Rice planthoppers can multiply rapidly, which is harmful to rice, how to prevent and control rice pl

Rice planthopper is one of the main pests of rice in production, and there are two main species: brown planthopper and white-backed planthopper. As long as the environmental conditions are suitable, rice planthoppers can multiply rapidly, causing serious harm to rice production. Generally, it can cause a loss of 10% to 20% in rice production, and in severe cases, the loss can reach 40% or 60%, or even no harvest.

In this paper, the characteristics and causes of rice planthopper were introduced, and the corresponding control measures were proposed.

There are two types of adults: long-winged and short-winged. The long-winged adult has a body length of 4 5 mm, grayish-yellow, the top of the head is narrow, protruding in front of the compound eye, there are 3 convex longitudinal ridges on the face, the ridge color is light, the groove color is dark, the black and white are distinct, the small shield on the thorax and dorsal ** has a pentagonal white or blue-white spot, the sides of the female are dark brown or grayish-brown, and the male is black and connected at the front end, the wings are translucent, and the line of the two wings meet** has a black spot; The short-winged female is about 4 mm long, grayish-yellow to pale yellow, with short wings, only half of the abdomen. Egg-tip capsicum-shaped, thin, slightly curved, about millimeters long, milky white at firstbirth, then pale yellow, with 2 red eyespots.

The eggs are laid in the leaf sheath called the middle rib and other tissues, and the egg grains are arranged in a single row into lumps, and the egg cap is not exposed. The nymphs are nearly fusiform about millimeters long, milky white when first hatched, with gray spots, and then pale yellow, with gray-brown or gray-blue markings on the dorsal body back.

Rice planthoppers have stinging and sucking mouthparts, which suck the sap of rice through the mouthparts, thereby interfering with the normal distribution of photosynthetic products of plants, reducing the nutrients transported to the root system, thereby disrupting the normal physiological activities of the root system and accelerating the senescence of leaves. The adults and nymphs of the rice planthopper gather at the base of the rice bush, suck the sap of the stems and leaves through the mouthparts, and consume the nutrients stored by the plant, so that the nutrient accumulation is insufficient, the grains are not full, and the grain rate increases. At the same time, the coagulated saliva secreted by pests can also form a needle sheath, which hinders the activity of the transport tissue in the rice plant.

It causes the rice leaves to lose water and turn yellow, and the lower part of the rice plant turns black, rots and smells, paralyzed and lodging, and falls into the pond and dies, which is called "passing through" and "wearing the top".

Due to global warming, the Pacific subtropical high is significantly enhanced in the dry season, and the north-south airflow convection is frequent, which creates extremely favorable conditions for the migration of rice planthoppers, which has caused the frequency of rice planthoppers to occur more and more frequently in recent years.

At present, several pesticides that are effective against rice planthopper are imidacloprid, thiazinone, enyldimidanthin, thiamethoxam and pymetrozine, which can be divided into two categories: nicotinic insecticides and chitin synthesis inhibitors.

The more commonly used agents for the prevention and control of rice planthoppers are dimidoxam, permethrin, fenvalerate, deltamethrin, thiazinone, pymetrozine, etc., according to the specific situation to choose the most suitable local agents, in addition, when spraying, due to the high temperature, it is recommended that the amount per mu remains unchanged under the premise of more water, thorough, as far as possible to spray the liquid medicine on the whole plant of rice.

The best thing to do is to snefer with imidacloprid, which can be prevented by 2 to 3 times at night.

Hello, the harm of rice planthoppers.

1. Hazards: Absorbing nutrients and water from rice plants, the field first appears yellowing and shrinking for a long time, and then withers, which is called perforation, or puncture. If not prevented in time, it will spread to the whole field within a few days and expand to the surrounding fields.

When the rice planthopper outbreak occurs, the black pressure on the rice plants in the field is full of adults and nymphs, like a pumping machine to suck the water and nutrients of the rice plants, and the whole field is dry, even if the rice is mature and not harvested, the whole field is dried up and lodging in a short time, and it cannot be harvested.

2. Characteristics: long-winged females are long, short-winged are long, light yellow-brown to gray-brown, the top of the head is slightly prominent, the length is slightly greater than or equal to the distance between the two compound eyes, the frontal area has 2 black longitudinal grooves, and the frontal ridge is arc-shaped.

Prothorax dorsal plate, antennae pale yellow. The small shield is yellowish-white to yellowish-brown in the middle, with half-moon-shaped brown stripes on each side, the dorsal plate of the midthorax is black-brown, the forewings are more transparent, and there is 1 brown wing spot in the middle. The eggs are milky white and slightly transparent when first laid, and later turn pale yellow, banana-shaped, and arranged in double rows.

The last instar nymphs have long bodies, and the forewing buds are longer than the hind wing buds, and the nymphs have a total of 5 instars.

The cold-tolerant ability of the white-backed planthopper is stronger than that of the brown planthopper, and the wintering area is slightly wider, and the southern part of Hainan Island and the southernmost area of Yunnan are the year-round breeding areas, and the warm winter year of the northern boundary of wintering is about 26 north latitude.

Causes of occurrence of rice planthopper in rice:

1. The influence of wind.

The adults of rice planthoppers can be divided into two types: long-winged and short-winged, and the body characteristics and colors of long-winged and short-winged are very different. It is a migratory pest that does not usually stay locally and generally uses wind to migrate from southern regions, mainly to survive and reproduce on rice. In the summer, when the wind is more frequent, the migration of rice planthoppers is greater.

Second, the influence of humidity.

The rice planthopper has a high reproduction rate and is relatively dry in early spring, which creates favorable conditions for other rice pests to overwinter, and at the same time, its reproduction rate is relatively fast. In the later period, the precipitation increased and the temperature rose sharply, which provided favorable conditions for the survival of rice planthoppers. The suitable living conditions for rice planthoppers are:

The temperature range is 15-25 degrees and the humidity is around 80%-85%.

3. Influence of cultivation methods.

In the process of rice cultivation, some man-made conditions can also cause rice diseases and pests. When planting rice, some farmers do not strictly follow the standardized planting methods and do not pay attention to the setting of rice row spacing.

Nowadays, rice planting has realized mechanization, if the row spacing of rice is too small, it will cause the partial development of rice rhizomes to be stunted, resulting in poor ventilation of rice fields, and the water replenishment of rice is too frequent, virtually create favorable conditions for the survival of rice planthoppers, increase the number of rice planthoppers, and is not conducive to improving the yield of rice.

When the rice planthopper population is large, it can cause rice lodging in 1-2 days. According to our past experience, rice sheath blight also occurs frequently in years when brown planthoppers occur severely, and when rice planthoppers and rice sheath blight occur at the same time, it increases the difficulty of control. Therefore, when giving plant protection programs, we generally recommend the prevention and control of pests and diseases such as rice sheath blight and rice planthopper.

In order to control rice planthoppers, it is recommended to use pymetrozine, dinotefuran, trifluoropyrimidine, etc. Use 30 grams of 25% pymetrozine per mu, 10 grams of 80% pyritrazine, or 10 milliliters of 10% trifluoropyrimidine.

It is recommended to use less pesticides that are harmful to natural enemies. In order to prevent and control the ** rice planthopper, we need to dispense drugs according to the period. If the rice has not yet reached the maturity stage, that is, when the stems and leaves still have a certain absorption capacity, it can be controlled by systemic medication.

If it enters the yellowing and maturation stage, the absorption capacity of its stems and leaves decreases, and it is recommended to control it with fast-acting drugs. For the control of rice planthoppers, brown planthoppers are more difficult to control, while other white-backed planthoppers and old rice planthoppers are relatively easy to control.

In the later stage, the rice stem is aging, and it is difficult for chemicals to be transmitted to the rice planthopper accumulation area such as the stem. In addition, due to the shade of the leaves in the later stage, it is difficult for chemicals to spray through, and the fields are short of water in the later stage, and many rice planthoppers do not die after being knocked down. At present, there are not many effective control agents for fulminant rice planthoppers, which makes many farmers helpless.

Therefore, it is recommended to add propiconazole and other diseases to control rice planthoppers, and add phosphorus and potassium source reservoirs to improve leaf maturity and increase yield. For the control of brown planthoppers, it is recommended to focus on prevention. Prophylactics that can be used are pymetrozine and dinotefuran.

Generally speaking, more than 5-10 short-winged adults in the booting stage should be prevented in time.

Bring you the best products of Guizhou Lier Chemical. This product is a mixture of nicotine and silkworm toxin pesticides, which has an ideal control effect on pests such as rice planthopper and dimorphic borer. Carbofuran is scattered in the soil as a root zone.

Adults and nymphs of rice planthoppers gather on the underground stems of rice bushes to suck the juice. When disturbed, they jump to the surface of the water or fly to adjacent plots. Sometimes foliar sprays don't work well, but if rhizospheres are used, the effect is much more stable.

Carbofuran is a carbamate systemic insecticide that is contact and gastric toxic. It can control rice planthoppers, as well as rice thrips, rice leaf rollers, rice leafhoppers and other pests. According to the regulations, Carbofuran cannot be used on vegetables and fruit trees.

In the event of this insect pest, it is best to use imidacloprid for control, and it is generally possible to spray 2 or 3 times**.

Be sure to choose some disease-resistant pesticides, and should also be timely fertilization and watering, and there should also be some natural enemies to prevent and control, and also need to loosen the soil in normal times.

Be sure to keep it ventilated, maintain a certain humidity, and then spray more insecticides to ensure that the soil is dry.

When the occurrence of <> rice planthopper is more serious, add 75-100 ml of 5% chlorpyrifos, 10 grams of 50% pymetrozine and 10 grams of organosilicon in each bucket of water, or 75-100 ml of 35% endosulfan, 8-10 grams of 80% enylpyritrazine and 10 grams of organosilicon, mix with water and spray in the morning and evening, and spray 2-3 buckets of water per mu. Pay attention to keep the shallow water layer in the field for 5-7 days after application, pay attention to the effect is obvious, and after 5-7 days, you can carry out secondary spraying according to the control situation.

First, the best formula for the prevention and control of rice planthoppers

1. When the number of insects in the field is large and there is an outbreak trend, the combination of fast-acting drugs and long-acting drugs has a better effect, which can reduce the base number of insects in a short period of time and reduce losses. Add 75-100 ml of 45% chlorpyrifos or 35% endosulfan, 10 grams of 50% pymetrozine or 80% pymetrozine and 10 grams of organic silicon to each bucket of water, mix with water and spray it in the morning and evening, and beat 2-3 buckets of water per mu. After spraying, keep the shallow water layer in the field for 5-7 days, and spray once according to the situation after 5-7 days.

2. In the case of no water and drought in the field, the poisonous soil method can be used after 9 a.m. on a sunny day, 200 ml of chlorpyrifos, 300 ml of 80% dichlorvos, and 30-40 kg of dry fine soil, stirred to make poisonous soil and sprinkled in the whole field. The amount of fertilizer should be applied in kilograms per plant.

3. The preventive drug is to use 20-30 grams of 10% imidacloprid per mu, or 16-20 grams of 25% thiamethoxam, or 20 grams of 20% dinotefuran, which is effective for white-backed planthoppers. 15-20 grams of 50% pymetrozine or 10-15 grams of 80% enylpyrometrozine per mu are effective against three kinds of planthoppers: brown planthopper, gray planthopper and white-backed planthopper.

Second, what should I do if there are rice planthoppers when the rice is about to be harvested in the later stage

1. Near harvesting, you can spray dichlorvos, pymetrozine, endimidazidine, pymetrozine and other control of rice planthoppers, of which the safe interval of dichlorvos is 7 days, pymetrozine is 14 days, endimidine is 14 days, and endizine-pymetrozine is 21 days.

2. It is recommended to use a combination of fast-acting agents and last-term agents to spray, if dichlorvos is used, the concentration should not be too large, and additives such as provincial gongbao should be added if necessary to strengthen permeability and systemic properties. If you are worried about the problem of excessive pesticide residues in the later stage, you can appropriately extend a few days before harvesting.

3. For the situation that there is no water in the field and the base number of rice planthoppers is relatively large, dichlorvos and chlorpyrifos can be mixed with sand, and the choice is sprinkled at noon, this method makes full use of the fumigation effect of organophosphorus pesticides, and the control effect of rice planthoppers is better, and some pesticide residues can also be reduced.

<> rice planthopper can live for about 3-6 days. Brown planthopper, white-backed planthopper and gray planthopper are three common planthoppers that harm rice in China, with brown planthopper occurring and harming the most serious, followed by white-backed planthopper. The feeding habit of the brown planthopper is single, and the adults have obvious tropism to the growth of tender green rice, and only feed on rice and ordinary wild rice under natural conditions, and the adults and nymphs like the shady and humid environment, and the maximum amount of sucking on the plants at the booting stage.

1. Rice planthoppers can live for a few days

1. Rice planthoppers can live for about 3-6 days. There are three main types of planthoppers that harm rice in China: brown planthopper, white-backed planthopper and gray planthopper, among which the occurrence and damage of brown planthopper is the most serious, followed by white-backed planthopper.

2. The brown planthopper has a single feeding habit, and only feeds on rice and ordinary wild rice under natural conditions; The white-backed planthopper mainly pests rice, and also eats wild rice, barley, wheat, millet, corn, sugarcane, early maturing grass, sorghum, etc.; Planthoppers feed on grasses such as rice, wheat, barley, corn, sorghum, and sugarcane.

3. Adults of brown planthoppers have obvious tropism to green rice, and adults with long wings have obvious phototaxis. Adults and nymphs like a shady and humid environment, and the largest amount of sucking is on plants at booting stage. In the growing season, it can reproduce for 1 generation in more than 20 days, and under normal conditions, each female lays an average of 200-700 eggs.

2. Which part of the rice planthopper mainly harms?

1. Rice planthoppers generally hide in the leaf sheath and stem tissues of the lower part of the rice plant in the middle of the rice field. Rice planthoppers have stinging and sucking mouthparts, which can suck the sap of rice through their mouthparts, thus interfering with the distribution of photosynthetic products of plants, resulting in less nutrient acquisition by their roots, and also accelerating the senescence of leaves. The lower part of the rice plant may also turn black, rot and smell, lodging, and die.

2. For rice planthoppers, 10 grams of 25% chlormethalin wettable powder and 20-30 grams of 10% imidacloprid wettable powder can be used for spray control with 50 kg of water, and 30-40 ml of 5% fipronil gel suspension can also be used for spray control with 50 kg of water. Pay attention to the water layer of about 5 cm in the field when applying pesticides, and avoid applying pesticides at noon in hot weather.