methyl topiramate 1000 times, and 75% chlorothalonil 800x solution, sprayed once every 10 Mel 15 days, 2-3 times continuously, and the control effect can be improved by using agents alternately.

Camphor green butterfly

It mainly harms camphor tree, nan, laurel, Magnolia, Michelia, incense, avocado, citrus and so on. The newly hatched larvae first ate the eggshell, and then ate the mesophyll on the back of the tender leaves. After the 3rd instar, the food intake increased, and the leaves could be eaten up, and the 2-3-year-old larvae suffered the most. Seriously affect the growth and development of plants and ornamental.

Three generations of 2Mel occurred in one year, and the pupae were suspended on the middle and lower branches of the parasitic host to overwinter. Eclosion began in the middle of April and the end of May. The overwintering generation and the first to third generation larvae were from mid-May to mid-June, from early July to mid-August, and from late August to late September, respectively. The adults emerged at night and flew in the forest for 2 days after Eclosion, foraging for nectar as supplementary nutrition. A few days later, courtship, mating and spawning. Oviposition 1 at the tip of young leaves, occasionally 2. Each female laid 18 eggs and 34 eggs. The 5th instar larvae shed their skin every 4 days, and the body increased with the instar, and the 5th instar larvae ate the largest amount of food. Each larva ate 5 pieces of camphor leaves every day. The larvae are mature and crawl behind the hidden twigs and leaves, fix the tail with silk, and pupate for 3 days. The egg stage is generally 4 times 6 days, the larval stage is about 20 days, and the overwintering pupa stage is about 90 days. The suitable temperature for larval development is 20 ℃ 28 min.

Control methods: during the spawning period of adult ①, inspect the camphor seedlings in the nursery and remove the eggs laid in Xuanjian in time. At the initial stage of ② larval occurrence, 40% isamidophos EC was sprayed 1500 times. ③ combined with winter management to remove overwintering pupae.

Crape myrtle scale

It mainly harms crape myrtle, pomegranate and mulberry. Adults and nymphs suck harm on bud axils, leaves and branches and secrete honeydew, resulting in blackening of branches and leaves, shedding leaves, affecting growth and losing ornamental value.

There are 3 generations of 2MUR in one year. Overwintering with nymphs in the cracks in the branches. Continue to eat the harm in the following year. In April, the mature male nymph pupated and mated with the female, and died shortly after mating. Female adults begin to lay eggs in early May. The first generation of nymphs hatched from late May to early June. The second generation of female adults laid a large number of eggs in the first and middle of August. From late August to early September, nymphs hatched in large numbers and developed irregularly. There is an overlap of generations. The insect bodies are mostly distributed in the cracks and depressions of branches and tree trunks. A few are distributed at the base of the back of the leaves, and the shady side is more than the sunny side on the branches.

Control method: ① uses bamboo or brush to scrape off tree trunks and insect branches. At the end of ② nymph incubation, 2 Mel could be sprayed continuously for 3 times, with 25% imidophos 600 Mel 800 times and 40% phosphorus trapping EC 1500 Mel 2000 times. ③ is combined with pruning to remove and burn insect branches.

Spodoptera litura

There are yellow diamondback moth, brown edge green diamondback moth, flat diamondback moth and so on. It mainly harms Chongyang wood, poplar, willow, elm, Robinia pseudoacacia, cherry blossom, red maple, begonia, wax plum, crape myrtle, sweet-scented osmanthus, big leaf yellow poplar and so on.

There are two generations a year, and the larvae are cocooned in the shallow soil layer to survive the winter. Adults lie dormant during the day, fly at night, and have phototaxis. Adults mate and lay eggs. Dozens of eggs are often concentrated on the back of the leaves, arranged in the shape of fish scales. The egg period is 5m / L for 7 days. The newly hatched larvae did not feed, but ate the molted skin and mesophyll after the 2nd instar, pierced the leaf epidermis after the 3rd and 4th instar, and nibbled inward from the leaf margin after the 6th instar.

Control methods: ① according to the clustering of newly hatched larvae of diamondback moth, the damaged leaves are transparent and withered, and the target is significant, so it can organize manpower to remove insect leaves. ② light traps and kills a variety of adults of stinging moths to prevent spawning. ③ mastered the spraying of the 3rd instar larvae of diamondback moth. Use 10000 times of 20% diflubenzuron suspension, 2 000 times of 50% phoxim EC, or 1000 times of 50% marathon EC. ④ can be combined with pruning and pruning in winter, pruning pupae, centrally burning cocoons, loosening soil on tree plates, fertilizing and other measures to eliminate other cocoons of stinging moths.

Yellow poplar inchworm

It mainly harms silk cotton wood, yellow poplar, Wei spear, elm, poplar, willow and so on. The larvae gather the leaves to feed, eat up the leaves and eat the skin of the twigs, resulting in the death of the whole plant.

There are 3 generations of 2Mel in a year, overwintering as pupa. Adults inhabit hidden places of branches and leaves during the day, move at night, mate, and lay eggs on the back of the leaves, arranged in double rows or blocks. There are dozens to more than a hundred eggs. Most of the eggs hatched at 5: 00 in the morning, the leaves were harmed, the skins were eaten, and the mature larvae fell into the soil and pupated. The flying ability of adults is not strong and has strong phototaxis.

Control methods: ① adult emergence period, the use of light trapping. Taking advantage of the weak flying ability of adults and concentrated on the upper and lower parts of parasitic plants in the morning and evening, ② hunted and killed with simple instruments. During the larval damage period of ③, 50% imidathion emulsion, 50% fenitrothion EC and 25% carbaryl wettable powder were sprayed, and the control effect was better. During the peak period of adult oviposition, ④ can remove the egg mass and newly hatched larvae from the weeds around the rhizosphere and plough the rhizosphere soil in winter to kill the overwintering pupae.

Common diseases and insect pests of lotus flower and their control measures

Lianwu mainly grows in the south, and it can blossom and bear fruit many times in its life. Because of its particularity, it is loved by many people, so what are the common diseases and insect pests and control measures during the planting period?

Main diseases of lotus flower

1. Anthrax

It is the most important disease in production. In addition to harming the fruit, it can also infect leaves, form withered disease spots and become the source of infection. whether the field management is good or not has a great relationship with the prevention and control of this disease. 56% Teketo wettable powder, 50% carbendazim wettable powder and 43% Chunleimycin wettable powder can be used for prevention and treatment. Other optional medications include 50% carbendazim, 40% carbendazim, 50% carbendazim, 50% topiramine and 75% chlorothalonil. In addition, good fruit tree management, pruning diseased branches and growing branches can make the fruit trees well ventilated, which can not only prevent the occurrence of diseases, but also facilitate the uniform distribution of chemicals. Bagging is also a good protective measure, in the lotus flower young fruit (hanging bell period) first apply chemicals to prevent infection, at the same time immediately bagging, can also get a good prevention and control effect. Diseased branches, fallen leaves and fallen fruits in the field should be burned or removed from the orchard to reduce the density of pathogens and reduce the occurrence of diseases.

two。 Fruit rot

Pestalotia is one of the most important pathogens in the tropics, with more hosts. Betel nut, coconut, mango, guava and other fruit trees can be damaged, mainly leaves or fruits. At the beginning of the diseased fruit, waterlogged spots were formed, and there were black spots on the enlarged surface, and finally the fruit became dark purple or black, hung branches, dehydrated and withered and fell. Chemical control of available Zinc, Aluminium ethylphosphate, Trichoderma, etc.; physical control can be used to prevent the invasion of bacteria; isolation of suspicious hosts: avoid mixed planting or adjoining of a variety of fruit trees, if mixed planting, should be applied to other fruit trees at the same time to reduce pathogens, reduce the occurrence of diseases; clean orchards to avoid spread infection.

3. Epidemic disease

Mainly damage mature fruit, first form discoloration spot, the affected part expands rapidly, covered with white silk, about 2mur3 the whole fruit will rot, and has a strong sour taste, lure fruit flies to come, contribute to the spread of the pathogen. The first priority for the prevention and control of blight is field hygiene, and the removal of pathogens is the primary measure, such as the removal of diseased fruits. At the same time, avoid composting and the coexistence of epidemic fruit and epidemic fruit, in order to reduce the density of bacteria and shorten the residual period of bacteria, the use of chemicals to kill the remaining blight bacteria on the surface of the soil and reduce the re-infection of bacteria. The fruit of lotus flower should be avoided from growing on too low branches, so the branches near the ground should be pruned, and the orchard should use grass vegetation to prevent Rain Water from spattering and block infection. when the disease in the orchard is serious, fungicides can be sprayed on the surface of the tree crown and below 1.5m of the tree trunk to restrain the spread. Available fungicides include Trichoderma, Aluminium ethylphosphate, thiophanate methyl and so on.

The main insect pests of lotus flower

1. Oriental fruit fly

The first pest of lotus fog is Drosophila oriental fruit fly. The female lays eggs on the surface of the fruit, and the larvae eat the fruit, causing the nearby pulp to rot and cause the fruit to fall. The mature larvae come out of the pulp and pupate in the ground. In terms of control methods, toxic methyl clove oil, trapping lamp or fibreboard can be hung during the fruiting period to trap and kill males, which is ineffective to females, and it is necessary to hang nearby orchards at the same time, otherwise the effect is not good; chemical control can spread 25% marathon wettable powder or 5% parathion emulsion 200 times mixed protein hydrolysate (or 3% brown sugar water), spray once every 7 days, spray small trees and spray to the crown, grass or tree leaves near the orchard. Clean the orchard, pick up the fruit buried in the soil or flooded; fruit bagging.

two。 Thrips

There are ventral hook thrips that harm leaves and flower thrips that harm floral organs. The former is more in the dry season, adults and nymphs feed on the leaves, and secrete and excrete and contaminate the leaves, making the leaves rust, curl and deciduous, affecting photosynthesis. The latter harms the floral apparatus in the flowering stage, resulting in deformed fruit, rust fruit spots and so on. For prevention and treatment, you can choose 3000 times of 25% cyhalothrin emulsion, 2000 times of 28% cyhalothrin (kung fu) emulsion, 1500 times of 2.8% deltamethrin emulsion, 1000 times of cis-cypermethrin emulsion or 48.34% carbosulfan (good year winter) emulsion 1500 times. The application of beta-cyhalothrin, deltamethrin and cis-cypermethrin was stopped 6 days before harvest, cyhalothrin 18 days before harvest, and carbosulfan 25 days before harvest.

3. Green leafhopper

It often occurs in dry season and during the extraction of new leaves. Adults and nymphs feed on tender leaves and shoots, which hinder the curling growth when they are young. The chemicals used to control thrips can effectively control green leafhoppers. 50% parathion 2000 times solution is also available.

The above are the prevention and control measures of common diseases and insect pests in lotus. If you do not know or want more knowledge about diseases and insect pests, you are welcome to pay attention to the first Pesticide Network in China. In addition, it should be noted that Lianwu likes warm and cold, and the optimum growth temperature is 25-30 ℃. There is no frost damage in winter, the buds and young fruits will fall off due to cold injury at 7 °C, and the fruits close to harvest will also fall off at 10 °C. Nelumbo nucifera has a high requirement for water, but it has strong adaptability to different soil conditions. Lianwu likes moist soil and needs an adequate water supply all the year round. Where the water edge of the lotus fog, the growth will be strong, and consumption tolerance is also strong, often soaked areas also grow normally, blossom and bear fruit. At the same time, the requirements of soil conditions are not strict, sand, clay, red soil and slightly acidic or alkaline soil can be planted, and the economic cultivation of slightly alkaline clay loam with better irrigation conditions is better.