Management of Peanut Field in High temperature and Rain Weather

Entering the rainy season, especially after July, the hot, overcast and rainy weather increases. Spring sowing peanut is in the stage of both vegetative growth and reproductive growth, the lower needle and vegetative body of the plant grow rapidly, the land with good water and fertilizer conditions is easy to overgrow, and the aboveground stems and leaves grow too vigorously, which affects the transfer of nutrients to reproductive growth, resulting in few pods but not concentrated. Peanut seeds are small, not full, and there are many empty pods, thus affecting yield and quality. High temperature, overcast and rainy weather is very easy to cause the occurrence of peanut diseases and insect pests. After continuous rainfall, we should do a good job in peanut field management, timely prevention and drainage of waterlogging, control of overgrowth of peanuts, prevention and control of diseases and insect pests, and lay a good foundation for a good harvest of peanuts.

1. Do chemical control in time to control the growth of peanuts. Good soil fertility, more Rain Water and high temperature can easily cause overgrowth of aboveground stems and leaves in the middle and later stage, consume too much photosynthate, inhibit pod development and affect the increase of yield. Therefore, according to the peanut field growth and climate characteristics, timely and reasonable chemical control to prevent peanut overgrowth and lodging, the effect on peanut yield is very obvious. When the peanut plant height reached 35-40 cm, it was used for the first time when the ridge was closed in the field, about mid-July; according to the growth situation, when the plant height was 45-50 cm, it was applied for the second time in early August. The commonly used control agents Zhuangyuan and 15% paclobutrazol wettable powder and so on. When applying chemical control agents, we should pay attention to the following points: first, to avoid excessive dosage at one time, we can use multiple small amounts of method, divided into 2 to 3 times, in which the total amount of paclobutrazol should not exceed 40g/ mu, so as not to affect peanut pod development due to excessive dosage, and aggravate the occurrence of leaf diseases, leading to early leaf death and shedding, resulting in premature senescence of plants. Zhuangyuan can increase the chlorophyll content of peanut leaves, increase the photosynthetic rate, improve the distribution of photosynthates in peanut, promote pod development, increase root activity, delay root senescence, inhibit aboveground vegetative growth, dwarf plant height, prevent overgrowth and lodging, and steadily increase production by more than 10%. About 20g / mu, 30~40kg mixed with water, foliar spraying, the plant is obviously overgrown, the dosage can be slightly increased or applied twice, but the total amount should not exceed 30g / mu. The amount of peanut field with poor growth can be reduced appropriately.

2. Timely drainage to prevent rotten fruit. Continuous days of rainfall has caused peanut soil moisture saturation, some plots have reached oversaturation, the vegetative growth from pod setting to mature stage is gradually slow or even stopped, and the water demand is reduced. Too much water in the soil is not conducive to pod development, and even cause rotten fruit. When the soil moisture exceeds 80% of the maximum field capacity, waterlogging must be carried out. The waterlogging-prone land should dredge the drainage ditch in time, and the mountain and hilly land should dig the ditch under the Weir to make it communicate with the waist trench and peanut ridge. Not only discharge open water, but also discharge diving, not only solve the "half waterlogging", but also prevent soil erosion, and Weir collapse, so that light rain does not waterlogging, heavy rain does not cause disaster.

3. Do a good job in the control of diseases and insect pests. Peanut diseases mainly include peanut leaf spot (brown spot and black spot), net spot, powdery mildew, scab and so on. Fungicides were used to control peanut diseases in the first and middle of July. Spray Pink, mancozeb, carbendazim, chlorothalonil, etc., every 7-10 days, 2-3 times in a row. The disease prevention effect is better when the above agents are mixed. The main targets of pest control are cotton bollworm, aphids and grubs. Where possible, insecticidal lamps should be used to control underground pests in peanut fields such as grubs; 48% chlorpyrifos 250 ml ~ 300 ml per mu or 50% phoxim EC 300 ml ~ 400 ml can be used for chemical control. Diluted with appropriate amount of water, the root is irrigated with a sprayer after the nozzle is removed. 1500-fold solution of cypermethrin can be used to control Helicoverpa armigera, bridge worms and aphids at the initial stage.

4. prevent premature senility and spray foliar fertilizer in time. In peanut production, due to one-time fertilization, too much plastic film mulching, excessive chemical control and poor nutritional growth in dry and thin land, it is easy to lead to the occurrence of premature senility in the late growth stage of peanut, such as serious diseases and insect pests. Premature senility is more serious, and premature senility has become the main obstacle to the further improvement of peanut yield. In the late growth stage of peanut, foliar spraying 1 / 2% urea or 0.2% potassium dihydrogen phosphate solution, or foliar fertilizer rich in NPK and multi-micronutrients for 3 times, with an interval of about 1 week. In foliar topdressing, attention should be paid to the timing and quality of spraying. First of all, there is dew in the morning, high temperature at noon and rainy days, do not spray; secondly, under the premise of fully stirring evenly, spray should be uniform and thorough.