White dew has passed, rapeseed autumn and winter planting will be in full swing. Generally speaking, this year, the main producing areas of rapeseed in the Yangtze River Basin have sufficient precipitation and good bottom moisture, which is conducive to "planting in sufficient moisture" and "transplanting in sufficient moisture", but they also face the problems of complicated and changeable meteorological conditions and increased risk of late sowing, which bring challenges to autumn and winter planting. For this year's oilseed rape fall and winter planting production situation, localities should adhere to the early preparation, early sowing, early prevention and control of the "three early" strategy, focusing on the "selection of good seed, improve the efficiency, disaster prevention" and other key efforts, and strive for a full seedling sowing to cultivate pre-winter seedling, and make every effort to solidify the expansion of area and improve the yield base. The foundation of the expansion of area, raise yields.
(A) zoning classification seed selection.
Widely used in the last five years the new selected varieties, give full play to the advantages of good seed. Rice and oil rotation area for stains, grass damage and stubble shift and other issues, selection of late sowing resistance, resistance to stains, disease resistance, resistance to dense and strong anti-inversion varieties; hills and drought (slopes) for the soil water retention and storage capacity is poor, nutrient elements are easy to lose, prone to winter and spring droughts and other issues, selection of drought-resistant, low boron resistance to high-quality, high-yield varieties; " rice rice and oil," three-maturity system In the "rice-oil" three-maturing system, the goal of early maturity and stable yield, selecting very early maturity and high yielding new varieties, to ease the stubble contradiction; rhizoctonia infected areas to select the rhizoctonia-resistant high-yielding and high-oil new varieties. In addition, we should vigorously promote the thiamethoxam type of seed coating or pharmaceutical seed mixing to reduce the occurrence of pests and diseases and the pressure of late prevention and control.
(ii) Improve the quality of land preparation.
The key is to crush straw and open three furrows. On the one hand, guarantee that the straw is returned to the field. In the former stubble appropriate late harvest on the basis of early stubble, straw crushed to do chopping, spread evenly (straw stubble height of no more than 10 cm, straw chopping length of no more than 8 cm), can be used with high-powered rotary tiller rotary or plowing and deep burying and other ways to ensure that the straw covered in the rows to do the beds level, conducive to weed suppression and drought moisture. On the other hand, standardize the "three ditches" supporting. We should insist on early ditching, deep ditching, avoiding "broken ditch", ensure that the compartment ditch, waist ditch, ditch supporting (waist ditch, ditch depth should reach more than 30 cm, compartment ditch more than 20 cm), drainage and irrigation, reduce the stains; dry (sloping) land and better-drained paddy rice paddies should be vigorously promoted less no-ploughing protective tillage, reduce soil erosion, moisture preservation and drought prevention. Drought prevention.
(iii) Precise and fine sowing.
Timely, dense, fine planting is the key to raising yields. First, the right time to sow. According to the moisture and the previous crop harvest situation, strive to realize the live oilseed rape and transplanted oilseed rape respectively in late September to mid-October and mid-late September sowing, promote the pre-winter fast growth (strive to realize the overwintering of 6 leaves), to cultivate a strong seedling to lay the foundation. Rhizoctonia susceptible area, can be appropriate to delay the sowing period, is conducive to reducing the occurrence of rhizoctonia. Secondly, appropriate dense planting. Seedling transplanting per mu of field preparation seedbed 0.1-0.15 mu, early sowing and early planting transplanting density 0.5-0.6 million plants / mu, late sowing and late planting transplanting density 0.6-0.8 million plants / mu; mechanical direct seeding 200-300 grams of seed per mu. Drone seeding 300-400 grams of seed per mu, acres of seedlings 2-3 million plants; late sowing of rapeseed can easily lead to rapeseed seedling breaks or individual growth is poor, need to appropriately increase the amount of 20% -30% seeding. Third, fine sowing. For seedling transplanting, the seedbed land requirements for ditching for compartments, compartments flat, fine soil, compartments 1.3-1.8 meters wide. For mechanical direct seeding, ensure that the seeding row spacing 25-30 cm, seeding depth 0.5-2.5 cm. For artificial sowing, should be divided into compartments quantitatively uniform early sowing, seed available 2 kg / mu ammonium sulfate granular fertilizer mixed after sowing, sowing timely mulching.
(d) Efficient nutrient management.
The key is to reapply base fertilizer or seed fertilizer with sowing. The Yangtze River Basin autumn precipitation, boron deficiency is serious, nitrogen fertilizer loss rate is high, choose full nutrition oilseed rape special slow-release fertilizer or appropriate to increase the proportion of fertilizer, improve the utilization rate of nitrogen fertilizer. On the one hand, the base fertilizer reduces nitrogen. Recommended use of nitrogen, phosphorus and potassium ratio of 25-7-8 oilseed rape special slow-release fertilizer, or nitrogen, phosphorus and potassium ratio of 20-10-18 potassium sulfate compound fertilizer mixed with 1 kg of borax, rice stubble field per mu 50 kg for base fertilizer, dry (slope) land rape per mu 40 kg for the base fertilizer. Base fertilizer, and in winter and spring depending on the seedling situation in the moisture chasing fertilizer. On the other hand, the seedling fertilizer. Five-leaf period of 5 kg of urea per mu in a timely manner, to promote the growth of seedlings, the use of oilseed rape special slow-release fertilizer oilseed rape can not chase or less chase. On the basic seedling less, the base fertilizer application is insufficient, the seedling potential is obviously weak field, in the 3-5 leaf period should be timely application of seedling fertilizer. In some acidic soil, high yielding fields, there will be a magnesium deficiency, and attention should be paid to spraying magnesium fertilizer (1%-2% magnesium sulfate solution or 1% magnesium nitrate solution, etc.).
(e) Early prevention of pests and weeds.
It is recommended to use seed coating, pharmaceutical seed dressing and other ways to efficiently control underground pests in the seedling stage, aphids, cabbage greenfly, rhizoctonia, root rot and other pests and diseases, and to control the base of pre-winter pests and diseases in advance to reduce the difficulty of prevention and control in the later stage. Oilseed rape 5 leaf period can be sprayed with fungicides such as carbendazim and other fungicides very early control of downy mildew. Grass control should adhere to the principle of "combination of sealing and killing, mainly sealing, early treatment of small, reduce the amount of pest control", immediately after sowing, closed weed control, can choose to use the fine isopropyl metolachloramine, butyl grass amine, dimethyl pentylamine and other closed herbicides, and strive to achieve full coverage; the closed effect of the field is not ideal, as soon as possible in the seedling period again chemical weed control, to mitigate grass damage. The field with unsatisfactory sealing effect should be chemically weeded again in the seedling stage as soon as possible to reduce the grass infestation. For the field after seedling or transplanting pests and diseases occurring in the field heavier fields, should adhere to the "efficient comprehensive prevention" principle, grasp early and small timely pharmaceutical control.
(F) active disaster prevention and mitigation. First, the prevention of stains.
Should pay close attention to weather changes, timely removal of compartment ditch, waist ditch, ditch in the debris and soil, to ensure that the "three ditches" unimpeded. For the fields that have been stained, should be in the clearing of the ditch on the basis of timely plowing and loosening of the soil. Second, timely watering drought. The Yangtze River Basin, especially in the upper reaches of the region is highly susceptible to winter and spring seasonal drought, should be cleaned up early ditches, take the tap watering, mechanical pumping sprinkler, artificial water irrigation, etc., to do fast irrigation and fast drainage, do not leave stagnant water, do not flood irrigation. The occurrence of drought in the field, the timely adoption of ditch water seepage compartment irrigation to replenish moisture, promote the growth of rapeseed, both drought and enhance the cold resistance. No irrigation conditions of the region can be sprayed through the foliar drought water retention agent, growth regulators and other ways to enhance the plant's drought resistance.