Effective fertilization measures for corn

Corn is a “voracious” plant, so the amount of fertilizer is often one and a half to two times higher than that of rice. Therefore, to save fertilizer while still achieving high productivity and economic efficiency, Binh Dien Fertilizer Joint Stock Company has produced many types of fertilizer with high nutritional content, suitable for corn.

Although corn belongs to the grass family, related to rice, its stem is not hollow like rice. Perhaps that is why corn needs a lot of water, but cannot grow in water-filled fields. When it is young, just too much moisture in the soil can harm the growth of corn, and even kill the plant. In corn, the part harvested for food is the corn cob that is located halfway up the stem, not at the top like rice.

An important and different characteristic from rice is that corn is a C4 plant that photosynthesizes. Plants in this group have the first photosynthetic product with 4 carbon radicals, not 3 carbons like rice. This characteristic is extremely important, making corn capable of producing higher biological and economic productivity than rice, in the same growing period.

Corn yield is higher than rice because the photosynthetic intensity of corn is greater than that of rice. On the other hand, to have such high biological and economic productivity, corn needs to be provided with a higher amount of nutrients than rice. For example, a corn field gives us 10 tons of grain, the plant takes away about 269 kg N, 111 kg P205 and 269 kg K20, along with 56 kg Mg, 34 kg S, 19 kg Cl. Meanwhile, to achieve 10 tons of rice with 14% moisture, the rice plant takes away about 160 - 180 kg N + 30 - 40 kg P205 and 18 - 210 kg K20/ha.

But when recommending the amount of fertilizer for corn, it is not about what substance, the more the plant takes, we have to apply more, but also based on the ability of the soil to supply the plant to fertilize. For example, with medium and late maturing corn varieties, on alluvial soil, in addition to 8 - 10 tons of decomposed manure, it is necessary to apply 150 - 180 kgN (326 - 391 kg of urea), 70 - 90 kg P205 (430 - 560 kg of superphosphate or fused phosphate) and 80 - 100 kg K20 (133 - 167 kg of potassium fertilizer/ha). On poor soil, the recommended amount of potassium to apply increases by about 50%.

The principle of fertilizing corn is based on the amount of nutrients the plant takes up, we need to compensate with an equivalent amount of nutrients to maintain soil fertility, so that the next crop's yield does not decrease compared to the previous crop.

In the above recommendations, in addition to the remaining corn stubble in the field, which will continue to return organic matter and some minerals, adding 8-10 tons of manure will also contribute a large amount of organic matter and minerals.

Therefore, the recommended amount of pure fertilizer including N, P and K to be added will be based on the amount of product we plan to achieve in order to achieve a yield of 6 - 7 tons of corn grain on a large area. The above is the recommended amount of fertilizer from single fertilizers (urea, superphosphate and potassium).

In reality, many farmers fertilize whatever they have, often combining single fertilizers with NPK fertilizers without fully understanding the nutritional content of each type of fertilizer, so the quantity and ratio between nutrients are very different, leading to waste of fertilizers and low productivity, sometimes achieving high productivity but the cost of fertilizer is quite high, reducing economic efficiency and further polluting the environment.

To serve corn production in the Northern Delta, Binh Dien has produced two varieties of corn 1 and corn 2, which are used very well by farmers. For example, in Tho Xuan, Thanh Hoa, in 2006, farmers used a fertilizer base of 400 kg of manure + 20 kg of phosphate fertilizer + 16 kg of urea and 7 kg of potassium fertilizer/500 m2. This is equivalent to 204 kg of N + 92 kg of P205 and 117 kg of K20/ha; the total NPK is 413 kg.

As for the Dau Trau fertilizer base, it uses 2 types of corn 1 and corn 2, also applying 400 kg of manure, 22 kg of corn 1 fertilizer and 10 kg of corn 2 fertilizer/500 m2. This is equivalent to 146 kg of N + 85 kg of P205 and 87 kg of K20/ha. The total NPK is 318 kg/ha, resulting in a yield of 5.67 tons of corn kernels/ha, higher than the control of 640 kg of corn kernels/ha and a profit of 2,279,600 VND/ha higher than the control.

Currently, Binh Dien also has many other types of fertilizers such as NPK growth 19-12-6+TE, which is very suitable for the initial growth stages of corn, used as basal fertilizer and fertilization when the plant is young. When applying basal fertilizer, only use about 150 kg/ha (15 kg/1,000 m2), apply fertilizer in rows, then cover with a thin layer of soil and sow the seeds so that the corn seeds do not come into contact with the fertilizer when sprouting.

In the Northern provinces, Dau Trau fertilizer is used as a base fertilizer before sowing. The second top dressing also uses Dau Trau growth fertilizer, which should be applied early when the corn has 4-6 leaves, with a fertilizer dose of about 250 - 300 kg/ha (20 - 30 kg/1,000 m2). Apply fertilizer to the furrow and then mound soil around the base, avoiding applying too close to the base as this will damage the plant.

The type of NPK with firm grain 16-6-19+TE is suitable for the final top dressing, that is, when the corn is ready to twist the ears and differentiate the flags, the amount of fertilizer is about 250 - 300 kg/ha (25 - 30 kg/1,000 m2). The method of fertilizing is the same as the second top dressing.

Regarding dosage and number of applications, it is specifically stated on the packaging. Please read carefully before using. The above recommended level is for general use for medium to late-maturing varieties and for large areas of land. For specific plots, please combine experience from the previous crop and previous year to increase or decrease accordingly.

According to Bannhanong