Green aphids appear on spinach leaves. What is the reason?

First, abnormal weather leads to aphids. In recent two years, the temperature in Jiayin Farm has obviously increased, which is 0.7℃ higher than normal and 2.9℃ higher than the same period last year. The average precipitation is 80.3 mm, which is 6.4% less than normal and 194.5 mm less than last year. The average relative humidity is 69%, which is lower than 80% in normal years. In April, the temperature is higher, the precipitation is less, and the relative humidity is lower, which is very beneficial to the occurrence and reproduction of aphids (the optimum temperature of aphids is 14-26℃, and the optimum relative humidity is 50-85%).

Second, the improvement of the ecological environment is conducive to the growth and reproduction of aphids. In recent years, Jiayin Farm has intensified afforestation and ecological environment protection, and the ecological environment has been continuously improved. The green area of the jurisdiction is increasing, and the forest coverage rate is increasing. In addition, April is the season when poplar leaves bloom, seedlings grow vigorously, and aphids are rich in food, which is conducive to growth and reproduction, leading to aphids.

Third, the decrease in the number of natural enemies leads to aphids. In recent years, due to a large number of pesticides sprayed in agricultural production, the number of seven-star floating insects has decreased, and Chrysopa is rarely found. The decrease of natural enemies and the inability to control the spread of aphids are the main factors leading to the occurrence of aphids.

Fourth, the awareness of prevention and control is weak. In recent years, due to the adjustment of farm agricultural planting structure, according to the staff of China Agricultural Network, planting a large number of corn, fruits, flowers and garden plants is easy to cause aphid harm. However, because there was no outbreak of aphids in normal years, especially in previous years, farmers' awareness of prevention faded, and most of them did not carry out pre-control work, resulting in a high population base of aphids.

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