New strategies for high yield of selenium-rich black corn

Due to the pursuit of healthy food and functional food in the market, black corn has become popular in the market. In recent years, the planting area has gradually expanded, and the development situation is promising. Several new techniques for high yield cultivation are recommended.

First, the former heavy cultivation techniques of black corn.

Practice has proved that the critical line for fertilizer and high yield of black corn is "not at ear stage, but at seedling stage", so the focus of work should be moved forward to seedling stage.

1. The soil is deeply loose. Change ploughing once a year to one deep loosening every three years, popularize and apply omni-directional rodent type deep loosening device, the deep loosening can reach 50 cm, and increase the soil water storage capacity by more than twice.

2. Pay close attention to the planting foundation

(1) seed foreskin. The seed coating agent of both plant protection and nutrition should be selected.

(2) vigorously popularize and apply all kinds of precision and semi-precision sowing machines. When sowing, the seed fertilizer should be sown layer by layer, and the fertilizer should be more than 5 cm below the seed.

3. Improve the overall level of fertilization. At present, the key fertilization techniques of black corn are as follows: balance, front weight and side depth.

The main results are as follows: (1) constantly adjust the proportion structure of fertilization elements and modify the critical value of soil element content. At present, the suitable range of nitrogen, phosphorus and potassium in our province is 1 ∶ 0.7 ∶ 0.6-07.

(2) pre-heavy fertilization is the core part of former heavy-duty cultivation techniques, and base fertilizer and seedling fertilizer should be re-applied. For spring sowing black corn and summer sowing corn with longer growth period, 70% of the required phosphorus and potassium fertilizer and 70% of the nitrogen fertilizer were applied in the early stage, and the remaining 30% of the nitrogen fertilizer was applied at the panicle stage. For summer sowing black corn with short growth period, one-time bottom application of all fertilizers or one-time early application at seedling stage is recommended.

(3) Deep fertilization on the root-seeking side. Its purpose is to apply fertilizer to the area where the root system is concentrated and to increase the fertilizer concentration in the local soil. Therefore, topdressing should adopt the methods of reverse application, surface application and near application, and advocate deep topdressing on the root-seeking side, that is, topdressing at 15 cm on one side of the black corn plant.

4. Seedling stage management

At the seedling stage, the black corn was ploughed at a depth of more than 20 cm, and the black corn was ploughed only once during the whole growth period.

(2) determine the seedlings in time and keep the seedlings evenly. It is appropriate to fix the seedlings of black corn with five leaves. In the case of high density planting, the seedlings should be evenly distributed to ensure that the plant spacing is uniform, the seedling age is uniform, and the population is neat.

(3) popularize the special herbicide "du'a", which is used both before and after seedling.

5. Improve the overall level of black corn. Density should include three aspects: quantity, quality and population distribution. Only when these three aspects are reasonable, can the overall level of density be improved.

Second, the inhibition technology of premature senescence in the later stage of black corn.

The phenomenon of premature senescence in the later stage of black corn is a prominent production problem affecting its potential to increase production. According to our researchers, folic acid treatment of maize seeds can enhance the resistance to premature senescence in the later stage. The field experiments of Shendan 7 and Yedan 13 showed that this technical measure could increase the yield of maize by more than 10%.