Technical guidance on Wheat planting in Autumn and Winter in 2015 and 2016

Since July this year, there has been more rainfall in the main wheat producing areas, the soil moisture in the soil is generally sufficient, the growth and development of the previous crops is normal, and the suitable time for sowing in most areas is guaranteed. However, there is less rainfall and insufficient soil moisture in some parts of the northwest. At the same time, the meteorological department predicts that under the influence of El Nino, the precipitation in autumn and winter in the northern winter wheat region is less than that in normal years, and the temperature is generally on the high side, and continuous drought may occur in some areas, which is disadvantageous to the sowing and emergence of winter wheat and safe overwintering. In order to effectively improve the sowing quality of winter wheat, cultivate strong seedlings before winter, and consolidate the foundation for a bumper harvest of summer grain next year, sub-regional studies have put forward technical guidance for wheat planting in autumn and winter in 2015 and 2016 for local reference.

1. Huang-Huai and northern winter wheat area

This area includes Hebei, Shandong, Henan, northern Jiangsu, northern Anhui, south-central Shanxi and Guanzhong, Shaanxi. It is the largest winter wheat producing area in China. The production conditions in this area are good, the light and heat resources are rich, the annual precipitation is 400ml / 900mm, the terrain is flat and the soil is fertile. The planting system is mainly wheat and corn cropping twice a year. Wheat is sown in the first and middle of October and harvested from the end of May to the first and middle of June. The main factors affecting wheat production are shortage of water resources, frequent natural disasters such as drought, freezing injury, dry and hot wind, and serious damage to stripe rust, sheath blight, powdery mildew and scab. The key management points of wheat sowing in autumn and before winter in this area include the following aspects:

(1) preparation before broadcast

1. Selection of varieties. Suitable varieties are selected according to local climate, soil, soil fertility, planting system, yield level, diseases and insect pests and so on. One is the selection of seeds due to heaven. According to the temperature conditions, winter and semi-winter varieties are selected, cross-regional planting and selection of unapproved varieties are strictly prohibited, winter varieties are strictly selected in the northern winter wheat region, and winter semi-winter varieties are selected in Huang-Huai winter wheat area. The second is the selection of seeds because of the land. Fertilizer-resistant and lodging-resistant varieties with high yield potential were selected in high-yield fields with good fertilizer and water conditions. Drought-tolerant, water-saving and stable yield varieties were selected in water shortage areas. Drought-resistant and barren-tolerant varieties were selected in dry and thin land. Drought-resistant and fertilizer-tolerant varieties were selected in the dry and fertile land with thicker soil layer and higher fertility. The third is seed selection due to system. Wheat-cotton intercropping requires that wheat varieties are suitable for late sowing and early maturity, so as to shorten the symbiotic period of wheat and cotton, shorter plants, compact plant type and strong edge dominance, so as to make full use of light energy and improve photosynthetic efficiency. Fourth, seed selection due to disaster. In areas with heavy dry and hot wind, varieties with appropriate prematurity, resistance to premature senility and resistance to wilt should be selected to avoid or reduce the harm of dry and hot wind. Fifth, seed selection due to illness. Varieties resistant to rust should be selected in areas with serious rust infection, while varieties resistant to moisture, scab and long dormancy period should be selected in areas with too much precipitation and serious waterlogging. Sixth, seed selection according to quality. Select high-quality varieties with good nutritional quality, processing quality in line with the requirements of finished products, full grains and high bulk density. Seventh, strict introduction and replacement. Change new varieties according to the change of production conditions and increase yield, prevent a large number of introduction, adjustment and frequent replacement of improved varieties without experimentation; while planting main varieties, pay attention to actively introducing new varieties for experiment and demonstration, and do a good job in seed reproduction, determine "succession" varieties, and maintain the quality of seeds used in production.

2. Seed treatment. Strengthen the treatment of wheat seeds, do a good job of seed coating or chemical seed dressing, reduce the incidence of autumn seedlings, depress the source of overwintering bacteria, control the danger of underground pests at seedling stage, and postpone the incidence of wheat stripe rust, powdery mildew, sheath blight and other diseases. According to the disease resistance, disease degree, climatic conditions and cultivation methods of wheat varieties in different places, the fungicides were selected reasonably. Strictly apply the amount of medicine used in seed dressing, prohibit excessive use of medicine; sow seeds immediately after seed dressing, mix and use now, and finish sowing on the same day; appropriately increase the amount of seeds used after seed dressing.

3. Straw is returned to the field. The corn straw should be crushed and returned to the field, and the length of ≤ should be 7cm, which should be scattered evenly on the surface. To turn the crushed straw into the ground, if the deep loosening technology is adopted, the straw must be cut into the soil layer, the rotary tillage depth is more than 15 cm, and the straw should be irrigated firmly after returning to the field, and rake pressure in time if the soil moisture is suitable.

4. Deep ploughing (deep loosening) rake pressure. Deep ploughing 23mur25cm and then rake pressure, or deep pine 30Mel 35cm then rotary ploughing rake pressure, to break bumpy, solid soil, beneficial to the root system, prevent ventilation and run away moisture, and keep the seedlings safe through the winter. The effect of deep ploughing or subsoiling can last for 2 years, deep ploughing or subsoiling for 1 year, and rotary ploughing and soil preparation within 3 years. Deep ploughing and deep loosening of dry land leisure wheat field once a year should be carried out in the first ten days of July, which is beneficial to storing soil moisture in rain and raking before sowing.

5. Water to make soil moisture. Persist in sowing seeds in sufficient moisture to ensure that the whole seedling is sown. When the relative water content of the 40cm soil layer is less than 75%, the soil moisture should be made before sowing. It is necessary to hoe the wheat fields that cannot produce soil moisture in time and irrigate the head water after sowing, so as to prevent soil cracks and reduce the loss of soil moisture.

6. Apply base fertilizer. Soil testing formula fertilization, nitrogen, phosphorus and potassium fertilizer, supplementary application of trace element fertilizer. High-yield fields use nitrogen fertilizer backward technology, nitrogen fertilizer base application and topdressing each 50%, all other fertilizers are applied at the bottom. According to the production experience, the reference values of suitable fertilizer application rates for different soil fertility levels are as follows: 10 kg of pure nitrogen (N), 5 kg of phosphorus (P2O5), 5 kg of potassium (K2O) 2 and 4 kg of potassium (K2O) 2 per mu of low yield fields with a yield of 200m3 kg / mu. In the middle-yield field with a yield of 300,400kg per mu, the application of pure nitrogen (N), phosphorus (P2O5), potassium (K2O) and potassium (K2O) is 12kg, 6kg, 6kg, 6kg, 6kg, 6kg, 6kg, 6kg, 6kg, 6kg, 6kg, 6kg, 6kg and 6kg, respectively. The yield is 400 kg / mu and 500 kg / mu, the pure nitrogen (N) 12 kg / mu, phosphorus (P2O5) 6 kg / mu, potassium (K2O) 6 kg / mu, 60% bottom application, 40% topdressing at jointing stage and all phosphorus and potash fertilizer are applied to each mu. In the super high-yield fields with a yield of more than 500kg per mu, 16 kg of pure nitrogen (N), 8 kg of phosphorus (P2O5), 8 kg of potassium (K2O), 50% bottom application of nitrogen fertilizer, 50% topdressing at jointing stage and all phosphorus and potassium fertilizer were applied.

(2) sowing seeds

7. Suitable sowing time. The daily average temperature for general winter varieties and semi-winter varieties is 16 ℃ and 18 ℃ respectively. To cultivate strong seedlings before winter, winter and semi-winter varieties should ensure that the effective accumulated temperature before winter can reach 550 ℃. At the same time, weather conditions, fertility level, diseases and insect pests and safe overwintering should be taken into account. Generally, from the end of September to the first ten days of October in the northern winter wheat region, the suitable sowing time is October 5-15 in the north and middle of Huang-Huai winter wheat region, and October 10-20 in the south of Huang-Huai winter wheat region.

8. Reasonable sowing quantity. Reasonable sowing rate and suitable basic seedling number are not only the starting point for establishing high-quality population, but also an important measure to build a reasonable population structure and coordinate the relationship between population and individual, wheat growth and development and environmental conditions. The principles to be mastered are as follows: first, the varieties with strong tillering ability and high panicle rate should appropriately reduce the sowing rate. Second, sowing sooner or later, the sowing amount of early sowing is appropriately less, and the sowing amount of late sowing is appropriately increased. Third, the soil fertility level, the basic seedlings with better soil fertilizer and water conditions should be rare, and the sowing rate should be less. Generally, the basic seedlings per mu in the northern winter wheat area is 20-300000, the northern and central Huang-Huai winter wheat region is 15-250000, and the Huang-Huai south is 15-180000. When the daily average temperature of sowing is lower than 15 ℃, the basic seedling will increase by about 10 000 per day, but it should not exceed 350000 at most.

9. Fine sowing. Sow seeds with wheat planters that meet the requirements and qualified quality, and determine the suitable row spacing according to the actual situation of various places, so that the row spacing is the same, the sowing amount is accurate, the depth is the same, the sowing depth is 3mur5cm, and there is no missed sowing and no replay.

10. Crackdown after broadcast. The seeder with ballast should be pressed with sowing, and the seeder without ballast should be suppressed with ballast after sowing. It is necessary to ensure the intensity of suppression, ensure the quality of suppression, stabilize the soil, reduce the loss of soil moisture in the field, promote the growth of wheat seedlings, cultivate strong seedlings before winter, and expand the proportion of strong seedlings.

(3) pre-winter management

11. Water over the winter. For wheat fields that lack moisture and straw returning, rotary tillage and sowing, and wheat fields where the soil is not solid, it is necessary to timely pour over-winter water to ensure safe survival of seedlings. During winter irrigation, it is generally carried out when the daily average temperature is stable at 3Mel 4 ℃ and the water can seep in time, and it is completed before the heavy freezing. Advocate water-saving irrigation, prohibit flood irrigation, hoe in time after irrigation, loosen the soil to preserve soil moisture, prevent surface cracking, and avoid damaging roots and seedlings through wind. For wheat fields with suitable soil moisture, high quality of soil preparation, sufficient bottom fertilizer, normal growth and suitable population, overwintering water can not be irrigated before winter. For wheat fields without watering conditions, hoe should be drawn in time to preserve soil moisture after each rainfall.

12. Chemical weeding. In recent years, the malignant weeds of Gramineae have a gradual development trend, which has a great influence on the yield of wheat. it is necessary to control spring grass in autumn and chemical weeding in autumn, generally from mid-November to early December, 4-leaf stage of wheat, and 2-leaf, 1-heart to 3-leaf stage of weeds. Control wild oats, Aegilops tauschii, ryegrass and other Gramineae weeds. Spray the leaves with 6.9% horse EC 40ml 60ml plus water 30kg per mu. To control Aegilops tauschii and brome, use 30 grams of 3% Shima or 3.6% Koushima 20 grams per mu, and spray 30 kg of water. To control broad-leaved weeds such as Artemisia annua, shepherd's purse, pig calamity, etc., use 75% benzenesulfuron dry suspension 1.0ml / mu, or 10g / mu benzosulfuron-methyl wettable powder 10g, or 20% make it 50ml EC and 30ml water 40kg, spray evenly. To control alkali fescue and hard grass, spray with 25% isoproturon wettable powder 200ml 400g and water 20kg per mu after wheat emergence.

13. Prevention and control of diseases and pests. Wheat fields that are seriously harmful to grubs, golden needles and other underground pests, each mu is irrigated with 40% methyl isophorin EC or 50% phoxim EC 500 ml plus water 750 kg, or 50% phoxim EC or 48% chlorpyrifos EC 250 ml 300 ml, mixed with water 10 times, mixed with fine soil 40 kg, combined with hoeing and applied to the soil. Wheat black leaf miner occurs in serious wheat fields, using 40% omethoate 80 ml per mu, adding 4.5% cypermethrin 30 ml, adding water 40 ml 50 kg spray, or spraying with 1% avermectin 3000 ml 4000 times liquid to treat both wheat aphids and red spiders. To control wheat sheath blight, 12.5% diniconazole wettable powder is sprayed evenly with 30 grams of 12.5% diniconazole wettable powder or 100 grams of 15% triadimefon wettable powder and 50 kilograms of water per mu. Wheat cyst nematode occurred in serious fields, with 5% line enemy granule 3.7 kg per mu, spread along the ridge in the seedling stage, and timely watering to improve the control effect.

14. It is strictly forbidden to eat green. It is necessary to strengthen the management and protection of wheat fields before winter, take good care of livestock and poultry, put an end to the gnawing of livestock and poultry, and ensure the normal growth of wheat seedlings and safe passage through the winter.

II. Winter wheat area in the middle and lower reaches of the Yangtze River

This area, which includes the south of Huaihe River in Jiangsu and Anhui provinces, Hubei and Xinyang City, Henan Province, is one of the main producing areas of winter wheat in China. The climate of this area is humid, the heat condition is good, the annual precipitation is 800Me 1400 mm; the terrain is low and flat, the soil is mainly paddy soil, and the content of organic matter is about 1%. The planting system is mainly rice and wheat cropping twice a year. Wheat is sown from late October to mid-November and harvested from late May to early June. The main factors affecting wheat production were waterlogging and high temperature ripening, which occurred from ear sprouting, scab, powdery mildew, sheath blight and stripe rust. The key management points of wheat sowing in autumn and before winter in this area include the following aspects:

(1) preparation before broadcast

1. Selection of varieties. The varieties with high yield, high quality and strong resistance to moisture, lodging and disease (mainly scab, powdery mildew and sheath blight) were selected. Spring varieties were selected in the south of the wheat region in the middle and lower reaches of the Yangtze River and semi-winter varieties were selected in the north.

2. Seed treatment. Seed dressing with 2% tebuconazole suspension, 15ml 20g per 10 kg seed and 0.5 kg water, can treat both soil-borne and seed-borne diseases such as sheath blight and total erosion disease. Suitable early sowing wheat seeds can be mixed or soaked with chemical control agents such as paclobutrazol, which can play the role of dwarfing and increasing tillers, controlling growth and promoting strength. It is appropriate to soak seeds with 1 gram 15% paclobutrazol powder mixed with 1 kg wheat seed or 100ml 150 mg / L paclobutrazol solution. Attention should be paid to mixing seeds well to prevent the local dosage from being too large and affecting the growth of wheat seedlings.

3. Straw is returned to the field. Rice should control the last water supply time, cut off water for 10 days before harvest, create good soil moisture conditions for wheat sowing, harvest in time after maturity, and prevent excessive "old-age rice". When harvesting rice, the stubble height is less than 10 cm, the straw is chopped up to about 5 cm, and spread evenly. The straw should be returned to the field by deep rotation (or deep ploughing) before sowing, and the depth of rotary tillage should be at least 12 cm (preferably 15 cm) to prevent straw from enriching in the sowing layer.

4. Apply base fertilizer. Weak gluten wheat is generally applied with pure nitrogen (N) 12-14 kg per mu, and the ratio of base fertilizer: balanced fertilizer (applied at the 3-4 leaf stage of main stem): jointing fertilizer (applied at the last 3 leaves) is 7:1:2. The proportion of base fertilizer: strong tiller fertilizer (or balanced fertilizer): jointing fertilizer is 5:1:4 in large area production, and the proportion of base fertilizer: strong tiller fertilizer (or balanced fertilizer, applied at the 3-4 leaf stage of main stem): jointing fertilizer (applied at the last 3 leaves): booting fertilizer (applied at the half of sword leaves) is 5:1:2:2 in high yield field. According to the soil fertility level, the ratio of N, P and K for medium gluten and weak gluten wheat was 1:(0.4 - 0.6):(0.4-0.6), and the ratio of base fertilizer to jointing fertilizer was 5:5. General base fertilizer available urea (containing N46%) 5-10 kg, 45% compound fertilizer (N, P2O5, K2O content are 15%) 15-25 kg.

(ii) Sowing

5. Suitable sowing date. In order to ensure that wheat seedlings form strong seedlings (5-6 leaves on main stem, 2-3 tillers per plant and 3-5 secondary roots) at the beginning of winter, the accumulated temperature above 0℃ should be 500-550℃ from sowing to the beginning of winter. The suitable sowing time in this area is from late October to early November.

6. Reasonable sowing rate. The wheat field sown at the right time in this area has 12- 160,000 basic seedlings per mu. If the sowing time is later than the proper sowing time, the sowing amount should be increased appropriately, and 0.5 thousand basic seedlings should be increased every night, and the maximum number of ears should not exceed 80% of the expected number.

7. Fine seeding. For wheat fields with early harvest, timely stubble, suitable moisture content (soil moisture content below 80% of field water holding capacity) and good soil tillage condition, 2BG-6A type of low tillage drill can be used to complete shallow rotation, grooving, sowing, soil covering and compaction in one operation. Sowing depth 2-3 cm, row spacing 25 cm, medium speed, ensure uniform seed drop, joint between two rounds to coincide, avoid replanting or pulling row spacing, avoid stopping in the field to form seed pile. The two ends of the field should be left blank first, so as to facilitate the turning of the fuselage. Finally, the two ends should be replanted. The dead corners that cannot be sown by the machine should be manually replanted or moved after emergence. When the soil moisture content reaches more than 80% of the field water capacity, the newly improved strip drill should be used to sow seeds to prevent the blockage of the seed outlet and the lack of seedlings and broken ridges.

8. Suppression after sowing. The seeder with a press should be pressed with sowing, and the seeder without a press should be pressed with a press after sowing to ensure the quality of suppression.

9. Mechanical trenching. After sowing, mechanical trenching shall be carried out in due time, and a vertical trench shall be excavated every 2.5-3 meters, with the width of trench 20 cm and the depth of trench 25-30 cm. Dig a transverse ditch 2-3 meters away from the transverse ridge at both ends of the field, and add a waist ditch every 50 meters for longer fields, with a ditch width of 20 cm and a ditch depth of 35-40 cm. Tiantou outfall requires a width of 25 cm and a depth of 40-50 cm. To ensure that the inside and outside of the three ditch communication, pay attention to evenly throw ditch mud, cover wheat ridge, reduce exposed seeds, anti-freezing and seedling protection.