Occurrence and control of millet diseases and insect pests
"Plant a grain of millet in the spring, and ten thousand seeds in autumn", the "millet" here refers to the millet. Millet has the advantages of drought resistance and barrenness, strong adaptability and high nutritional value, and is an important crop that adapts to the transformation of dryland in the hills of western Henan into adaptive planting and increases the income of farmers, and the planting area of Luoyang City alone has reached more than 420,000 mu, forming a new pattern of continuous planting of 10,000 mu of slope, a ridge and 10,000 mu of millet, but the recent occurrence of diseases and insect pests in millet has become an important constraint on the high yield and stable yield of millet.
Ding Zhengyu, senior agronomist of Luoyang Plant Protection and Plant Inspection Station
Millet pests and diseases
At present, the spring valley has entered the ear stage, and the summer valley is still the seedling stage. What are the diseases and pests in the millet field at this time?
At present, the main diseases and insect pests that occur in millet fields include thrips, armyworms, millet ash borers, grain plague, white disease, and blight. Among them, insect pests are heavily affected in the spring grain fields, and the earlier they are planted, the more serious the harm. In individual re-occurrence fields, the rate of thrips as pest plants is 50% to 80%, the rate of 100 carnivorous plants is 30 to 50 heads, and the rate of millet ash borer is 5%-6%. Diseases such as grain blast, white disease, and blight occur in local plots.
Harmful characteristics and harmful traits
In July, the high temperature and dry season has arrived, and crops will be eroded by insect pests such as armyworms, thrips, and millet ash borers. At present, the high temperature and drought in the central and eastern regions of China, such as Shandong, Henan, Hebei and other places, need to be prevented in advance. Let's take a look at the pest characteristics and pest traits of these pests.
Armyworm is a common, recurrent pest, the most susceptible to infestation in local areas, the general density of 3-10 heads / m2 in light occurrence years, about 20 heads / m2 in severe plots; the highest density in severe occurrence years reaches 200 heads / m2, and the leaves of millet in re-occurrence plots are eaten up to form a light rod.
Armyworm
Thrips are harmful to millet growth points during the millet seedling stage, causing the leaves to shrink, twist, break or appear worm holes, and the plant cannot grow normally.
Thrips are harmful
Millet ash borers feed on the base of the stem by larvae, causing dry heart seedlings, and the victim plants are easy to break in the wind, sometimes causing white ears of millet. Millet borers are mature larvae that overwinter in stubble or grass.
Millet ash borer is harmful
Comprehensive prevention and control
The drier the weather, the heavier the pest, and comprehensive prevention and control should be implemented according to the growth of millet and the occurrence of insect pests in different regions.
The Xiagu area is still in the seedling stage, and it is necessary to focus on the prevention and control of armyworms, thrips, and millet ash borers. First of all, when the millet seedlings are fixed, the dry heart seedlings caused by the damage caused by the early disease plants of millet white disease and millet gray borer are removed in time. Secondly, do a good job in the early prevention of thrips, millet ash borer and other insect pests. In the millet seedling stage, 2.5% cypermethrin emulsion or 10% high-efficiency cypermethrin emulsion 2000 times liquid spray control, spray twice, each time at an interval of 7 days. It can also treat armyworms.
note
When controlling armyworms, it should be noted that before the third instar of the larvae, when the 100 larvae reach 20 heads, it is possible to choose methylphenidate, chlorantraniliprobamide, high-efficiency cypermethrin or methyl vitamin salt and carbohydrazide, insect nitrile, indipovir compound agent and other chemical pesticides, or biopesticides such as pyridoxine and thuringiensis, spray control in the high incidence of morning and evening larval feeding; or 100 grams per mu with 90% of the enemy centaea. Mix the bran with 1.5 kg of water and make a poisonous bait to spread it in the evening to carry out the poison bait trap; pay attention to the alternating and rotating use of various pesticides to delay the emergence and development of drug resistance. After the armyworm enters the 4-year-old binge eating period, the drug resistance will be greatly enhanced, and the dose of administration should be appropriately increased.
Li Qiaozhi, researcher of Luoyang Plant Protection Plant Inspection Station
Millet disease
In the process of millet growth, not only insect pests, but also common diseases also show a concentrated outbreak trend, common diseases such as grain plague, white disease and blight, which poses a serious threat to the normal growth of millet.
The leaf plague caused by valley blast mostly begins to occur in early July, and spindle-shaped and oval spots are produced on the leaves, generally 1-5 mm long, and the spots can grow into about 1 cm on high-sensitivity varieties. Typical symptoms are grayish-white in the middle of the spot, purple-brown edges, and purple-brown necrotic lines protruding from both ends of the spot. When severe, the spots converge densely and the leaves die.
Leukomorphic disease is a systemic infection. At different stages of millet development, it shows different symptoms such as "gray back, white tip, looking at the old valley, white hair, hedgehog head" and so on. The incidence of bacteria in the soil or fertilizer of the continuous crop is heavy.
Striated blight is mainly harmful to the sheath and stem of millet. The leaf sheath of the affected plant is stalk-shaped, and the spots on the stems are similar to those on the leaf sheath. Diseased plants are generally not easy to draw panicles, and even if they can be pumped, the ears are small and the seeds are thin.
Prevention and control measures
The Spring Valley Area has entered the panicle stage, and in this period, it is necessary to do a good job in the prevention and control of grain plague, blight and white disease. When the old disease strains are found in the field, they should be pulled out in time and taken out of the field to be burned or buried deeply to prevent the spread of germs and can reduce the occurrence of white disease in the next year. So how should we prevent and control grain blast and blight in production?
For the prevention and treatment of cereal blast, you can choose 2% chlortetracycin wettable powder 500 to 600 times liquid, or 40% grams of blast emulsion 500 to 800 times liquid, or 70% methyl tolbuzin wettable powder 2000 times liquid, or 58% metholin daisen manganese zinc wettable powder 600 times liquid for spraying.
To control striated blight, when the rate of diseased plants reaches 5% to 10%, 5% jinggangmycin water agent 600 times liquid or 12.5% enazolisol wettable powder 500 times liquid is used to spray control the base of the millet stem.
In addition, due to the relatively high temperature, try to choose before 10 o'clock in the morning and after 4 pm at the time node of spraying.
Due to the recent heavy rainfall, it is beneficial to the occurrence of diseases such as grain blast and blight, and it is necessary to do a good job in the prevention and control of leaf plague and blight, and timely use pesticide spray control for the occurrence of relatively heavy fields.