What are the main grass pests? What are the methods of forage pest control?

The main categories of forage pests: underground pests refer to a class of pests that live in the soil for all or most of the life cycle, mainly to the underground part (such as roots, stems, seeds, etc.) and the near-surface part of the plant, also known as soil pest. There are many kinds of underground pests, strong adaptability, wide distribution, and serious threats to agriculture, animal husbandry and forestry production.

Control method: trapping adult insects. According to the phototaxis of the adults, they are lit to trap and kill at the peak of adult emergence, or the adults are poisoned with sweet and sour venom.

Planting trap crops. In spring, a small amount of amaranth seeds are sown in the nursery to attract pests to the amaranth to reduce the damage to flowers and trees. Artificial killing.

Larvae can be found early in the morning by stirring 3 to 6 cm of topsoil around broken seedlings or along infested branches and leaves remaining at the hole opening. 500 grams of 6 trichlorfon powder per mu, 25,000 grams of soil are mixed well, and sprinkled in the nursery, and the effect is good.

There are many kinds of forage insect pests, mainly including mole crickets, grubs, needleworms, ground tigers, root maggots, root bugs, root aphids, pseudo-ground beetles, crickets, root scales, root leaf beetles, root beetles, root weevils and termites, etc., more than 10 categories, a total of more than 200 species, belonging to 8 orders and 36 families. Underground pests mainly refer to insects that live in the soil and feed on the roots and stems of plants, including ground tigers (interception worms), grubs (mole crickets), mole crickets (Lala crickets), needleworms (yellow worms, wire worms, golden rake teeth), etc. Underground pests are omnivorous, and spring is the most harmful in the spring.

The characteristics of various underground pests are different. Ground tigers feed on the base of young stems close to the ground, biting or biting seedlings. Grubs can directly bite off the roots and stems of seedlings, causing seedlings to die.

After the seedlings are harmed, the soil around the damaged seedlings is loose but not uplifted, and the roots of the seedlings are bitten off or the root bark is bitten, causing the seedlings to wilt and die, but rarely lodging. Mole crickets bite on freshly sown seeds, especially freshly sprouted seeds. After mole crickets damage seedlings, near the roots, the soil is often raised, and the seedlings wither and lodging.

When the damaged seedlings are dug up, it can be seen that the base of the roots or stems of the seedlings has been bitten off, and the wounds are neat. After the needleworm damages the seedlings, there are wormholes drilled at the base of the seedling taproot or young stem, and the seedlings gradually wither or grow poorly.

Forage insect pests refer to the disasters caused by abnormal or inhibited growth and development of forage grass caused by some harmful insects invading forage grass, resulting in a decrease in forage grass yield and seed yield. The more common forage insect pests are mainly as follows:

1.Aphids are harmful to almost all families and genera of forage, the main part of the invasion is the delicate part of the forage, because the aphid bites and absorbs the nutrients of the forage, causing the tender stem and young leaves of the plant to shrink, seriously causing the leaves to turn yellow or even fall off, thereby affecting the photosynthesis of the forage, inhibiting the growth of the forage, reducing the growth of the forage, and reducing the yield of the forage.

2.The elephant mainly harms leguminous forage grasses, and alfalfa is the most important. Blind tsubaki elephant mainly harms the flower buds of forage grass, often causing flower buds to wither and wither, reducing the seed setting rate of forage seeds, not only causing a decrease in seed yield, but also affecting the quality of seeds.

3.This pest is common in leafminer fabulous grasses. The larvae of leaf miner flies often feed on the epidermis of plants, which is very harmful to the leaves of pastures, causing the leaves to form white linear tunnels. The expansion of the tunnel causes the leaves to wither and yellow, which reduces the photosynthesis of forage grass and causes the decline of forage yield.

4.Armyworms are prone to this kind of insect pest in the summer of high temperature and humidity, and the damage is mainly to grasses. The pest mainly eats the leaves of the forage, if the control is not timely, the leaves of the forage can be eaten up within a few days, which brings great harm to the forage production.

Prevention and control methodsThe control of armyworm can be carried out by two methods: manual culling and drug control. The method of manual culling is to drill into the grass pile according to the characteristics of the adult worm of the armyworm, that is, the moth will burrow into the haystack during the day, and insert it in the ground with wheat straw in the pasture, and take off the straw every day, burn the moth or trample the moth to death with fire, and the purpose of eliminating the armyworm can be achieved through this method of eliminating the adult.

First of all, the forage species are different, and the control methods are different.

Take the current high-yielding and high-nutrient forage varieties as an example.

Moisturizing grass, sweet elephant grass, royal bamboo grass, etc.

Downy mildew mainly harms the leaves of pastures, in the early stage of the disease, some polygonal water-soaked spots appear on the leaves, and further the lesions gradually turn yellow, the general edge is not obvious at the beginning, but later it is often limited by the leaf veins to become polygonal, so that the top of the leaves of the diseased plant is yellowed, the diseased leaves are curled to the back, and the back of the leaves gives birth to a lilac mold layer, and the leaves die in severe cases; Plots with severe disease will have a decrease in grass yield.

Control methods: Plant disease-resistant forage varieties. There are great differences in the ability of forage grass to resist downy mildew, and high-resistance varieties can be selected according to local conditions to reduce the occurrence of the disease.

Mowing the grass as early as possible to reduce the source of bacteria, especially in early spring to eradicate diseased plants. Proper irrigation to prevent the grass from becoming too wet. When there are diseased plants in the grassland, Bordeaux liquid, Fumei and other agents can be sprayed.

Rust is a disease that forms rusty spots on the leaves after infecting the leaves, causing its photosynthesis to decrease. Due to the multiple rupture of the epidermis, the intensity of water transpiration increases, and it is easy to wilt when dry and hot. Rust makes the leaves green, shrink and fall leaves early, and in severe cases, it can reduce the yield of plants infected with rust containing toxins, which not only affects palatability, but also leads to poisoning of livestock and poultry after eating.

Prevention and control methods: eliminate host plants, do a good job in field management, and eliminate diseased and residual plants. The diseased grassland should be mowed in time, and it is not suitable to harvest seeds. Choose forage varieties that are resistant to rust.

Brown spot disease occurs when brown spots appear on the leaves, stems, and pods of grass.

Control methods: Wash and disinfect seeds, apply fertilizer reasonably, and maintain a reasonable ratio of nitrogen, phosphorus and potassium fertilizers to improve the disease resistance of plants. When the disease occurs in a large area, it can be sprayed with Bordeaux liquid and lime sulfur mixture for prevention and control.

When using this method for prevention and control, it should be avoided to mix with copper and mercury preparations. In addition, it is not effective to use this method when there is a high temperature in summer and a low temperature in early spring. This agent has a certain corrosiveness, after using the agent should be cleaned with water, and the container containing the medicine should also be cleaned in time.

The main diseases are charcoal disease and leaf spot disease, which can be sprayed with 1000 times of 70% methyl tobuzin wettable powder. The indoor ventilation is poor, and the stems and leaves are susceptible to scale insects, so they are sprayed with 1000 times of 40% oxidized dimethoate emulsion.

For details, please see the figure, forage control should be as early as possible, and pests and insect diseases should be prevented first.