"four sprays and one row" to promote high yield during full fruit ripening period of planting peanuts

The full ripening period of peanut means that half of the plants have full pods to most of the pods are full, that is, the period of maturity and harvest. The middle-maturing varieties lasted about 35-45 days, the very early and early-maturing varieties were shorter, the late-maturing varieties were longer, and the summer direct seeding peanut was equal to or slightly longer than the spring sowing variety. The full fruit ripening period of spring peanut in Shandong and Hebei is from the first ten days of August to the middle of September, and the summer direct seeding peanut is from the end of August to the first ten days of October. The increased fruit weight during this period can generally account for more than 60% of the total weight, so strengthening management in this period is expected to greatly increase the output.

The main tasks of field management during this period are to slow down the speed of leaf senescence and yellowing, postpone the time of defoliation, maintain a larger green leaf area, maintain a longer functional time, enhance photosynthetic intensity, improve photosynthetic efficiency, and increase nutrient accumulation; promote the transport of nutrients in stems and leaves into pods, increase transport rate, speed up pod enrichment, and form economic yield as soon as possible; control the damage of major diseases and pests and reduce the amount of yield loss. The main measures of field management are "four sprays and one row":

The main results are as follows: 1. after foliar fertilizer spraying peanut enters the full fruit ripening stage, due to the aging of root system, the decrease of absorptive capacity and nodule nitrogen fixation and nitrogen supply capacity, early defoliation is often caused by de-fertilization. The foliar absorption capacity of peanut is enhanced in the later stage, and foliar fertilizer spraying for many times in time can effectively supplement nutrients and delay defoliation, which has many advantages, such as rapid action, high absorption and utilization rate, low investment, great benefit and so on. The types of fertilizer sprayed are easy to choose foliar fertilizer with more phosphorus and calcium, such as "Jiataifeng" made in Taiwan.

Second, if the field where the regulator has not been sprayed before or has not been sprayed with regulator, it is necessary to spray 800-1200 times liquid "Zhuangyuan" (be careful not to spray it on the ground), which can obviously thicken the leaves, thicken the leaf color, delay the time of falling leaves, speed up the expansion and fullness of pods, enhance drought resistance and waterlogging tolerance, and slow down the premature senescence caused by spraying paclobutrazol and regulators containing this component.

Third, fungicide leaf spot, especially net spot and brown spot, is one of the main causes of early defoliation of peanut. Once it occurs and spreads rapidly, a large number of leaves fall off in a few days, resulting in a reduction in yield. Combined with foliar spraying fertilizer and adding broad-spectrum fungicides such as mancozeb or methyl topiramate, the damage can be greatly reduced and leaf defoliation can be delayed. The effect of carbendazim and fungicides mainly composed of carbendazim is not good, and it is easy to induce rust in the later stage.

4. The main pests that damage peanut leaves in the later stage of insecticide spraying are leaf-eating pests such as Helicoverpa armigera, bridge insects and leaf mites (red spider). The former is easy to occur under the condition of high temperature, rain and humidity, while the latter occurs under dry climate, so attention should be paid to inspection. spraying insecticides and acaricides during infancy and spot occurrence. On the basis of previous control of grubs, golden needles, ants and other underground pests, if there are still larvae or victims in the soil layer, sprinkle the quick-killing soil insect fertilizer powder or fill the pier with methyl isothiophos. Recently, the defecation amount of grub adults and the damage of middle and upper leaves in peanut field were examined, and the damage of larvae was expected to be serious, so the control should be strengthened.

Fifth, there are more Rain Water in the late growth period of drainage and waterlogging prevention peanuts, and too much stagnant water in the ground and too much diving in the soil plough layer is also one of the reasons for early defoliation, and serious ones may also cause rotten fruit, so it is necessary to eliminate stagnant water in the field and diving in the plough layer in time.

In addition, when most of the leaves fall off, the top leaves and stem branches turn yellow, and most of the pods are full. If the harvest is late, more fruit will be lost, the yield will be reduced, and the quality will become worse.