First, the main weed species The common weeds in wheat fields in Jiangsu Province are: See Aphrodisiac, Japanese Acacia, Alfalfa, Headgrass, Hardgrass, Poa, Candlegrass, Wild Oatmeal, Bromegrass, Poisonous Wheat, Rice Amaranth, Scissors, Mountain buckwheat, clay paste, chondrus, ratapple, chopped chrysanthemum, chinensis, prickly pea, broiled scallops, scallops, rolled ears, Maijiagong, spotted grass, ground vegetables, Large broccoli, narrow-leaved wild peas, broad-leaved wild peas, small broccoli, leeks, crushed rice bran, skunk cabbage, broccoli, vegetables, dentate sorrel, mother-in-law, persian mother-in-law, erect mother-in-law, mosquito females , water bitter buckwheat, lychee, wild geranium and so on. Affected by temperature, rainfall, soil texture, depth of burial of weed seed in soil, weed propagation pattern, dormancy characteristics, and cultivation system, weed communities in the wheat field and the number of weed occurrence differ greatly among regions and between fields. Second, the characteristics of occurrence Wheat field weeds have a long duration of damage and are inhibited by low temperatures in winter. There are two peaks in the year. The first grass-growing peak was 10 to 30 days after sowing. The main crops were grassy weeds and pigskin, leeks, wild peas, bryophytes, cattle bred, and laverna. The second peak in the past came after the temperature rose in the spring. Early sowing, autumn rain, high temperatures, large amount of grass before winter wheat, heavy rainfall in spring, large amount of spring grass in wheat field, late winter buckwheat production due to less grass, more grass in spring than in winter; In autumn and winter drought and spring rain more years, early sowing wheat field before the winter has less grass, and after winter there are often a large number of spring grass germination. Because of the different crops before the wheat field, the number of weeds in the wheat field and the grass is significantly different. The broad-leaved weeds in the wheat fields of the drought-deficit wheat field are often associated with grassy weeds such as the head grass, candle grass and bluegrass; In the wheat field, grassy weeds are the dominant species, accompanied by broad-leaved weeds such as scallops, rice leeks, and leeks. In the winter wheat field, the damage of grasses and weeds is the main cause. After the spring, broad-leaved weeds such as big broccoli, swine cricket, and leek grow vigorously, which is the main damage period. In winter, when temperatures are low and cold currents invade frequently, weeds that sprout before winter are often naturally dead in winter. Third, control technology In the prevention and control of weeds in wheat fields, based on the comprehensive treatment of agricultural measures, according to the characteristics of the main communities of weeds in the wheat fields in the region, appropriate herbicide formulations should be selected for chemical control. Due to the long period of occurrence of weeds in wheat fields and the obvious difference in the occurrence of weeds in winter and spring, we must focus on prevention and treatment of autumn and winter. Before and after wheat sowing, grassy weeds, pigweed, commonweed, leeks, and large nests should be used. Dishes and other important objects were used for early control; after wheat returned green, broad-leaved weeds were used as the key targets for treatment. According to the grassy phase, herbicides on the road were selected and properly controlled. 1. In order to see the acreage of wheat grown mainly in grasses such as Acacia and Japanese Acacia weeds, 6.9% of hummus can be used in acres (80 mg to 100 ml before winter), and 15% of wheat flour can be used as a straw. Ester) 20-30 grams before winter, 30-40 grams in spring; 50 grams / liter of energy (metastrobin oxazolidinate) cream 60-80 ml before spring, 80-100 ml in spring; 25%, 50% isopropyl Long, 50% hypertonic isoproturon, mu effective composition of 75 grams, and the above single agent and tribenuron, besulfuron methyl compound, mu 40 kg water spray evenly. Pre-winter control before the second leaf stage of wheat seedlings, prevention and treatment in early spring after winter should be appropriately increased dosage. Maiji and Daineng are highly efficient for many grasses and weeds, and they are safe to wheat, and their efficacy is affected by low temperature and drought. In the wheat field with a large number of wild oats, it is possible to control the wheat seedlings during the wintering season with the use of a humophilus (a fenoxazole triterpene). 2. For hard wheatgrass and barnyardgrass, 25% and 50% isoproturon, 50% hypertonic isoproturon, and 75g active ingredient per mu can be used. The time of application is from seeding to wheat seedlings at the third leaf stage; 6.9%. Horses (aloxazolyoxime) 90 to 110 ml, 15% wheat pole (albuteryl ester) 30 to 40 g, 50 g/l high energy (aldoquinoxazon oxazolidinate) 70 to 90 ml , It is better to use pre-winter weeds after treatment. For fields with large amounts of bluegrass and hardgrasses, Sema may be used (Kwastema: methylsulphosulfuron sodium + methylsulfuron-methyl). During winter wheat or early spring control, the pre-winter temperature is generally required. When the pesticides are applied at high doses according to the prescribed dosage and method of application, they are prone to phytotoxicity under the conditions of drought, diseases, field water accumulation, and freezing injury that may cause poor wheat growth. 3. Use wheat bran, leeks and other broad-leaved weeds as the main winter wheat field before winter or early spring to use 20% chlorpropoxyacetic acid 20-25 ml, so that A mixture (20% make it long 20-25 ml) Mix with 20% 25% 4-Chloride 150ml), Benzene Mixture (25% Benzonsone 100-150ml with 20% 2A 4-Chloride 150ml), 36% Pentium (zomatoxifen), Before the winter weed seedlings with 5 ~ 7.5 grams of mu, in early spring mu with 7.5 ~ 10 grams of prevention and treatment; to sow Kwong Artemisia, Mai Jiagong, the main wheat-based wheat, winter wheat seedlings around 3 leaf fast use Elimin (40% flufenazone), 36% Pentium, 75% of the superstars (tribenuron) control. 75% of the superstar dry suspension 1 g single or 0.5 to 1 g superstar plus 20% 2 A 4 chlorine water agent 150 ml compound water 60 kg spray. Maixi (58 g/l difluoxaoxime) has a good effect on most broad-leaved weed stems and leaves such as Poria cocos, Maijiagong, Dazai, Zezhe. Superstars should be applied to the weeds at the 3rd leaf stage, and the superstar wheat fields should not be used to grow broad-leaved crops within 60 days. In wheat fields dominated by weeds such as swine crickets, big broccoli, bryophytes, cockroaches, cockroaches and other weeds, before the spring wheat jointing, when the temperature rises to 6 to 8°C, 48% of Bacillus subtilis is used for 10 to 12.5 ml. Add 20% 2 A 4 Chlorohydrate 125 ml water to 50-60 kg spray; the above-mentioned agents can also be used before the winter wheat seedlings enter the 4-leaf stage, before the cold wave, or use 20% make it Long 20ml or 25ml % Bentazon Water Solution 100 ml plus 20% 2 A 4 Chlorohydrate 150 ml Water 50-60 kg Spray. Note that the use of paraquat should not be used after jointing with wheat. Otherwise, the plant height may become shorter, the ear may become malformed, and the number of grains may be reduced. The use of paraquat enemy before the 4th leaf of the wheat will cause damage to the onion tube and leaves; Bendazosone is safe for wheat seedlings and generally does not produce phytotoxicity, but the use of Bendazosone requires an increase in temperature, otherwise the efficacy will be slow. 4. In order to control grassy weeds before and after autumn sowing, broadleaf weeds should be controlled in early winter or early spring, or the above agents should be mixed and mixed. In order to ensure the safety of post-planting crops, the use of chlorophyllin, a single agent of Astragalus and its formulation