How to control aphids by planting soybeans?

How to control aphids by planting soybeans? Please introduce the method that soybean aphids are important pests to soybean. In recent years, due to the emergence of warm winter and neglect of control, the damage of soybean aphids has become more and more serious year by year. It is predicted that soybean aphids will occur moderately in 2000. Therefore, we discussed the occurrence regularity and integrated control techniques of soybean aphids. 1. Soybean aphids have the habit of tending to tender. The sucking juice of adults and nymphs on the growth point, tender leaves and tender stems of soybean plants were seriously covered with stems and leaves, and young leaves were also damaged, resulting in leaf curling, yellowing, plant dwarfism, poor root system development, decrease in the number of branches and pods, decrease in 100-seed weight, decrease in yield, and even death of the whole plant. In general, the output of the field can be reduced by 20%, 30%, and the serious one can be reduced by 50%. In addition, soybean aphids can also spread mosaic virus disease. 2. The occurrence regularity of soybean aphids has the characteristics of early spot occurrence and rapid spread in the later stage. In mid to late May, after the emergence of soybean seedlings, from the first host plum (Lao Xiyan) moved into the soybean field, began to damage the seedlings, because the migrating plant rate is only about 1%, so only a few pieces occur at this time. In late June, before soybean blossoms, aphids quickly spread all over the field. In the middle of July, when soybean is in full bloom, if the conditions are suitable, soybean aphids propagate rapidly and cluster on the top leaves and branched young stems and leaves of the plant, resulting in the occurrence of aphids. 3. The reasons for the occurrence of emphasis (1) due to the extensive use of pesticides, the number of natural enemies of soybean aphids such as lacewings, aphid-eating ladybugs, aphid flies and parasitic wasps decreased sharply, and the drug resistance of soybean aphids gradually increased. (2) in recent years, the temperature in winter is generally on the high side, and the phenomenon of warm winter appears. The survival rate of overwintering eggs of soybean aphids increases and the number of insects increases sharply. The temperature, rainfall and relative humidity from June to July are also beneficial to the reproduction of soybean aphids. (3) not enough attention is paid to it, and the prevention is not timely. 4. The comprehensive prevention technology should carry out the principle of rational use of drugs and protection of natural enemies. Early prevention and control, that is, the use of drugs when soybean aphids occur to prevent the spread of damage. The main results are as follows: (1) seed treatment and coating with soybean seed coating agent can control underground pests and early aphids. (2) spray powder with 1.5% dimethoate powder or 1.5% Miaojing powder or 2% fenitrothion powder, with a dosage of 1.52kg per mu. (3) spray with 40% dimethoate EC or 50% dimethoate EC or 50% phoxim EC 1500 Mel 2000 times. Click to get more soybean planting techniques click to get more pesticide application techniques click to get more pesticide application techniques