At present, autumn grain production has entered a critical period. In order to effectively do a good job in the mechanized production of "three autumn" and ensure that the grains are returned to the warehouse and should be planted as much as possible, the technical guidance for mechanized production of "three autumn" in 2022 is specially formulated for reference by all localities in view of the situation of loss reduction of mechanical harvest, "double night" technology, harvest of lodging crops, and operation of wetland blocks.

1. Machine Harvest Deduction Technology

(I) to choose the appropriate harvest period

Appropriate harvest can increase grain weight, reduce loss, improve yield and quality. Before operation, the suitable harvest period should be accurately determined. Early or late harvest will increase the loss rate and breakage rate. In case of natural disasters and other special circumstances, it can be harvested in advance.

(II) selection of appropriate harvesting methods and tools

When harvesting rice, the full-feed crawler grain combine harvester is generally selected, and the large-feed model is preferred to improve the efficiency and quality of the operation; when harvesting difficult-to-threshing varieties (threshing strength greater than 180g) or lodging rice, the half-feed crawler grain combine harvester can be selected. When harvesting corn, if the moisture content of the grain is below 25%, the corn grain combine harvester is preferred to complete the ear picking and threshing operations at one time, and the longitudinal and axial flow model is appropriate. If the conditions for grain harvesting are not met, the ear picking corn harvester can be used for ear harvesting, and the ear will be threshed after the moisture content of the ear grain decreases or the ear freezes in winter. When harvesting soybeans, the soybean combine harvester equipped with flexible header is preferred; if there is no special soybean combine harvester, it can be realized by adjusting and modifying the grain combine harvester and replacing the flexible header.

(III) machine inspection and debugging

Before operation, carry out a comprehensive inspection and maintenance of the machines and tools according to the product operation instructions to ensure good technical conditions of the machines and tools; adjust the operating parameters of the harvester according to the plot conditions (size, slope, etc.), crop conditions (variety characteristics, maturity, yield level, grain moisture content, straw moisture content, etc.), environmental weather, agronomic requirements (stubble height, straw crushing degree, etc.), and trial collection, trial collection operation distance is generally 30-50m. After the trial collection, the operation effect shall be inspected according to the operation quality standard. If the operation effect is not good, the harvester shall be adjusted and tested again until the operation quality is better than the standard and satisfactory operation effect is achieved.

Precautions for (IV) collection operation

1. Plan the walking route in advance

When corn is harvested, the traveling direction of machines and tools should be parallel to the planting row as far as possible to avoid harvesting in the vertical direction of the planting row. Generally, the centripetal rotation method is used for rice and soybean harvesting. Before the operation, the plot should be checked in advance, the ditches, ridges, passages, etc. in the plot should be leveled, and the wells, graves, pole cables, tree stumps and other insignificant obstacles should be marked, and the route should be reasonably planned accordingly to avoid scientifically. During the operation, the operation shall be carried out in sequence according to the shape of the plot; if necessary, the harvesting road can be opened in advance.

2. Reasonable control of operation speed

Reasonable operation speed should be selected according to the characteristics of the machine, crop yield, plant density, natural height, dry and wet degree, stubble height and other factors; when the crop density, large plant size, high yield, uneven plot, morning and evening, and high crop humidity after rain, the operation speed should be appropriately reduced; when working, generally harvest at low speed first, and then gradually increase to normal operation speed; it is strictly prohibited to use walking gear for harvesting operation; during low-speed operation, the engine speed cannot be reduced.

3. Scientific and standardized driving operation

During operation, the feeding amount should be controlled in real time by adjusting the operation speed and width, so that the machines and tools can work under the rated load, reduce the entrainment loss and avoid blocking failure. Attention should be paid to the width connection to avoid leakage loss between two adjacent operation zones. When turning on the ground, stop the operation, use the reverse method to turn or the circle method to turn at a right angle, and then start the operation after driving in a straight line. Attention should be paid to the harvest of crops near fields, corners and obstacles, so as to achieve full collection and reduce losses.

(V) timely drying

If the moisture content of harvested rice and corn grains does not meet the storage requirements, they should be dried in time. The drying operation shall follow the principle of proximity, contact the drying place in advance, make overall arrangements, reasonably pull and transport, and dry as received, so as to avoid long-term stacking of wet grain.

Rice should be dried at low temperature, and circulating or continuous dryer can be used. The harvested corn kernels should be continuously dried. The harvested corn ears should be stored off the ground first, ventilated and dewatted, and then thresped and dried after the moisture content of the grain drops below 25% or the ears freeze in winter.

Before drying, initial cleaning shall be carried out, with impurity content ≤ 2%, and no long stalks, sack ropes, plastic films and other sundries shall be allowed. The initial moisture content of grains shall be determined, and the moisture unevenness of the same batch of dried grains shall be ≤ 3%. When drying, the temperature of corn grain (excluding seed corn grain) is generally not more than 50 ℃, and the maximum temperature is not more than 55 ℃. The primary precipitation range should be controlled not more than 18% or the average drying rate should not more than 2.5/h to prevent the increase of corn crack rate. The temperature of rice grain is generally not more than 40 ℃, the maximum temperature is not more than 43 ℃, and the drying rate should be controlled not more than 1.5/h, prevent the increase of waist explosion rate. After drying, there shall be no obvious change in the color and smell of the grains, and no heat-damaged grains or burnt grains.

2. "Double Night" Mechanization Supporting Technology

"Double night" refers to the technical mode of late harvest of corn and late sowing of wheat in the area of two crops a year, which can effectively use natural resources such as light, heat, water, and gas to increase the weight of corn grains and avoid the prolific growth of wheat before winter., To achieve annual high-efficiency and high yield.

Mechanization technology of late harvest of (I) corn

Corn late harvest, filling more fully, better maturity, reduced grain moisture content, ear grain solid, is conducive to reducing the rate of mechanical harvest loss, harvester generally do not need too much adjustment. If the ear harvest method is adopted, the moisture content of corn bracts (commonly known as "corn skin") will be reduced, and the friction with peeling rollers will be reduced, which is conducive to reducing ear damage (commonly known as "buttocks gnawing" phenomenon), improving the peeling rate and reducing the loss rate. During operation, attention should be paid to adjusting the spacing between the pressure feeder and the peeling rollers, and appropriately adjusting the pressing degree between each pair of peeling rollers. If the grain harvest method is adopted, "late harvest" can alleviate the problem of high grain moisture content during harvest in Huang-Huai-Hai region, which is conducive to improving the removal rate and reducing the grain crushing rate and loss rate. During operation, attention should be paid to adjusting the speed of the threshing drum and the threshing gap.

In addition, the late harvest of corn, plant water content decreased, straw hardness decreased, toughness increased, plant lodging risk increased, should pay attention to strengthen prevention. If lodging has occurred, refer to lodging corn harvesting technology to carry out operations. The toughness of corn plant straw is enhanced, and the difficulty of mechanized straw returning to the field is increased. During mechanical harvesting, attention should be paid to the quality of straw returning to the field. If the standard is not met, the speed of harvesting should be reduced, or the second straw crushing and returning to the field after harvest should be carried out to create good conditions for tillage and preparation and wheat sowing.

Mechanization technology of late sowing of (II) wheat

In order to ensure the formation of sufficient groups of late sowing wheat, the sowing rate per unit area can be appropriately increased according to the local light and heat resources, variety characteristics, cultivation techniques and other conditions. During sowing operation, according to different models, the seed discharge shaft can be adjusted to the appropriate speed through the gear handle of the multi-speed gearbox, or the working length of the outer sheave of the seed discharge box can be increased (loosen the locking nut of the seed box regulator, turn the handle to pull the core shaft, and adjust the length of the seed bed) to reach the required sowing amount; if necessary, it can be adjusted by replacing the seed discharge sheave.

In order to ensure the nutrient demand of late sowing wheat, the amount of fertilizer per unit area can be appropriately increased according to the principle of matching soil fertility and target yield. The structure of the fertilizer discharging device of the planter is generally not much different from that of the sowing device, and the required fertilizer application can be achieved according to different models and with reference to the adjustment of the sowing amount.

After adjustment, trial sowing shall be carried out to ensure that the operation quality meets the standard. During the operation, the planting should be uniform, the depth should be consistent, no missing sowing, no replay; After sowing, it should be suppressed in time to ensure that the seedlings are complete, uniform and strong.

Harvesting Technology of 3. Lodging Crop

(I) Harvest Lodging Rice

1. Select applicable machines and tools

When harvesting lodging rice, the operation effect of the half-feed grain combine is generally better than that of the full-feed grain combine; if the lodging is serious and the lodging direction is consistent, the half-feed type is preferred; if the lodging is not serious and the lodging direction is staggered, the full-feed type is preferred. When harvesting rice with lodging angle greater than 60 degrees by using the full-feed model, "lodging device" and "anti-lodging elastic teeth" devices should be installed, and the relative position of the reel and the cutter should be adjusted, and the angle of the elastic teeth should be adjusted to tilt backward, so as to reduce the header to a suitable height.

2. Operation Precautions

When the lodging angle is less than 45 degrees, the impact on harvesting operations is limited, and special treatment is generally not required. When the lodging angle is greater than 45 degrees, if the semi-feeding model is selected, forward harvesting or lateral harvesting should be adopted; if the full-feeding model is selected, reverse harvesting or lateral harvesting should be adopted. During operation, the operation speed should be reduced and the operation width should be reduced; the gear should be kept at low speed, and the maximum throttle or medium and large throttle should be adopted; the height and speed of the reel should be adjusted in real time according to the crop conditions; the operation quality should be checked frequently, the concave screen and cleaning screen should be observed, and the machine parameters should be adjusted in time according to the harvest effect; the soil and straw accumulated at the entrance of the cutting knife and feeding cylinder should be removed in time to prevent blockage.

(II) Harvest Lodging Corn

1. Select applicable machines and tools

When harvesting lodging corn, it is preferred to use a high-performance corn harvester with long header length, small inclination angle, and the tip of the divider can stick to the ground; it is also possible to lengthen the dividing tip or install a lodging support device on the header of the ordinary corn harvester to increase the operation stroke of the support and reduce the tilt angle of the header appropriately. When harvesting corn with serious lodging (lodging angle is greater than 60 degrees), on the basis of the above-mentioned adjustment and transformation of the header, replace the iron-rubber mixed peeling roller with a full-rubber peeling roller to prevent the iron roller groove from adhering to the soil and reduce the operation effect; change the impurity discharge roller to floating state, install a powerful fan to effectively discharge the whole corn fed into the header; if necessary, install an auxiliary reel or a spiral recliner on the header, to achieve forced feeding of corn plants; The corn grain combine harvester should also adjust the speed of the threshing drum and the gap of the concave plate to avoid excessive rubbing, resulting in high-moisture grain damage.

2. Operation Precautions

When the lodging angle is less than 45 degrees, the impact on harvesting operations is limited, and special treatment is generally not required. When the lodging angle is greater than 45 degrees, reverse harvesting or lateral harvesting should be adopted under the principle of opposite harvesting. During operation, the load of machines and tools should be reduced, and the feeding speed should be coordinated with the working capacity of each system by means of downshifting and refueling valve, so as to prevent blockage caused by high humidity of corn grains, adhesion of fruit ears to soil and irregular feeding of lodged corn plants after lodging. According to the lodging situation, the distance between the tip of the harvester and the ground should be adjusted in real time to help up the lodging corn as much as possible. The cutting platform should be cleaned in time, prevent the accumulation of straw and soil on the header. In order to facilitate manual picking after machine harvesting, the power of the straw returning device should be disconnected or the device should be raised to the highest position to prevent the ears of missed corn from being broken. If straw needs to be crushed and returned to the field, a second straw crushing and returning operation can be carried out after harvesting.

(III) Harvest Lodging Soybean

1. Select applicable machines and tools

When harvesting lodged soybeans, a soybean combine harvester equipped with a flexible header shall be selected to realize the ground sticking operation of the header. When harvesting soybeans with severe lodging (lodging angle greater than 60 degrees), a "lodging device" and an "anti-lodging elastic tooth" device should be installed.

2. Operation Precautions

When harvesting lodged soybeans, the height of the header should be reduced as much as possible to ensure that the soybeans in the lower position can enter the header. When the lodging angle is less than 45 degrees, the impact on harvesting is limited, and special treatment is generally not required; when the lodging angle is greater than 45 degrees, reverse harvesting or lateral harvesting should be adopted. For other operation precautions, refer to lodging rice harvesting.

Mechanized operation technology of 4. through wetland blocks

(I) create good land conditions

Before mechanized operation, the accumulated water volume of the plot shall be reduced as much as possible to create good conditions for the operation of machines and tools into the field. For the plots with serious accumulated water in the field, drainage and irrigation equipment shall be used to drain the accumulated water in time; for the plots with accumulated water that cannot be drained, ditches shall be dredged for drainage and deep ditches shall be excavated for drainage.

Selection and Adjustment of (II) Machines and Tools

When passing through the wetland mechanized operation, wheeled agricultural machinery is prone to trapping, and crawler agricultural machinery should be preferred. If conditions are not met, wheeled agricultural machinery can be transformed into semi-crawler agricultural machinery (the driving wheel can be replaced with triangular crawler), or a pair of driving tires can be installed to increase the grounding area and reduce the grounding pressure. When the corn in the wetland block is collected in an emergency, the operation can be carried out by adjusting the crawler grain combine harvester, paying attention to adjusting the working parameters such as drum speed and intaglio clearance, and replacing the special corn header or installing the scion plate in the header. In case of emergency wheat planting, multi-functional double operation machines or no-tillage planters should be adopted to reduce operation links and avoid repeated soil damage. The planter can increase the device of covering soil to bridge loose topsoil.

When using crawler type agricultural machinery, the tension degree of crawler should be adjusted according to the situation of the plot. The muddy plot should be adjusted tightly and the dry plot should be adjusted loosely to improve the passing capacity of the machine and reduce the wear of the crawler.

Technical points of (III) operation

Before operation, carefully observe the muddy degree of the plot and take targeted operation measures. During operation, the operation speed should be reduced to avoid rapid advance and retreat; turn slowly to avoid multiple turns and U-turns at the same position; in case of slipping, sinking, tilting, etc., stop the machine in time. During the harvest operation, the grain should be unloaded in time to reduce the weight of the whole machine as much as possible. When the harvesting operation is carried out simultaneously, the quality of straw returning operation should be observed. If the production demand is not met, the second straw returning operation can be carried out in time. When sowing wheat, the straw of the previous crop should be removed from the field as far as possible. The sowing date shall be subject to the moisture content. If the actual sowing date is later than the latest suitable sowing date, the sowing amount shall be appropriately increased according to the number of late sowing days according to the planting experience. During operation, attention should be paid to the influence of machine walking on the sowing quality. Should be appropriate shallow sowing, walking speed should not exceed 5 km/h.

Department of Agricultural Mechanization Management, Ministry of Agriculture and Rural Affairs

Agricultural Mechanization General Station of the Ministry of Agriculture and Rural Affairs

Ministry of Agriculture and Rural Areas Expert Steering Group for the Whole Process Mechanization of Crop Production