Much of the corn crop has been planted in the Corn Belt but establishing a good plant stand is most important for getting good yields. The seedling stage is the most critical phase in the life of a corn plant. The young stage of every organism is critical for development and productivity of the adults. If we understand how our crops grow, we can do a better job of meeting the needs of our crops and improve yields. Let’s look at what happens as the young corn plants develop.
• V1 to V2: It takes 110-120 Growing Degrees for corn seedling emergence. The seedlings emerge when coleoptile, the spear-like leaf pierces thru the ground. First and second leaves develop six to seven days after the seedlings emerge.
• The first roots start to supply water and nutrients to the young seedlings. Roots are very small and banded fertilizer close to the roots at this stage should be very helpful in stimulating early growth.
• V3 to V4: About two weeks after emergence, third leaf starts to develop. Seedling roots stop at this stage and the secondary roots known as “Nodal Roots” start growing. These become the permanent root system of the plant.
• The growing point stays below ground for three to four weeks and is protected from frost or insects on the surface. Don’t cultivate too close to the plant after this stage because the roots may be damaged.
• Freeze at this stage may hurt the leaves but growing point is not destroyed since it is below ground. The nodal roots are growing fast and start taking over the responsibility of gathering water and nutrients for the whole plant. Root hairs also start growing.
• V5: Four nodes develop below the ground. Generally, the first node above the ground is the 5th node. Even at this early stage, leaf and ear shoots are starting to develop. Take care of the young plants and you will have productive healthy adults and a good crop.