Autumn peanut cultivation experience sharing: master these planting key points
The peanut yield per unit in China's production areas is relatively low, the economic benefit for farmers is not high, and this suppresses the development of the peanut industry. In the southern provinces of China, farmers can increase their income by planting two crops a year in spring and autumn. Based on many years of practical experience, the author summarizes the high-yield cultivation techniques for autumn-planted peanuts as follows:
1. Deep plowing and land preparation, apply sufficient base fertilizer
Peanut is a deep-rooted crop, and its root mass is distributed in the living soil layer. The most suitable soil conditions for its growth and development are a deep living soil layer, a loose plow layer, sandy loam that does not scatter or harden when dry and does not stick when wet, which is favorable for deep rooting.
1) Deep plowing: use an ox plow or tractor to plow 20-25 cm deep, and land preparation can be carried out 10-15 days in advance. Achieve two plowings and three harrowings, plowing the soil deep, harrowing it fine, and leveling it, and after sun exposure and weathering, form a loose and moist soil layer.
2) Ridging: in areas where the soil is strongly sandy, sea winds are strong, and the soil is prone to drought. Autumn-planted peanuts should be grown on beds to increase the area exposed to sunlight, raise soil temperature, and increase the soil layer. The bed height is 10-15 cm, and the ridge furrow is 30 cm deep and 30 cm wide.
3) Apply sufficient base fertilizer: peanut roots have strong absorption capacity, and peanut seeds contain large amounts of fat and protein. The main fertilizers needed are nitrogen, phosphorus, potassium, and calcium, with phosphorus and potassium requirements higher than those of other crops. According to research results from the provincial Academy of Agricultural Sciences, when the yield per mu is 266.5-290 kg of peanuts, it is necessary to absorb 16.01-19.46 kg of nitrogen, 3.38-3.88 kg of phosphorus, and 7.8-10.24 kg of potassium; the ratio is 1:0.22-0.9:0.49-0.53. However, because peanuts can fix nitrogen through root nodules, the fertilization ratio can generally be carried out at 1:1:2.
Peanut base fertilizer is mainly decomposed organic farmyard manure, combined with phosphate fertilizer, plant ash (or potassium chloride), lime, etc. Autumn peanuts generally flower about 20 days after full emergence, and the vegetative growth period is shorter than that of spring peanuts (generally 110-120 days). In the early stage, they are also in a high-temperature and rainy season, so fertilizers decompose quickly and are easily consumed. Therefore, sufficient base fertilizer must be applied. Otherwise, due to insufficient early nutrition, the plant's vegetative growth is poor, resulting in delayed branching, few branches, and low yield.
For base fertilizer, apply 3000 kg of high-quality farmyard manure, 20 kg of superphosphate, 15 kg of peanut bran, and 100 kg of plant ash per mu, add 30 kg of lime, mix them, and compost until decomposed for use as base fertilizer.
2. Carefully select seeds, sow early at the right time
1) Seed selection: the nutrients needed for peanut seed germination and emergence are supplied by the seed itself. As the saying goes: large seeds make strong seedlings. Selecting plump, large seeds is an important measure for strong and uniform seedlings. Before shelling, sun-dry the pods for 2 days to break seed dormancy and increase the germination rate.
2) Pre-sprouting: soaking seeds to promote germination in autumn-planted peanuts can effectively increase the germination rate and achieve the effect of full and uniform seedlings in cultivation. Soak the seeds in 40°C warm water for 4 hours, remove them, spread them on a straw mat, and keep them moist. After 12-24 hours, when the white tip (radicle) appears, select the sprouted seeds for sowing. If it rains and sowing cannot be done, place the pre-sprouted seeds in a cool, ventilated place and spread them in a thin layer, but be careful to inhibit sprout growth.
3) Sowing early: in tropical and subtropical regions, autumn-planted peanuts are best sown during the period from “Start of Autumn” to “End of Heat”. Sowing too early easily causes excessive vegetative growth, more pests and diseases, and is not conducive to flowering and pod setting; the temperature during the maturity period of autumn-planted peanuts must be above 18°C. If sowing is too late, the later stage will have low temperature and drought, pod development will be poor, there will be many empty and shriveled pods, and the yield will be low.
3. Reasonable close planting, ensure full stands
The sowing period for autumn peanuts is in an environment of high temperature and abundant rain, so sowing density should be appropriately increased at planting time. Sow 22,000-24,000 seeds per mu, with two seeds per hole, in shallow furrow drilling. If the fertilizer is of high quality and high concentration (such as pig manure), it is easy to injure the seeds, so the method of soil separation should be used, that is, spread a thin layer of river sand in the shallow furrow, sow the seeds, then cover the seeds with a layer of river sand, and then cover with a thin layer of soil.
After emergence, check the seedlings and fill gaps in time to ensure a full stand. For two seeds sown per hole, if one seedling is missing, it does not need to be filled in; if the whole hole is missing seedlings, transplant seedlings in time to fill the gap or directly sow pre-sprouted seeds to fill the gap.
4. Strengthen management, topdress in time
1) Drain during waterlogging and irrigate during drought: peanut is a crop that needs more water, and its water requirement pattern is “little at both ends and more in the middle.” Autumn peanuts have more rain in the early stage, and the seedling stage is afraid of waterlogging, so ditches should be cleared and drainage should be timely. Generally, furrow irrigation and sprinkler irrigation are better, and small amounts of water should be applied carefully, but flooding irrigation must be avoided. Prevent plants from drought and wilting; without irrigation conditions, it is difficult to achieve high yield.
2) Intertillage, weeding, and earthing up: carry out the 1st intertillage and weeding when the plant has 3-4 true leaves, carry out the 2nd after 10 days, and carry out the last intertillage at full flowering stage. According to farmers' experience: the first hoeing should be shallow, the second should be deep to loosen the soil, and the third hoeing should be meticulous. The 1st earthing up is carried out together with the last intertillage, using a small hoe to move loose soil from between the rows to the base of the peanut, and after 10 days, carry out the 2nd earthing up together with cleaning the bed furrows.
3) Topdress in time: after full emergence, apply 5 kg of urea per mu by broadcasting when the soil is moist after rain to promote early branching and early flowering and pegging. Peanuts absorb 60% of their total lifetime fertilizer uptake during the flowering and pegging stage. Therefore, fertilization during the flowering and pegging stage has high utilization efficiency and a significant yield-increasing effect. At this time, apply 20 kg of compound fertilizer per mu. After flowering ends, broadcast 60 kg of black-and-white ash per mu (30 kg of lime powder and 30 kg of plant ash each) to prevent premature senescence and premature seedling decline in the later stage.
4) Spray trace elements: use 100 g of sodium borate per mu mixed with 50 L of water, and spray once each at the beginning of flowering and at full flowering. Boron fertilizer can stimulate pollen germination and pollen tube elongation, which is beneficial to fertilization.
5) Pest and disease control: for insect pest control, use 600-fold malathion solution for spraying at the seedling stage, and use 800-fold trichlorfon solution for spraying in the middle and late stages. For leaf spot disease and rust disease, start applying chemicals at the flowering stage. Use 1:2:200 Bordeaux mixture or 150-fold colloidal sulfur solution and 800-fold chlorothalonil alternately, and the control effect is good.